Molecular Engineering of Liquid Crystalline Polymers by Living Polymerization. 5. Synthesis and Mesomorphic Behavior of Poly(2-(4-Cyano-4'- Biphenyl)oxy)ethyl Vinyl Ether-co-8-(4-Co-4'-Biphenyl)oxy)octyl Vinyl Ether)
CASE WESTERN RESERVE UNIV CLEVELAND OH DEPT OF MACROMOLECULAR SCIENCE
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The synthesis and characterization of poly 2-4-cyano-4 -biphenyl oxy ethyl vinyl ether poly6-2, poly 8-4-cyano-4biphenyloxyocctyl vinyl ether poly6-8 and poly 6-2-co6-8 XY where XY is the molar ratio of the two monomeric structural units with degrees of polymerization of about 10 and narrow molecular weight distribution are described. Both homopolymers and copolymers were prepared by living cationic polymerization and copolymerization of 6-2 and 6-8. During the first heating scan poly6-2 presents an inverse monotropic s sub c mesophase. During subsequent heating and cooling scans, this polymer is amorphous regardless of the thermal history of the sample. Poly6-8 exhibits an enantiotropic s sub a mesophase. Both during the first and subsequent haeting and cooling scans, the phase diagram which plots the dependence of mesomorphic transition temperatures as a function of copolymer composition presents a discontinuity.
- Organic Chemistry