(Polycarbonate)
English name: Polycarbonate
Specific gravity: 1.18-1.20 g/cm3 Molding shrinkage: 0.5-0.8% Molding temperature: 230-320 ° C Drying conditions: 110-120 ° C for 8 hours
Material properties High impact strength. High impact strength, good dimensional stability, colorless and transparent, good coloring, good electric insulation, corrosion resistance, good abrasion resistance, but poor self-lubrication, tendency to stress cracking, easy to hydrolyze at high temperatures, poor compatibility with other resins. Suitable for the production of instrumentation small parts, insulation and transparent parts and impact parts
Molding properties 1. Amorphous material, good thermal stability, wide range of molding temperature, poor fluidity. Moisture absorption is small, but sensitive to water, must be dried. Molding shrinkage is small, easy to melt cracking and stress concentration, so the molding conditions should be strictly controlled, the plastic parts must be annealed.
2. High melting temperature, high viscosity, greater than 200g of plastic parts, it is appropriate to use heated extension nozzle.
3. Cooling speed, mold pouring system to coarse, short for the principle, it is appropriate to set up a cold material well, the gate should be taken as a large, the mold should be heated.
4. Material temperature is too low will cause the lack of material, molded parts have no luster, material temperature is too high is easy to overflow edge, molded parts blistering. Mold temperature is low shrinkage, elongation, high impact strength, bending, compression, tensile strength is low. Mold temperature exceeds 120 degrees when the plastic parts cooling slow, easy to deformation sticky mold
Polycarbonate is the main chain of molecules containing -[O-R-O-CO]-linked thermoplastic resins, according to the molecular structure of the ester group can be divided into aliphatic, alicyclic, aliphatic and an aromatic type, which is of practical value of the aromatic Polycarbonate, and to bisphenol A polycarbonate for the most important, molecular weight is usually 3-10 million.
Polycarbonate, Polycarbonate, abbreviated as PC. PC is an amorphous, odorless, non-toxic, highly transparent colorless or yellowish thermoplastic engineering plastics, with excellent physical and mechanical properties, especially impact resistance, tensile strength, bending strength, compression strength; creep is small, dimensional stability; good heat resistance and low temperature resistance. In a wide range of temperatures with stable mechanical properties, dimensional stability, electrical properties and flame retardant, can be used for a long time at -60 ~ 120 ℃; no significant melting point, in 220-230 ℃ is molten; due to the rigidity of the molecular chain, the resin melt viscosity; small water absorption, small shrinkage, high dimensional accuracy, good dimensional stability, film permeability is small; is a self-extinguishing material; light stable, but not UV resistance, weathering. Not resistant to ultraviolet light, good weather resistance; oil, acid, not resistant to strong alkalis, oxidizing acids and amines, ketones, soluble in chlorinated hydrocarbons and aromatic solvents, long-term hydrolysis and cracking in the water, the disadvantage is that due to poor fatigue strength, prone to stress cracking, poor solvent resistance, poor abrasion resistance.
PC can be injection molding, extrusion, molding, blow molding, thermoforming, printing, bonding, coating and machining, the most important processing method is injection molding. Before molding must be pre-dried, the moisture content should be less than 0.02%, trace moisture processing at high temperatures will make the products produce a whitish color, silver wire and bubbles, PC at room temperature has a considerable forced high elastic deformation capacity. The impact toughness is high, so it can be cold pressed, cold drawn, cold rolled and other cold molding process. Extrusion with PC molecular weight should be greater than 30,000, to use gradual compression screw, L/D ratio 1:18~24, compression ratio 1:2.5, can be used for extrusion blow molding, injection - blowing, injection - pulling - blowing method of molding high-quality, high-transparent bottles.PC alloys a wide range of types of alloys, to improve the PC melt viscosity (processability) and the products are prone to stress cracking and other defects, PC and different polymers to form alloys or **** blends, to Improve material properties. Specifically PC / ABS alloys, PC / ASA alloys, PC / PBT alloys, PC / PET alloys, PC / PET / elastomer **** blend, PC / MBS **** blend, PC / PTFE alloys, PC / PA alloys, etc., Lee has two material performance advantages, and reduce costs, such as PC / ABS alloys, PC mainly contributes to high heat resistance, better toughness and impact strength, high strength, flame retardant, ABS can improve moldability, apparent quality, reduce density.PC's three major applications are the glass assembly industry, the automotive industry and the electronics, electrical appliances industry, followed by industrial machinery parts, CD-ROMs, packaging, computers, and other office equipment, medical and health care, film, recreation, and protective equipment.PC can be used as glass for windows and doors, and PC laminates are widely used in Protective windows in banks, embassies, detention centers and public **** places, used in aircraft cabin covers, lighting equipment, industrial safety stalls and bulletproof glass. PC boards can be used for various signs, such as gasoline pump dials, automobile instrument panels, cargo and open-air commercial signs, point sliding indicators, PC resin used in automobile camera systems, dashboard systems and interior decorative systems, used as headlamp covers, front and rear automobile gear boards with reinforcing ribbing, reflective mirror frames, door frames, operating rod sheathing, flow blocking boards, PC is used as a junction box, sockets, plugs and bushings, spacers, TV conversion devices, telephone line brackets under the communication cable, PC is applied as a junction box, socket, plug and sleeve, spacer, TV conversion PC is used as junction boxes, sockets, plugs and bushings, gaskets, TV converters, connectors for communication cables under telephone line brackets, electric switch boxes, telephone switchboards, switchboard components, relay housings, PC can be used as low load parts for household appliance motors, vacuum cleaners, shampooers, coffee makers, toasters, handles for power tools, various gears, worm gears, bushings, guide gauges, shelves in refrigerators, etc. PC is an ideal material for optical disc storage media. PC bottles (containers) are lightweight, good impact resistance, resistant to certain high temperatures and corrosive solution washing, as recyclable bottles (containers). pc and pc alloy can be used to make computer racks, shells and auxiliary machines, printer parts. Modified PC is resistant to high-energy radiation sterilization, boiling and baking disinfection, can be used for blood specimen collection instruments, blood oxygenator, surgical instruments, kidney dialyzer, etc. PC can be made into helmets and helmets, protective masks, sunglasses and sports eye protection. PC film is widely used in printing charts, pharmaceutical packaging, membrane commutator.