Structural studies of optically active and racemic isotactic polymers

✍ Scribed by Tadokoro, Hiroyuki

• Publisher: Wiley (John Wiley & Sons)
• Year: 1981
• Weight: 481 KB
• Volume: 4
• Category: Article
• ISSN: 0025-116X
• DOI: 10.1002/macp.1981.020041981110

✦ Synopsis

The structure and optical compensation of polymers having asymnetric carbon atoms in the main chain are discussed. When rectus (R) and sinister ( S ) isotactic ( it) polymers mix in a 1:1 ratio giving a racemic crystalline sample, three kinds of optical compensation can be considered; (a) optical compensation in a unit cell, (b) compensation in a crystallite, and (c) intercrystallite compensation. it-Poly( tert-butylethylene oxide) forin I, itpoly(tert-butylethylene sulfide), and it-poly( isopropylethylene sulfide) are of case (a). it-Poly(isopropy1ethylene oxide), it-poly(propy1ene sulfide), it-poly-6hydroxybutyrate, i t-poly(6-ethyl-6-propiolactone) , and it-poly( tert-butylethylene oxide) form I1 correspond to case (c). The results of the x-ray analyses of these polymers clearly show a stereoselective mechanism o f polymerization in the cases o f catalytic systems used.