plastic processing aid described in detail

Propylene can become non-polar and polar materials to enhance adhesion and material compatibility bridge. Add a maleic anhydride
grafted polypropylene in the production of filled polypropylene, can greatly improve the affinity and polypropylene filler and
filler dispersion. It can effectively enhance the PVC flame retardant  dispersion of the filler in polypropylene to improve the tensile and impact
strength of filled polypropylene. Typical applications include maleic anhydride-grafted polypropylene: plastic processing aid
compatible inorganic reinforcing material (glass fiber) and filler material (calcium carbonate, talc, etc.) and polypropylene
coupling between the polypropylene / nylon alloys improving agent of polypropylene with a polar material (metal, nylon, etc.)
adhesion. HR tear the rubber resin added can  Polyethylene wax significantly increase the hardness of the rubber, aging resistance, abrasion
resistance, tear strength, tensile strength, and kneaded with an easy processing, easy and good coloring thermoplastic,
electrically insulating properties. It includes: 1, compared with one-component sealant, plastic processing aid faster overall
curing, the electronic module can be encapsulated and the stearic acid larger objects (depth greater than 7mm) 2, compared with the bicomponent
lower cost. 3, compared with epoxy resin, with excellent resistance to high temperature, anti-aging and anti-ultraviolet function.
Potting electronic modules, LED display, the pixels, backlight, and other electronic components: Typical uses.

Polyvinyl WSD processing aid is one of five common plastic

Polyvinyl chloride (PVC) is one of five general-purpose plastics , its products have a wide range of uses. However , PVC thermal stability exists disadvantages must be added when a suitable heat processing stabilizer to inhibit thermal degradation. Heat stabilizers Metallic stearate commonly used in industry are mainly inorganic lead salts and organic tin, metallic soaps . However , one of the most common varieties are poisonous , which not only limits the scope of application of PVC products and harm to the environment and their use of labor health PVC products are produced with sustainable growth and rapid deepening. To protect the environment , improve the working conditions of health in recent years in Europe , America, Japan, and the country has been developed and implemented to limit the use of hazardous chemicals policies and regulations. Therefore , research and development at home and abroad are set off and promote the use of non-toxic substance heat stabilizers to replace traditional toxic varieties boom. Rare is the advantage of PVC plasticizer our resources , rare earth compounds as PVC heat stabilizer application has attracted wide attention . In principle , since the rare earth hydroxide with a weakly alkaline medium and can absorb HCl, and hence, a heat stabilizing effect PVC . But until now , although the literature involving alkaline earth metal hydroxide is calcium hydroxide as a particular application of PVC heat stabilizers , but no rare earth hydroxide is used as PVC heat stabilizers research reports . Recently , the experts for the development of cost-effective environmentally friendly zinc-based PVC heat stabilizers, inorganic compounds as application performance heat stabilizer for a more systematic study found that lanthanum hydroxide is an effective synergist heat stabilizers.

WSD plastic processing aid industry is currently technical level

According PvC plastics processing industry is currently technical level , although a variety of products , recipes using different households but still mixed metal stabilizer system based. In the past, products processing factories with one-component , single-species steady purchase Beng various additives, formulated his own mixed use , PVC stabilizer processing a variety of PVC products, now has developed into the stabilizer born less "factory according to user requirements , composite production, and can be . ne-paeks ( one package ) sold stabilizer products, deepen and broaden the technical support services , so varieties of PVC compound stabilizer designed for user needs , and many more special type of master such as liquid composite stabilizer , mainly for soft products ( films, leather , etc. ) : clean composite solid lead salt stabilizer , mainly used for rigid materials such as articles and cable : for a single machine and specialized product requirements design composite stabilizer ( such as ZFZ products dedicated to the sole material ) .Compatibility with the ratio of the composite stabilizer , based on long production experience , is still a variety of metal salts as Lord stabilizer, with its complex and adduct of synergy effect . Should , while accompanied by a variety of auxiliary stable agents, to further enhance the stabilizing effect of the metal PVC heat stabilizer salt system. In the design of the liquid component of a composite stabilizer , metal salts of the general control of the content of 2% -15 % ( of metal ion , the weight percentages ) phosphite, vinegar, 10% -50 % , 2% -10 % of antioxidant , light stabilizer 1% to 4% lubricant 1% -10 % 20% -40 % solvent . The solid composite stabilizer , generally available Pvc resin together with modified and processed cPE, EvA etc. ) as a carrier excipient , the control content of 10% -50 % metal salt ( metal ion count , percent by weight) , a lubricant 5% -15 % auxiliary stabilizer 5% -10 % .

the mutual solubility of the mixed resin and plastic processing aid in

 Auxiliary plasticizer; inserted only partially crystalline molecular plasticizer amorphous regions of the polymer, the plasticizer, the plasticizer is also called non-solvent. Compatibility: the ability to dissolve the plasticizer and resin mixed with each other, and is one of the most basic requirements of plasticizer. Cohesive energy density (CED): energy per unit volume of solvent evaporation. Solubility parameters: the square root of the value of the energy of vaporization per unit volume of solvent. Cloud point (Tc): dilute homogeneous polymer solution and a plasticizer, at a temperature becomes cloudy during cooling. By measuring the cloud point can be estimated plasticizer and resin compatibility. The lower the cloud point, a plasticizer compatible with the polymer, the better. Plasticizing efficiency; plasticizing efficiency of the resin reaches a certain degree of softness is called the amount of plasticizer plasticizer. Plasticizing efficiency is a relative value, the plasticizer can be used to compare the plasticizing effect. The method used for representing plasticizing efficiency glass transition temperature (Tg) and reduce the decrease in modulus is represented. Oxidation of the polymer is the time increases with the decrease of the performance of the polymer, also known as auto-oxidation. Into the induction period, a strong oxidizing period. Antioxidants; refers to polymers by oxidation and slow the aging phenomenon can play the role of a class of chemicals. Primary antioxidant; antioxidant is considered to be the main cleaning agent, a free radical, it is through the coupling reaction (i.e., the termination reaction) to give a hydrogen atom or to prevent the damaging effects of free radicals in the polymer. Secondary antioxidants; role of antioxidants is to help decompose the peroxide oxidation of the resulting polymer. Antioxidants including an aid phosphite 2, 3 thioether antioxidants, metal deactivators metal ion deactivators; preventing the heavy metal ion induced oxidation of the resulting polymer material, often referred to as metal ions blunt agent or a metal deactivator, a metal chelating agent, also known as copper inhibitors. Stabilizer: to prevent or retard the polymer during processing, storage and use of chemical aging deterioration. Thermal stabilizers; mainly for PVC and other chlorine-containing polymers, which will not affect the processing and application, but also a certain degree of thermal decomposition of delaying the action of a class of additives. Light stabilizers; Where can inhibit or slow down the aging of optical oxygen substance called ultraviolet light stabilizer or stabilizers. Radical scavengers: a class of piperidine derivatives light stabilizer with steric effects, referred to as hindered amine WSD zinc stearate  light stabilizer (HALS) - aging or photoaging: molecular material long-term or short-term exposure to the sun set under strong fluorescence, due to absorption of UV energy, causing auto-oxidation reaction, leading to degradation of the polymer, making the products discoloration, brittleness, performance degradation, which can not be reused. This process is called oxidative aging or photoaging light flame retardants; able to increase the flame resistance of the material substance called flame retardants. They are mostly first periodic table V, compound VII and combustion speed of the group III element: refers to the length of the sample per unit time of combustion. Synergistic effect: refers to two or more with the use of additives, the total effect is greater than the sum of the individual effects when used alone. Synergy system: complex flame retardant with the use of the interaction between the flame-retardant to improve performance, the system is called a synergistic effect. Synergistic systems commonly antimony - halogen system, phosphorus halide system, phosphorus - nitrogen system. Burning speed: denotes the length of the sample per unit time of WSD Aluminum hydroxide  combustion. Burning speed is horizontal and vertical burning combustion method to measure too. Oxygen index: refers to the sample continued to burn like a candle shape, nitrogen - oxygen mixed gas stream must minimum oxygen content. External friction: polymer materials during the molding process, the polymer melt friction between the surface and processing equipment. Friction: polymer material during the molding process, the molten polymer molecules exist between friction. Lubricants; polymer to reduce friction and external friction, improved melt flow plastics, polymer material during processing to prevent the sticking of the device to ensure the surface smoothness of the added substance called lubricant. Lubricants: prior to processing the plastic ingredients, add a certain compatibility with the polymer lubricant and uniformly dispersed into the material, can reduce the friction between the resin molecules sky lubrication. External lubrication in two ways: one is in the polymer material forming the lubricant coated on the surface processing apparatus, allowed to melt at processing temperatures, and the metal surface of a "thin layer" is formed, the plastic melt and processing equipment to isolate, without adhering to the equipment, or ease of stripping off the roll; Another is compatible with the polymer is very small, it is easy to migrate from inside the polymer during processing On the surface, thereby forming WSD Calcium stearate  a spacer layer material, before the processing of the ingredients added to the plastic dispersion, and migration to the surface during processing, providing lubrication. Mold release agent: Mold and machining the workpiece remain completely chemically inert substance called a release agent. Blowing agents; make a class of blowing agents are liquid or plastic state within a certain viscosity range of rubber, plastic material forming the microporous structure.

PVC processing aid and the use of its characteristics

ACR acrylic esters (Acrylics) Abbreviation is generic acrylic ester series modifier , based acrylic ester polymer of copolymer . ACR is a copolymer of methyl methacrylate and acrylic acid ester as  WSD Calcium stearate a white flowable powder. Depending on acrylic esters , ACR different properties and uses the proceeds of its wide range of applications. ACR as processing aids , plasticizers can significantly shorten the time to accelerate melting and promote plasticized , extruded products can make to improve the balance of torque , making it even plastics ; pair of rolled products , adding ACR to overcome the surface wrinkles , help roll  WSD Plastic impact modifier package of materials , reducing air bubbles ; for vacuum forming products , adding ACR to improve melt extensibility overcome melt fracture phenomenon , easily deep drawing , and make uniform product thickness . From the looks of the article , ACR can significantly improve the surface gloss of products, to make products look smooth and delicate. The processing aids wide range of applications , in addition to rigid PVC products, the semi- rigid and soft PVC products, PVC products all have the effect of improving  WSD stearic acid processing performance for applications that require good weather resistance of opaque PVC products such as pipes, construction material ( siding, doors and windows profiles, pipe fittings , blinds, rain gutters , etc. ) as well as injection molding, blow molding products.

Use the principle of PVC processing aid

In industrial production, in order to improve production processes, improve product quality and yield, or to give the product of a specific application performance by adding auxiliary chemicals. Also known as the additive. However, as an important component of the product matrix, the product shape, structure, performance of large doses have a significant impact of additional material, generally not included in the scope of aid. Additives wide range of applications, usually re-dubbed the role of one pack stabilizer  object names, such as polymeric additives, water treatment, metal surface treatment agent. There are some common additive selection considerations, such as: ① use of the additive requirements. Additives appearance, odor, contamination resistance, durability, electrical properties, weather resistance and so the use of direct impact products. ② processing conditions additives adaptability. ③ durability additive. Loss additive mainly through evaporation, extraction and migration pathway 3, the species must be selected appropriately according to the environment and the article processing conditions. ④ compatibility with polymer additives. Comprises mixing in impact resistance and stability of each may be a problem between them. ⑤ additive toxicity. Food and drug packaging materials, water pipe, medical equipment and other polymer materials, products, their health mainly depends on additives used. ⑥ synergistic and additive effect between proposition. If chosen appropriately, the mutually reinforcing, and can reduce the total amount of additives. The use of additives principles:
The current provisions of the international system can be divided into two, one is to allow the use of additives "exhaustive" "whitelist" lists, and the other is listed aids disabled "disabled list." After years of practice, "disabled list" to be found there is a big drawback: the lack of new substances binding. Plastic profiles Promoters
Additives a plastic profiles: impact modifiers, such as the production of plastic profiles without impact modifier, plastic profiles will be very brittle, a little collision, easily broken. Commonly  chromium oxide Titanium dioxide rutile used in the production of plastic profiles impact modifier modifier consists of the following three categories: chlorinated polyethylene, polyacrylate, ethylene - vinyl acetate copolymer. Plastics Additives two sections: heat stabilizers plastic profiles are heat-sensitive plastic, so plastic profile production machining, heat stabilizers is essential. Metal heat stabilizers in PVC can absorb decomposition of HCL, it can slow down the rate of decomposition of plastics and extended decomposition time, the production of plastic profiles for the most commonly used compound lead salt, high-efficiency thermal stability, low prices. Plastics Additives three  sections: the main processing aid processing aids plastic molding  PVC lubricants process in order to improve the performance improvements and the development of a class of additives. Plastic profile processing temperature and decomposition temperature relatively close, poor mobility, easy to stick on the device coking, and therefore the production of plastic profiles need a certain amount of processing aid to overcome the defects of plastic profiles itself.

PE modified polyethylene wax and paraffin

A small amount of low density polyethylene (LDPE) was added to the molten wax to form a homogeneous mixture of the polyethylene dissolved, and cooled to obtain a modified PE wax, paraffin wax which is very classic processing methods. Adding a small amount of polyethylene wax crystallization changed, so that the melting point paraffin has heat stabilizer for panel  been greatly improved, improved from 50 degrees to 80-90 degrees, LDPE also has very good toughness paraffin, wax coating containing the PE not easy to crack. Because of these advantages, several decades ago, PE is widely used in the modified paraffin wax coated paper, cardboard, waterproof packaging for food, when very expensive PE film can not be applied to these areas.
PE modified so that the physical properties of paraffin wax has greatly improved, but even the plastic coating applications, it is fundamentally different and polyethylene wax, not  stearic acid paraffin polyethylene + = polyethylene wax.
PE modified paraffin wax can change a small molecular weight (300-400) nature, at higher temperatures, large-volatile paraffin. Bake 180 degrees for 20 minutes, PE modified paraffin thermal weight loss of about 10 percent, a variety of polyethylene wax TGA basically about 0.5%. Modified PE wax used in powder coatings, baking smoke very serious.
PVC external lubricant wax can do, but there are many disadvantages: Since paraffin and small molecular weight PVC resin and incompatible, paraffin easily precipitate from PVC products, wax  Chlorinated paraffin tends to reduce the strength of PVC products. PE modified paraffin wax can not change these properties, but it improves the viscosity increase than pure wax such external lubrication has improved stability than pure wax.
For masterbatches, PE modified relatively pure paraffin wax, the viscosity increased, a shearing force increases, the relative genuine purpose polyethylene wax, PE wax or a modification of the pigment is difficult to effect uniform dispersion.

Look plasticizer industry how to deal with future market

The news is no doubt consumers "Gospel ." With the enhancement of environmental awareness around the world and focus on aspects of chemical hazards to human health , have introduced on phthalates , the most commonly used types of phosphate plasticizers restrictions regulations and technical standards . Our country is in Asia plasticizer production, consumer, plasticizer production capacity of about 300 million tons, production of about 1.5 million tons . Because many companies related to international trade regulations insufficient attention on the face of the titanium dioxide anatase  endless variety of new regulations by surprise, in children's toys , food packaging , consumer goods and medical plastic products such as foreign trade industry has been a huge hit. Despite a greater impact , but the introduction of various international industry regulations is to ensure that the risk of harmful plasticizers are reasonable control and gradually replaced. Although the new international regulations to establish a high technical barriers, but once beyond, domestic enterprises from both technical and market while promoting industrial upgrading plasticizer .
President of the China Plastics Processing Industry Association, Liao pointed out that China's plastics industry is still huge room for development, but we must increase investment in technological innovation , attention to the introduction and training of technical personnel , to strengthen cooperation with universities and research institutes , tracking and abroad the latest trends in technology development , there are efforts to develop proprietary products and technologies with independent intellectual property rights , improve the overall level of technology and independent innovation capability . The role of plasticizer to provide mankind with high quality plastic products is indispensable , but it brings security issues , environmental hazards , pose a new challenge to humanity . R & D use of safe, environmentally friendly plasticizer has become an urgent  pvc additive task development of the industry . Accelerate the elimination of toxic plasticizers and promote the development of new non-toxic plasticizer has become an inevitable trend. Therefore , domestic enterprises must constantly monitor plasticizer regulations related fields exporter latest updates , progress and adjustments and changes , early good response. Second, to increase the new " non-toxic type", environmentally friendly plasticizer research and development efforts , the right to judge the market demand, timely adjustment of the production structure . It is reported that China plasticizer industry after decades of development, the industrial base has a considerable scale . Faced with new international regulations change constantly adjust product structure , more carbon black powder  advanced means of detection , evaluation method is more reasonable , a number of manufacturers have begun to catalyze a great effort under the new study , the separation process , vigorously develop and promote non-toxic , environmentally friendly and biodegradable growth plasticizers, the more cost-effective , more reliable security , a new generation of environmentally friendly plasticizer products to market.

some description depolymerization pigment

In the dispersion process, only the surface of the secondary particles is not enough to wet paints, because such a large size, small surface area of ​​the pigment particles forming group can not meet the requirements of paints and maintaining a stable dispersion state of liquid paint .
Must therefore be subjected to  PVC heat stabilizer external mechanical forces (shear forces primarily) deaggregation these large particles, to restore back to the original level at or near the particle size to small particles form a large surface area exposed to the paint and so that all surfaces are exposed by wet paints.
This means the applied mechanical force, the pigment agglomerates and aggregates restored or nearly restored to the original level of particles or depolymerization process called dispersion process called.
Pigment in the paint in the paint manufacturing process depolymerization is the main, the most energy consuming processes. Make pigment depolymerization external mechanical force, usually by grinding and dispersion we normally use equipment, such as a sand mill, ball mill, three-roll machine, high speed disperser and two roll machine generated.
As a dispersion medium in order to create a liquid vehicle for the pigment (filling) material particles penetrate the surface of the conditions necessary to color (fill) material aggregates and agglomerates can be applied to promote its breakdown external mechanical force, the color (fill) depolymerization material particles, it is better to paint the wetting liquid, which requires grinding and dispersion equipment.
Paint the polishing slurry, the pigment particles depolymerization process, not only can be sufficiently liquid so that wet paint color (fill) material particle surface to improve the stability of the millbase, and with a higher level of pigment dispersion, coloring pigments, cover will be a corresponding increase in strength, gloss and other paint film performance is also improved. So the selection of an efficient grinding and  aluminum stearate dispersion device, can greatly improve the dispersion of pigment in the paint level, thereby improving the millbase while reducing the amount of pigment stability, improve the quality of paint and coatings.
3, stabilization:
Depolymerization has been wetted pigment particles distributed to a large number of paints continue to go, so there is enough paint coated on the periphery of pigment particles, and isolated from one another, thereby reducing the attractive force between the pigment particles, to avoid the mutual contact between the pigment particles, such that each has to be gathered and the solution of the pigment particles are moistened sufficiently thick, continuous, non-volatile dispersion of film-forming material is permanently open, the dispersion applied in the absence of under the control of mechanical forces, the pigment particles will not appear again coalesce into large particles in the process, called the stabilization process, to obtain stability of the pigment dispersion, the purpose is production of the final paint.
Thus, the dispersion of pigment in the  paint is wet, and stabilization depolymerization process three major components.
But, in fact, these three processes are not  calcium zinc stabilizer completely separate, but simultaneous and alternating conducted. For dispersing the pigment in the paint dispersion is formed, the relationship between the three: a wet basis, in order to more fully depolymerization wetting, and to achieve steady state of the ultimate goal.
If the pigment is dispersed in the paint well, to reach a relatively stable state, then had been dispersed pigment particles likely will re-close and gathered into large particles, forming what we call a pigment floc flocculation of pigments is distributed among the inverse process.
Floc pigments and aggregates and agglomerates, although the original-sized particles made of large particle coalescence particle group, but the floc and the latter are essentially different, although it still paints the surface of the package cover, paint particles have been filled the gap, the pigment aggregates and agglomerates the surface of the cladding is air and water, the gap is filled by air, but the micro-flocculation state, in the production of coatings as well as its the use of the Department.

Some of the main flame retardant plastic description

Flame retardants
Most plastics are flammable . With the plastic in the construction, furniture, transportation, aviation , aerospace , electrical and other aspects of the widely used to improve the flame retardancy of plastics has carbon black powder  become a very urgent issue. Inhibiting polymer flame retardant is a class of flammability additives, they are mostly of the Periodic Table Ⅴ, Ⅶ Ⅲ elements and compounds ; especially phosphorus , bromine , chlorine , antimony and aluminum compounds. Sub- additive flame retardants and reactive types . Flame retardant halogen-containing primarily phosphate and Acrylic processing aid  phosphate, a halogenated hydrocarbon , antimony oxide , and aluminum hydroxide . Advantage is easy to use and adaptable . However, the addition of capacity of 10 % to 30% , often affect the performance of plastics . Reactive flame retardant containing the elements actually monomer, it has little effect on the plastic properties . Common reactive flame retardants , halogenated anhydrides such as for polyesters , for epoxy resins of tetrabromobisphenol A, and phosphorus for polyurethane polyol. Flame , the current amount of second plasticizer. Consuming most varieties of plastic flame retardant polyvinyl chloride, polystyrene, polyurethane foam , unsaturated polyester , ABS resin and polypropylene.
Most plastic is flammable , its  titanium dioxide anatase products, which brought a lot of application security risks. Precisely, flame retardants, flame retardants known as more appropriate , because " flame " contains two meanings flame retardant and smoke suppression , compared with the broader concept of flame retardants . However , long time, people have become accustomed to the concept of use of flame retardants

Iron oxide red pigment

Red iron oxide, may be relatively well-known professionals. But we usually see red items, many of which are red iron oxide as raw material. Then, together we know about.
Iron oxide red pigment:
1, iron oxide red pigment Iron Oxide Red for potassium stearate  coloring plastics, such as thermosets and thermoplastics, and rubber products, coloring, such as automobile inner tubes, aircraft inner tube, bicycle inner tube and so on. 2, iron oxide red pigment Iron Oxide Red for a variety of paint color and protective substances, including water-based interior and exterior paints, powder coatings, etc.; also apply to oil paint, including epoxy, alkyd, amino and other primer and surface paint; also be used for toy paint, decorative paint, furniture paint, electrophoretic lacquers and enamels.
3, iron oxide red pigment in the various types of precast concrete products and building materials as pigments or  PVC impact modifier coloring agents, directly into the application of cement. A variety of indoor and outdoor color concrete surfaces, such as walls, floors, ceilings, pillars, porches, roads, parking lots, stairs, stations, etc.; various architectural ceramics and glass ceramics, such as tiles, floor tiles, roof tiles, panels , terrazzo, mosaic tiles, artificial marble.
4, red iron oxide commonly used in construction, rubber, plastics, paint and other industries, particularly iron oxide red primer with rust function, you can replace the expensive red lead paint, saving non-ferrous metals. High Ground material, for use in precision metal instruments, optical glass polishing. Powder metallurgy high purity is the main base for various magnetic alloy smelting and other senior alloy steels. By the one pack stabilizer  ferrous sulfate or iron oxide yellow, or scraps of iron mixed by high temperature calcination, or directly from the liquid medium is made.
5, red in the building materials industry, mainly for color cement, colored cement tiles, colored cement tiles, imitation glazed tiles, concrete tiles, colored mortar, colored asphalt, terrazzo, mosaic tiles, artificial marble and stucco walls, etc.; in the paints and coatings industry is mainly used to manufacture a variety of paints, coatings, inks. In other industries, such as ceramics, rubber, plastics, leather, pulp used to make arrangements light coloring agent and a filler

PVC heat stabilizers some of the important role

1 absorption and HCl, inhibit its catalytic automatically . Such stabilizers include lead salts , organic acids, metal soaps , organic tin compounds , epoxy compounds, amines, metal alkoxide and a phenolic salts and metal thiolate salt. They are available with HCl to de- HCl reaction inhibition PVC .
(2) replacement of PVC unstable allylic chlorine tin stabilizer  molecule or a tertiary carbon atom chlorine atom , inhibit de PVC. Such as organic tin stabilizer of PVC unstable molecule of chlorine ligand binding occurs , the ligand , organic tin substitution with an unstable chlorine atoms . 3 with the addition reaction of a polyene structure , damage the formation of a large conjugated system and reduce coloration . A salt of an unsaturated acid or ester containing double bonds , and the PVC molecules conjugated diene double bond addition reaction , thereby destroying the  Diethyleneglycoldibenzoate conjugated structure, and color.
 4 capture free radicals and prevent the oxidation reaction . Such as adding phenolic heat stabilizers can block off HCl, is due to give phenol H atom radical degradation of PVC macromolecules with radical coupling reaction with O2 to form a substance can not be , and has a thermal stability. Such thermal stabilizers may have one or several functions of both . Ideal PVC heat stabilizer should be a multi-functional substance , or a mixture of some materials , they can achieve the following functions:
1 replacement lively , unstable substituent such  titanium dioxide as attached to the tertiary Cl Cl atom or allyl chloride , to form a stable structure ;
(2) to absorb and process the PVC processing and release of HCl, HCl elimination autocatalytic degradation ;
 3 passivated on the degradation neutralized or catalytic metal ions and other harmful impurities ;
 4 by chemical reaction forms an unsaturated bond can block the continued growth inhibiting degradation coloring ;
5 The best protection against ultraviolet radiation shielding effect .

Aluminum sulfate coagulation wastewater treatment and wastewater treatment with

Aluminum sulfate as the coagulant , it is acidic chemicals, waste water can also be used as an alkaline pH adjustment chemicals . It is a traditional pharmaceutical wastewater , which  organic pigments both participate in the wastewater effluent coagulation treatment , and is also involved in wastewater treatment . We look at what is waste and wastewater coagulation treatment and disposal method .
Wastewater treatment aluminum sulphate coagulation coagulation wastewater treatment to waste water by adding coagulant ( such as aluminum sulfate , ferrous sulfate , etc. ) , dissolved alumina colloid, the colloidal substances in wastewater the fine coagulated or flocculated suspended solids are separated out water and solid contaminants , methods  Flame retardant to purify wastewater .
And wastewater treatment
And wastewater treatment method is the use of treated wastewater and the purification of the approach. The basic principle is to make the acidic wastewater plus the OH or H and the alkaline wastewater OH and H- plus interactions generate weak dissociation of water molecules , while generating additional soluble or insoluble salts, thus  PVC plasticizer eliminate their harmful effects. Obey the law of the reaction equivalent , can be processed using this method and recovered by using an acidic water and alkaline water , acidic or alkaline water can adjust the PH. The chemical treatment of sewage by chemical reaction action to remove the impurities , mainly in sewage processing target inorganic or organic ( difficult biodegradable ) dissolved substances or colloidal substances. Commonly used chemical treatment methods such as chemical coagulation , neutralization, chemical precipitation and oxidation-reduction method . In the coagulation of aluminum sulfate, ferrous applications are more extensive , and in the middle and the most widely applied method is lime , ferrous sulfate is also used for redox .

polyethylene wax (PE wax ) in the role of PVC pipe

Polyethylene wax (PE wax ) in PVC pipe Application : PVC pipe sections in the production , there will be not smooth and shiny is bad phenomenon.
Some people do use paraffin lubricant , but  heat stabilizer for foaming board the effect is not ideal. The use of polyethylene wax lubricant of PVC pipe sections have better results.
Paraffin wax lubricant as pvc , since a low softening point , good dispersibility , high temperature in the production process , basically the liquefied wax , evaporates into a gas in PVC pipe applications, the  calcium zinc stabilizer wax is difficult to play a role. Scattered ineffective, out of PVC pipe sections will have the surface stain .
Polyethylene wax (PE wax )
Polyethylene wax (PE wax ) produced PVC pipe profiles would not have such problems , because the softening point of the polyethylene wax itself is high , but at high temperatures, the polyethylene wax (PE wax ) but will become liquid , viscosity, polyethylene wax (PE wax ) poor dispersion , but the light is very good, polyethylene wax (PE wax ) , then a low viscosity , good dispersion , light can also.
Only pure polyethylene wax (PE wax ) production aluminum hydroxide  out of PVC pipe sections until smooth and shiny. Polyethylene wax containing impurities quality will be relatively worse .

Calcium stearate nature

Calcium stearate uniform fine white powder. Melting point 175 ℃, density 1.035g/cm3. Dissolved in toluene , ethanol, benzene and other organic solvents , insoluble in water . Slowly fluorescent brightener  heated to 400 ℃, decomposition, combustible , the case of decomposition of stearic acid and corresponding calcium salts . Water absorption, non-toxic.
Use heat stabilizers for PVC and a variety of plastics processing lubricant , release agent . In rigid products , and the base of lead salts , lead soap can increase the gelation speed. Also used in food packaging, medical equipment and other requirements nontoxic soft film and equipment. Can be made of polyethylene , polypropylene, halogen absorbent to PVC window stabilizer  remove the residual catalyst on the adverse effects of color and stability . As a plasticizer in rubber processing , make the whole into a natural rubber and rubber softening , and almost no effect on curing . Also used as a molding of polyolefin fibers and lubricants , grease thickening agent, textile waterproofing agent, paint flatting agent , when manufacturing plastic LP plasticizers. Also used in pencil manufacturing and pharmaceutical , perfume industry .
Action
Polyolefins polyolefin acid neutralizer and  blowing agent corrosion stability of the color is directly offered ; lubricating / processing aids improve the polyolefins, polyamides , styrene and rubber in the extrusion molding ( film, fiber , copying , etc. ) , and press molding processability. Release properties of the thermoplastic plastics , rubber, and thermoset articles, such as polyurethane foam
Unsaturated polyester

application performance organic pigments

Organic Pigments Industrial Technology Development and other industrial technology, its applications continues to expand, higher demands , prompting the related technology to the magnesium hydroxide flame retardant  deeper direction. Organic pigments its requirements can be summarized as follows: ① gentrification products that meet the metal coating durability, weather fastness , heat resistance, solvent resistance, and resistance to migration performance and other requirements ; ② organic pigments dosage of , the development of specific applications performance -specific products, such as water , oil , easy dispersibility , high transparency , heat resistance, excellent migration resistance new special formulations , having a high purity crystalline form of certain special features of the organic pigment.
  Applications department requirements to promote the rapid development of organic pigment industry technology , from classical organic synthesis reaction unit ( such as halogenation, nitration , reduction, condensation, diazotization, coupling reaction ) , filtration, separation, drying, grinding process gradually penetrate multidisciplinary areas  iron oxide black such as solid state physics chemistry, morphology, powder surface chemistry, interfacial chemistry , solid solution and crystal chemistry , polymer chemistry and powder dispersion technology. Which highlights the research focus for the development of new varieties of structural pigments , colored crystal particle surface modification treatment technology, efficient pigment dispersion technology , organic pigments and commercial processing technology and application performance testing and evaluation. ( A ) the chemical structure of the pigment new breed was developed to improve the durability of paint , heat stability, resistance to weather fastness , solvent stability and resistance to migration performance ; bright shade , high tinting strength yellow, orange , red, purple and brown varieties to meet with performance dacron blue, green, copper phthalocyanine pigment to match the requirements. The principal means of synthesis of new heterocyclic structure of the pigment , a good Acrylic processing aid  molecular planarity . Symmetry , with a specific substituent , change the molecular polarity , can form intermolecular hydrogen bonds , to improve heat stability and resistance to migration . Based paint durability ( light resistance, weather fastness , heat stability , solvent resistance and migration resistance , etc. ) of the level classification , grade ( high ) , or organic pigments HOP HGP (HighPerformanceOrganicPigments; HighGradePignents), has not only excellent application fastness properties , and value-added products , is high. Undoubtedly increasing organic pigment product formulations to meet specific application areas , high-performance requirements, will be an important trend in the future .

How to detect PVC stabilizer

1 hydrotalcite, organic auxiliary classes of organic compounds such as single-use type, the thermal stability is not good, often with a metal-containing heat stabilizer compound used. Currently used thermal stabilizers are organic polyols, phosphite, epoxidized soybean oil, 1,3 - dione. Polyhydric alcohol is the mechanism: generating a complex  plastic processing aid catalytic effect of chloride, thereby enhancing the effect of the thermal stability of metal. The most commonly used polyols are pentaerythritol, dipentaerythritol sorbic alcohol. Pentaerythritol heat stabilizer for calcium zinc thermal stabilization studied polyols for PVC processing performance. Organic phosphite heat stabilizer is the most important and the largest use one, when compounded with the metal soap is used, the effect is obvious. Commonly used are alkyl and aryl phosphites. Epoxy oils has attracted more and more people's attention, such compounds are characterized by a molecule containing one or more epoxy groups, PVC heat generated when hydrogen chloride, an epoxy group to quickly react with , blocking the hydrogen chloride from the catalyst for PVC, thereby improving the thermal stability of PVC. As the epoxy oils of PVC has a strong plasticizing action and non-toxic, in recent years, many such as food packaging for soft cork bottle plasticizers and heat stabilizers. Wu Maoying other studies β-diketone compound and zinc heat stabilizing effect, that the β-diketone complexes of zinc with excellent thermal stability performance. PVC heat stabilizers organic research is entering the 21st century one of the hot variety of organic compounds and their derivatives stabilizing effect on PVC, typical substances vanillin - Schiff base, barbituric acid, etc. These organic has titanium dioxide anatase  excellent thermal stability. In addition to the organic auxiliary heat stabilizers, thermal stability of the PVC industry, hydrotalcite, synthetic zeolites, and other inorganic perchlorate also used in supplemental heat stabilizers. Hydrotalcite layered inorganic metal material, its molecular formula is: water of crystallization with both a conventional synthesized by coprecipitation method. When a hydrotalcite is used as heat stabilizers for PVC, and PVC processing can be released during the degradation reaction of hydrogen chloride, when the hydrotalcite is used alone as heat stabilizers for PVC, the effect is not ideal, and a metal soap compound generally used. Hydrotalcite obvious disadvantage is poor compatibility with PVC, in recent years, different researchers by reducing the size of the hydrotalcite to improve their dispersion in PVC or molecular modification hydrotalcite enhance compatibility. Synthetic zeolite molecular sieves or more types of structure of the compound, usually containing oxides of silicon and aluminum composite, also contain water of crystallization, the molecule containing regular pore structure. In recent years, zeolite PVC industry as a heat stabilizer also been studied and used. Using an oil bath pot, built glycerin, will be tested PVC heat stabilizers mixed with the material after being loaded into a small test tube, so that the material becomes a slight concussion and firm, and then placed in an oil bath pot among glycerol oil bath pot set in advance a temperature of approximately 170 ℃, PVC material within the small tube and the upper surface of the upper surface level of glycerin, small tube top, with a thin tube inserted into the plug, the upper and lower transparent glass, the glass tube Congo red paper hit the bottom of the roll inserted so Congo red paper with the lower edge of the upper edge of the PVC material is located about 2 cm. Record the test tube to the test tube from Congo red paper turns blue start time is the thermal stabilization time. When the PVC at about 170 ℃ the temperature, will decompose rapidly, but the addition of the heat stabilizer, suppresses the decomposition, with time, the heat stabilizer consumption occurs when the consumption is completed, PVC drastically stars explain the release of HCl gas, this time, the test tube as Congo Red reagent reacts easily with HCl discoloration, immediately apparent, recorded at this time time, by the length of time to judge the merits of the effect of heat stabilizers. 2.2 Preparation of the static oven test in addition to thermal stability of PVC powder and other agents other processing aids (such as lubricants, impact modifiers, fillers, etc.) of the high-speed mixed sample. The sample must be taken, according to certain proportion of different thermal stabilizers, after mixing, add to the double-stick kneading machine for preparation of test pieces, generally without the addition of a plasticizer in the case, two roll temperature is set at 160 ~ 180 ℃, adding a plasticizer, the roller temperature is generally about 140 ℃. Tabletting using two stick repeatedly to obtain a uniform film after the backsheet, and clip, a certain size with different samples PVC heat stabilizer. Different PVC sheet placed in a test fixture, and then placed at constant temperature (180 ℃) of the oven at regular intervals (eg 10 min or 15 min), to record the color change of the test piece until the black so far. An oven aging test, can determine the thermal stability of PVC heat stabilizer effect to the merits, particularly ability to inhibit the color change is generally believed that, PVC heat, the color will occur white - yellow - brown - brown - black range from shallow deep changes, through a certain period of time to determine the color of PVC degradation. Torque rheometer torque rheometer is an imitation of the actual PVC processing of a typical small pilot-type apparatus. Torque Rheometer advance the set temperature, when the temperature rose to specify and steady speed, will be weighed mixture added processing chamber, quickly closed records on a computer connected to a variety of parameters, namely flow curve. After processing, you can also get different extrudate physical characteristics, such as whiteness, whether shaping, smoothness and so on. These parameters can determine the corresponding potential industrial heat stabilizers, heat stabilizers suitable shall have suitable torque and plasticizing time of the extrudate should be preferably molded and  PVC stabilizer for pipe whiteness, surface smoothing. Torque rheometer in laboratory studies and between industrialized mass production to build a convenient bridge. 2.5 blackened roll as a dynamic measurement test the effect of a thermal stabilizer class helper methods, dynamic rheometer double roll is used in the absence of experimental double-rolled sheet, select the instrument, which will be combined with high-speed mixed powder, pressed sheet forming, the resulting samples were subjected to repeated extrusion until the black test piece until completely black record time, the time is called blackening. Blackening by comparing the length of time to determine the type of thermal stabilizer effect of the thermal stability of PVC. Shelf element according to the design requirements can be adjusted within a certain range; isomorphous substitution can also be introduced by other metal atoms, such as the host layer alkaline. Synthetic hydrotalcite with other thermal stabilizer compound as PVC heat stabilizer, can significantly increase the thermal stability of PVC, PVC material may also be given a number of other excellent properties, which is due to the hydrotalcite has a unique structure and properties. Hydrotalcite Mg-Al layered double hydroxides right through the base of PVC rigid and lightweight thermal stability, introduced the stabilizer coprecipitation synthesis method, and characterized by X-ray diffraction analysis and thermal gravimetric analysis; The results show that the new type heat stabilizers have important environmental value and economic benefits. TGA studied hydrotalcite, lead salts, organic tin, as well as hydrotalcite and lead salts, organic tin compound stabilizers for PVC composite stabilizing effect was investigated lead salt stabilizer system and hydrotalcite stabilizing system with an organic tin compound mechanical properties of PVC and rheological properties. The results showed that: hydrotalcite can not be the primary stabilizer of PVC, it should only be a secondary PVC stabilizer or stabilizer compounded with other compound stabilizers for use ratio of Mg 2 DLHs effect on the thermal stability of PVC most Jia, respectively, and lead salts hydrotalcite, organotin compound were carried out with good synergies and the latter better stability of PVC. Which, PVC, hydrotalcite and organic tin compound to 100:1.5:1.5 mass ratio of thermal stability of the composite system is not only superior to the conventional lead salt system, with good mechanical and rheological properties. Under suitable conditions, synthesized by coprecipitation Mg-Al hydrotalcite series products. Mg-Al-based hydrotalcite adjustable main characteristics of the chemical composition of shelves, first explores the Mg-Al-based hydrotalcite-doped calcium possibilities. The flame retardant and smoke suppression function of calcium into the main body of Mg-Al hydrotalcite chemical composition of laminates, laminates replace some or all of the magnesium ion, achieved through the experimental study of calcium magnesium aluminum layered product type three metaclasses and calcium aluminum hydrotalcite Bivariate Hydrotalcite synthesis. Using XRD, FT-IR on their composition and structure were characterized. XRD results that the samples are synthesized hydrotalcite layer structure, good crystal, high purity. I synthesized samples interlayer anions are good symmetry of CO32-, further confirmed the Ca / Mg / Al Hydrotalcite successful synthesis. First studied as a flame retardant, heat stabilizer in PVC applications. Experimental results show that the Ca / Mg / Al hydrotalcite can improve the thermal stability of PVC. Under comparable conditions, MgAl-CO3-LDHs flame retardant and smoke suppression performance than Al (OH) 3 and Mg (OH) 2. At the same dosage (20phr) case, calcium magnesium aluminum type ternary Mg-Al hydrotalcite exhibited than hydrotalcite and hydrotalcite-type calcium aluminum better flame retardant and smoke suppression performance, indicating Ca2 + has improved materials flame retardant and smoke suppression effect.

[ FWA ] diamond fluorescence intensity grading

The fluorescence intensity of the diamond grading , the following is zakaly Xiaobian for you to collect relevant information , hoping to help you. Zakaly same diamond , cheap half. Zakaly jewelry electrocution 8 years, he used the Internet information technology to one pack stabilizer  optimize diamond jewelry supply chain , to overturn the traditional diamond sales model, drained the last drop of diamond profits . for the public to create a "low price", " high quality" , "credibility " shopping platform .
Approximately 50 % of the diamonds in the ultraviolet radiation will produce fluorescence, diamond fluorescence color, intensity of the diamond 's appearance ( body color ) have a certain influence , and sometimes even affect the price of diamonds , which is the fluorescence intensity of diamond grading significance diamond Fluorescence most common color is blue and white , followed by yellow and white , yellow, green , orange and other colors. above with moderate-intensity blue-white fluorescent colorless diamond will look more white, such as "Jager diamonds" strong blue- white fluorescent light yellow diamonds also available with yellow body color complementary , looks nearly colorless , improved color grade diamond if diamond yellow fluorescence , in any case will cause lower color grade diamond . too strong fluorescence also diamond will show hazy oily , reducing the transparency of the diamond , affecting the clarity of the diamond , such as the "Pre mier ¨ ultra Blue Diamond fluorescence also many jewelers to create a sense of mystery and surprise .1 fluorescence intensity of the fluorescence intensity level ( flourescence degree) is a diamond in the long visible under UV irradiation intensity level . China's " diamond grading " standard, the diamond 's fluorescence intensity level is divided into strong , weak , no four grades . CIBJO also put fluorescent level is divided into four grades . GIA is classified as strong , strong , weak , no five levels .2 fluorescence intensity of the Impact modifier for PVC  fluorescence intensity grading grading method is the use of visual methods in the long UV , compared to standard fluorescent intensity like stone, the fluorescence intensity of the diamond grading . fluorescence intensity of the sample (masterstone flourescence degree) refers to a set of calibrated fluorescence intensity level standard round brilliant cut stone like cobalt stone . usually consists of three components , in turn, representative "strong" , "medium" , "weak" three levels lower . following steps: ( a ) the fluorescent sample by strong, medium and weak order, from left to right in the ultraviolet fluorescent lamp placed equidistant black box . ( 2 ) open length ultraviolet light switches . ( 3 ) to be graded diamonds gripping tweezers , place the UV fluorescent obscura in comparison with the fluorescence intensity of the sample to determine the fluorescence intensity level .3 . fluorescence intensity level division rules
( 1) If the diamond to be graded higher than the fluorescence intensity of the fluorescence intensity of the comparative sample in the " strong '', still with the" strong " indicates the fluorescence intensity level of the diamond (2 ) when the classification of the diamond to be less than the fluorescence intensity of the fluorescence intensity of comparative sample in the " weak" , the use of " none" represents the level of fluorescence intensity of diamond (3 ) subject to a grading diamonds and a fluorescence intensity vs. the same sample , the level of fluorescence intensity of the fluorescence to be graded diamond intensity level . ( 4 ) to be graded diamonds fluorescence intensity between adjacent two contrast between samples , the lower -level representatives to be graded diamonds fluorescence intensity level . ( 5 ) the same fluorescence intensity of the diamond , the fluorescence intensity on there are slight differences. ( 6 ) in addition to the fluorescence intensity magnesium stearate  to be marked , the need to mark the fluorescent colors.
The fluorescence intensity of the diamond is a diamond grading report content , can not be compared with the color grading . Commercially, high color grade (H colors or more ) , high clarity (VS and above ) if diamonds have medium blue and white fluorescent its price is often lower than the non-fluorescent diamonds 1010 to 10%, the fluorescence is stronger, the greater the impact on prices , while slightly yellow diamond (I color less ) than if a medium blue and white fluorescent , can increase up to 4% weak fluorescence and low clarity diamond fluorescence little impact on prices . diamond prices with yellow fluorescence can often save 5 % to 10% , but the real diamond trade , few people put a fluorescent and non-fluorescent diamonds detailed separately . therefore fluorescence actual impact on diamond prices significance,

PVC impact modifier types Introduction

PVC impact modifier and sometimes also from the plasticizing effect , it can also be seen as a plasticizer for PVC resins and impact modifiers are the following : ( 1 ) chlorinated polyethylene (CPE ) is the iron oxide black  use of HDPE in the water phase of the powdery product by suspension chlorination , so as to increase the degree of chlorination of HDPE original crystals become amorphous elastomer. Used as a toughening agent C? E, containing 25-45 % amount is generally C1 . CPE wide source of low price, in addition to a toughening effect , but also has a cold resistance, weather resistance , flame resistance , and chemical resistance . At present in China is dominated by CPE impact modifiers , especially in the production of PVC pipes and profiles , most plants use CPE. Generally added in an amount of 5-15 copies. CPE can be used in conjunction with other plasticizer , such as rubber , EVA , the effect is better, but even in aging rubber additives .
(2) ACR is methyl methacrylate , acrylate monomers , ACR is best developed in recent years, impact modifiers , which can increase the impact strength of the material several times. ACR core-shell structure is an impact modifier , methyl methacrylate - ethyl acrylate composition of the shell polymer , crosslinked acrylic or butyl rubber elastic body is formed as the core of the particle distribution of the inner segment . Particularly suitable for outdoor use PVC plastic products, impact-modified PVC plastic window profiles used in the ACR as impact modifiers and other modifiers processing performance compared with the smooth surface, good aging resistance , high strength welding angle characteristics, but the price CPE, high 1 /3. Common foreign brands such as K-355, the general amount 6-10 copies. The current domestic production of the manufacturers ACR impact modifier fewer manufacturers use less.
(3) MBS is methyl methacrylate , butadiene and styrene copolymer of the monomers . MBS between the solubility parameter of 94-9.5 , with PVC solubility parameter close, so when the good compatibility with PVC , its most important feature: After adding PVC products can be  tio2 anatase made transparent . Generally added in PVC 10-17 parts of PVC , the impact strength can be increased 6-15 times, but the MBS in amount more than 30 parts , PVC impact strength decreased. MBS itself has a good impact resistance , good transparency , light transmission rate of 90 %, and to improve the impact resistance while other properties of the resin , such as tensile strength , elongation at break little effect . MBS higher prices , often with other impact modifiers, such as EAV, CPE, SBS , etc. and use . MBS poor heat resistance , weather resistance , not suitable for long-term outdoor use made ​​products, generally do not do plastic doors and windows profile production impact modifiers .
(4) SBS is a styrene -butadiene- styrene block copolymers, also known as thermoplastic rubber, thermoplastic elastomer part , the structure can be divided into star and line two kinds. SBS ratio of styrene to butadiene is mainly 30 /70, 40 /60 , 28 / 72 , 48/ 52 several. Mainly used as HDPE, PP, PS impact modifiers in an amount 5-15 parts . SBS primary role is to improve the low temperature impact resistance . SBS poor weather, not suitable for long-term outdoor use made ​​products.
(5) ABS is a styrene ( 40% -50 % ) , butadiene ( 25% -30 % ) , acrylonitrile ( 25% -30 % ) terpolymer used mainly plastic , PVC is also used impact modified , low-temperature impact modifiers also very effective. ABS is added in an amount of 50 parts , PVC , the  PVC heat stabilizer impact strength can be quite pure ABS . ABS is generally added in an amount of 5-20 parts , ABS poor weather , unsuitable for long-term outdoor use products, generally do not do plastic doors and windows profile production impact modifiers .
(6) EVA is an ethylene vinyl acetate and acid copolymer, vinyl acetate changed into a crystalline polyethylene , vinyl acetate content of a large difference , and the different refractive index EVA and PVC , transparent products is difficult to obtain , therefore , often the EVA resin and used with other impact . EVA dosage of 10 parts or less .

flame retardant: flame retardant polypropylene and trends

 
Describes the polypropylene (PP) flame retardant type and mechanism of resistance ene agent PP summarized research progress and trends. Efficient, low toxicity,
Low smoke, low cost, versatile, new composite "green" flame retardant PP 21st century focus of the study.
Polypropylene (PP) is a hydrocarbon material, heat of combustion, it is not entirely produced by burning smoke and toxic gases, its application is limited. In order to improve flame retardant PP, broadening its field of application, you must add flame retardants.
A, PP fire retardant classification
PP flame retardant more categories, according to the basic performance is divided into inorganic and organic flame retardants; according to high and low molecular weight divided into low molecular weight and high molecular weight flame retardant; divided by use of additive flame retardant and reactive flame retardant. Which, by the use of method of classification is more commonly used classification methods. Flame retardant is added to the polymer processing with flame retardant liquids or solids, including phosphates, halogenated hydrocarbons such as, the advantage of ease of use, wide applicability; reactive flame retardant is contained Cl,, Br, P and other elements and reactive flame retardant class of compounds, are copolymerized with the resin to give a resin flame retardant.
Two, PP flame approaches, methods and mechanism (a), flame route
PP flame retardant mainly through three kinds of ways to achieve [1]: (1) using the additive flame retardant, the flame retardant added by mechanical mixing
To the polymer, to achieve flame purposes; (2) use of reactive flame retardant, the flame participate in the reaction as a reactive monomer,
Grafted to the polymer main chain or side chain, the modified polymer has a flame retardant; (3) a flame retardant polymer itself. (Two), the basic method of flame retardant
Retardant PP basic method comprising: (1) use of foam or non-foam refractory material coating the surface of PP material, to
With oxygen or thermal isolation; (2) through the modification of the modified PP matrix material flame retardant. The second method is the main method. (Three), flame retardant mechanism
1. Termination of a chain reaction mechanism
PP combustion, the general decomposition of hydrocarbons. Further oxidation of hydrocarbons at high temperatures, decomposition of free radical HO •. HO • The chain reaction
Makes the flame should continue. Halide decomposition of hydrogen halide (HX). HX can capture high-energy HO • and produce X • and
H 2O, while X • R • reacts with the polymer and the HX, but also capture the HO •. This cycle enables highly active HO • Less
Less will eventually contribute to the ripple cut HO • terminate hydrocarbon combustion flame to achieve the purpose. For PP, halides
Usually without the use of fluoride chloride or bromide or iodide. Because fluoride too lively, the formation of molecular fluorine and very stable
Iodine forming compound is unstable, it is rarely used.
2. Mechanism of protective film
Flame temperature in the combustion swells into a layer of non-combustible protective film covering the surface of the material, isolated from the air and fire retardant. In
Phosphate flame retardant in the PP phosphate, halogen hydrocarbon ester. They differentiate to form a layer of porous insulating film coke, separated
Absolutely air to prevent heat transfer, and thus play a role in flame.
3. Cooling mechanism
Flame retardant polymer surface can melt at a lower temperature, the latent heat absorbed or endothermic reaction, consume a lot of heat, from
And to prevent burning. Such as Al (OH) 3 can play in PP flame retardant effect. It is a non-flame-retardant filling aids. When the temperature
No more than 200 ℃, hydration molecules and Al (OH) 3 combined with very strong, even at 230 ℃ for continuous heating will not significantly decompose.
When the polymer is exposed to heat, one of the Al (OH) 3 hydrated plays the role of heat. When the temperature is higher than 250 ℃, the polymer combustion,
Al (OH) 3 decomposes to absorb a lot of heat, and generate water. Water vapor, and absorb a large amount of heat, thereby reducing the polymer
Temperature of PP pyrolysis gas combustion products, the speed is very slow, less than the concentration of combustion can be maintained, thereby preventing burning. Mg (OH) 3 and Al (OH) 3 is similar, but its decomposition temperature close to 350 ℃ PP is a good flame retardant effect.
4 synergy system mechanism (1) Antimony - halogen collaborative system
Antimony compounds are commonly used Sb 2O 3, halide is an organic halide. Its mechanism is Sb 2O 3 and HX, generating SbOCl; SbOCl
Thermal decomposition of SbCl 3. First, SbCl 3 can be a long stay in the combustion zone, dilution flammable gas, isolated from the air, from the
To flame retardant; secondly, to capture combustible radicals H •, HO •, CH 3 •, etc., play a role in suppressing the flame; thirdly,
SbCl 3 in flames over condenses into droplets type solid particles, the wall effect reactive scattering a lot of heat, so that the combustion slows down or stops,
HX it off after the formation of the polymer of the unsaturated compound to form a crosslinked polymer, improved thermal stability. (2) phosphorus - halogen collaborative system
Phosphorus - when used in conjunction with each other halo promote decomposition, the decomposition temperature lower flame, accelerated decomposition of flame, burning
Region is formed more strongly phosphorus halide compound and decomposition products, and the resulting gas can stay a long time in the combustion zone, to form a strong
Gas barrier layer, to achieve the purpose of fire. (3) phosphorus - nitrogen coordination system
Phosphorus - nitrogen-based flame retardant mechanism by thermal decomposition, releasing acid and nonflammable gas, in which the dilution air
Oxygen. Nitrogen-containing compound plays the role of a blowing agent and coke enhancer, and phosphoric acid is the coked catalyst for burning surface
Forming a layer of porous coke protective film, heat insulation and oxygen barrier effect, can interrupt the burning chain reaction.
Three, PP flame retardant research
Phosphorus - Bromine flame retardant system has a higher melting point, heat resistance and light resistance, their synergistic effect with. This class is used more flame retardant tris (2,2 - dibromo-3 - bromo-propyl) phosphate (TOBP). Bromine and Sb 2O 3 on the ratio of phosphorus -
Bromine flame retardant composites greater impact. Add appropriate amount of chlorinated polyethylene flame-retardant properties of the PP material is small, but it can serve to improve the impact strength. Pengzhi Han and other studies TDBP and TDBP mixed with Sb 2O 3 on PP flame retardant
And rheological properties, and found that they have a significant synergistic flame retardant effect, and PVC heat stabilizer for fittings  its rheological behavior is affected by temperature, shear rate
Rate and flame retardants greater impact.
Intumescent flame retardant polymer technology is in the mid-1970s, the development of a new type of flame retardant technology. It will contain
There are carbon, acid source and air source intumescent flame retardant additives and polymer blend processing, the formation of flame retardant materials. Intumescent flame retardant to
Former multi-ammonium polyphosphate (APP), polyols and melamine composite component composition. When APP thermal decomposition when generated with
Dehydration of the phosphoric acid and pyrophosphoric acid, the polyol esterification, dehydration carbonization, and ammonia produced by the reaction with water vapor to form a
Layer of porous carbon layer, the carbon layer expansion reached retardant purposes. The disadvantage of multi-retardant, impact PP performance. Researchers
The system was modified. In order to ammonium polyphosphate based intumescent flame retardants, triazine derivatives and triazine ring-containing polymer
Due to its excellent flame retardant material synergies attention has been paid, it is flame retardant technology research and development of a hot spot.
Liao Kairong etc. [7] found that adding a small amount in PP triazine derivative flame retardants, can greatly improve the PP flame retardant;
It was also found in a single hydroxyethyl melamine polyphosphate compound and composition of the best flame. Ma collar, etc. [8] studied with P 2O 5, pentaerythritol and melamine for raw materials intumescent flame retardant (IFR), 3 kinds of functions of the PP as IFR / PP body
Department of coupling agent on the mechanical properties, morphology and rheological properties, that the coupling agent and PP blends, because both
The same crystal structure, can be copolymerized, is conducive to the improvement of compatibilizer. The one kind of intumescent accelerator
Join APP / pentaerythritol intumescent flame retardant, as the PP, flame retardants. This new technology greatly improved flame retardant
The flame retardant effect of PP, limiting oxygen index is improved. By heat treatment and melamine ammonium polyphosphate
Mixture to obtain high thermal stability and low moisture absorption intumescent flame retardant. He believes that high temperatures, with the melamine modified
PP polylactic acid promotes the inganic pigments  combustion heat generated during the oxygen-containing organic compound and the unsaturated organic compound charring. Since
Expanding carbon layer shielding effect, so the accumulation of coke carbon layer phosphate favor of further carbonization coke material to accumulate in the melt
The surface of the oxygen-containing compound of phosphorus to form an acid layer have a barrier effect of the air.
Chiu et al [11] studied the halogen-containing flame retardants, flame retardant effect is very significant, but the large amount of smoke when burned, produces a large number of corrosive
Gases and toxic gases, causing environmental pollution, its application is limited. Halogen-free flame retardants less pollution, rapid development.刘敏江 etc.
Using red phosphorus, magnesium hydroxide, APP, pentaerythritol, melamine-halogen flame retardant, various flame retardant composition system,
Flame of PP conducted research and found that APP, pentaerythritol, melamine, between the red phosphorus flame retardant has a good synergy
Purposes. Retardant reduced tensile strength of PP, with the increase of flame retardants, increases the degree of tensile strength is reduced,
Can be reasonably complex between flame retardant synergy play.
Studied intumescent flame retardant system of PP retardant synergistic effects and the impact of liquidity,
The results show that: Collaborative Retardant PP significantly improved flame retardant properties, the droplet phenomenon completely overcome, suitable
Phosphorus, carbon, nitrogen ratio is the formation of high-quality carbon layer of assurance, smoke suppression effect significantly, significantly improved melt flow PP flame retardant system
Sex. Use Intumescent Flame Retardant for PP modified to solve the difficult process operation retardants, stable production
Poor two problems. Halogen-free flame retardant engineering plastics can improve universal value after broaden its function, but also conducive to
Environmental protection, is a promising flame retardants.
Cui Yan et al] studied the different flame retardants, different melt flow index of PP and PP flame retardant properties of inorganic fillers on the impact of
Ring, the results showed that those who make the melt flow performance degradation factors make PP flame retardant performance.
M double hydroxide composite metal oxide complex with APP, for polyamide 6/PP blends to produce good synergistic flame-retardant effect
Fruit. Metal catalyst to improve flame retardant effect of the flame retardant expanded applications. Mn and Zn compounds as
APP / pentaerythritol / PP catalyst intumescent flame retardant system, the other divalent metal ions can be generated in the APP intermolecular crosslinking
While releasing ammonia and H 2O. Four, PP flame retardant trends (a), halogen-free flame retardant and intumescent flame retardant
Currently, more commonly used non-halogenated flame retardants and inorganic flame retardants are intumescent flame retardant. Intumescent flame retardant is a new non-halogen flame retardant. Because of its low smoke when burned, and the generated gas discharge harmless carbon layer can effectively prevent the polymer droplet,
Suitable for PP flame retardant, so intumescent flame retardant research at home and abroad more and more attention, and has broad hair
Exhibition (two), triazine derivatives mainly nitrogen compounds
Triazine derivatives with a nitrogen-containing compound as an expansion-based flame retardant system in the  processing aid new charring agent, has been shown to provide
High intumescent flame retardant effect has significant synergies. It is halogen-free, low toxicity, high decomposition temperature, suitable for processing,
Little effect on the mechanical properties, no bleeding, excellent flame retardant properties, the starting material activity, can be a group with a compound containing different anti-
Should synthesize a variety of high melting point compounds. It is intumescent flame retardant system research and development focus.
(Three), inorganic flame retardants
Inorganic flame retardant non-toxic, non-corrosive, does not cause secondary pollution when burned, some better than organic flame retardant high temperature.
With the improvement of environmental requirements, but also the future development of inorganic flame retardants development of a trend. Especially for some flame retardant
Modified by [such as the use of silane coupling agent on the Al (OH) 3 surface modification] to improve flame retardant properties, has a broad development
Space.
(Four), polymer / flame retardant nanocomposites
(Five) synergistic flame retardant system
Synergistic flame retardant system combines the respective excellent performance, good effect, low cost, can be both flame and smoke suppression. It can be flame retardant compound, to reduce the flame retardants, the purpose of improving flame retardancy.
Six), other types of flame retardants
Enhanced dust-retardant (such as a halogen - antimony concentrated, capsule, wet body, etc.) of, reduce environmental pollution. The future development of non-dust flame retardants are one of the hotspots. In addition, high efficiency, low toxicity, low smoke and flame retardants and to improve compatibility with the base resin research is the development trend of flame retardants.