ACS Appl Mater Interfaces. 2009 Feb;1(2):239-43. doi: 10.1021/am800143u.
A simple method for preparing solvent-resistant nanofibers with a thermal-sensitive surface has been developed by the combined technology of reversible addition-fragmentation chain-transfer (RAFT) polymerization, atom transfer radical polymerization (ATRP), electrospinning, and "click chemistry". Initially, well-defined block copolymers of 4-vinylbenzyl chloride (VBC) and glycidyl methacrylate (GMA) (PVBC-b-PGMA) were prepared via RAFT polymerization. Electrospinning of PVBC-b-PGMA from a solution in tetrahydrofuran gave rise to fibers with diameters in the range of 0.4-1.5 microm. Exposure to a solution of sodium azide (NaN(3)) not only affords nanofibers with azido groups on the surface but also leads to a cross-linking structure in the nanofibers. One more step of "click chemistry" between the PVBC-b-PGMA nanofibers with azido groups on the surface (PVBC-b-PGMA(-N3)) and alkyne-terminated polymers of N-isopropylacrylamide (NIPAM) (PNIPAM(AT)), which were prepared by ATRP, allows the preparation of a PVBC-b-PGMA nanofiber with thermal-sensitive PNIPAM brushes on the surface (PVBC-b-PGMA-g-PNIPAM). PVBC-b-PGMA-g-PNIPAM nanofibers exhibit a good resistance to solvents and thermal-responsive character to the environment, having a hydrophobic surface at 45 degrees C (water contact angle approximately 140 degrees) and having a hydrophilic surface at 20 degrees C (water contact angle approximately 30 degrees).
一种通过可逆加成-断裂链转移（RAFT）聚合、原子转移自由基聚合（ATRP）、静电纺丝和“点击化学”相结合的技术，开发出了一种具有热敏表面的耐溶剂纳米纤维的简单制备方法。首先，通过 RAFT 聚合制备了具有明确结构的 4-乙烯基苄基氯（VBC）和甲基丙烯酸缩水甘油酯（GMA）的嵌段共聚物（PVBC-b-PGMA）。将 PVBC-b-PGMA 从四氢呋喃溶液中静电纺丝得到直径在 0.4-1.5 微米范围内的纤维。暴露于叠氮化钠（NaN(3)）溶液不仅在纤维表面赋予了叠氮基团，而且还导致纤维中形成了交联结构。在表面具有叠氮基团的 PVBC-b-PGMA 纳米纤维（PVBC-b-PGMA(-N3)）和通过 ATRP 制备的端炔基 N-异丙基丙烯酰胺（NIPAM）聚合物（PNIPAM(AT)）之间进行“点击化学”的进一步步骤，允许制备表面具有热敏性 PNIPAM 刷的 PVBC-b-PGMA 纳米纤维（PVBC-b-PGMA-g-PNIPAM）。PVBC-b-PGMA-g-PNIPAM 纳米纤维表现出对溶剂的良好抗性和对环境的热响应特性，在 45°C 时具有疏水性表面（水接触角约为 140°），在 20°C 时具有亲水性表面（水接触角约为 30°）。
