Phosphorus-nitrogen-type fire-retardant vinyl ester resin with good comprehensive properties

In this study, a series of fire-retardant vinyl ester resins (VERs) were obtained via the copolymerization of phosphorus-nitrogen-containing acrylate [1,3,5-triglycidyl isocyanurate (TGIC)-acrylic acid (AA)-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO)] and the widely used vinyl ester resin 901 (901-VER). The influences of the TGIC-AA-DOPO additive amount on 901-VER were comprehensively evaluated via the measurement of the flame retardancy, thermal performance, and mechanical properties. In the case of 30 and 40% TGIC-AA-DOPO, the thermosets acquired limited oxygen index values of 30.8 and 31.7%, respectively, and reached vertical burning (UL-94) ratings of V-1 and V-0, respectively. In addition, their peak heat-release rates, average heat-release rates, total heat release values, average effective heats of combustion, and total smoke productions decreased significantly. These results demonstrated the great progress of 901-VER in fireproofing performance. More importantly, the flame-retardant VER thermosets showed good thermal properties and castings, and glass-fiber-reinforced composites based on the developed fire-retardant VERs possessed comparable tensile strength, flexural strength, and better tensile modulus comparing to those based on neat 901-VER when the TGIC-AA-DOPO amount was no greater than 30%. From an integrated perspective, 901-VER with 30% TGIC-AA-DOPO was the best desired. The excellent flame retardancy, thermal performance, and mechanical properties promise the as-obtained VER important applicable values. (c) 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47997.