聚苯乙烯-co-聚(2,3,4,5,6-五氟苯乙烯)共聚物: 合成及其多孔薄膜的制备

利用原子转移自由基聚合(ATRP)方法, 分别在三氟甲苯、含氟离子液体以及三氟甲苯/含氟离子液体混合溶剂体系中合成了聚苯乙烯-co-聚(2,3,4,5,6-五氟苯乙烯)(PS-co-PPFS)共聚物, 通过¹H NMR、¹⁹F NMR、元素分析以及凝胶渗透色谱法(GPC)对所得聚合物的分子链结构和组成进行了分析和表征. 随后, 利用静态呼吸图法分别在CS₂, CHCl₃ 和CH₂Cl₂ 中制备了有序多孔薄膜, 用扫描电子显微镜(SEM)观察其表面形貌, 并与利用分子量大小相当的聚苯乙烯均聚物(PS)制备的多孔薄膜进行了对比. 研究结果表明: 在三氟甲苯和含氟离子液体溶剂体系中, 均可利用ATRP 聚合方法获得窄分子量分布的PS-co-PPFS 共聚物(M_n＝5200～7900 g·mol^-1, i>M_w/M_n＝1.12～1.22). 对聚合物薄膜的扫描电子显微镜(SEM)观察和分析显示: 分别以CS₂, CHCl₃ 和CH₂Cl₂ 作为溶剂, 利用静态呼吸图法均可制备出PS-co-PPFS 共聚物多孔薄膜. 然而, 与在CHCl₃ 和CH₂Cl₂ 中制备的PS 均聚物多孔薄膜的表面形貌不同的是, PS-co-PPFS 共聚物多孔薄膜呈现出无序排列、平均孔径大小不同的两种孔结构; 在CHCl₃ 中制备所得薄膜的孔结构有序性相对较好, 两种孔的平均孔径分别为0.75 和0.37 μm.

Polystyrene-co-poly(2,3,4,5,6-pentafluoro styrene) Copolymers:Synthesis and Fabrication of Their Porous Films

Well-defined polystyrene-co-poly(2,3,4,5,6-pentafluoro styrene)(PS-co-PPFS) copolymers were synthesized by atomic transfer radical polymerization(ATRP) in trifluorotoluene,fluorinated ionic liquid and trifluorotoluene/fluorinated ionic liquid solvent systems,respectively.The chain structure and component of such copolymers were characterized by 1H NMR,19F NMR,elemental analysis and GPC.Porous films of PS-co-PPFS copolymers were fabricated by static breath-figure method in CS2,CHCl3 and CH2Cl2,respectively.The morphologies of such porous films were observed by scanning electron microscopy(SEM) and compared with those of PS homopolymer with similar molecular weight.The results showed that PS-co-PPFS copolymers with narrow molecular weight distribution(Mn=5200～7900 g mol-1,Mw/Mn= 1.12～1.22) can be synthesized via ATRP in trifluorotoluene and fluorinated ionic liquid,respectively.The SEM observation indicated that PS-co-PPFS copolymer porous films can be fabricated with CS2,CHCl3 and CH2Cl2 as solvent,respectively.While,different from PS analogues,PS-co-PPFS copolymer porous films showed less ordered pore structures with two different average pore sizes.The pores of such film fabricated in CHCl3were in better order with two average pore sizes of 0.75 and 0.37 μm,respectively.