Ecofriendly automobile base coats derived from castor oil: evaluation of nano silica reinforcements on the performance characteristics of coatings

Abstract

Purpose The purpose of this study is to reduce the application of petroleum in automobile paint industry by replacing it with bio-based castor oil along with nano fillers to synthesize automobile base coat (BC). Design/methodology/approach Bio-based polyurethane (PU) coating applicable in automobile BC was synthesized by using modified castor oil incorporated with nano silica (NS) and titanium-based pigment particles. The influential characteristics of the coating was studied by carrying out cross-cut tape test, abrasion resistance, pencil hardness, lap-shear, thermo gravimetric analysis, differential scanning calorimetry, dynamic mechanical analysis and acid, alkali and oil resistance tests. Findings Incorporation of NS particles, along with titanium-based pigment particles in optimized ratio into the paint matrix, increases the mechanical, chemical and oil resistance properties and hydrophobicity of the BC, and the findings are compared with the petro-based commercial BC. Research limitations/implications There is no significant improvement in thermal properties of the paint matrix, and it is less thermally stable than the commercial BC. Practical implications The paint developed through this study provides a simple and practical solution to reduce the petro-based feed-stock in automobile paint industry. Originality/value The current work which reports the use of ecofriendly PU BC for automobile paint applications is novel and findings of this study are original.