Accession Number : ADA183435
Title : Liquid Crystalline Polymers Containing Heterocycloalkane Mesogenic Groups. 5. Synthesis of Biphasic Chiral-Smectic Polysiloxanes Containing 2,5-Disubstituted-1,3-Dioxane and 2,5-Disubstituted-1,3,2-Dioxaborinane Based Mesogenic Groups.
Descriptive Note : Technical rept.,
Corporate Author : CASE WESTERN RESERVE UNIV CLEVELAND OH DEPT OF MACROMOLECULAR SCIENCE
Personal Author(s) : Hahn,Bruce ; Percec,Virgil
Report Date : 1987
Pagination or Media Count : 40
Abstract : The synthesis of side-chain liquid crystalline polysiloxanes containing chiral mesogenic side-groups, is presented. Differential scanning calorimetry and optical polarization microscopy revealed chiral smectic mesomorphism for all polymers. The last two polymers present also a chiral smectic-C mesophase. All copolymers exhibit two glass transition temperatures; one due to the independent motion of the main chain, the other due to the cooperative but independent motion of the side-groups. Therefore, these liquid crystalline copolymers are biphasic systems resembling the behavior of phase separated graft copolymers, i.e., they exhibit a micro-phase separated morphology containing main-chain and side-chain domains.
Descriptors : *COPOLYMERS, *SILOXANES, *POLYMERS, *ALKANES, CALORIMETRY, CHAINS, DOMAIN WALLS, GLASS, GRAFT POLYMERIZATION, LIQUID CRYSTALS, MICROSCOPY, MOTION, OPTICAL ANALYSIS, POLARIZATION, SCANNING, SEPARATION, TRANSITION TEMPERATURE, SYNTHESIS(CHEMISTRY)
Subject Categories : Polymer Chemistry
Distribution Statement : APPROVED FOR PUBLIC RELEASE