Effects of Modified Al2O3-Decorated Ionic Liquid on the Mechanical Properties and Impact Resistance of a Polyurethane Elastomer

In this work, a new composite material with excellent dynamic impact resistance and outstanding quasi-static mechanical properties was synthesized. The composite material is composed of a polyurethane elastomer and a novel nano-polymer. The nano-polymer was composed of silane coupling agent-modified alumina microspheres and functionalized ionic liquids by double bond polymerization. The universal testing machine and split Hopkinson pressure bar were used to characterize the compression behavior, strength and energy absorption of the composite materials under static and dynamic conditions. Additionally, the comprehensive mechanical properties of polyurethane elastomer with different nano-polymer loadings (0.5–2.5 wt.%) were studied. The results show that whether it was static compression or dynamic impact, the polyurethane elastomer with 1% nano-polymer had the best performance. For the composite material with the best properties, its compressive yield strength under the static compression was about 61.13% higher than that of the pure polyurethane elastomer, and its energy absorption of dynamic impacts was also increased by about 15.53%. Moreover, the shape memory effect was very good (shape recovery is approximately 95%), and the microscopic damage degree was relatively small. This shows that the composite material with the best properties can withstand high compression loads and high-speed impacts. The developed composite material is a promising one for materials science and engineering, especially for protection against compression and impacts.