Donald Norman Schulz

Synthesis and properties of poly(vinyl chloride-g-2-methyl-2-oxazoline)

SummaryPoly(vinyl chloride-g-2-methyl-2-oxazoline) copolymers were prepared by grafting from the allyl chloride sites of PVC with KI or AgOSO3CF3 as coinitiators. Use of AgOSO3CF3 led to higher grafting efficiencies and higher contents of poly(2-methyl-2-oxazoline) in the graft copolymers. DTA analyses of the P(VC-g-Me-Oxz) identified the thermal transitions of this copolymer; TGA analyses showed that the graft copolymers were less thermally stable than the constituent homopolymers. Unlike blends of P(Me-Oxz) and PVC, the graft copolymers could be molded easily; the graft materials exhibited greater flexural moduli but lower HDTs than PVC.

Evidence of strain-induced phase separation in isopropyl azodicarboxylate modified polybutadiene

SummaryPolybutadiene (BR) has been modified by reaction with isopropyl azodicarboxylate (IAD). The reaction is quite efficient -- resulting in a structure in which there are pendant hydrazoester groups dangling from the BR backbone. The cohesive strength and autohesion of BR are increased by the IAD modification. It is proposed that this polymer is capable of strain-induced phase separation -- a mechanism of self-reinforcement. Evidence for this is the appearance of a new strain-induced thermal transition in the DSC scan of this material.