聚醚硅油表面迁移行为对聚苯乙烯表面极性的影响

利用变角衰减全反射傅立叶变换红外光谱(ATR-FTIR)法和接触角,分析了聚醚硅油在聚苯乙烯共混物薄膜表面的选择性富集行为及对其表面结构和表面极性的影响,认为接触介质的表面性质是影响共混物中各组分产生选择性迁移扩散的重要影响因素.强极性介质的诱导作用可以在共混物表面层中产生剧烈变化的浓度梯度,而弱极性介质所产生的表面浓度梯度比较缓和.

THE IMPROVEMENT OF POLARITY OF POLYSTYRENE SURFACE BY THE SELECTIVE SURFACE MIGRATION OF POLYETHER SILICOME OIL

The selective aggregation of the polyether silicone oil(PSO)on the surface of polystyrene(PS)films was investigated by using the contact angle measurement and the attenuated total reflectance Fourier transform infrared spectroscopy.By utilizing the “surface target" effect of the chain segments of the silicon oil,the applied efficiency of the macromolecular surface modifier(PSO)was enhanced greatly.Because the chain segments of silicone oil could preferential aggregate on the surface of the PSO/PS blends,it led the polyether chain segments migrated on the surface of the films which took the climacteric role in improving the hydrophilicity of the films.It was also found that the preferential surface migration of PSO was heavily depended on the surface properties of the contact medium.Compared with the different mechanisms of the surface migration,the inducement of polar groups on substrates(glass or polyimide)made more chain segments of polyether aggregated on the blends surface,and the polar portion of the surface energy of the films was increased greatly.Whatever the samples were annealed by polyimide or polytetrafluoroethylene,the concentration of silicon chain segments in the surface was much higher than that in bulk.It certified that the “surface target” effect of the silicon oil chain segments was much intensive in the blends.In the process of surface migration,the abundant surface structure was reconstructed.Because the inducement of the polar substrates was attenuated quickly as the operating distance increased,the surface concentration gradient of PSO declined acutely when the samples were annealed on glass or polyimide.But the surface concentration gradient of PSO altered gently when the samples were annealed on polytetrafluoroethylene.