THERMALLY REACTIVE OLIGOMERS OF AROMATIC POLY(ETHER SULFONE) CONTAINING POLY(DIMETHYLSILOXANE) .1. SYNTHESIS AND CHARACTERIZATION

Thermally crosslinkable oligomers of aromatic poly(ether sulfone) (PSU) with incorporated poly(dimethylsiloxane) (PDMS) segments were produced via Pt-catalyzed hydrosilylation of alpha , omega -di(silane)PDMS with h alpha , omega -di(vinylbenzyl)PSU. A 2/1 molar ratio of PSU to PDMS was used to obtain statistically a 'triblock' copolymer with on average one PDMS segment incorporated between two PSU segments. Nuclear magnetic resonance analysis of prepared 'triblocks' revealed that the reaction could be performed without detectable side reactions of the hydrosilane end groups of the PDMS. Thermal characterization of the 'triblocks' showed the thermal transitions of both segments, both before and after curing, to be highly dependent on the molecular weight of the component segments, good phase separation being realized at relatively low molecular weights, approx. 3000 for both segments. Dynamic-mechanical/ rheological studies were also performed on these 'triblocks'.