High-performance gum rosin-modified hyperbranched vinyl ester resin derived from multifunctional pentaerythritol

In this article, gum rosin-based hyperbranched vinyl ester resin (VPEMPAE) was synthesized from maleic anhydride-modified gum rosin adduct (MPA). This adduct (MPA) was reacted with pentaerythritol to obtain esterified adduct (PEMPA). The PEMPA adduct was epoxidized using epichlorohydrin and KOH as a catalyst to give epoxy resin (PEMPAE). The epoxide rings were then reacted with methacrylic acid to synthesize vinyl ester resin (VPEMPAE). The lignin modeled compounds (LMCs), methacrylated eugenol (ME), and methacrylated guaiacol (MG) were used as bio-based reactive monomers for vinyl ester resin. The chemical structures of all the products were studied using FT-IR, H-1-NMR, C-13-NMR, and DEPT-135 degrees spectroscopic analysis. The dynamic curing study of cured samples was done using DSC. Thermogravimetric analysis of these samples was performed using TGA at a heating rate of 10 degrees C min(-1). Mechanical properties such as compression, flexural, and tensile strengths of VPEMPAE samples were also determined using a universal testing machine. Some preliminary coating tests were also performed to determine the chemical resistance of these cured resins and morphological studies on these coatings were also conducted using SEM. The results of this study showed better performance of rosin-derived vinyl ester resin cured with reactive diluent ME as compared to MG and commercially based styrene.

Automated summary

In this study, high-performance rosin-based vinyl ester resin was synthesized through modification and esterification of gum rosin adducts, with evaluation of mechanical properties and chemical resistance. Results indicated superior performance of rosin-derived vinyl ester resin cured with methacrylated eugenol compared to other reactive diluents.