Synthesis and Characterization of Amorphous-Liquid Crystalline Poly(Vinyl Ether) Block Copolymers

A new series of amorphous-liquid crystalline poly(vinyl ether) block copolymers was synthesized using living cationic polymerization and free-radical polymerization techniques. Vinyl ether monomer was polymerized using a trifluoromethane sulfonic acid and methyl triflouoromethanesulfonate/tetrahydrothiophene initiator system in dichloromethane at -18oC, and quantitatively terminated with labile azo compounds in order to obtain poly(vinyl ether) with well-defined molecular weight and end groups. This polymer was used in a subsequent blocking step in which azo groups were decomposed at 80oC in the presence of methyl methacrylate and styrene monomer. In both copolymers, blocks of different chemical composition were segregated in the solid and melt-phase transitions. The mesophase-transition temperatures of the liquid-crystalline blocks were found to be very similar to those of the corresponding homopolymers.

Synthesis and Characterization of Amorphous-Liquid Crystalline Poly(Vinyl Ether) Block Copolymers

A new series of amorphous-liquid crystalline poly(vinyl ether) block copolymers was synthesized using living cationic polymerization and free-radical polymerization techniques. Vinyl ether monomer was polymerized using a trifluoromethane sulfonic acid and methyl triflouoromethanesulfonate/tetrahydrothiophene initiator system in dichloromethane at -18oC, and quantitatively terminated with labile azo compounds in order to obtain poly(vinyl ether) with well-defined molecular weight and end groups. This polymer was used in a subsequent blocking step in which azo groups were decomposed at 80oC in the presence of methyl methacrylate and styrene monomer. In both copolymers, blocks of different chemical composition were segregated in the solid and melt-phase transitions. The mesophase-transition temperatures of the liquid-crystalline blocks were found to be very similar to those of the corresponding homopolymers.
Turkish Journal of Chemistry-Cover
  • ISSN: 1300-0527
  • Yayın Aralığı: Yılda 6 Sayı
  • Yayıncı: TÜBİTAK