Properties of Polychloroprene Molecules in Solution

Abstract Polychloroprenes from emulsion and bulk polymerization were investigated in the ultracentrifuge and by means of diffusion experiments. It was found that the sedimentation constants for B-polymers are independent of the polymerization conditions. This is not to the same degree the case for A-polymers. The diffusion coefficients of both types of polymers are more sensitive to differences in size of the molecules formed. A linear relationship between diffusion coefficient and the inverse value of the molecular weight has been established for B-polymers, and an inverse square root dependence for A-polymers. In the terminology of Kuhn and Kuhn, the molecules of the B-polymers should be completely drained and the molecules of the A-polymers incompletely drained. The shape of the molecules and the polydispersity of the substances are discussed. The difficulties of obtaining true and accurate values of molecular constants for such an inhomogeneous material are pointed out. This investigation is a part of...