首先利用叶立德活性聚合和原子转移活性自由基聚合(ATRP)相结合制备了三个不同链段比的聚亚甲基-b-聚甲基丙烯酸甲酯(PM—b—PMMA)两嵌段聚合物.接着以它们为原料,利用静态呼吸图方法在四种不同溶剂中制备了一系列的具有蜂窝状表面的多孔薄膜,用扫描电子显微镜(SEM)观察了多孔薄膜的形貌.研究了溶剂、溶液浓度、聚合物链段长度及链段比等因素对多孔薄膜表面孔的大小和分布的影响.结果表明:当PM2k—b—PMMA2k嵌段聚合物浓度为3wt%、溶剂为二硫化碳(CS2)和二氯甲烷(CH2C12)时,可以通过静态呼吸图方法制备出孔径为纳米级(520nm)和微米级(1.1gm)的较为规整的多孔薄膜.多孔薄膜表面的孔径随PM—b—PMMA浓度的减小而增大;两嵌段聚合物中两个链段的长度及其链段比的变化对多孔膜表面孔径均产生较大的影响.
Three di-block copolymers polymethylene-b-poly(methyl methacrylate) (PM-b-PMMA) with different chain segment ratio were synthesized via the combination of living polymerization of ylides and atomic transfer radical polymerization (ATRP). Honeycomb-patterned films of such diblock copolymers were fabricated via static breath-figure method with four different solvents, respectively. The morphology of such porous film was observed by scanning electron microscopy (SEM). The effects of solvents, concentra- tion, PMMA segment and PM ~ PMMA ratio of diblock copolymers on the pore size and its distribution were investigated. Honeycomb-patterned films containing polyolefin segment with nanometer (520 nm) and micrometer pore (1.1 μm) were successfully fabricated via the static breath-figure (BF) method using carbon disulfide and dichloromethane as solvent at the concentration of 3 wt%. The pore size of honeycomb film increased with the decrease of polymer concentration. The length of PMMA segment and the PM : PMMA ratio of diblock copolymers play an important role in the morphology of polymer film.