Accession Number:

ADA272711

Title:

Ring-Opening Metathesis Polymerization of (+) and (+ or -)-endo,exo-5,6- Dimethylbicyclo(2.2.1)hept-2-ene by Mo(CH-t-Bu)(N-2,6-C6H3-i-Pr2)(OR)2

Descriptive Note:

Technical rept. no. 21,

Corporate Author:

MASSACHUSETTS INST OF TECH CAMBRIDGE DEPT OF CHEMISTRY

Report Date:

1993-10-20

Pagination or Media Count:

31.0

Abstract:

Ring-opened polymers of - and --endo,exo-5,6-dimethylbicyclo2.2. 1hept-2-ene 1 having cis double bond contents between 5 and 85 were prepared using MoCH-t-BuNArOR2 Ar 2,6-C6H3-i-Pr2 OR OCMe3, OCMe2CF3, OCMeCF32 complexes as initiators. The cis content of the polymers increased in proportion to the electron-withdrawing power of the alkoxide ligands. 13C NMR spectra 125 MHz of these polymers were interpreted in terms of the various possible types of dyad structure XX, XN NX, NN, where X and N refer to substituents derived from exo and endo methyl groups, m and r refer to the meso isotactic or racemic syndiotactic configuration of adjacent cyclopentane rings in the chain, and tt, tc, ct, and cc refer to the cistrans double bond sequences. High cis polymer made from 98 -l contained 78 m dyads and had more than twice the optical rotatory power and a higher Tg 85 deg C compared to a high trans polymer 48 m dyads Tg 55 deg C.

Subject Categories:

  • Organic Chemistry
  • Physical Chemistry
  • Polymer Chemistry
  • Optics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE