超亲水-水下超疏油聚氨酯海绵的制备及其油水分离性能研究

Preparation and oil⁃water separation performance of superhydrophilic⁃underwater superoleophobic polyurethane sponge

采用了一种简单、高效和环保的方法用于油水分离,即通过改进的Hummers法制备了氧化石墨烯(GO),以GO和壳聚糖(CS)为改性原料,以聚氨酯海绵(PU)为基体,通过两步浸渍法制备了超亲水-水下超疏油海绵(PUGO@CS)。GO的加入能够增加海绵表面的粗糙度和亲水性,CS的加入能增加海绵的亲水性和GO涂层的稳定性。改性PU具有良好的弹性性能、较好的热稳定性和吸水能力。油水分离性能测试表明,仅在依靠重力的作用下即可分离多种油水混合物,对各种油水混合物的分离效率可达95%以上;改性PU良好的可重复使用性使其在10次使用后的分离效率并未明显降低;在泵提供动外力时可实现无搅拌状态下的静态连续油水分离和搅拌状态下的动态连续油水分离;在磨损循环10次以后,改性PU仍能保持较高的油水分离性能。

A simple,efficient,and environmentally friendly method was adopted for oil⁃water separation.In this method,graphene oxide(GO)was first prepared by means of a modified Hummers method,and then a superhydrophilic⁃underwa⁃ter superoleophobic sponge was prepared through two⁃step impregnation using polyurethane sponge(PU)as a matrix and GO and chitosan(CS)as modifiers.The addition of GO increased the roughness and hydrophilicity of the sponge surface,while the incorporation of CS enhanced the hydrophilicity of the sponge and the stability of the GO coating.The modified PU sponge exhibited good elasticity,thermal stability and water absorption.The oil⁃water separation experi⁃mental results indicated that a variety of oil⁃water mixtures could be separated only under the action of gravity,and their separation efficiency could reach more than 95%.The modified PU sponge presented good reusability without a signifi⁃cantly reduction in the separation efficiency after reusing for 10 times.When the pump provided a dynamic external force,the static and dynamic continuous oil⁃water separation could be realized without stirring and with stirring,respec⁃tively.The high oil⁃water separation performance could be maintained for the modified PU sponge after wearing for 10 cycles.