Schreck Kathleen M, Leung Diana, Bowman Christopher N
Department of Chemical and Biological Engineering, University of Colorado at Boulder, 424 UCB, 1111 Engineering Drive, Boulder, CO 80309.
Macromolecules. 2011 Sep 15;44(19):7520-7529. doi: 10.1021/ma201695x.
The thiol-ene reaction serves as a more oxygen tolerant alternative to traditional (meth)acrylate chemistry for forming photopolymerized networks with numerous desirable attributes including energy absorption, optical clarity, and reduced shrinkage stress. However, when utilizing commercially available monomers, many thiol-ene networks also exhibit decreases in properties such as glass transition temperature (T(g)) and crosslink density. In this study, hybrid organic/inorganic thiol-ene resins incorporating silsesquioxane (SSQ) species into the photopolymerized networks were investigated as a route to improve these properties. Thiol- and ene-functionalized SSQs (SH-SSQ and allyl-SSQ, respectively) were synthesized via alkoxysilane hydrolysis/condensation chemistry, using a photopolymerizable monomer [either pentaerythriol tetrakis(3-mercaptopropionate) (PETMP) or 1,3,5-triallyl-1,3,5-triazine-2,4,6(1H,3H,5H)-trione (TATATO)] as the reaction solvent. The resulting SSQ-containing solutions (SSQ-PETMP and SSQ-TATATO) were characterized, and their incorporation into photopolymerized networks was evaluated.
硫醇-烯反应是一种比传统(甲基)丙烯酸酯化学更耐氧的方法,用于形成具有多种理想特性的光聚合网络,这些特性包括能量吸收、光学透明度和降低的收缩应力。然而,在使用市售单体时,许多硫醇-烯网络的性能也会下降,如玻璃化转变温度(T(g))和交联密度。在本研究中,研究了将倍半硅氧烷(SSQ)物种引入光聚合网络中的有机/无机杂化硫醇-烯树脂,作为改善这些性能的途径。通过烷氧基硅烷水解/缩合化学合成了硫醇官能化和烯官能化的SSQ(分别为SH-SSQ和烯丙基-SSQ),使用可光聚合单体[季戊四醇四(3-巯基丙酸酯)(PETMP)或1,3,5-三烯丙基-1,3,5-三嗪-2,4,6(1H,3H,5H)-三酮(TATATO)]作为反应溶剂。对所得含SSQ的溶液(SSQ-PETMP和SSQ-TATATO)进行了表征,并评估了它们在光聚合网络中的掺入情况。