Combining a bio-based polymer and a natural antifoulant into an eco-friendly antifouling coating

Biodegradable polymers are promising binders and carriers for natural antifoulants. In the present study, an antifouling (AF) coating was developed by adding a non-toxic AF compound (butenolide) to a bio-based and biodegradable poly(lactic acid)-based polyurethane. Mass loss measurement showed that the polymer degraded in seawater at a rate of 0.013 mg cm−2 day−1. Measurements showed that butenolide was released from the coatings into seawater over a period of at least three months. Both the concentration of butenolide in the coatings and the ambient temperature determined the release rate of butenolide. The results further demonstrate that incorporating rosin into the coatings increase the self-renewal rate of the polymer and facilitated the long-term release of butenolide from the coating. The results show that poly(lactic acid)-based polyurethane is a suitable polymer for butenolide-based AF coatings.可降解聚合物是天然防污剂极具应用前景的黏合剂与载体。本研究以生物基可降解聚乳酸（poly(lactic acid)）基聚氨酯为基材，添加非毒性防污化合物丁烯内酯（butenolide），制备得到防污（antifouling，AF）涂层。质量损失测试结果表明，该聚合物在海水中的降解速率为0.013 mg·cm⁻²·d⁻¹。检测显示，丁烯内酯可从涂层中释放至海水中，持续时长至少达三个月。涂层内丁烯内酯的浓度与环境温度共同决定了其释放速率。研究结果进一步证实，在涂层中掺入松香可提升聚合物的自更新速率，并促进丁烯内酯从涂层中长效释放。实验结果表明，聚乳酸基聚氨酯是制备丁烯内酯基防污涂层的适宜基材。