Surface engineering with polydopamine coatings has been considered a promising surface functionalisation tool. However, it is difficult to control the self-polymerisation for polydopamine formation, which usually causes severe interparticle aggregation. In this study, polydopamine self-polymerisation was controlled by adjusting its reducing environment using a reductant (NaBH₄) to fabricate mixed cellulose ester (MCE)/polydopamine membranes. An oxidising environment using NaIO₄ was additionally tested as the control. The results showed that a thin polydopamine coating with small polydopamine particles was formed on the skeleton frameworks of the MCE membrane with NaBH₄, and the self-polymerisation rate was suppressed. The polydopamine coating formed in the reducing environment facilitated excellent water transport performance with a water permeance of approximately 400 L · m⁻² · h⁻¹ · bar⁻¹ as well as efficient organic foulant removal with a bovine serum albumin rejection of approximately 90%. In addition, the polydopamine coating with NaBH₄ exhibited both excellent chemical stability and anti-microbial activity, demonstrating the contribution of the reducing environment to the performance of the MCE/polydopamine membranes. It shows significant potential for use in water purification.

聚多巴胺涂层的表面工程被认为是一种很有前途的表面功能化工具。但是，难以控制聚多巴胺形成的自聚合，这通常会引起严重的颗粒间聚集。在这项研究中，通过使用还原剂（NaBH ₄）调节其还原环境来控制聚多巴胺的自聚合反应，以制造混合纤维素酯（MCE）/聚多巴胺膜。另外测试了使用NaIO ₄的氧化环境作为对照。结果表明，在带有NaBH ₄的MCE膜的骨架上形成了带有小聚多巴胺颗粒的薄聚多巴胺涂层。，并且自聚合速率被抑制。在还原性环境中形成的聚多巴胺涂层促进了卓越的水传输性能，水渗透率约为400 L·m ^-2 ·h ^-1 ·bar ^-1，并且有效去除有机污垢，牛血清白蛋白排斥率约为90％ 。另外，具有NaBH ₄的聚多巴胺涂层表现出优异的化学稳定性和抗微生物活性，证明了还原环境对MCE /聚多巴胺膜性能的贡献。它显示出在水净化中的巨大潜力。