標題: Kinetics and curing mechanism of epoxy and boron trifluoride monoethyl amine complex system
作者: Li, YS
Li, MS
Chang, FC
應用化學系
Department of Applied Chemistry
關鍵字: epoxy;cationic polymerization;kinetics;reaction mechanism
公開日期: 15-九月-1999
摘要: The kinetics of cationic polymerization of epoxy resin has been studied. Due to multiple reaction exotherms and irregular baselines involved in this system, the ASTM E 698 method was chosen to determine the kinetic parameters of this epoxy/BF3-MEA system. The DER 332/BF3-MEA system follows the first order active chain end (ACE) reaction mechanism. The adding of the hydroxyl group into the system is prone to decrease the activation energy and shifts the curing into the activated monomer (AM) mechanism due to the stronger nucleophilicity of the hydroxyl group than the epoxide group. On the other hand, the DER 331/BF3-MEA system possesses lower activation energy because the DER 331 contains more hydroxyl groups-alpha-glycol and secondary alcohol. The former is the major contributor in lowering the activation energy. The hydroxyl group also can act as a chain transfer agent by retarding the propagation process, thus the reaction rate of the DER 332/BF3-MEA system is higher than the DER 331/BF3-MEA system. The DER 332/BF3-MEA system shows good correlation between the experimental data (FT-IR, DSC, and GPC) and the simulation curve based on ASTM E 698 before gelation, while a larger deviation is observed in the DER 331/BF3-MEA system. After gelation, the hydroxyl group also acts as an active site to react with residual epoxy monomers and obtain a more condense matrix. (C) 1999 John Wiley & Sons, Inc.
URI: http://hdl.handle.net/11536/31088
http://dx.doi.org/10.1002/(SICI)1099-0518(19990915)37:18<3614
ISSN: 0887-624X
DOI: 10.1002/(SICI)1099-0518(19990915)37:18<3614
期刊: JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY
Volume: 37
Issue: 18
起始頁: 3614
結束頁: 3624
顯示於類別:期刊論文


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  1. 000082336400009.pdf