Strength and adhesion properties of acrylic polyol‐epoxy polyol resin protective coating on mild steel substrate

Abstract

PurposeThe purpose of this paper is to improve the strength and adhesion properties of modified acrylic polyol resin using epoxy polyol resin (DEGBA).Design/methodology/approachThe hybrid systems were prepared by blending acrylic resin with epoxy polyol resin (Diglycidyl Ether of Bisphenol‐A, DGEBA) and polyisocyanate resin as hardener in various weight ratios with xylene as a solvent. The samples were applied on the pre‐treated cold rolled mild steel panels. The mechanical property of the blend has been evaluated using rapid impact tester (Sheen 806/40) and adhesion tester (Sheen Cross‐Hatch 750). Intended panels were checked for cracks using Dino‐Lite and Pinhole detectors (Elcometer 270/4). Crossed panels were observed for damages using digital polarized microscope (Dino‐Lite, AM413ZT). The thermal properties were studied using thermal analysis system (TGA TA‐Q500, DSC TA‐Q200).FindingsThe modification of acrylic polyol resins using DGEBA showed significant improvement of toughness compared to pure acrylic polyol resins. The blending systems with 10 wt percent of DGEBA and 90 wt percent of acrylic resin showed good adhesion and impact resistance properties on mild steel substrate.Research limitations/implicationsThe hybrid coating system has contributed to the basic conceptual understanding of the corrosion protection property, focusing mainly on recent research available.Practical implicationsThe blending method provided a simple and practical solution to improve the toughness of acrylic polyol resins.Originality/valueThe method for enhanced toughness of cured acrylic was novel and functionality of coating critically depends on adhesion between the coatings and underlying metal substrate.