Thermal characterization and thermal degradation of poly(norbornene-2,3-dicarboxylic acid dialkyl esters) synthesized by vinyl addition polymerization

• Published in: Polymer degradation and stability Vol. 92; no. 5; pp. 868 - 875
• Main Authors: Liu, Binyuan, Li, Yang, Kim, I.L., Shin, Boo-gyo, Yoon, Do Yeung, Zhang, Li, Ji, Rongqin, Yan, Weidong
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.05.2007; Elsevier Science
• Subjects: Applied sciences; Chemical reactions and properties; Degradation; Exact sciences and technology; Organic polymers; Physicochemistry of polymers; PNB-dialkyl esters; Thermal characterization; Thermal degradation; Vinyl addition polymerization; Thermal characterization; PNB-dialkyl esters; Vinyl addition polymerization; Thermal degradation; Experimental study; Functional polymer; Thermal stability; Saturated polymer; Thermal properties; Reaction mechanism; Property structure relationship; Kinetics; Norbornene derivative polymer; Activation energy
• ISSN: 0141-3910; 1873-2321
• DOI: 10.1016/j.polymdegradstab.2007.01.029

The thermal properties and degradation behaviors of poly(norbornene-2,3-dicarboxylic acid dialkyl esters) (PNB-dialkyl esters) (alkyl = Me (PNB-Me), Et (PNB-Et), Pr (PNB-Pr), and Bu (PNB-Bu)) 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 β-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 Ozawa–Flynn–wall method and Phadnis–Deshpande method, respectively.