A facile strategy to simultaneously improve the mechanical and fire safety properties of ramie fabric-reinforced unsaturated polyester resin composites

To simultaneously improve the mechanical and fire safety properties of ramie fabric-reinforced unsaturated polyester resin (UPR) composites, a phosphorus- and nitrogen-containing silane coupling agent (TMSAP) was synthesized to be coated on surface of ramie fabrics. Then, the fabric/UPR composites were fabricated by hand lay-up/oven vacuum bag method after incorporating ammonium polyphosphate (APP) into UPR. In the vertical burning test, CF/UPR@APP10 can reach V-0 with only 10 wt% APP. Additionally, CF/UPR@APP10 composite exhibits the significant decrease on fire risks tested by cone calorimeter. For example, the significant 40.5% and 39.8% reduction in the peak heat release rate (PHRR) and total heat release (THR) values, accompanied with less toxic pyrolysis gases and more compact char layer. Moreover, compared to the neat composites, samples with TMSAP-coated fabrics show obviously enhanced tensile strength even though incorporating 10 wt% APP, implying the improved interfacial adhesion between fabrics and matrix.