화학공학소재연구정보센터
Journal of Polymer Science Part A: Polymer Chemistry, Vol.45, No.15, 3391-3399, 2007
Pd (II)-catalyzed vinyl addition polymerization of novel functionalized norbornene bearing dimethyl carboxylate groups
Three novel functionalized polynorbornenes (PNB) with pendant dimethyl carboxylate group (carboxylates-acetate, propionate, and butyrate) are synthesized as a vinyl-type with a palladium (11) catalyst in high yield. The effects of size of substitutents, molar ratio of monomer to catalyst, solvent polarity, reaction time, and temperature on the polymerization of exo-norbornene dimethyl propionate were systematically investigated. The low molar ratio and temperature, as well as high polarity of solvent, and long reaction time, are favorable for the enhancement of the monomer conversion, especially, the solvent have an obvious effect on the catalyst activity. The resulting poly(cis-norbornene-exo-2,3-dimethyl carboxylates) (PNB-dimethyl carboxylates) show good solubility in common organic solvent and high thermal stability up to 360 degrees C. The glass transition temperature was detected by DMA at 331, 324, and 318 degrees C for acetate, propionate, and butyrate, respectively. (C) 2007 Wiley Periodicals, Inc.