Thermosets obtained by chemical modification of poly(epichlorohydrin) with vinyl-terminated aromatic carboxylates

Poly(epichlorohydrin) was modified in a high extent with several vinyl-terminated aromatic potassium carboxylates (4-(2-propenyloxy)benzoate, 4-(5-hexenyloxy)benzoate, 3-(2-propenyloxy)-2-naphthoate, 3-(5-hexenyloxy)-2-naphthoate and 2-(thioallyl)nicotinate) under solid-liquid phase-transfer conditions. Simultaneously with this substitution reaction, cleavage and crosslinking side reactions occurred. The polymers obtained were characterized by NMR, IR, elemental analysis, viscosimetry, size exclusion chromatography (SEC), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Then, crosslinked materials were obtained by curing mixtures of these linear polymers with 10% w/w of a radical initiator (dicumyl peroxide or 2,2'-azoisobutyronitrile) on a DSC device. Finally, the thermal stability of the thermosetting materials was tested by TGA, and the Arrhenius kinetic parameters were determined for dicumyl peroxide initiated crosslinking processes by calorimetric measurements.