【摘要】 以聚苯乙烯-聚4-乙烯基吡啶(PS-b-P4VP)嵌段共聚物作为研究对象,采用DMF作为退火溶剂,以原子力显微镜(AFM)和透射电子显微镜(TEM)为表征手段,研究了溶剂退火后期溶胀薄膜中溶剂的去除速度对于薄膜相形貌的影响,发现通过改变溶剂去除速度可以有效的调控薄膜中的形貌.当薄膜厚度为35 nm时,DMF的快速挥发会导致薄膜中形成以PS为分散相的反转柱状相结构,当降低溶剂的挥发速度时,薄膜中形成了以PS为分散相的环状形貌,当进一步减缓挥发速度时,薄膜中将形成台阶状的片层结构;然而当薄膜厚度为55 nm时,溶剂退火后期薄膜中形成的是以P4VP为分散相的正常柱状相结构,在相同溶剂去除速度条件下薄膜相形貌变化较小.更多还原

【Abstract】 The influence of solvent removal rate on the morphology of DMF annealed cylinder-forming poly-( styrene-block-4-vinylpyridine)( PS-b-P4VP) thin films with different thickness is investigated by atomic force microscopy( AFM) and transmission electron microscopy( TEM). It is found that the final film morphology can be effectively modulated by controlling the solvent removal rate of the swollen film. When the film thickness was 35 nm,under fast solvent removal rate,long range ordered inverted parallel PS cylinders were obtained,as solvent removal rate decreased,the ring-shaped PS nanostructure formed in the whole film,and finally slow solvent removal rate resulted in terrace lamella morphology. Such morphological transformation is mainly due to kinetic effect and preferential affinity of annealing solvent for the minority block,which brings remarkable solvation effect. The unique ring-shaped morphology is caused by the shrinkage of the continuous P4 VP phase and bending of the PS cylinders. While when the film thickness was 55 nm,only P4 VP cylinder morphology was obtained under the same annealing condition and solvent removal rate. We consider that the low swollen rate will reduce solvation effect when the film is thick,in the mean time the effect of solvent removal rate on the final morphology is weakened.更多还原