Abstract: | In this article we will discuss the synthesis of the new copolymers of norbornene derivatives with an ester group and carbon monoxide, using Pd(CH3CN)4(BF4)2 as a catalyst and 2,2′-bipyridine as a ligand in nitromethane/methanol at 60°C. Elementary analysis, infrared spectra, and NMR spectra indicated that copolymers contain ketone, ester, and bicyclic structures. Methanol functions as the coinitiator and chain transfer agent in copolymerization. A decrease in the molar ratio of CH3OH]/Pd] caused an increase in molecular weight and a decrease in yield of the copolymer. The number-average molecular weight of copolymers (M n) ranged from 3800 to 5300, and the glass transition temperature (Tg) ranged from −32 to 117°C. Thermal analysis revealed that both T and T exceeded 180 and 230°C, respectively. Linear long-chain substituents such as n-C11H23C(O) O CH2 drastically reduced Tg to a value of −32°C. In general, copolymers having a longer linear side-chain substituents of ester on norbornene have a more desirable solubility. Moreover, X-ray diffraction demonstrated that the degree of crystallinity decreases with an increasing length of side chain substituents. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1785–1790, 1998 |