Influence of acrylated guar gum on alkyd coating properties

Abstract

Purpose – The purpose of this paper is to evaluate the efficiency of acrylated guar gum (AGG) as an additive in alkyd resin for improved mechanical properties and to optimize the results of such an addition. Design/methodology/approach – For studying the effect of AGG on coating properties, guar gum was modified to various degrees of esterification and various compositions of alkyd systems were made by incorporating different concentrations of AGG. The mechanical and solvent absorption of the unmodified and modified alkyd systems were characterized. Findings – The incorporation of AGG into alkyd coating showed significant improvement of mechanical properties over the unmodified one. The modification caused an additional crosslink site through its unsaturation which led to increased crosslink density without phase separation of additive from the alkyd system which was confirmed by SEM scans. Research limitations/implications – The reactive additive, AGG used in the present study was synthesised using acryloyl chloride. Besides, it could also be synthesised from methacryloyl chloride and the effect of methyl substitution on water and solvent absorption could be studied. Practical implications – The method developed provided a simple and practical solution to improving the mechanical properties of alkyd coatings. Originality/value – The method for enhancing mechanical properties of cured alkyd system was novel and could find numerous applications in surface coatings.