PC plastic molding conditions
PC can be injection, extrusion, molding, blow molding, hot forming, printing, bonding, coating and machining. The most important processing method is injection molding.The product must be pre-dried before forming, and the moisture content should be less than 0.02%. The processing of small amount of water at high temperature will cause the product to produce white color, silver wire and bubbles. PC has a considerable ability to force high elastic deformation at room temperature.The impact toughness is high, so cold pressing, cold drawing, cold roll pressure and other cold forming process can be carried out.The molecular weight of PC for extrusion should be more than 30,000, the gradual compression screw should be adopted, the length diameter ratio is 1:18 to 24, the compression ratio is 1:2.5, the extrusion blow molding can be used, injection - blow, injection - pull - blow molding high quality, high transparent bottle.There are many kinds of PC alloys, such as high viscosity of PC melt (machinability) and easy stress cracking of products. PC forms alloys or blends with different polymers to improve material performance.Specific have PC/ABS alloy, PC/ASA alloy, PC/PBT alloy, PC/PET alloy, PC/PET/elastomer blend, PC, PC/MBS blend/PTFE alloy, PC/PA alloy, etc., there are two kinds of material performance advantages, and lower costs, such as PC/ABS alloy, PC main contribution to the high heat resistance, good toughness and impact strength, high strength, flame retardancy, ABS can improve the formability and apparent quality, reduce the density.Properties of polycarbonate and molding parameters are shown in table: (for reference only) density of 1.18 ~ 1.20 mold temperature 50 ~ 80 shrinkage ratio of 0.5 ~ 0.8 injection pressure preheating temperature of 80 ~ 130 ° C / 110 ~ 120 parameters injection time of 20 ~ 90 times/h 8 ~ 10 0 ~ 5 material barrel temperature/high pressure time after the period of 210 ~ 240 ° C cooling time of 20 ~ 40 ~ 190 90 midway through 230 ~ 280 total cycle in 240 ~ 285 screw revolution 28The nozzle temperature is 240~250 using the injector type screw type