PVC processing aids Actual funtion

PVC processing aids are the main raw materials for acrylic esters and methyl methacrylate. In the actual production, usually the first acrylic and other monomers (such as styrene, acrylonitrile, etc.) by emulsion polymerization to form a glass transition temperature of the polymer, that is, with the elastic properties of the core, and then with methacrylic acid Methyl ester, styrene and the like to form a polymer having a core-shell structure. The emulsion solid content of this emulsion polymerization is generally about 45% ± 3%, the emulsion and then dehydrated to make the product less than 1% water content (mass fraction), to obtain white powder products.

Core-shell emulsion polymerization is the core of ACR resin production technology. Although the core structure of ACR has "hard core-soft shell structure", "soft-core-hard shell structure" and "hard-soft-hard three-layer structure", but the current market sales of the main varieties of " Hard shell structure ", with the structure of ACR resin performance is good, more widely used. "Soft-core-hard shell structure" of the core-shell emulsion polymerization, the process is the first step in the emulsion polymerization of the formation of soft latex particles grafted hard monomer. The types and amounts of emulsifiers, the ratio of core-shell, shell monomer feeding, the degree of crosslinking of rubber latex (rubber core), the size of seed and the type and amount of crosslinking agent, and so on. The core-shell structure and ACR's final product performance have a significant impact. We know: plastic processing can not be separated from PVC processing aids, PVC processing aids is a very effective copolymer additives, the main role of this additive is to improve the plastic properties of PVC materials, through the stability of the performance of plastic The normal performance of the product, so that higher quality plastic products, longer life. According to the different needs of materials, PVC processing a lot of types of additives, and today we introduce five more commonly used five types. General type, lubrication type, bright type, super plasticity and super melt strength type.

General purpose: General purpose PVC processing aids is used only to promote the plasticity of the material. Improve the melting of plastic.

Lubrication: In addition to promoting the plastic material, both the role of metal stripping, to prevent the adhesion of the melt and metal surface, extended driving cycle.

Bright type: In addition to promoting the plastic material, can significantly enhance the surface brightness of products, suitable for surface finish need a higher product.

Super plasticity: the ability to promote the plasticization of materials is higher than other types, suitable for difficult to plasticize the material formula, such as high calcium carbonate composition, the amount of lubricant or add carbon black, fiber and other modifier formulations.

Super melt strength type: In addition to promoting the plasticization of materials, but also a substantial increase in the melt strength of materials to improve the stability of production to extend the production cycle and improve the mechanical properties of products, especially suitable for high calcium carbonate content (Greater than wt 30%) of the product.