Nuttiwan Thamprasom. Effect of triphenylphosphate flame retardant on properties of polybenzoxazines. Master's Degree(Chemical Engineering). Chulalongkorn University. Center of Academic Resources. : Chulalongkorn University, 2010.
Effect of triphenylphosphate flame retardant on properties of polybenzoxazines
Abstract:
To enhance flame retardancy of polybenzoxazines, non-halogenated phosphorus compound has been evaluated for its potential flame retardant. In this research, the resulting flame retardanted polybenzoxazines were prepared by mixing phosphorus flame retardant with three types of arylamine-based benzoxazine resins. Their fire resistance, thermal, and mechanical properties were investigated. The weight ratios of benzoxazine resins/TPP were varied to different phosphorus content. DSC results indicated that, in the presence of TPP, the onse and maximum temperature of the exothermic peak due to the ring opening polymerization of benzoxazine resins shifted to lower temperature. From TGA results, The degradation temperatures at 5% weight loss of polybenzoxazines were reduced. All polybenzoxazines possessed relatively high char yield, which increased as the TPP content increased. This implied that their flame retardancy could be enhanced. The flame-retardancy of these thermosets was evaluated by limiting oxygen index (LOI) and and UL-94 vertical tests. Upon adding 10 wt% of TPP, LOI increased from 23.5, 23, 22 to 26, 25, 24, for BA-a, BA-mt, and BA35x, respectively. Furthermore, the flammability was found to be in an order of BA-a