Molecular Engineering of Liquid Crystalline Polymers by Living Polymerization. 22. Synthesis and Characterization of Binary Copolymers
Abstract
The synthesis and characterization of poly(11-(4-cyano-4'-biphenyl) oxy)undecanyl vinyl ether-co-(2S,3S)-(+)-2-chloro-3-methylpentyl 4'-(8- vinyloxyoctyloxy)biphenyl-4-carboxylate)X/Y (poly(6-11)-co-(15-8)X/Y) (where X/Y represents the molar ratio of the two structural units) and poly(2S,3S)-(+)-2- chloro-3-methylpentyl 4'-(8-vinyloxyoctyloxy)biphenyl-4-carboxylate-co-3((4- cyano-4'-biphenyl)oxy)propyl vinyl ether)X/Y (poly(15-8)-co-(6-3))X/Y) with degree of polymerization of about 20 and molecular weight distribution of about 1.1 are described. The mesomorphic behavior of all copolymers determined from both first, second and subsequent differential scanning calorimetric (DSC) scans was discussed as a function of composition. As determined from the second DSC scans, poly(6-11) exhibits enantiotropic smectic A and sX (unidentified smectic) , poly(6-3) enantiotropic nematic mesophases, while poly(15-8) exhibits enantiotropic sA, chiral smectic C and sX (unidentified smectic) mesophases. Poly(6-11)-co-(15-8)X/Y exhibit a sA phase over the entire range of compositions. This mesophase displays a continuous dependence of copolymer composition with an upward curvature. Poly(15-8)-co-(6-3)X/Y from 10/0 to 3/7 displays an enantiotropic sA mesophase as their highest phase, while those with X/Y from 2/8 to 1/9 an enantiotropic cholesteric mesophase.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 27, 1992
- Accession Number
- ADA248287
Entities
People
- Myongsoo Lee
- Qiang Zheng
- Virgil Percec
Organizations
- Case Western Reserve University