Study On Preparation And Performance Of Organic Phosphonate/Polyurethane Flame Retardant Elastomer

Polyurethane elastomer(PU)is a widely used polymer material.But pu Is easy to burn,the combustion process has drops.Phosphorus-containing compounds are a widely used flame retardant.The research shows that the flame retardant structure and flame retardant effect of phosphorus-containing compounds in polymers are closely related to the chemical price of phosphorus.In this paper,a flame retardant agent---DPMP is selected as the flame retardant of the PUs.The flame retardant performance and flame retardant engine of DPMP to PU are discussed.On this basis,clay is selected as the co-agent of DPMP,and clay’s influence on the flame retardant performance of DPMP/PU system is discussed.Analysis of flame retardant behavior by extreme oxygen index test(LOI),vertical combustion test(UL-94),micro-volume heat test(MCC),thermal weight loss test(TGA),thermal weight-infrared joint(TGA-FTIR)The gas composition in the process of thermal decomposition is characterized,and the shape,elements and solid-phase composition of the combustion residue are analyzed by scanning electron mirror(SEM),Fourier Transform Infrared Spectroscopy(FTIR),and X-ray photoelectronic energy spectrometer(EDS).The flame retardant mechanism of DPMP and Clay’s flame retardant co-effect mechanism of DPMP/PU system are put forward.The results showed that adding DPMP with a mass percentage of 10 wt% increased the LOI value of PU from 23% to 29.3%,and the system passed UL-94 V1 only because the combustion process was accompanied by drops.MCC data show that adding DPMP reduces the heat release rate of the PU and the overall thermal release rate by 11.4% compared to the pure PU,with a maximum thermal release rate of 10 wt% DPMP/PU.The total heat release decreased by 10.8%,and the results of gas phase decomposition products and residual carbon morphology and structure analysis showed that DPMP was mainly gas phase flame retardant in PU.Clay is a flaky structural inorority that,when added to Clay,effectively prevents dripping during the DPMP/PU combustion process.1 wt% Clay allows the 10 wt.% DPMP/PU system to burn through the UL-94 V0.Clay prevents PU melts from dripping in the system.In addition,it also increases the tightness of the carbon layer and increases the amount of residual carbon.A tight,strong carbon layer prevents heat from passing between the gas phase and the condensed phase.Reduce the amount of combustibles in the gas phase.At the same time,it prevents oxygen and heat in the gas phase from spreading to the condensed phase,which causes the combustion to increase.