EFFECTS OF BRANCHING ON MELT-PREPARED POLY(PHENYLENE SULFIDE)

Poly(phenylene sulfide), made via the melt polymerization of p-diiodobenzene and sulfur, has been prepared with added branching species at levels up to 1.0 mol%. Effects of increasing branching on the thermal characteristics were seen to be quite large for even 0.25 mol% brancher. Both the T(m) and the apparent rate of crystallization, as judged by the undercooling for melt crystallization, T(m) minus the crystallization upon cooling from the melt, decreased rapidly with increasing brancher level. Melt rheology also confirmed the large increase in melt elasticity in this system with increasing branching level, even at the moderate melt viscosities of the polymers of this work. Melt elasticity for polymers with 0.5 mol% brancher or above was sufficiently high to preclude rheological testing.