FTIR and strengthening studies on liquid crystalline oligomers of 2-thioalkoxy/2-alkoxyhydroquinones and terephthaloyl chloride

The properties of liquid crystalline (LC) oligomers produced from 2-thioalk oxyhydroquinones (2-thioalkoxyHQs) and 2-alkonyhydroquinones (2-alkoxyHQs) with terephthaloyl chloride (1a-c, 2a-c) have been studied and their compat ibility with polyamide 11 (PA 11)has been investigated. FTIR studies showed two conformations of the synthesized oligomers. A three-point bending test indicated that oligomeric chains could strengthen the final flexural prope rties of the polyamide. Strength of PA 11 was increased by addition of only 1% of LC oligomers to the matrix, Compatibility bt between oligomer chains and PA 11 was lower than the compatibility between corresponding oligomers of 2-alkoxy-4-hydroxybenzoic acids (2-alkoxyHBAs) and PA Il. (C) 2000 Else vier Science Ltd. All rights reserved.