Study On Preparation And Properties Of High Strength And Low Temperature Resistant Nylon 6 Composites

With the requirement of the new application condition such as the plastic parts beside the automobile engine and the pressure pump,it is imperative to develop high strength and low temperature resistant materials.Nylon 6 has high strength and low temperature toughness at the same time become the current research hotspots.This paper studied on rheological properties of the composite,the influences on performance of the composite due to extruding temperature and screw rotating speed,the kneading block number in mixing area of design machine screw combination in twin-screw extruder,which effect on the length of glass fiber and the mechanical properties of composites,we prepared the high performance nylon 6 composites.Through the rheological properties of each component,choice of glass fiber,toughening effect of toughening agent exerting influence on the properties of composites,finally decided with high and low viscosity nylon 6 as matrix,long glass fiber as reinforcing phase,toughening-1 agent and coupling agent(KH-550)as the blending system.We use the twin-screw extruder to prepare the nylon 6 composite.The following main conclusions are drawn from the experiments:The extrusion temperature of twin-screw extruder is set at about 235°C,nylon 6 composites have the highest impact strength;In the process of preparing the reinforcing and toughening nylon 6 blend composite material,the rotating speed of twin-screw extruder is suitable for medium and high speed;When of the kneading block number 6 group in mixing area,the nylon matrix and toughening agent has been fully dispersed,at the same time,the glass fiber was effectively coated,the impact strength of the prepared reinforced nylon 6 blend composite was maximum,and the uniformity of the data was the best,a better preparation technology of nylon 6 composite of high strength and low temperature resistant is:extruding temperature:235～250°C;screw rotating speed:300-350rpm;the kneading block number in mixing area:4-6;according to the above preparation technology,the nylon 6 composite can achieved the following excellent performance properties:Its Charpy notched impact strength on 23°C complete with 35KJ/m2,while 28KJ/m2 on-30°C,tensile strength was 128MPa,meanwhile,the bending strength reached 170MPa.The cross section of the prepared blend composite was characterized by SEM,the dispersion of the glass fiber in the composite is consistent with the influence of the extruding temperature of the twin-screw extruder and the number of kneading blocks in the mixing area on the properties of the composites.