The first section outlines the English name of polycarbonate polycarbonate, called PC. Commonly referred to as bisphenol A polycarbonate are means polycarbonate and modified varieties. As only five transparent plastic products, PC is a non-crystalline engineering plastics, with a particularly good impact strength, thermal stability, gloss, inhibit bacterial properties, flame retardant properties and fouling resistance. PC notched impact strength (Notched Izod Impact Stregth) is very high and very low shrinkage rate, usually 0.1% ~ 0.2%, PC has good mechanical properties, but illiquid, so the injection molding process the material is relatively difficulties. In the selection of PC material which material, we should expect the final product as a benchmark. If the plastic parts require high impact resistance, then use a low turnover rate of PC material, on the contrary, you can use the high turnover rate of PC material, which can optimize the injection molding process. Section II features 1, physical and chemical properties of pure PC resin is an amorphous, tasteless, odorless, non-toxic, transparent thermoplastic polymer molecular weight is generally within the range of 20,000 to 70,000, the relative density of 1.18 to 1.20, a glass transition temperature of 140 ~ 150 ° C, melting range 220 ~ 230 ° C. Polycarbonate has a certain resistance to chemical resistance, oil resistance. Since the non-crystalline polycarbonate inter molecular piling-dense, aromatic hydrocarbons, chlorinated hydrocarbons, organic solvents can swell or dissolve so as to cause solvent cracking. Alkali resistance is poor. 2, the mechanical properties of the polycarbonate of excellent mechanical properties, especially in its strength and dimensional stability to combat, in a wide temperature range can maintain high mechanical strength, the drawback is the fatigue strength and abrasion resistance poor, easier to produce stress cracking phenomenon. 1) Impact strength: the impact strength of polycarbonate plastics as well as all the common thermoplastics are very prominent, its value and 45% glass fiber reinforced polyester PET similar. The main factors affecting the impact strength of the polycarbonate has a molecular weight, notch radius, temperature and additives. 2), creep resistance: polycarbonate thermoplastic plastic creep resistance is quite good, even as nylon and POM. Dimensional changes and changes due to water absorption caused by cold are very small, which is an important indicator of its excellent dimensional stability. 3), fatigue strength: the ability to resist cyclical stress cycle effect polycarbonate poor. 4), abrasion wear resistance: compared with other engineering plastics, polycarbonate larger coefficient of friction, wear resistance is poor. 3, thermal decomposition temperature of 300 ° C above the long-term operating temperature up to 120 ° C, while it has good resistance to cold, brittle temperature -100 ° C, long-term use temperature range is -60 ~ 120 ° C. 4, the electrical properties of the polycarbonate molecular polarity small, high glass transition temperature, low water absorption, and therefore has excellent electrical insulation properties, approaching or equivalent has been regarded as excellent electrical insulation properties of PET. Electrically insulating polycarbonate closely related temperature, humidity, electric field frequency and thickness of the article. 5, aging resistance and flame resistance polycarbonate heat aging performance is quite good, if its film was left in air for a long time heating, little change in its performance. However, if a long period of sunlight, oxygen, water vapor action, especially coupled with the high temperature, which in turn contain certain impurities cases, it can cause degradation. Polycarbonate is combustible, pale blue flame, black smoke, oxygen index was only 25%, away from the fire self-extinguishing. Generally the halide, magnesium hydroxide, phosphoric acid and red phosphorus modified to improve the flame retardancy. 6, the optical properties of the polycarbonate material is non-crystalline, pure colorless and transparent polycarbonate, having good transparency, surface hardness because of their poor wear resistance is not good, the surface easily scared affect their light transmittance. Application Section 1, automobile PC for automotive lighting systems, dashboard systems and interior systems, used as a pre-bowl with strengthening ribs around the car baffles, reflective frame, door sets, levers jacket, spoiler . 2, glazing glass doors and windows can be used as PC, PC laminates are widely used in protective window banks, embassies, detention centers and public places for aircraft cabin enclosures, lighting equipment, industrial safety shields and bulletproof glass. 3, PC board can do all kinds of signs, all kinds of signs, such as automotive pump dial, automotive dashboards, warehouses and outdoor commercial signs, point sliding indicator. 4, electrical and electronic PC to be used as junction boxes, sockets, plugs and bushings, gaskets, television conversion device, a phone line connection communication cable bracket, the breaker box, telephone switchboard, switchboard components, the relay case. 5, industrial machinery parts and tools power tool handles, internal gears, turbines, bushings, guide, refrigerator shelves, appliance parts, the body diode products, all kinds of parts. 6, appliances PC to do low-load parts, motors used in household appliances, vacuum cleaners, shampoo, coffee maker, toaster. 7, the optical disc is ideal for PC disc storage medium materials. 8, bottles and containers PC bottle (container) transparent, light weight, impact resistance and good resistance to heat and corrosion certain washing solution as recyclable bottle (container) 9, computer PC and PC alloy can be used as a computer rack, housing and auxiliary equipment, printer parts. 10, medical and health care Modified PC-resistant high-energy radiation sterilization, resistant to cooking and baking disinfection apparatus for blood samples, blood oxygenator, surgical instruments shell, kidney dialysis and so on. 11, leisure and PC can be used as protective equipment helmets and helmets, protective masks, sunglasses and sports goggles. 12, the film is widely used in printing charts PC film, medical packaging, film converter. IV molding 1, PC injection molding and injection molding conditions of PC mainly used to produce more sophisticated, withstand greater impact loads, the small products. PC is easy to absorb water, and the water temperature molding process also allows PC hydrolysis and degradation, seriously affect the quality and appearance of physical and mechanical properties of products, thereby controlling the moisture content is one of the key product quality assurance. Injection molding: Injection reference conditions treated material is dried → → products suitable for industrial condition of the PC: 270 to 300 injection pressure technology values ??of process parameters values ??the front cylinder temperature ° C / Mpa 6 ~ 14 270 ~ 300 Central screw Speed ??/ (r / min) 30 ~ 120 240 ~ 280 rear screw back pressure of 0 to 10 nozzle temperature / ° C 270 ~ 300 molding cycle / S 1 ~ 25 Injection Mold Temperature / ° C 70 ~ 100 5 ~ 402 cooling , PC PC extrusion extrusion molding material for the manufacture of PC molecular weight plates, tubes, rods and other shapes as well as film, the use of the higher, generally in the 4 th power of more than 3.4 × 10. PC pipe extrusion process conditions: conditions conditions glass fiber reinforced PC PC PC PC glass fiber reinforced rear cylinder temperature ° C outside diameter of the mandrel 250 240 / mm 26 26 255 250 aspect ratio of the front of the head temperature 2424 230 220 ° C rear pipe inner diameter / mm 25.5 25.8 220 215 front of the pipe diameter / mm 32.8 32.9 die temperature ° C 210 225 vacuum sizing inner diameter / mm 33 33 Screw speed / (r / min) 10.5 10.5 set diameter with the die gap 2020 die housing inner diameter / mm 33 26 cooling water temperature / ° C 80 80 3, PC blow molding method for blow molding PC can be produced packaging container (bottle), including extrusion blow molding, extrusion blow molding and injection blow molding, blow molding Either, should the material prior to molding strict drying, the water content is as low as 0.01% PC process Process parameter values Parameter Value cylinder temperature - - die adapter temperature ° C 260 ~ 270 260 ~ 270 front head temperature ° C 250 ~ 270 250 ~ 270 central die temperature ° C 255 ~ 270 240 ~ 270 rear Mold temperature ° C 50 ~ 90 Notes: 1, injection pressure, the tube temperature is too high or long residence time, can lead to thermal decomposition, discoloration and reduce property, must pay attention to the mold temperature to 85 ° C ~ 120 ° C prevail. (1) at 0.02% moisture control; (2) to 120 ° C dry 4 hours, Do not exceed 150 ° C 2, thick molding finished especially difficult, because the finished product prone to residual stress, can cause rupture of the future, and therefore should be powdered silicon AstraZeneca as release agent, do not use liquid release agent. 3, high temperature and pressure molding to be required to use a screw-type molding shuttle. 4, the material to be dried thoroughly before use. 5, the gate channel design should have a smaller flow impedance. 6, moldings proximity of the flesh should be designed to avoid any metal inlays. Furthermore, the withdrawal shall be tilted 2 ° or more. 7, mold shrinkage of 0.4% to 0.7%, the proportion of 1.2 to 1.5.