The working principle of PVC profile processing aids and common additives

The working principle of PVC profile processing additives and what is pvc profile?
Pvc profile is made of pvc resin by adding a variety of functional additives, after high temperature extrusion out of the molded pvc products for industry and life. It can be divided into two categories according to performance, hard and soft. Hard pvc profiles are mostly used in construction. For example, pvc doors and windows, pvc flooring, pvc pipes and so on. And soft pvc material is used for pvc hose, power transmission cable and so on. After adding functional additives, pvc has more performance. It will have anti-aging, UV resistance, corrosion resistance, high strength, and cheap, so some people are willing to try to use it instead of aluminum profiles, steel and so on.
pvc profile processing aids
1. pvc processing aids principle of action
Due to the pvc melt ductility is very poor, easy to lead to the melt broken, and pvc melt relaxation, easy to lead to the items made of rough surface, no luster and other shortcomings. Therefore, in order to improve its melt defects, in the processing of pvc often have to add processing aids. Processing aids have three main modes of action: to promote the melting of the resin, improve the melt rheological properties, give lubricating properties.
Promote the melting of resin: pvc resin in the heating, melting under the action of certain shear force processing aids first melt and paste in pvc resin particles on the surface, so that the viscosity and friction of pvc increase, effectively transfer the shear force and heat, accelerate the melting of pvc.
Improve the melt rheological properties: processing aids can improve the pvc melt strength poor, poor ductility and melt rupture and other flow properties. The principle is to increase the viscoelasticity of pvc melt, thereby improving the mold release expansion and improve melt strength.
Give lubricity: first let the processing aids and pvc compatible part of the melt, promote the role of the melt, and not with the pvc compatible part of the melt resin system to migrate outside, thus can improve the mold release.
2. pvc common processing aids
ACR processing aids: ACR for methyl methacrylate and acrylate, styrene and other monomer copolymers. It can be used as both processing aids, can also be used as modifiers. ACR processing aids important role is to promote pcv plasticization, shorten its plasticization time, improve the uniformity of melt plasticization and reduce the plasticizing temperature.
Light stabilizing processing aids: pvc profile products are mostly exposed to light and other kinds of light, according to the application environment of the products in the processing of a certain amount of light stabilizing additives can prevent and alleviate the decomposition and aging of the products, prolong the service life of the products.