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通过可逆加成-断裂链转移聚合(RAFT)活性自由基聚合方法制备了聚(苯乙烯-b-对氯亚甲基苯乙烯)(PS-b-PCVB)二嵌段共聚物,其中的氯亚甲基侧基经叠氮化反应后与丙炔醇进行点击(Click)反应,最终得到了含有1,2,3-三氮唑官能团的聚苯乙烯二嵌段共聚物(PS-b-PVBTM),核磁共振谱表征结果证明,PS-b-PCVB中的氯亚甲基完全转变成了1,2,3-三氮唑基团.PS-b-PVBTM在15 kV电压下进行静电纺丝,制得具有相分离现象的直径在100 nm左右的纤维.在90 ℃退火后纳米纤维表面变得光滑.红外光谱证明,在加热前后聚合物组成没有明显变化,而XPS结果显示退火后共聚物中C_(1s)振起伴峰降低,说明形成了电子转移络合物;XPS结果还表明,退火后表面张力较低的聚苯乙烯链段在表面富集.

The diblock copolymer of styrene and chloromethyl-4-vinyl-benzene(PS-b-PCVB) was obtained by means of reverse addition fragmentation chain transfer reaction(RAFT) living free radical polymerization. The chloromethyl groups in PS-b-PCVB were transformed into azidomethyl groups, and then into 1,2,3-triazol groups via click chemistry. The diblobk copolymer containing 1,2,3-triazol groups(PS-b-PVBTM) was thus obtained. The results from NMR spectra suggested a complete transformation from chloromethyl groups to triazol groups. PS-b-PVBTM in DMF was electro-spun at 15 kV, and nanofibers with obvious phase-separation and diameters of about 100 nm were obtained. The surface of the obtained nanofibers was smoothened after being annealed at 90 ℃. FTIR spectra indicate that the chemical structures of the nanofibers did not change during the thermal annealing process. XPS analysis shows that the shake-up peak of C1s decreased after annealing, which indicated charge transferring. XPS analysis also demonstrates that the low-surface-tension PS block gathered on the surface of the nanofibers after annealing.