Study On Toughened And Flame Retardant Modification Of Recycled PC And ABS Blends

Polycarbonate?PC?is a widely used engineering plastics with good mechanical properties,heat resistance and transparency.The decomposition temperature of polycarbonate is high,and it's difficult to degradation,which brings great pressure on environmental protection.Rational use of recycled polycarbonate both to respond to the requirements of the protection of the environment,but also to achieve the recycling of resources,with good social benefits.In this paper,PC and styrene-acrylonitrile-butadiene copolymer?ABS?were used as the main raw materials,methyl methacrylate-styrene-butadiene?MBS?as the toughening agent,brominated triazine and Sb₂O₃ as a flame retardant,blended and modified by twin screw extruder to prepare impact resistant flame retardant PC/ABS blends,which can be used to produce electrical box such as meter box.The effect of ABS content on the mechanical properties and thermal properties of PC/ABS blends was investigated.The effects of ABS content on the impact strength,tensile strength,fluidity and heat resistance of PC/ABS blends were investigated.The results show that the processing temperature of PC/ABS blends decreases and the melt flow is improved with the increase of ABS content.When the ABS content is 30%,the comprehensive mechanical properties of PC/ABS blends are excellent,and the processing flow is good,and the molding temperature is reduced by 20?c ompared with the PC processing temperature.Secondly,the mass ratio of PC/ABS was 70/30,and the content of MBS was changed.A series of MBS toughened PC/ABS blends were prepared to study the effect of MBS on the impact strength of PC/ABS blends.The results show that the impact strength of the toughened PC/ABS blends increases first and then decreases with the increase of MBS content.When the content of MBS is 8%,the impact strength of the material is 49.76 kJ/m²and the tensile strength is 57.52 kJ/m².Compared with the non-toughened PC/ABS blends,the impact strength is increased by 55.60%.Tensile strength decreased by only 3.40%.Finally,on the basis of toughening PC/ABS blends,the effects of brominated triazine and Sb₂O₃ on the flame retardancy and mechanical properties of the PC/ABS blends were investigated.The flame retardancy of PC/ABS blends reached UL94 Level V-2,V-1 and V-0when the flame retardants were 5%,10%and 15%of the total mass of the blends,respectively.However,with the increase of flame retardant content,the mechanical properties of the blends will be reduced to some extent.When the content of brominated triazine and Sb₂O₃ was 15%,the impact strength of the blends was 42.32 kJ/m2,which was 18.05%lower than that of the PC/ABS blends after toughening,which was 32.33%higher than that of PC/ABS blends before the toughening,still has a good toughness.The recovery of PC and ABS,MBS toughening agent and brominated triazine and Sb₂O₃were modified by twin screw extruder to improve the processing flow of PC and reduce the processing temperature of PC.The prepared PC/ABS blends had highly Impact strength and good flame retardant performance.On the whole,this method of recycling PC is simple and easy to process,low cost,environmentally friendly,economical use of resources,with good social and economic benefits.