Preparation and study of modified phytic acid/epoxy resin anti-corrosion coating

• Published in: Colloid and polymer science Vol. 302; no. 1; pp. 117 - 127
• Main Authors: Ju, Jun-Jie, Wang, Yang, Yu, Ming-Hua, Sun, Xin, Li, Wei-Li, Zhao, Zheng-Bai
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.01.2024; Springer Nature B.V
• Subjects: Aqueous solutions; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Coatings; Complex Fluids and Microfluidics; Corrosion; Corrosion inhibitors; Corrosion mechanisms; Corrosion prevention; Epoxy resins; Ethylene glycol diglycidyl ether; Failure rates; Food Science; Industrial development; Nanotechnology and Microengineering; Physical Chemistry; Phytic acid; Polymer Sciences; Shock resistance; Soft and Granular Matter; Tetrabutylammonium bromide; Anti-corrosion; Coating; Epoxy; Phytic acid
• ISSN: 0303-402X; 1435-1536
• DOI: 10.1007/s00396-023-05183-1

The anti-corrosion improvement of epoxy-based (EP) coatings through an eco-fridendly way is significant to industrial development. Phytic acid (PA) is a kind of natural corrosion inhibitor, but its use to enhance the anti-corrosion of EP is challenging due to their poor compatilibility. This problem is addressed by the modification of PA in this paper. First, PA is grafted to ethylene glycol diglycidyl ether (EGDE) to obtain modified PA (PA-EGDE) by the catalysis of tetrabutylammonium bromide. Subsequently, PA-EGDE is added to EP to fabricate PA-EGDE/EP coatings. When the PA-EGDE loading is 5 wt%, the PA-EGDE/EP coating exhibits best mechanical and anti-corrosion properties. The peeling force and adhesion failure rate are 2.03 MPa and 45.6%, and the hardness, flexibility and shock resistance are 2H, 1 mm and 50 cm, respectively. The corresponding E corr value of PA-EGDE/EP coating is -0.620 eV, which is much higher than that of EP coating (-0.797 eV); the impedance modulus is 10 8 Ω·cm 2 after immersion in 3.5 wt% NaCl aqueous solution for 30 days, which is much bigger than that of EP coating (10 6 Ω·cm 2 ). Moreover, the anti-corrosion mechanism of PA in EP coating is thoroughly discussed.