Pan Weihao, Dong Jiahao, Gui Taijiang, Liu Ren, Liu Xiaoya, Luo Jing
The Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Lihu Street 1800, Wuxi 214122, China.
Marine Chemical Research Institute, State Key Laboratory of Marine Coating, Qingdao, Shandong 266071, China.
Soft Matter. 2022 Apr 6;18(14):2829-2841. doi: 10.1039/d2sm00062h.
A novel kind of inhibitor-loaded polyaniline (PANI) microcapsule was prepared by Pickering emulsion photopolymerization using polyaniline particles as the Pickering emulsifier. In our strategy, water-dispersible polyaniline nanoparticles were firstly synthesized using a micelle template method and used to stabilize oil-in-water emulsions, in which the oil phase contained photo-crosslinkable and pH sensitive monomers and a photo-initiator. Under UV light, the pH-responsive monomers underwent photo-polymerization and crosslinking and converted to microcapsule shells. During this process, polyaniline nanoparticles were trapped in the microcapsule shells, leading to the formation of PANI microcapsules. The structure and morphology of the synthesized PANI microcapsules were analyzed using FTIR spectroscopy, SEM, and EDX mapping. The inhibitor (mercaptobenzothiazole, MBT) was subsequently incorporated into the PANI microcapsule as a functional core and demonstrated pH-sensitive releasing behavior. With the anti-corrosive PANI as the microcapsule wall and the inhibitor MBT as the core, the as-prepared MBT loaded PANI (MBT@PANI) microcapsule could afford dual corrosion protection, allowing smart protection of metals when exposed to corrosive conditions. The MBT@PANI microcapsules were embedded in UV-cured coating for protecting steel. The corrosion protection performance of the coating with MBT@PANI microcapsules was evaluated using the electrochemical impedance spectroscopy technique and salt spray test, which demonstrated the synergistic inhibition effect of the PANI wall and the loaded MBT in improving anti-corrosion performance of the coating.
通过以聚苯胺颗粒作为Pickering乳化剂的Pickering乳液光聚合制备了一种新型的负载抑制剂的聚苯胺（PANI）微胶囊。在我们的策略中，首先使用胶束模板法合成了水分散性聚苯胺纳米颗粒，并用于稳定水包油乳液，其中油相包含可光交联和pH敏感的单体以及光引发剂。在紫外光下，pH响应性单体进行光聚合和交联并转化为微胶囊壳。在此过程中，聚苯胺纳米颗粒被困在微胶囊壳中，导致形成PANI微胶囊。使用傅里叶变换红外光谱（FTIR）、扫描电子显微镜（SEM）和能谱分析（EDX）映射对合成的PANI微胶囊的结构和形态进行了分析。随后将抑制剂（巯基苯并噻唑，MBT）作为功能核心掺入PANI微胶囊中，并表现出pH敏感的释放行为。以防腐聚苯胺为微胶囊壁，抑制剂MBT为核心，所制备的负载MBT的PANI（MBT@PANI）微胶囊可提供双重腐蚀防护，在金属暴露于腐蚀条件时实现智能防护。将MBT@PANI微胶囊嵌入紫外光固化涂料中以保护钢材。使用电化学阻抗谱技术和盐雾试验评估了含有MBT@PANI微胶囊的涂料的防腐性能，结果表明PANI壁和负载的MBT在提高涂料防腐性能方面具有协同抑制作用。
