Vulcanization kinetics of low-protein natural rubber with use of a vulcameter

• Published in: Journal of applied polymer science Vol. 105; no. 6; pp. 3255 - 3259
• Main Authors: Wang, Ping-Yue, Chen, Ying, Qian, Hong-Lian
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 15.09.2007; Wiley
• Subjects: Applied sciences; Exact sciences and technology; kinetics; Natural polymers; Natural rubber; Physicochemistry of polymers; protein; rubber; stage; vulcanization; Vulcanization; Vulcanizate; stage; Reaction order; protein; rubber; Natural rubber; Kinetics; Rate constant; Experimental study; Sulfur; Activation energy
• ISSN: 0021-8995; 1097-4628
• DOI: 10.1002/app.26488

Kinetics of vulcanization of low‐protein natural rubber (LPNR) was studied with the use of a vulcameter. In the induction period of vulcanization, the time t0 of LPNR is longer than that of natural rubber (NR), and the temperature dependences of the time tdis and the rate constant $ k^{1/\alpha}_1 $ of LPNR are greater than that of NR. Both the curing periods of LPNR and NR (except 170°C for LPNR) consist of two stages. The first stage follows first‐order reaction. The rate constant k2 of LPNR in the first stage is substantially the same as that of NR at the same temperature, and so is the activation energy E2. The second stage (end stage of the curing period) does not follow first‐order reaction, and the calculated reaction order n is in the range of 0.67–0.73. Both rate constants of LPNR (except 170°C) and NR at the same temperature are approximately the same, and so is the activation energy E3. The whole process of curing period for LPNR at 170°C follows n = 0.7 order reaction. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007