Macro-oriented network of liquid-crystalline polyesters: crosslinking induced by gamma-irradiation and thermally activated reaction

The synthesis of a macro-oriented network from liquid-crystalline polymers, bearing pendant groups with unsaturations, is reported. Virgin polymers ar e processable to obtain oriented samples, e.g. fibres, which may be crossli nked through thermal activation and/or exposure to gamma-radiation, The liq uid-crystalline state is "frozen" and the macroscopic anisotropy is preserv ed even at high temperatures. Compared to virgin fibres, irradiated samples show an enhancement of tensile performances, thus indicating that the main effect of irradiation is crosslinking without significant degradation phen omena. (C) 2000 Elsevier Science Ltd. All rights reserved.