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.

some of the main principles of the processing aid for processing

1, the role of the principle of PVC processing aids melt due to poor scalability, easily lead to melt broken; PVC melt relaxation slow, easily lead to the product surface rough, dull and shark skin and so on. Therefore, processing often requires the addition of PVC processing aids to improve the melt processing aids described above is the lack of processing performance can be improved resin additives, and its main role in three ways: to promote the molten resin to improve the rheological properties of the melt lubrication and promote the molten resin to give: PVC resin in the WSD PVC flame retardant  heated state, when the shear force under certain melt processing modifier first melted and adhered to the surface of the PVC resin particles, its compatibility with the resin and Its molecular weight, the viscosity of PVC and increasing the friction, and thus the shear stress and the effective heat transfer to the PVC resin, melt rheology improving the acceleration performance of the molten PVC: PVC has a melt strength is poor, poor ductility, and melt fracture shortcomings, and to improve the melt processing of said modifier rheology. Its mechanism of action: Increase the PVC melt viscoelasticity, thus improving the die swell and melt strength gives improved lubricity: PVC processing modifier is compatible with the first portion of the melt, plays the role of promoting the melt; but not with PVC Compatible part WSD Polyethylene wax  migrate to the outside of the molten resin system, thereby improving the releasability of the copolymer 2, a conventional processing modifier ACR ACR methyl methacrylate and acrylate, and styrene monomers. In addition to be used as a processing aid, it can also be used as impact modifiers. PVC plastic window profiles or generally used ACR201 ACR401, in an amount of 1.5-3 parts of a modified impact modifier polymer content is important to improve the impact resistance, PVC resin is a non-polar high crystallinity there is a strong interaction between the oligomer molecule, is a hard and brittle material; low impact strength. After the addition of impact modifiers, elastomeric impact modifier particles can be raised to reduce the total stress crazing and  WSD zinc stearate its particle deformation and shear band and prevent crazing expansion and growth, absorb the impact of the transmission of the body material able to achieve the purpose of impact. Small particle modifier to facilitate increasing the number of unit weight or unit volume of a modifier to increase the effective volume fraction, thereby enhancing the ability of stress dispersion. Currently used widely for organic impact modifier.

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.

types of plastic flame sense

Plastic inexhaustible extended use category while its volume increases and flammable and easily ignited a fever , brought to mankind unexpected danger and loss . Began as a flame retardant additive major categories beginning in chemical fiber, plastics industry projections . Brominated flame retardants despite heavy smoke , because of environmental problems by  Glycrin monostearate the EU restrictions ; But since retardant properties, and with less impact on product performance is small, quite a long time thereafter remain within the main flame . Tips progress along the international growth of brominated flame retardants new features is a continuous and progressive increase of bromine content (fèn) molecular weight . Most phosphorus flame retardants (dū) is a liquid , mainly used for PU, PVC and other plastics . Small molecule phosphorus flame retardant main problems are volatile , high heat resistance is not high , now is trying to develop a large molecular weight compounds and oligomers , special suitable for casting finished and soft PU foam guessed . Flame retardant and plasticizer , flame retardant and cross-linked multi- phosphorus flame retardant effect acrylic processing  of the growth is another major aspect is the low temperature flame-retardant plasticizer special probation plasticized PVC is mainly used in the finished product , such as domestic cumene produced two phosphate. Flame number which reflects the activity of the crosslinking agent is a phosphorus-containing polyhydric alcohols , not only as a reflection type flame retardant PU , and also with the brominated flame retardant and used epoxy resin , brominated flame retardant can be greatly reduced dosage . Since phosphorus flame retardant but also to the low toxicity of growth , not only to solve their toxic products , but also to consider the toxicity of the combustion product differentiation and waste pollution problem situations , or even appropriate, production, sales , storage and transportation process (dì) toxicity problems. Aluminum hydroxide usually with a silane coupling agent , titanate coupling agent and stearic acid ( salt ) , etc. before disposal , just started this titanium dioxide  country , foreign countries have been further carried out before the new special effect modifier of aluminum hydroxide open up. Solem new technology company with a silane disposal and disposal of organic silicone coated aluminum hydroxide , in the PP, PE is added to 70% volume of 60 processing still very good , and the physical properties and flame retardancy of progress.
Inorganic synergist new varieties. A small amount of aluminum hydroxide flame retardant synergist can fill data function has obvious improvements , such as restraint dripping , improved mechanical properties . And aluminum hydroxide can play a synergistic role in a wide scope of an inorganic flame retardant synergist , mainly metal oxides and zinc borate , phosphorus-based compound ( red phosphorus , phosphate) , a silicon -based compound, a metal nitrate ( copper nitrate , silver nitrate ) , ammonium polyphosphate , etc. .

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 soap component analysis of some of the key

Aluminum sulfate: white shiny crystals, granules or powder. Sweet. Stable in air. 86.5 ℃ when the loss of part of the crystal water, 250 ℃ lose all crystal water. Violently expanding when heated and become a sponge-like material. Thermal decomposition of red burn sulfur trioxide and aluminum oxide. When the relative humidity of about 25% lower weathering. Soluble in water, practically insoluble in ethanol, the solution is acidic. Long after boiling insoluble basic salt precipitation. The relative density of 1.62. Aluminum sulfate is a widely used industrial reagent, usually yellow iron oxide  with alum (potassium aluminum sulfate dodecahydrate both) confusion. Aluminum sulfate is often used as flocculant for purifying drinking water and wastewater treatment equipment which is also used in the paper industry. Aluminum sulfate application: 1. Papermaking industry as paper sizing agent to enhance water-resistant paper, anti-seepage performance; 2 dissolved in water to make the water and natural rubber fine particles agglomerate into large floc was thus removed from water, the coagulant for water and wastewater; 3 as turbidity purification, also used as a precipitating agent, fixing agent, fillers and iron oxide black  the like. Used in cosmetic antiperspirant cosmetic ingredients (astringent); 4 Fire industry, and baking soda, composed of foam blowing agents; 5. Analytical reagents, mordant, tanning agents, oil bleaching agent, wood preservative agents; 6 pasteurized albumin stabilizer (including liquid or frozen whole eggs, egg yolk protein or); 7 can be used for raw material for the manufacture of artificial stones and advanced ammonium alum, aluminates other; 8. fuel industry , in the production of chrome yellow and color lakes made the  plastic processing aid precipitating agent, and a filler while underway fixing role. Preparation of aluminum sulfate: pressurized by the bauxite and sulfuric acid reaction. Or sulfuric acid decomposition alunite, kaolin and alumina containing silicon material can be obtained. Aluminum sulfate can also be aluminum hydroxide (Al (OH) 3) into sulfuric acid (H2SO4) is prepared. 2Al (OH) 3 + 3H2SO4 + 10H2O → Al2 (SO4) 3.16 H2O 1. Crystallized from the resulting acidic solution of aluminum sulfate hydrate crystals slowly heated, it gradually dehydrated, and finally the temperature was raised to 350 ℃, is completely Dehydration as anhydrous aluminum sulfate; 2 sulfuric acid method: pulverized to a particle size of bauxite, the addition of sulfuric acid to the reaction vessel and the reaction solution after sedimentation, the supernatant adding sulfuric acid to neutral or slightly alkaline, and then concentrated to about 115 ℃, solidified by cooling, crushing prepared products.

PVC lubricants narrative

PVC processing is an essential lubricant additives . Add appropriate amount of lubricant in PVC can reduce PVC and PVC particles before melting melt friction between macromolecules ; reduce PVC melt and the plastic flame retardant  friction between the contact surfaces of plastic machinery . Amount of lubricant can improve the PVC melt flow , improve production efficiency and to prevent friction and heat caused by PVC degradation and improve product appearance. Press the function can be divided into external and internal lubricant lubricants. PVC to poor external lubricant , the resin inside the melt easily migrate to the surface, forming a lubricant interface layer , thereby reducing the P PVC particles melt prior to melting the plastic mechanical friction between the contact surfaces . Lubricants containing a polar group , and has good compatibility with PVC , PVC can reduce intermolecular forces , reduce melt viscosity and improve the melt fluidity .
Lubricant inside and outside of the titanium dioxide  points only relatively speaking , there is no strict criteria for the classification . In a different polarity resins , internal and external lubricant may change .
Such as stearic alcohol, stearic acid amine, butyl stearate , and stearic acid monoglyceride the polar resin ( such as PVC and PA) made ​​, from the internal lubrication, but for non -polar resin ( such as PE
, PP) , the external lubrication effect is displayed . In contrast , polymer with polar resins such as paraffin poor , such as in polar
PVC is used as external lubricant , and the PE
, PP and other non-polar resin was internally lubricated
Agent. At different  processing  titanium dioxide temperatures , inside and outside will change the role of a lubricant such as stearic acid and stearyl alcohol are used in PVC calendering initially, as the processing temperature is low, and PVC
Compatibility is poor, mainly from outside the lubricating effect, when the temperature rises, increases compatibility with PVC , then transformed into an internal lubricant effect.