부산대학교 도서관

Cationic copolymerization of tetrahydrofuran (THF) with e-caprolactone (CL) was carried out with some stable cationic salts. Both monomers are consumed simultaneously, but THF seems twice as reactive as CL, reflecting the high basicity of THF. The copolymerization system seems almost living in nature at higher THF feed and a copolymer of Mn 89000 containing 13.9% of CL was obtained. However, fractionation of the product showed a broad distribution of the copolymer composition. The lower-molecular-weight fraction contained a higher proportion of CL. The X-ray diffraction pattern and differential scanning calorimeter thermogram showed the existence of the crystalline region of poly-THF and poly-CL. Thus the copolymerization may have proceeded by a two-state mechanism yielding a block copolymer.