聚乙烯表面涂覆法长效亲水改性

Long effect hydrophilic modification of polyethylene surface coating

采用涂覆法在低密度聚乙烯(PE-LD)薄膜表面构建聚乙烯亚胺-甲基硅酸钠/聚丙烯酸-氯化钙(PEI-SMS/PAA-CaCl_2)长效亲水涂层。对比了不同质量分数的甲基硅酸钠和氯化钙对亲水性和耐水性的影响,探讨了干燥工艺对改性薄膜接触角和形貌的影响。结果表明,次表层中SMS和表层中的CaCl_2分别增强了所在层的疏水性和亲水性,其中,SMS作为过渡层起到连接PE膜和后续涂层的作用。当以SMS/PEI的质量比为1∶2作为第1涂覆层,CaCl_2/PAA的质量比为1∶12作为第2、4涂覆层,PEI作为第3涂覆层,使PE-LD薄膜的静态接触角从90°降低到30°左右,比仅使用PEI/PAA涂层低20～30°,使表面获得亲水效果,经过50℃水煮300 h,接触角增加到60～70°,实现了一定的耐水效果。

Polyethyleneimine-sodium methyl siliconate/polyacrylic acid-calcium chloride(PEI-SMS/PAA-CaCl 2)long effect hydrophilic coating was fabricated on the surface of low density polyethylene(PE-LD)film by coating method.The effects of various mass ratio of sodium methyl siliconate and calcium chloride on hydrophilicity and water resistance were compared,and then,the effects of different drying process on the surface contact angle and morphology of the modified film was explored.The results show that SMS in the subsurface layer and CaCl 2 in the surface layer respectively enhance the hydrophobic and hydrophilic of the layers.Among them,SMS is used as a transition layer to connect the PE film and subsequent coatings.When the mass ratio of SMS/PEI=1∶2 as the first coating layer,the mass ratio of CaCl 2/PAA=1∶12 as the second and fourth coating layers,and PEI as the third coating layer,and the static contact angle reduced from 90°to around 30°,which is 20~30°lower than that of the PEI/PAA coating alone,so that the surface obtain hydrophilicity.After boiling for 300 h,the contact angle was increased to 60~70°,achieving water resistance.