Synergistic effect between novel triazine-based charring agent and modified kaolinite: An efficient system for fire hazard and aging suppression of epoxy resin

Abstract

A novel integrated charring agent was designed by reaction of 2,4-N-Tris (hydroxymethyl) methyl aminomethane (Tris), cyanuric chloride (CNC), and ammonium polyphosphate (APP). The obtained product Tris-CNC-APP were used with a synergistic agent of MoS2@Acid-Kaol (molybdenum disulfide grafted on the acidified kaolinite) together in epoxy resin (EP) to reduce the fire hazard and inhibit the release smoke. After adding 7%Tris-CNC-APP/3% MoS2@Acid-Kaol, the limiting oxygen index (LOI) of the EP sample was 36.1%, and the sample passed UL-94 V-0 rating. In the cone calorimeter test, the total heat release (THR) and total smoke release (TSP) were about half reduced compared with the control EP sample. The tensile strength of the control EP sample reached 56.5 MPa; and the impact strength was 3.1 KJ/m2. After 340 nm UV irradiation at 60 °C for 72 h, the tensile strength and impact strength decreased to 25.7 MPa and 0.6 KJ/m2, respectively, so that the aging EP sample became very brittle. However, for the sample containing 7%Tris-CNC-APP/3%MoS2@Acid-Kaol, the tensile strength was 43.3 MPa and the impact strength was 2.2 KJ/m2 after same UV aging. The reason was ascribed to the MoS2@A-Kaol and Tris-CNC-APP adsorbed some ultraviolet radiation, the EP was protected from UV aging. This work provided a feasible solution to reach high flame retardant grade and durable mechanical performance of EP products used outdoors with low filler loading.