Heat stabilizers Overview

Mainly used in PVC and copolymers, polyvinyl chloride in the thermal process, before reaching the melt flow had a small amount of molecular chains and release hydrogen chloride, and hydrogen chloride is a catalyst for accelerating molecular chains chain reaction, so not removed just decomposed hydrogen chloride polymer chain will have a low molecular weight compound cleavage, to cause such PVC plastic molding can, if appropriate in the polyvinyl chloride is added an alkaline substance in the can immediately and the decomposition of hydrogen chloride, to achieve the above purpose, which is heat stabilizer action principle.pigments
Heat stabilizers of the following categories: metal salts and soaps: mainly of lead salts and soaps, such as lead sulfate salt and lead stearate; followed by calcium, cadmium, zinc, barium, aluminum, lithium , strontium salts and soaps. They are the primary stabilizers.
Organic tin: it is transparent PVC products must be the primary stabilizer, and good light stability.PVC impact modifier
Organic stabilizer: Main Ring oxidized oils and esters, it is the secondary stabilizer is a plasticizer.
Chelating agents: Almost all of phosphorous acid esters of alkyl or aryl group, to form complexes with metal salts. Chelating agents alone are not effective, you need to use the main stabilizers in order to show its stability. The main representative chelating agents triphenyl phosphite.