Views:1 Author:Site Editor Publish Time: 2020-08-25 Origin:Site
PVC is a very special thermoplastic. It is easy to decompose during processing with poor fluidity, low impact strength and poor weather resistance. Therefore, it is necessary to add additives during the processing to improve its performance.
The additives includes lubricants, heat stabilizers, impact modifiers, PVC processing aids, etc. In the development and application of PVC processing aids, the product components are roughly classified into the following categories: methyl methacrylate (MMA) / acrylate copolymer, MMA / styrene copolymer, acrylonitrile / styrene, etc. At present, the mostly used and best effect is MMA/acrylate copolymer.
In PVC foaming formula, in order to obtain a more uniform, small and independent cell structure, some foaming agents such as: AC, NC, foaming regulators are used in the formulation.
PVC foaming regulator is actually an acrylate emulsion polymer, which has all the characteristics of PVC processing aids, but its molecular weight is much higher than PVC processing aids. In PVC foamed product, the purpose of adding the foaming regulator is mainly to increase the melt strength of the melt and prevent the combination of the bubbles to obtain a uniformly foamed PVC foamed product. At the same time, it can also promote the plasticization of PVC and ensure the melt has good fluidity.