溶液浓度和非溶剂比例对PVC膜形貌和疏水性能的影响

目的 研究溶液质量分数和非溶剂体积分数对PVC薄膜表面形貌和疏水性能的影响，以获得具有超疏水表面的PVC薄膜。方法 以四氢呋喃为良溶剂、乙醇为非溶剂，利用非溶剂诱导相分离的原理，采用旋涂法在玻璃基底上制备超疏水的聚氯乙烯（PVC）涂膜；通过对PVC样品的疏水性、表面形貌、结晶性能和热性能进行分析，探究溶液质量分数以及非溶剂的体积分数对PVC样品性能的影响。结果扫描电镜和接触角测试表明，添加一定体积分数的乙醇使得所制备的PVC样品形成了多孔膜层以及纳米级聚合物球粒，从而提高了PVC样品的疏水性。XRD测试结果表明，添加乙醇并不会改变PVC样品的无定形结构。结论 PVC溶液质量分数对所制备PVC样品的疏水性能和表面结构没有明显影响，乙醇体积分数为30%～40%时，可形成表面水接触角大于150°的超疏水表面。

Effect of Concentration and Non-solvent Content on Surface Morphology and Hydrophobicity of PVC Films

The work aims to study the effects of solution concentration as well as non-solvent content on surface morphology and hydrophobicity of PVC films, to obtain PVC films with super-hydrophobic surfaces. With tetrahydrofuran as a good solvent and ethanol as a non-solvent, super-hydrophobic polyvinyl chloride (PVC) coating films were prepared on a glass substrate by spin coating based on the principle of non-solvent induced phase separation. The effects of solution concentration as well as non-solvent content on the performance of PVC films were explored by the hydrophobicity, surface morphology, crystallization and thermal analysis. Scanning electron microscopy (SEM) and contact angle results demonstrated that the addition of a certain content of ethanol made the prepared PVC samples form porous films and nano-scale polymer spheres, and thus increased the hydrophobic property of PVC samples. The XRD results showed that the addition of ethanol did not change the amorphous structure of PVC films. It is found that the concentration of the PVC solutions have no significant effects on the hydrophobic property and surface structure of the prepared PVC films. Moreover, a superhydrophobic surface with a surface water contact angle greater than 150° can be formed when the volume ratio of ethanol to solvent is 30% - 40%.