POLYMERS CONTAINING SUBSTITUTED 2-PHENYL-BENZOXAZOLE SIDE-CHAIN GROUPS - SYNTHESIS AND PHASE-BEHAVIOR

The synthesis of substituted 2-phenyl-benzoxazoles has been accomplish ed by ring closure of Schiff bases. The compounds have been used as pr ecursors of acrylic derivatives displaying LC properties: GRAPHICS R(1 ) = NO2, CN; R(2) = -OOC-pC(6)H(4)-O(CH2)(6)OOCCH = CH2; R(1) = -OOC-p C(6)H(4)-O(CH2)(6)OOCCH = CH2, -N(CH3)(CH2)(6)OOCCH = CH2; R(2) = NO2 Four comb-like homopolymers have been obtained by radical catalysis fr om the acrylic monomers. The polymers have been characterized by H-1-N MR, DSC, x-ray diffraction, viscometry, and polarizing microscopy. Thr ee of the polymers exhibit liquid crystalline properties of smectic ty pe. (C) 1996 John Wiley & Sons, Inc.