A Novel Method for Significant Enhancement of the Mechanical Properties of Unsaturated Polyester Resin Nanocomposites Through Targeted Control of Curing Kinetics and Network-Particle Interaction Utilizing Metal-Organic Frameworks MIL-53-NH₂(Al)

This study used MIL-53-NH₂ (M53) particles to improve the dynamic-mechanical properties of unsaturated polyester resin (UPER). The results of dynamic and mechanical analyses (DMA) showed a significant increase (approximately 70%) in the storage modulus of UPER containing 0.5 wt% of M53(UP/0.5M53) in comparison to the neat UP resin (NUPR). The significant increase in modulus is not only due to the particle-resin attractive interactions but also factors such as controlling radical reactions, adsorption, and the purposeful release of free radicals, which can improve the network density and regularity of the UPER network and, as a result, increase the storage modulus. On the other hand, investigation of the curing kinetics using differential scanning calorimetry (DSC) showed an increase in the dominance of the diffusion phenomenon in UP/0.5M53 compared to NUPR. The increase in the dominance of the diffusion phenomenon confirms the increase in the network density and resin regularity after the addition of M53 particles. In addition, the significant decrease in the K(-9.5 to -13.1) and E_D(40 to 18 kJ/mol)parameters of the Vyazovkin-Sbirrazzuoli diffusion factor(VS-df) for UP/0.5M53 compared to NUPR indicates an increase in the network density and resin regularity after the addition of M53 particles.