表面增强拉曼光谱研究高分子共混物薄膜相结构

采用拉曼光谱法研究了由聚苯乙烯(PS)/聚甲基丙烯酸甲酯(PMMA)的四氢呋喃(THF)溶液在玻璃基板上旋转涂膜得到的共混物薄膜。应用显微共焦拉曼光谱,根据PS在1604,1585cm-1处苯环的伸缩振动峰和PMMA在1728cm-1处羰基的伸缩振动峰,可以确定薄膜(厚度约为800nm)表面海岛状相结构的组分分布信息。另外,还对210℃下PS/PMMA(30/70)共混物薄膜退火过程中表面的变化进行了分析。采用表面增强拉曼散射效应对高聚物的增强作用得到了薄膜(厚度约为400nm)的Raman光谱,并且成功地对其组成进行了分析。

Investigation of Phase Morphology of PS/PMMA Blend Thin Film by Surface Enhanced Raman Scattering

Polystyrene/poly (methyl methacrylate) (PS/PMMA) was studied after the thin films were prepared on glass substrate by spin-coating from THF. Raman spectroscopy combined with microscopy was used to obtain information on the morphology and structure of the thin films. From the relative intensities of the peaks around 1 604 and 1 585 cm(-1) due to stretching of benzene rings, and 1 728 cm(-1) due to stretching of C=O for PS and PMMA respectively, the authors could define the composition of the domains in the sea-island-like phase-separated structure in the microscopic image. Furthermore, the structure evolution was followed by Raman spectroscopy during the in-situ annealing of PS/PMMA (30/70) blend thin films at 210 degrees C. And the effect of SERS on the PS thin films was also discussed.