Flame Retardancy Enhancement of Styrene–Butadiene Rubber Using Sepiolite Ionogels

Abstract

When using traditional flame retardants, rubber faces the trade-off between improving the flame retardancy and maintaining mechanical properties. Herein, a novel flame retardant of sepiolite-based ionogels (IL@ASep) with both flame retardancy and reinforcement functions is developed. This work explores the flame retardancy and mechanical properties of composites made from compound rubber filled with sepiolite (Sep) using different modification methods. The results indicate that the addition of IL@ASep helps to simultaneously improve the flame retardancy and mechanical properties of compound. The materials with IL@ASep have a limiting oxygen index of 30.7% and a modulus at 100% of 4.95 MPa, whereas the samples without fillers have a limiting oxygen index of 23.5% and a modulus at 100% of 3.77 MPa. compared to the original samples, the total heat release and peak heat release decreased by 55.3% and 39.2%, respectively. Furthermore, the method of adding ionic liquid (IL) is also expected to improve the flame retardancy and mechanical properties of other polymers.