Study On The Preparation Of Halogen-free Flame Retardant ABS And Its Flame Retardancy

Acrylonitrile-butadiene-styrene(ABS)resin is flammable and is accompanied by smoke during combustion,which limits the application of ABS in daily life.So it is necessary to treat it with flame retardation and smoke suppression.In this paper,the domestic and foreign literatures in recent years are reviewed,and the research status of halogen free flame retardant ABS is briefly described.In this paper,three intumescent flame retardant systems were used to treat ABS resin with flame retardation and smoke suppression.The main research contents are as follows:1.Using the Whitening Microencapsulized Red Phosphorus(WMRP)as synergistic agent,I composited flame retardant expandable graphite(EG)and silicon coated ammonium polyphosphate(Si-MCAPP)to produced the Novel Intumescent Flame Retardant ABS Composites.The flame retardant properties of composites were studied by means of limiting oxygen index(LOI),thermogravimetric analysis(TG)and conical calorimeter(CONE),and the fire hazard of composites was analyzed comprehensively.The experimental results show that when the add of EG/Si-MCAPP is 15wt%and the proportion of WMRP is 3wt%,the LOI value of is 30.2%,and the combustion grade UL-94 reaches V-0 grade.The peak heat release rate(pHRR)and total heat release(THR)decreased from 734.3 KM/m2 and 93.5 MJ/m2 to 206.2 KW/m2 and 60.7MJ/m2.The smoke release rate(SPR)and total smoke release(TSP)were also decreased by 76.4%and 47.9%,respectively,According to the fire hazard analysis,the fire spread index(FGI)of the composites decreased from 4.58kW/m2·s to 3.74kW/m2-s after the addition of WMRP and EG/Si-MCAPP.2.A new intumescent flame retardant was synthesized by using 1,3,5-Tris(2-hydroxyethyl)cyanuric acid(THEIC)as carbon source,Si-MCAPP as acid source and carbon source.The flame retardant properties of composites were analyzed by means of LOI?UL-94?TG?CONE and scanning electron microscopy(SEM),and the fire hazard of the composites was evaluated synthetically.The experiment shows that when the ratio of THEIC/Si-MCAPP is 1:2,the maximum LOI value of the composite is 29.7%.It passes through the UL-94 V-1 grade,and the carbon residue rate increases by 21.4%at 700 ?,and its pHRR decreases to 282.2kW/m2 and TSP decreases by 39.5%.SEM shows that the structure of the carbon layer becomes more compact and smooth after combustion.Fire hazard assessment shows that the fire risk of composite ABS is reduced.3.Preparation of Halogen-Free Flame retardant ABS Composites with TBCA and Si-MCAPP.The results show that when the proportion of TBCA/Si-MCAPP is 1:2,its LOI value is 28.2%,UL-94 is V-lgrade,pHRR is reduced from 734.3KW/m2 to 280.1 KW/m2,and THR also reduces 43.5MJ/m2 from 93.5MJ/m2.Based on the fire risk assessment,we can know its FGI dropped from 4.58kW/m2·s to 3.84kW/m2·s.The results show that the fire hazard of flame retardant materials is reduced.