Hydrogenated castor oil modified graphene oxide as self-thixotropic nanofiller in high solid polyaspartic coatings for enhanced anti-corrosion performance
By Liu, Qiang; Lei, Yang; Zeng, Qing; Li, Chenxi; Sun, Gang; You, Bo; Ren, Weidong
Published in Progress in Organic Coatings
2022
Abstract
To obtain eco-friendly high solid and excellent anti-corrosive polyaspartic (PAS) coating, a novel self-thixotropic nanofiller, hydrogenated castor oil modifying graphene oxide (HMGO) nanosheet, was fabricated and blended into the PAS coating to enhance its corrosion resistance. The self-thixotropic HMGO nanosheets were synthesized from 3-aminopropyltriethoxysilane (APTES) modified graphene oxide sheets by grafting the hydrogenated castor oil (HCO) with long alkyl chain molecular structure. HMGO could form a three-dimensional hydrogen network, separating and stabilizing the nanosheets in the polyaspartic coating matrix homogeneously, so that the HMGO/polyaspartic nanocomposite coating did not contain free low molecules or free inorganic nanofillers. Electrochemical impedance spectroscopy (EIS) and salt spray testing of HMGO/polyaspartic nanocomposite coatings with 86 wt% high solids have shown that corrosion protection properties have been significantly improved with the addition of self-thixotropic HMGO nanofiller. Compared with other nanofillers, including graphene oxide and APTES modified graphene oxide, HMGO nanosheets presented an impressive improvement in corrosion resistance of polyaspartic coatings. The superiority of HMGO/polyaspartic nanocomposite coating is owing to the self-thixotropic effect of HMGO promoted homogeneous distribution and high compatibility of HMGO nanosheets in polyaspartic polymer matrix.