A TRIPLE-BONDS-CONTAINING POLY(ETHER/ESTER) - SYNTHESIS, CHARACTERIZATION AND CROSS-POLYMERIZATION

A segmented poly(ether/ester) multiblock copolymer containing acetylene groups within the hard segment was synthesized starting from poly(ethylene glycol) with a number-average molecular weight ($) over bar M(n) = 1000, 2-butyne-1,4-diol and terephthaloyl dichloride. Thermal and spectroscopic data suggest a blocky structure of the copolymer prepared. Nuclear magnetic resonance spectroscopy shows an average degree of polymerization of the hard segments of about 6. By heating in the presence or absence of a catalyst, the monoacetylene units in the hard segments are cross-polymerized below and above their melting temperature. The cross-polymerized material reveals a maximum gel fraction of 93,5 wt.-%, does not crystallize and shows reversible deformability in contrast to the starting polymer. In accordance with previous reports it is concluded that cross-polymerization is possible only in a polymer distinguished by some degree of chain ordering.