海藻酸钠载体微球的制备及改性水性涂层防腐蚀机理研究

Preparation of sodium alginate microspheres and study on anti-corrosion mechanism of modified water-based coatings

近年来,微胶囊技术在涂层自修复领域的应用受到广泛关注。将缓蚀剂酒石酸钠负载到海藻酸钠微球并添加到水性涂层中,研究包覆缓蚀剂酒石酸钠的载体微球在pH值分别为3,7和9时,缓蚀剂的释放能力及涂层防腐机理。结果表明,缓蚀剂酒石酸钠成功包覆到载体微球中,包封率为30.65%。缓蚀剂酒石酸钠在不同pH值环境下从载体海藻酸钠微球中的释放速率自大到小排序为pH值=9的速率>pH值=3的速率>pH值=7的速率;将包覆酒石酸钠的海藻酸钠微球按照5%的质量比分别添加到水性聚丙烯酸涂层中,随着涂层浸泡时间的增加,电荷转移电阻逐渐增大,这表明改性涂层具有了自修复防腐蚀性能。海水浸泡试验进一步证实了包覆酒石酸钠的海藻酸钠微球改性后的涂层防腐蚀性能得到了提高。

In recent years,the application of microcapsule technology in the field of coating self-healing received widespread attention.The corrosion inhibitor sodium tartrate was attached to the sodium alginate microspheres and added to the water-based coating;then,the release ability of the inhibitor and the corrosion mechanism of the coating were studied at pH values of 3,7 and 9.The results showed the inhibitor sodium tartrate was successfully encapsulated into the microspheres,with an encapsulation rate of 30.65%;the release rate of sodium tartrate from sodium alginate microspheres under different pH values met pH=9>pH=3>pH=7.When the sodium alginate microspheres coated with sodium tartrate were added to the water-based polyacrylic acid coating at a mass ratio of 5%,charge transfer resistance gradually increased with the extension of the coating immersion time,indicating the self-healing capabilities of the modified coating.The seawater immersion test further confirmed that the corrosion resistance of the coating was improved after the modification.