Three factors affect PVC PVC heat stabilizers transparency

 PVC heat stabilizers to some extent will affect the transparency of PVC. PVC heat stabilizers are also not missing PVC additives, no PVC PVC heat stabilizers so will lose a lot of practical value. So people are constantly biochemical studies of PVC heat stabilizers. The following three factors will affect the transparency of PVC PVC heat stabilizers, and we do a discussion.
1, the refractive index of the stabilizer
PVC resin, heat stabilizer and 1.52 to 1.55 and a refractive index of visible light or near the same, the better the transparency of PVC products, the transparency is low and vice versa.
2, stabilizer molecules (molecules) of linear length
Heat stabilizer molecule (or molecules) linear length of less than 400 ~ 735nm wavelength of visible light refraction less transparency higher, whereas less transparent.
3, a heat stabilizer in PVC, "solubility", i.e., the compatibility of
Compatibility is two or more  Chrolinated polyethylene substances refers to the affinity of each when mixed. Compatibility is good that it is possible to achieve molecular level dispersion. A thermal stabilizer in the molten state has good compatibility with PVC resin. Do not form a two-phase, which is not obvious interface or interface, refraction less, more transparent PVC products. Liquid stabilizer than the corresponding solid metal soaps in PVC compatibility, the length of the linear molecule and smaller, and thus the higher the transparency of the PVC. Free radical polymerization of vinyl chloride is polymerized random, in addition to its first stable - tail structure, and the first - the first structure - CH2-CHCl-CHCl-CH-, tail - tail structure-CHCl-CH2-CH2-CHCl -; vinyl Results generated with coupling disproportionation CH2 = CH-CHCl-CH2-, and allyl chloride structure-CH2-CH = CH-CHCl-CH2 and the like.
Generating allyl chloride, chlorine and PVC flame retardant  tertiary carbon double bond in the synthesis of PVC is its molecular chain structure is unstable factors of instability order: PVC internal molecular chain allyl chloride> tertiary carbon chloro> allyl end groups chloride> Chung chlorine. It is easily degraded because of instability in the structure of PVC molecular chains exist, if not for stabilization when modified PVC processing, the decomposition temperature is about 130 ℃, but that the PVC resin processing into useful products, molding  Acrylic impact modifier temperature to at 190 ℃ or more. Thus, heat stabilizers must be added to improve its structure is stabilized.
So pvc needs to be added during the synthesis PVC heat stabilizers.