PVC stabilizer heat discoloration Comment

Ideal PVC structure is the first - the tail structure-CH2-CHCl-CH2-CHCl-, is quite stable. But so far the synthesis method can not be like PVC synthetic butadiene rubber as a catalyst in the role  WSD PVC flame retardant of Jigger be oriented so that there are rules cis-butadiene polymerization. All kinds of heat stabilizer heat discoloration Comment
 Thermal stabilizers should preferably absorb both HCL, to eliminate the active site, the addition of a conjugated polyene chain, carbenium salt damage, etc. to prevent auto-oxidation, which does not produce the product of the catalytic degradation of PVC. The actual heat stabilizers have different functions due to exhibit different thermal stability characteristics, can WSD Titanium dioxide rutile  be divided into early-type, long-term, intermediate-and versatile four. A) cadmium, zinc soap is typical of early-type heat stabilizers, can quickly absorb HCL, and effectively substituted with carboxylate PVC unstable chlorine atom in the catalytic chain Cd, Zn, thereby effectively suppressing early degradation and coloring , but because of the consumption of fast and transformation products CdC12, ZnC12, but also off the HCL efficient catalyst PVC, PVC and thus lead to the degradation of the material suddenly vicious black, so poor long-term thermal stability. 2) barium, calcium soaps are typically long-term thermal stabilizers, absorption HCL function only and therefore can not inhibit coloring PVC, but the conversion WSD one pack stabilizer  product BaC12, CaC12 do not have catalytic activity, does not cause a sudden black PVC, long-term heat stability better. 3) fatty acids, organic tin are intermediate, both absorption HCL, can effectively replace with carboxylate unstable chlorine atoms PVC chain, and transformation products do not have catalytic activity. 4) mercaptan organotin it has versatile features, while a variety of mechanisms can stabilize PVC, transformation products do not have catalytic activity, and therefore both excellent initial and long-term thermal stability effect.