Synthesis and Characterization of Liquid Crystalline Copolymethacrylates, Copolyacrylates and Copolysiloxanes Containing 4-Methoxy-4'-Hydroxy-alpha-Methylstilbene and 4-Hydroxy-4'-Methoxy-alpha-Methylstilbene Constitutional Isomers as Side Groups.
Abstract
The synthesis of methacrylates and acrylates containing 4-methoxy-4'-hydroxy-alpha methylstilbene and 4-hydroxy-4'-methoxy-alpha-methylstilbene constitutional isomers attached to the polymerizable group through flexible spacers containing eleven, eight, six, three and respectively two methlenic units is described. The radical copolymerization of a 1/2 or 2/1 mole ratio of the two constitutional isomeric monomers led to thermotropic side-chain liquid crystalline polymers in all cases. The synthesis of copolysiloxanes based on the same constitutional isomeric mesogens as side groups, and flexible spacers containing eleven, eight, six, five and respectively three methylenic units is also described. All polymers were characterized by differential scanning calorimetry and optical polarization microscopy. The polymers containing eleven methylenic units in the spacer exhibit SC mesomorphism, while the other polymers are nematic. Copolymetharcrylates do not undergo side-chain crystallization. Only the copolyacrylate containing eleven methylenic units in the spacer exhibits side chain crystallization. All the copolysiloxanes present side-chain crystallization. The number of melting transitions presented by these polymers decreases with the decrease of their spacer length.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1987
- Accession Number
- ADA183705
Entities
People
- Chain S. Hsu
- Dimitris Tomazos
- Virgil Percec
Organizations
- Case Western Reserve University