Structure-Property Relationships for Neoprene Type W

Elastomers

“…In Neoprene Type W, organic acids showr effects that bear no relation to their dissociation constants. Fractional precipitation of Neoprene Type W shows that its molecular vreight distribution approaches that of natural rubber and is more nearly uniform than that of other types of neoprenes or GR-S (105). Products of ozonolysis gave no evidence of lateral double bonds.…”

cis-Polychloroprene

“…The k' values reported for trans-polychloroprene are mostly in the range 0.35-0.40. 13 Some physical properties of cis-polychloroprene and 95% trans-polychloroprene are compared in Table I.…”

Relationship between Molecular Structure and Physical Properties

“…There is also evidence that lower polymerization temperatures tend to discourage chain branching and cross linking (38). Viscosity studies on a series of polybutadienes prepared at different reaction temperatures also led to the conclusion that lower polymerization temperatures gave molecules with less branching (39). This was deduced from the systematic trend of the exponent of the molecular weight in the equation connecting the intrinsic viscosity with the molecular weight.…”