Targeted control of unsaturated polyester resin curing kinetics to enhance network regularity and achieve impressive improvement in mechanical properties using gamma-aluminia: Exploring the relationship between curing kinetics and mechanical properties

Abstract

In this study, gamma-alumina (γ-Al₂O₃) particles were used to create a regular and strong network of unsaturated polyester (UP) resins by controlling the targeted free radicals and proportional adsorption of alkyd chains. The composite exhibited 80 %, 42 %, 46.39 %, and 60.31 % increases in the storage modulus, toughness, tensile strength, and flexural strength, respectively, compared with the Neat UP resin. A simultaneous study of the mechanical and physical characteristics and curing kinetics showed that the significant improvement in the mechanical and physical characteristics of the UP/Al 1 composite was due to the increase in the network regularity resulting from the targeted control of free radicals by γ-Al₂O₃ particles and the proportional adsorption of alkyd chains. The significant decrease in the values of K and E_D (Vyazovkin–Sbirrazzuoli diffusion factor (D-factor)) for the UP/Al 1 composite (-22.8 and 27.7 kJ/mol, respectively) compared to that of the Neat UP resin (-9.4, and 40.3 kJ/mol, respectively) confirms a significant increase in network regularity resulting from γ-Al₂O₃ particles.