利用等离子体技术研究聚苯乙烯表面的接枝聚合反应

Studies on Graft-polymerization of Polystyrene Surface by Plasma Technology

用O2等离子体对聚苯乙烯(PS)进行预处理,再用Ar等离子体引发N-乙烯基吡咯烷酮(NVP)在其表面接枝聚合.通过接触角(CA)及表面自由能(SE)分析,探讨了O2等离子体预处理条件对PS表面自由能的影响,确定了预处理的最佳条件.通过衰减全反射红外光谱(ATR-FTIR)、X射线光电子能谱(XPS)和动态接触角(DCA)分析,比较了O2等离子体预处理前后和接枝聚合前后PS的表面组成及表面性能,实验结果表明,利用等离子体技术能成功地将NVP接枝聚合于PS表面,接枝聚合后的PS表面由于极性高分子链和粗糙度的增加,亲水性增强,水滴易在其表面铺展.由于接枝聚合后PS表面的高分子链在水中发生重构,使后退角降低幅度较大,接触角滞后现象明显.

Polystyrene （PS） was pretreated by O2 plasma, then N-vinylpyrrolidone （NVP） was graft-polymerized on PS surface in the Ar plasma environment. The effect of O2 plasma pretreatment on surface free energy of PS was investigated by means of contact angle （CA） and surface free energy （SE） measurements. As the result, the optimum conditions of 02 plasma pretreatment on PS surface were power 50 W, pressure 40 Pa and time 3 rain. The surface composition and properties of the modified PS between pre- and post O2 plasma treatment and graft polymerization were studied by ATR-FTIR, XPS, and DCA measurement. The results show that the NVP is successfully graft-polymerized on PS surface by plasma technology and the hydrophilicity of the modified PS surface markedly increased. The PS surface graft-polymerized was easily spreaded by water due to the increase of polar group and roughness. Further, the receding angle decreased obviously and the contact angle hysteresis was significant because of the reconstruction of the polymer chain on the PS surface.