PS／PMMA共混物薄膜的旋涂法制备及3D轮廓仪检测

Preparation of PS/PMMA Blend Film by Spin-coating Method and 3D Profiler Detection

采用旋转涂膜法在亲水性玻璃基底上制备了不同溶液浓度及不同质量分数的聚苯乙烯(PS)/聚甲基丙烯酸甲酯(PMMA)共混物薄膜,通过3D轮廓仪观测并分析了溶液浓度、质量分数对薄膜厚度、平均粗糙度的影响.结果表明:相同质量分数的共混物溶液所制得的薄膜,溶液浓度越大,平均厚度也较大,这是由于在旋涂过程中,对于同样体积的溶液,浓度较大的溶液挥发溶剂后残留的溶质量较多.相同浓度的共混物溶液所制得的薄膜,其平均厚度随着PS质量分数的增大而呈先减小后增大的趋势,在PS质量分数为30 wt%附近为最小,主要是由于PMMA的支链都是短链,能够较为容易地填充PS的空隙,从而形成共混状态,同时,PS分子支链上的苯环和PMMA分子的酯基都是极性疏水基团,因此在共混时有相互吸引作用.各浓度下PS/PMMA共混物薄膜的平均粗糙度随着溶质中PS质量分数增加呈先增大后减小的趋势,在PS质量分数为50 wt%附近其粗糙度都达到最大,这可能是由于PS和PMMA中的极性疏水基团相互吸引,使得分子链折叠隆起,导致薄膜的平均粗糙度增大,而PS质量分数约为50 wt%时,这种相互作用点较多,作用较强.同等情况下溶液浓度越大,所制备的共混物薄膜平均粗糙度越大,原因可能是溶液浓度较大时,分子链之间距离更近,能够有效引起分子链折叠隆起的相互作用点也更多.

In this paper, polystyrene （PS） / polymethylmethacrylate （PMMA） blends with different solution concentrations and differ- ent mass fractions were prepared on a hydrophilic glass substrate by spin coating, And the effects of solution concentration and mass fraction on film thickness and average roughness were analyzed by 3D profiler. The results show： the same mass fraction of the blend so- lution prepared by the film, the greater the concentration, the average thickness is also greater, which indicates that the concentration of the solution volatile solvent residue after the residual amount of more for the same volume of the solution, mainly due to the PMMA branches are short chains, can easily fill the gap of PS and form a blending state, at the same time, PS molecular chain on the benzene ring and PMMA molecular ester groups are polar hydrophobic groups, so there is mutual attraction when blending. The average rough- ness of PS/PMMA blends at each concentration increased first and then decreased with the increase of PS mass fraction in solute, and the roughness of PS/PMMA blends reached the maximum in the vicinity of PS mass fraction of 50 wt%, which may be due to PS and PMMA in the polar hydrophobic groups to attract each other, making the molecular chain folded uplift, resulting in the average rough- ness of the film increases, when the PS mass fraction is about 50 wt%, this interaction point is more and the effect is stronger. In the same case, the larger the solution concentration, the larger the average roughness of the prepared blend film, the reason may be that when the concentration of the solution is large, the distance between the molecular chains is closer, and the interaction point of the mo- lecular chain is also more effective.