State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China; University of Chinese Academy of Sciences, Beijing 100049, China.
State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China.
Colloids Surf B Biointerfaces. 2013 Nov 1;111:333-41. doi: 10.1016/j.colsurfb.2013.06.029. Epub 2013 Jun 21.
Surface-initiated atom transfer radical polymerization (SI-ATRP) is a versatile tool for surface functionalization in a well-controlled manner. However, surface modification of styrenic thermoplastic elastomers (STPEs) faces a great challenge because immobilization of typical ATRP initiators onto STPEs needs to be carried out in organic solvent, which dissolves and destroys the STPEs film. In this work, a simple aqueous-based route is developed to immobilize ATRP initiators, Br, onto the surface of styrene-b-(ethylene-co-butylene)-b-styrene elastomer (SEBS), chosen as a model copolymer of STPEs. In such a way, functional polymer brushes of ethylene glycol methyl ether methacrylate (OEGMA) are successfully prepared from the surface of SEBS. Kinetic investigations show an approximately linear relationship between grafting density and reaction time, indicating the growth of chains is coincident with a "controlled" process. CBr bonds directly connected to benzene rings on the SEBS-Br surfaces are demonstrated to be effective initiation sites for SI-ATRP. The even coverage of the surface by well-defined P(OEGMA) brushes enable SEBS films to exhibit excellent resistance to protein adsorption and platelet adhesion as well as low hemolysis ratio. This work not only manipulates the SEBS surface to substantially improve its biocompatibility, but paves a way to facilitate SI-ATRP on the surface of styrene-based block copolymers (SBCs).
表面引发原子转移自由基聚合（SI-ATRP）是一种用于以可控方式进行表面功能化的多功能工具。然而，苯乙烯型热塑性弹性体（STPE）的表面修饰面临着巨大的挑战，因为典型的 ATRP 引发剂固定到 STPE 上需要在有机溶剂中进行，这会溶解并破坏 STPE 膜。在这项工作中，开发了一种简单的基于水的方法，将 ATRP 引发剂 Br 固定到苯乙烯-（乙烯-共-丁烯）-苯乙烯弹性体（SEBS）的表面上，SEBS 被选择作为 STPE 模型共聚物。通过这种方式，成功地从 SEBS 表面制备了乙二醇甲醚甲基丙烯酸酯（OEGMA）的功能聚合物刷。动力学研究表明，接枝密度与反应时间之间存在近似线性关系，表明链的增长与“受控”过程一致。直接连接到 SEBS-Br 表面苯环上的 CBr 键被证明是 SI-ATRP 的有效引发点。通过定义良好的 P（OEGMA）刷均匀覆盖表面，使 SEBS 薄膜具有优异的抗蛋白吸附和血小板黏附能力以及低溶血率。这项工作不仅可以操纵 SEBS 表面，大大提高其生物相容性，而且还为在基于苯乙烯的嵌段共聚物（SBC）表面上促进 SI-ATRP 铺平了道路。
