Study On Halogen Free Flame Retardance And Toughening Of ABS

In this article,both flame retardance and mechanical properties were taken into consideration to develop a halogen free flame retardant ABS that was fit for actual application.This paper included two aspects of research,one was the halogen free flame retardance,the other was the enhancement of toughness..1.Red phosphorus and resorcinol bis(diphenyl phosphate)(RDP) were selected as the main flame retardant for ABS,respectively.Various char forming agents and synergistic agents were used to improve the flame retardance of ABS composites due to the poor char forming property of ABS itself.Oxygen index(OI) measurement,thermal degradation(TG) analysis and vertical burning test were employed to study the synergic role of MPPO in phosphorus-based flame retardant ABS.Experiment results show that MPPO can significantly increase the OI value of both ABS/RDP and ABS/Red phosphorus blends while only promoted the char forming rate of ABS/RDP system.When the content of MPPO was 30phr, the OI value of ABS/Red phosphorus(100/15) system reached from 23% up to 29%and FV-1 level was achieved.Also,there was a increase in the OI value of ABS/RDP(100/15)system from 22%to 29%with the additional content of 20phr of MPPO.2.Flame retardant ABS was toughened and compatibilized to cope with the degradation of toughness.Firstly,different compatibilizers were used to improve the compatibility between ABS and MPPO.Test results show that SMA has some effect in increasing the impact strength of ABS/MPPO blends.Secondly,the toughening effects of rigid particles, elastic particles and thermoplastic elastomers on ABS were studied by SEM and impact test.Results show that SBS is the most effective toughening agent.The Izod impact strength of ABS/Red phosphorus/MPPO(100/15/30) blends rose from 13.85J/m to 43.06J/m with the addition of 25phr of SBS.The charpy impact strength of ABS/RDP/MPPO(100/15/20) rose from 2.73 KJ/m~2 to 13.11 KJ/m~2 when the additional content of SBS was 25phr.The addition of SBS didn't affect the OI value of flame retardant ABS but expanded the time of fire extinguishment during the vertical burning test.