Divinyl ethers 1, 2, 3 and 4 caused ring-expansion cationic cyclopolymerization with a hemiacetal ester-incorporated cyclic initiator in conjunction with SnBr4 to yield cyclic Poly(1), Poly(2), Poly(3) and Poly(4), respectively. High degree of cyclization of cyclopolymerization (>~98%) was necessary to obtain these macrocyclic cyclopolymers of well-defined structure quantitatively. The Tgs of these macrocyclic cyclopoly(divinyl ether)s were higher than those of the corresponding linear cyclopoly(divinyl ether)s.
- Takeshi Namikoshi
- Takafumi Yamamoto
- Toshikazu Sakaguchi
