Blends of the homo- and copolymers of ethylene and vinyl chloride: A compatibility study.

Ethylene-vinyl chloride (E-V) copolymers, obtained through the reductive dechlorination of poly(vinyl chloride) (PVC), were blended from solution with each other and with their constituent homopolymers. Differential scanning calorimetry (DSC) measurements were performed on these copolymer-copolymer and copolymer-homopolymer blends to determine their compatibility. In general the E- V copolymer blends with polyethylene were incompatible, while those with PVC were compatible only for E-V copolymers with high V contents (>80 mol%). Blends of the amorphous E-V copolymers were found compatible if their V contents differed by less than 15 mol%, while blends where one or both E-V copolymers are crystalline were found to be incompatible. The thermal behaviors of these blends, are observed by DSC, are discussed in terms of the microstructures and thermal properties of the constituent E-V copolymers.