writer：Binyuan Liu*, Yang Li, IL Kim*, Boo-gyo Shin, Do Yeung Yoon, Li Zhang, Rongqin Ji, Weidong Yan
keywords：Thermal characterization, Thermal degradation, PNB-dialkyl esters
source：期刊
specific source：Polym Degrad Stabl, 2007, 92, 868-875.
Issue time：2007年

The thermal properties and degradation behaviors of poly(norbornene-2,3-dicarboxylic acid dialkyl esters) (PNB-dialkyl esters)  were investigated by thermogravimetric analysis (TGA) in dynamic conditions and by infrared (IR) spectroscopy. The PNB-dialkyl esters show good thermal stability up to 350 C, and the thermal stability decreases in the order Me > Et > Pr > Bu with the increase in size of side chain. The effect of side-chain size on the thermal degradation behaviors of PNB-dialkyl esters is evidenced by one-step thermal degradation profile for PNB-Me while two-step thermal degradation profile for PNB-Et, PNB-Pr, and PNB-Bu. Transformation is deduced to undergo b-hydrogen elimination and formation of anhydride group in the first stage of thermal degradation reaction according to TGA and IR results for PNB-Et, PNB-Pr, and PNB-Bu. The apparent activation energy and thermal degradation model of PNB-dialkyl esters are estimated by means of OzawaeFlynnewall method and PhadniseDeshpande method, respectively.