Accession Number : ADA248700


Title :   Synthesis of Side Chain Liquid Crystal Polymers by Living Ring Opening Metathesis Polymerization. 2. Influence of Molecular Weight, Polydispersity, and Flexible Spacer Length (n=9-12) on the Thermotropic behavior of the Resulting Plymers


Descriptive Note : Technical rept.,


Corporate Author : MASSACHUSETTS INST OF TECH CAMBRIDGE DEPT OF CHEMISTRY


Personal Author(s) : Komiya, Zen ; Pugh, Coleen ; Schrock, Richard R.


Full Text : http://www.dtic.mil/get-tr-doc/pdf?AD=ADA248700


Report Date : 31 MAR 1992


Pagination or Media Count : 27


Abstract : The living ring opening metathesis polymerization of 5-carbo(n-(4'- METHOXY-4BIPHENYLYLoxyalkyl)bicylco2.2.1hept-2-ene (1-n, n=9-12) with Mo(CH-t- Bu)(NAr) (0-t-Bu)2 (Ar=2,6-C6H3-i-Pr2) is described. Polymers with degrees of polymerization from 5 to 100 and narrow molecular weight distributions (Mw/Mn=1. 07-1.28) were obtained in high yield. All polymers exhibit side chain crystallization along with a nematic mesophase. Isotropization temperatures increase with increasing molecular weight and then become independent of molecular weight at approximately 30-50 repeat units. Side chain crystallization is suppressed as molecular weight increases.


Descriptors :   *LIQUID CRYSTALS , *ORGANIC COMPOUNDS , *CHEMICAL REACTIONS , MOLECULAR WEIGHT , CRYSTALLIZATION , OPENINGS , WEIGHT , YIELD , RINGS , POLYMERIZATION , POLYMERS , LIQUIDS , CHAINS


Subject Categories : ORGANIC CHEMISTRY
      POLYMER CHEMISTRY


Distribution Statement : APPROVED FOR PUBLIC RELEASE