D. Tian, P. Dubois, R. Jerome
Apr 7, 1997
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0
Influential Citations
62
Citations
Journal
Macromolecules
Abstract
Homopolymers of 1,4,8-trioxa[4.6]spiro-9-undecanone (TOSUO) and block copolymers of TOSUO and e-caprolactone (e-CL) have been synthesized with aluminum isopropoxide as an initiator in toluene at 25 °C. The homopolymerization is first order with respect to both monomer and initiator, and the end-group analysis agrees with a coordination−insertion mechanism based on the acyl-oxygen cleavage of the TOSUO ring. Living poly(e-caprolactone) (PCL) and poly(1,4,8-trioxa[4.6]spiro-9-undecanone) (PTOSUO) chains are very efficient macroinitiators for the polymerization of TOSUO and e-CL, respectively, with formation of block copolymers of a narrow molecular weight distribution. Size-exclusion chromatography (SEC) and 13C-NMR confirm the blocky structure of the copolymers, in agreement with DSC, which shows two glass transitions characteristic of the amorphous phase of PCL and PTOSUO, respectively. The ethylene ketal pendent groups of the PTOSUO block have been successfully converted to ketones and hydroxyl pendent g...