2014-01-02 by seoer8Pure PVC resin is very sensitive to heat , when the heating temperature reaches 90Y: or more, will be a minor thermal decomposition reaction , the temperature was raised to 120C while increasing the decomposition reaction, 150C, PVC resin, the original white gradually turns yellow - red - brown - black. PVC resin decomposition reaction is due to the de- HCL caused a chain reaction , leading to macromolecules strand breaks. PVC heat stabilizers to prevent thermal decomposition mechanism is through the following aspects to achieve. ( 1 ) by capturing the thermal decomposition of PVC HCl, to prevent catalytic degradation of HCl . The main mechanism of action of lead salts class here , in addition to metal soaps , organic tin , phosphorous and other lipids and epoxy . ( 2 ) replacement of the reactive allylic chlorine atom. Metallic soaps , lipids and organic phosphorous tin can here the role of the mechanism . ( 3 ) reaction with free radicals , the radical termination reaction . Organic tin and phosphorous lipid mechanism role here .