AbstractVinyl chloride (VCM) was polymerized by free‐radical suspension procedures in presence of methyl‐substituted olefins such as propylene, isobutylene,cis‐2‐butene, trimethylethylene, and tetramethylethylene. Dilute solution viscosities of polymer formed in the presence of these olefins were measured and compared to that of trichloroethylene, a chlorinated chain‐transfer agent. A pseudo‐chain‐transfer coefficient for these olefins was calculated based on solution viscosity determinations and found to be exponentially proportional to the number of allylic hydrogens. The effects on melt flow of the olefin distribution in the polymer chain were examined. Olefins at the ends of polymer chains were found to have no effect on melt rheology, whereas those in internal portions of chains were found to significantly incre
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