Construction of hierarchical MoS2@TiO2 structure for the high performance bimaleimide system with excellent fire safety and mechanical properties

Abstract

Bismaleimide/diallyl bisphenol A (BD), a kind of allyl-modified bismaleimide (BMI) system, which is widely used in the fields of aviation, aerospace, machinery, and electronics. However, the further applications of BD are severely restricted by its high crosslink density, brittleness, and undesirable flammability. In order to overcome these drawbacks, a hierarchical MoS2@TiO2 structure is designed and synthesized to improve the mechanical and fire safety of BD, which are well matched with the high curing temperature and application temperature of BD. Specifically, with a relatively low loading of 2 wt% MoS2@TiO2, then the peak heat release rate (pHRR) and total heat release (THR) of BD composites are 314.25 kW/m2 and 53.58 MJ/m2, respectively, which are decreased by 32.5% and 15.0% in comparison to those of the pristine BD. Meanwhile, the TSR and yields of poisonous gases, especially CO and nitric oxide of BD/MoS2@TiO22.0 are greatly decreased which indicates that the fire safety is effectively enhanced. The impact strength of BD/MoS2@TiO22.0 sample is increased to 12.44 kJ/m2, which corresponding to a 96.8% compared with that of pure BD, and its storage modulus is 44462 MPa, a little higher than that of pure BD. Furthermore, Tg of BD/MoS2@TiO22.0 is increased to 326 °C with a lower cross-linking density while that of BD is 316 °C. Conclusively, this investigation demonstrates that the MoS2@TiO2 is a significant nano-additive for developing high-performance BD resins with excellent fire safety and mechanical properties, which provides a novel strategy for designing advanced BD composite material.