文献类型：期刊文献

英文题名：Tailoring the Viscoelasticity of HEMA-Functionalized StyreneAcrylate Copolymers Using Coagulants

作者：Xu, Cheng[1];Jiang, Lili[1];Guan, Aiguo[1];Lin, Yu[1];Wu, Guozhang[1]

机构：[1]E China Univ Sci & Technol, Sch Mat Sci & Engn, Shanghai Key Lab Adv Polymer Mat, Shanghai 200237, Peoples R China

年份：2014

卷号：53

期号：49

起止页码：19175

外文期刊名：INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH

收录：;EI(收录号：20145100328143);WOS:【SCI-EXPANDED(收录号:WOS:000346322200061)】；

基金：This work was supported by Grants from the National Natural Science Foundation of China (Grant 51373053), the "973" project (2013CB035505), and the Fundamental Research Funds for the Central Universities.

语种：英文

外文关键词：Crosslinking - Coagulation - Transesterification - Salts - Styrene - Resins

摘要：Coagulation is an important chemical process extensively used to harvest polymeric resins from natural or synthesized suspensions and emulsions. In this work, the coagulants were found effective to tune the viscoelasticity of poly(styrene-co-butyl acrylate) resins containing small amounts of hydroxyethyl methacrylate (HEMA) and methacrylic acid (MAA). Results showed that the viscoelasticity of the copolymers remarkably varied with the type of coagulant. For samples coagulated by H2SO4, the shear modulus G' initially decreased and then rapidly increased with temperature. This observation suggested a cross-linking reaction during rheological measurement. Conversely, G' continuously decreased with increased temperature and exhibited a higher solidlike plateau in the terminal zone for resins coagulated by metal salts with a higher charge/radius ratio. We demonstrated that the cross-linking reaction originated from the transesterification of the hydroxyl group with the ester group both from BA. Cations from the metal salts formed coordination bonds with HEMA hydroxyl during coagulation. These bonds shielded HEMA from transesterification reactions but resulted in physical networking among the copolymer chains.