【目的】为解决渔网在使用过程中存在的海洋污损生物附着问题。【方法】以生物基聚乳酸（ PLA）为软段，异佛尔酮二异氰酸酯（ IPDI）为硬段，再利用聚羧酸甜菜碱酯二元醇（ PCB）和 1，4-丁二醇进行扩链，制备了兼具降解和自生成两性离子功能的聚氨酯树脂。对树脂进行了表征，并研究了涂层的柔韧性、附着力、水接触角、水解降解速率以及在渔网上的实海防污效果。【结果】当 PCB含量为 20%时，该聚氨酯涂层具有良好的柔韧性和在聚乙烯（ PE）基材上的附着力，在海水中可自生成两性离子，并通过水解降解作用形成自更新表面。涂覆该涂层的 PE渔网在实海浸泡 3个月后，展现出明显的防污效果。【结论】上述工作为应用于海洋养殖领域防污涂料的开发提供了新的思路和借鉴。

［Objective］To solve the problem of marine biofouling on fishing nets during their use.［Methods］ A polyurethane resin with both degradability and self-generation of zwitterions wasprepared by using bio-based polylactic acid（PLA）as the soft segment，isophorone diisocyanate（IPDI） as the hard segment，and then extending the chain with poly（carboxybetaine）ester diol（PCB）and 1，4-butanediol. The number-average molecular weight and glass transition temperature of resin were characterized. Furthermore，the coating’s flexibility，adhesion strength，contact angle，hydrolytic degradation rate，and antifouling performance on fishing nets in a marine environment were investigated.［Results］When the PCB content is up to 20%，the polyurethane coating has good flexibility and adhesion to polyethylene（PE） substrate，and can self-generate zwitterions in seawater，forming self-renewingsurface through hydrolysis and degradation. The PE fishing nets coated with such coating show obviousantifouling performance after immersion in the sea for 3 months.［Conclusion］The above work providesnew ideas and references for the development of antifouling coatings applied in marine aquaculture.