文献类型：期刊文献

英文题名：Preparation and properties of benzoxazine precursors containing siloxane units and their epoxy copolymers

作者：Liu, Lele[1];Wang, Fan[1];Zhu, Yaping[1];Qi, Huimin[1]

机构：[1]East China Univ Sci & Technol, Sch Mat Sci & Engn, Key Lab Specially Funct Polymer Mat & Related Tec, Minist Educ, 130 Meilong Rd, Shanghai 200237, Peoples R China

年份：2023

卷号：35

期号：3

起止页码：251

外文期刊名：HIGH PERFORMANCE POLYMERS

收录：;EI(收录号：20224012840964);WOS:【SCI-EXPANDED(收录号:WOS:000855508300001)】；

基金：The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work is supported by the Fundamental Research Funds for the Central Universities (50321041918013, 50321041917001).

语种：英文

外文关键词：Benzoxazine; siloxane; epoxy resin; copolymer; sulphone group

摘要：Four siloxane benzoxazines containing different rigid segments were successfully synthesized and characterized herein, including a benzene ring, a biphenyl, a naphthalene ring, and a diphenyl sulfone group. Different rigid segments had different effects on polymer properties. The introduction of the naphthalene ring and sulfone group considerably reduced the curing temperature of benzoxazine. Although the benzoxazine with the naphthalene ring exhibited low heat resistance, all the four samples showed a high char yield at 800 degrees C under nitrogen atmosphere. In addition, during copolymerization with AG-80 epoxy, the introduction of epoxy promoted the curing of the benzoxazines containing the naphthalene ring and sulfone group. The heat resistance of all copolymers was considerably improved, especially for the copolymer containing the naphthalene ring, whose 5% thermal weight loss temperature (T-d5) increased from 248 degrees C to 321 degrees C under nitrogen atmosphere. The copolymer containing the biphenyl structure had the highest glass transition temperature, reaching 259.1 degrees C. Copolymerization with epoxy also considerably improved the tensile strength and elongation at break of the copolymers, which were much higher than those of traditional bisphenol A-aniline based benzoxazine (BA-a). Compared with the neat benzoxazine prepared using siloxane and bisphenol A, the developed copolymers also had better tensile properties, and the copolymer containing the sulfone group showed the greatest improvement (from 49 to 69 MPa, from 3.1% to 9.12%).