Synthesis and characterization of block copolymers: Poly(ethylene oxide-a-methacrylonitrile) and poly(ethylene oxide-6-acrylonitrile)

Abstract

Anionic polymerization of methacrylonitrile was initiated with the disodium salt of poly(ethylene oxide) (PEO) in tetrahydrofuran (THF) at various temperatures in both the presence and the absence of a crown ether or cryptate. In the polymerization at 30°C in the presence of a crown ether, methanol soluble and insoluble block copolymers of PEO and poly-methacrylonitrile were obtained and the composition of the copolymer could be controlled by the feed mole ratio of monomer to initiator. Anionic polymerization of acrylonitrile was also intiated with the disodium salt of PEO in THF at various temperatures. A very small amount of PEO was incorporated into the resulting block copolymer. A branched structure was formed in the polyacrylonitrile (PAN) part of the copolymer through a metalation reaction of PAN. The amount of branched structure decreased with a decrease in the polymerization temperature and was negligible in the copolymer prepared at − 78°C. © 1982 The Society of Polymer Science, Japan.