易衍生化温敏高分子刷的制备及其温敏行为研究

温敏材料由于优异的性能和潜在的应用价值而具有良好的发展前景.利用超分子自组装单层(SAM)与表面引发聚合(SIP)技术将2-(2-甲氧乙氧基)甲基丙烯酸乙酯(MEO2MA)与聚乙二醇甲基丙烯酸酯(OEGMA526)的共聚物poly(MEO2MAco-OEGMA526)接枝于金表面,探索了不同引发剂溶液浓度(χIsol)、单体OEGMA526摩尔浓度(C526)与干态膜厚度(d)对该高分子刷性质的影响.应用石英晶体微天平(QCM)对其温敏行为进行研究,结果表明:在χIsol=1%与C526=5%条件下制备的高分子刷,最低临界溶解温度(LCST)为34℃;其LCST由OEGMA526的单体摩尔浓度决定,不受膜厚的影响.该高分子刷在接枝生物素后其与链霉亲和素的结合实验证明,高分子刷末端的羟基为其官能团化提供了契机.该易衍生化温敏高分子刷为发展新型温敏材料提供了研究基础.

Preparation of thermoresponsive and easily functional polymer brushes and their thermoresponsive properties

Thermoresponsive materials have overwhelming development prospects because of their excellent properties and widely potential applications. The polymer brushes of poly（MEO2MA-co-OEGMA526） were prepared by the copolymerization of 2-（2-methoxyethoxy）ethyl methacrylate （MEO2MA） and poly（oligo（ethylene glycol） methacrylate） （OEGMA526） on the gold surface of QCM chip via supramolecular self-assembled monolayers （SAM） and surface initiated polymerization （SIP）. The thermoresponsive properties of polymer brushes were investigated by changing the solution concentration of initiator （χIsol）, the molar concentration of monomer OEGMA526 （C526） and the dry film thickness （d）. Studies via quartz crystal microbalance （QCM） showed that the lower critical solution temperature （LCST） of thermoresponsive polymer brushes poly（MEO2MA-co-OEGMA526） （χIsol = 1%; C526 = 5%; LCST = 34 ℃） was mainly determined by the C526 while the d almost had no effect. Terminal hydroxyl groups on thermoresponsive polymer brushes provided an opening for functional applications verified by the binding experiment of grafted biotin and streptavidin. Thermoresponsive and easily functional polymer brushes provide a new possibility for the development of novel temperature sensitive materials.