Microwave Solvothermal‐Evaporation Synthesis of Flower‐Like ILs‐SnS ₂ : Improving Fire Safety and Mechanical Property for Epoxy Resin

ABSTRACT A novel flower‐shaped ionic liquid/tin disulfide flame retardant (ILs‐SnS 2 ) was prepared using microwave hydrothermal synthesis (160°C, 80 s) combined with solvent evaporation method. The synthesized flame retardant was added to epoxy resin via the curing method, and its effect on flame retardancy and mechanical properties of the composite material was studied. Compared to pure EP (1185.9 kW/m 2 ), the addition of 3 phr SnS 2 , BF 4 ‐SnS 2 , and PF 6 ‐SnS 2 resulted in a decrease in peak of heat release rate values to 853.4, 735.2, and 859.6 kW/m 2 , respectively. The excellent flame retardant performance was attributed to physical isolation, catalytic carbonization, and gas‐phase dilution. In addition, based on the interface interaction between ionic liquids and epoxy resin, compared with EP/SnS 2 , the fracture elongation of EP/ILs‐SnS 2 increased from 9.04% to 11.24% and 11.72%, the tensile strength increased from 41.32 to 44.54 MPa and 44.0 MPa, and the impact resistance increased from 7.72 to 10.92 and 9.11 kJ/m 2 , which were effectively improved. According to Table S1, this method can be synthesized rapidly in 80 s. The research on the modification of ionic liquid into flame retardants and compatibilizers provides a new approach.