Abstract:

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-bPCVB 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.

Key words: Click chemistry, RAFT, electro-spinning, nanofiber