Name | Polycarbonate |
Synonyms | PC Polycarbonate Polycarbonate,colored Polycarbonate, flame retarding POLYCARBONATE STANDARD 326, FOR GPC POLYCARBONATE STANDARD 6'800, FOR GPC POLYCARBONATE STANDARD 3'860 FOR GPC POLYCARBONATE STANDARD 50'000 FOR GPC POLYCARBONATE STANDARD 30'600, FOR GPC POLYCARBONATE RESIN, SECONDARY STANDARD POLY(BISPHENOL A CARBONATE), MELT INDEX 7 2,2-Bis(4-hydroxyphenyl)propyl polycarbonate 4-[1-(4-hydroxyphenyl)-1-methyl-ethyl]phenol carbonate POLYCARBONATE RESIN, SECONDARY STANDARD, MOLECULAR WEIGHT SERIES |
CAS | 25037-45-0 |
InChI | InChI=1/2C15H16O2.CH2O3/c2*1-15(2,11-3-7-13(16)8-4-11)12-5-9-14(17)10-6-12;2-1(3)4/h2*3-10,16-17H,1-2H3;(H2,2,3,4)/p-2 |
Molecular Formula | C16H18O5 |
Molar Mass | 290.32 |
Density | 1.2g/mLat 25°C(lit.) |
Melting Point | 220~230℃ |
Boling Point | 784.3°C at 760 mmHg |
Flash Point | 442°C |
Solubility | chlorinated solvents: soluble |
Vapor Presure | 6.56E-26mmHg at 25°C |
Appearance | neat |
Storage Condition | Room Temprature |
Refractive Index | n20/D 1.586 |
Physical and Chemical Properties | Characteristics of non-toxic, odorless, colorless to light yellow transparent solid. melting point 220~230 ℃ (crystal) relative density 1.2 soluble in dichloromethane and p-dioxane, slightly soluble in aromatic hydrocarbons and ketones. |
Use | Used for electronic and electrical parts, machinery and textile industry parts, building structures, aviation transparent materials and components, foam structure materials |
WGK Germany | 3 |
polycarbonate is an amorphous, tasteless, odorless, non-toxic transparent thermoplastic polymer, with excellent mechanical, thermal and electrical properties, especially impact resistance, good toughness, small creep, product Size is stable. The notched impact strength was 44kj/mz and the tensile strength was> 60MPa. Polycarbonate has good heat resistance and can be used for a long time at -60~120 ℃. The heat distortion temperature is 130~140 ℃, the glass transition temperature is 145~150 ℃, and there is no obvious melting point, in the molten state at 220~230. Thermal decomposition temperature> 310 °c. Due to the rigidity of the molecular chain, its melt viscosity is much higher than that of general purpose thermoplastics. Polycarbonate has excellent electrical properties, and its volume resistivity and dielectric constant are equivalent to those of polyester film, which are 5 × 1013 Q, respectively. m and 2.9(106Hz), dielectric loss tangent (106Hz)<1.O× 10 -2, second only to polyethylene and polystyrene, and almost unaffected by temperature, close to a constant in the range of 10 to 130 ° C., it is suitable to produce an electronic component that operates at a higher temperature. Polycarbonate light transmittance is good, the light transmittance is 85% ~ 90%. In the chemical resistance, the dilute acid, oxidant, reducing agent, salt, oil, aliphatic hydrocarbon stability, but not alkali, Amine, ketone, aromatic hydrocarbon and other media, soluble in dichloromethane, dichloroethane and other chlorinated hydrocarbons. The product is easy to produce stress cracking, especially the long-term immersion in boiling water is easy to cause hydrolysis and cracking. In addition, polycarbonate has a low water absorption rate of 0. 16%, excellent weather resistance, good colorability, and flame resistance in accordance with the standards of UL Specification 94 Vl and 94 V-2, and is a self-extinguishing resin.
There are two methods of industrial production.
It can be used as an insulating connector, a coil frame, a terminal, a gasket, and the like for electronic computers, televisions, radios, sound box devices, and household appliances in the electronic and electrical appliance industry. It may also be used as an electrical tool housing such as a hand drill housing, a telecommunications equipment housing, and the like. In the machinery industry suitable for the transmission of small and medium load parts such as gear, rack, Cam, worm and so on. Used as a small force of fasteners such as screws, nuts, etc. in place of metal parts. In terms of safety and medical treatment can be used as a safety helmet, Aerospace cap, explosion-proof glass, protective glasses, can be made to high temperature Disinfection medical surgical vessels. In aviation, transportation and optical machinery can be used for aircraft, train, automobile, ship windshield, seat window cover, lamp cover, sunglasses glass, optical disc, camera optical and mechanical components. In construction and agriculture, a large number of high impact strength of the window glass and glass greenhouse, with high safety and decorative. In the textile industry can produce a variety of weft tube, tube, wool tube, hemp tube. In addition, Polycarbonate may also be used as a foam construction material.
resin production raw materials, the skin and mucous membranes of the human body have different degrees of stimulation, can cause skin allergic reactions and inflammation; At the same time also pay attention to the harm of resin dust on the human body, long-term inhalation of high concentrations of resin dust, can cause lung lesions. Most of the resin has a common hazard characteristics: open flame, high temperature flammable, and oxidant exposure will cause combustion risk, therefore, the operator to improve the operating environment, the operating area and the non-operating area shall be intentionally drawn apart, automated and closed as far as possible, and ventilation facilities shall be installed. This product is external polypropylene and other plastic woven bags, lined with plastic bags (such as polyethylene bags) packaging, each 25kg. Storage and Transportation to prevent heat, moisture, to avoid the erosion of organic solvents and alkaline materials, should not be exposed to outdoor for a long time.
can be extrusion, injection molding, blow molding and vacuum molding method for processing, manufacturing a variety of tubes, plates, containers, parts and films, etc., of which the most commonly used is the injection molding method. In the process of processing at 300 ℃, trace water can cause hydrolysis of polycarbonate and reduce the performance, so the material must be strictly dried before processing, so that the moisture content of the resin is controlled to be less than 0. 03%. It is generally continuously dried in a forced air oven at 110 ° C. For 10 to 12 hours; If a vacuum oven is used, it can be reduced to 6 to 8 hours. The thickness of the material layer should not exceed 20mm. In the injection molding, the screw injection molding machine is more uniform than the plunger injection molding machine, the processing temperature is slightly lower, and the thermal degradation phenomenon is less. Generally, higher cylinder temperature and higher injection pressure are used, and the internal stress generated in the molding process is reduced by increasing the mold temperature. Generally, the temperature range of the cylinder is 220 to 250 ° C. In the rear section; 230 to 270 ° C. In the middle section; And 240 to 290 ° C. In the front section. The injection pressure was 39.2~127 MPA. The mold temperature is controlled at 80 to 120 degrees C. When the insert is processed, the metal insert needs to be heated to more than 120 degrees C, and the insert with a diameter of 1 to 2mm does not need to be heated. The polycarbonate thickness of the coated insert shall be equal to the diameter of the insert for the iron insert, 0.9 times the diameter for the brass, and 0.8 times for the aluminum, the injection molding cycle depends on the product thickness, from tens of seconds to minutes. Most of the polycarbonate injection molded products have internal stress, therefore, the products need to be in the oil bath of 110 N130 ℃, hot air oven or infrared incubator for heat treatment, the treatment time depends on the thickness of the product.
EPA chemical information | Information provided by: ofmpub.epa.gov (external link) |
application | polycarbonate film can be used to make capacitors, audio tapes, color video tapes, solar energy utilization devices, microwave heating systems, anti-dialysis membranes, and over-filter membranes; Its foam plastic has flame resistance and thermal insulation, and is used in the construction industry. However, polycarbonate has low fatigue strength and is prone to stress cracking. Glass fiber reinforcement is commonly used to avoid the above shortcomings and improve many other properties. If it is blended with a variety of polymers, or added with various stabilizers, flame retardants, antistatic agents, new varieties can be made to expand its application range. |
polymer compound | polycarbonate is a general term for polymer compounds containing carbonate in the molecular backbone. There are many types, and the most practical value is bisphenol A polycarbonate. Non-toxic, odorless, colorless to pale yellow transparent solid. In 1953 H. Schnell and others produced thermoplastic high melting point polycarbonate in Bayer, Germany. In 1958 and 1959, Bayer of Germany and General Electric of the United States successively realized industrial production. By the 2070s, the production scale quickly reached 10,000 tons. At present, the more advanced and widely used method is the interfacial polycondensation process of bisphenol A sodium salt and phosgene reaction. polycarbonate has developed many modified varieties through copolymerization, blending and reinforcement. Glass fiber reinforced polycarbonate has more outstanding rigidity, dimensional stability and creep resistance. The strength and elastic modulus are increased by 2-3 times, the hardness is increased by 20%-30%, and the thermal expansion coefficient is reduced to the original 1/3. Polycarbonate is one of the most important engineering plastics. It has excellent properties such as toughness and rigidity, stable size, easy coloring, transparency, good electrical insulation, corona resistance, and stability to ozone. It can withstand turning, milling, planing, grinding, sawing, drilling, stamping and other mechanical processing, so it is widely used in various sectors of the national economy, instead of copper, aluminum, zinc and other non-metallic materials such as non-ferrous metals and glass, wood and other non-metallic materials, it is used to manufacture windshields and driving windows of aircraft and vehicles, as glass for vehicles and houses, and to make lighting fixtures, explosion-proof fixtures and safety masks. It is used to manufacture various mechanical parts (such as gears, screws, crankshafts, guide rails, valves, pipe fittings, etc.), plastic optical fibers, communication appliances and various glasses lenses. Polycarbonate can also be used to manufacture housings and parts of various electrical equipment and appliances. Because it is non-toxic, tasteless and heat-resistant, it can make various medical appliances, surgical instruments, dental implants, kitchen utensils, beverage containers, food utensils, water filters, etc. Polycarbonate film can be made of capacitors, audio tapes, color video tapes, solar energy utilization devices, microwave heating systems, anti-dialysis membranes, and over-filter membranes; its foam plastic has flame resistance and thermal insulation, and is used in the construction industry. However, polycarbonate has low fatigue strength and is prone to stress cracking. Glass fiber reinforcement is commonly used to avoid the above shortcomings and improve many other properties. If polycarbonate is blended with various polymers, or various stabilizers, flame retardants, and antistatic agents are added, new varieties can be made to expand its application range. |
glass fiber reinforced polycarbonate | the strength and elastic modulus of glass fiber reinforced polycarbonate are much higher than those of pure polycarbonate, and the thermal deformation temperature is also increased to a certain extent, which overcomes the disadvantages of unresistant stress cracking and low fatigue strength of pure polycarbonate, but the impact strength decreases. With the increase of glass fiber content, the strength also increases accordingly. the glass fiber reinforced polycarbonate produced by Bayer company in Germany has been used in electronics, electromechanical, aviation, communication, instrumentation and other industries as patch boards, connectors, gears, turbines, junction boxes, lighting lamp holders, coil skeletons, household appliance parts, heat-resistant precision parts, brush holders, dust plates, collector rings, wiring switches, hand electric drill parts, insulation blocks, solenoid valve housings, hand wheels, handles, valve bodies, etc. |
medical polycarbonate | medical polycarbonate refers to medical polymer materials containing carbonate in the molecular backbone. It is characterized by high impact strength, light weight, slow hydrolysis in alkaline solution and aqueous medium, and degradable in biological environment. Used as bone substitute material and dental material; block copolymer made with polyether is used as dialysis membrane of artificial kidney; copolymer with dimethylsiloxane can be used as oxygenator membrane. In order to improve the biodegradation performance, functional subunits such as methyl and hydroxyl can be introduced. |
properties and uses | polycarbonate is an engineering plastic with excellent properties. Its main properties are as follows: (1) Polycarbonate is an amorphous, odorless, non-toxic, transparent thermoplastic. Generally, the light transmittance is 85% ~ 90%, which can be made into nearly colorless and transparent products with good coloring. (2) the most important mechanical properties of polycarbonate are toughness and rigidity, the impact strength without notch reaches 4.5MPa, the tensile and bending strength is similar to nylon and polyoxymethylene, and it is among the best in thermoplastics, close to the level of glass fiber reinforced phenolic or unsaturated polyester, showing ductile fracture. The molded parts can achieve very precise tolerances and maintain dimensional stability in a wide range of changes. The molding shrinkage is constant at 0.5 ~ 0.7%. It also has outstanding creep resistance, and its tensile, bending, and compression strength is equivalent to that of polyester glass fiber reinforced plastic and nylon 66, but its elongation at break is much smaller than that of nylon. It has a high elastic modulus, and its elastic modulus is very sensitive to temperature below 100 ℃. (3) polycarbonate has good heat resistance and can be used for a long time at -60~120 ℃. the thermal deformation temperature is 130~140 ℃, the glass transition temperature is 149 ℃, there is no obvious melting point, it is in a molten state at 220~230 ℃, and the thermal decomposition temperature is> 310 ℃. It is a self-extinguishing resin. (4) low water absorption, 0.16%, small molding shrinkage, 0.5% ~ 0.6%, uniform shrinkage, stable size, can manufacture precision parts. (5) It has good and constant electrical insulation and corona resistance in a wide temperature range and under humid conditions. Medium arc resistance. (6) It has good chemical resistance and atmospheric aging resistance, can resist the drastic changes of sunlight, water and temperature, and is stable to water, acid, etc., but it is not resistant to alkali, ketone and other media, soluble in chlorinated hydrocarbons, Long-term immersion in boiling water, easy to cause hydrolysis and cracking. its shortcomings are low fatigue strength, poor stress cracking resistance, sensitive to gaps, and easy to produce stress cracking. Polycarbonate has a wide range of uses and can be used as mechanical parts, such as gears, car housings, etc. And because it is non-toxic, it can be used as food packaging and tableware. The tea set made from it comes into contact with tea and coffee and will not fade or stain, nor will it affect the original color and taste of the food. |
preparation of polycarbonate by transesterification | preparation of polycarbonate by transesterification bisphenol A and diphenyl carbonate in the presence of catalyst (such as sodium tetraphenylborate) and nitrogen, transesterification at high temperature (160~250 ℃) under reduced pressure, and then polycondensation and granulation at 250~300 ℃ to obtain the final product. reaction formula for polycarbonate production by transesterification method: the process flow of transesterification method is: the advantages of transesterification method are that the raw material diphenyl carbonate is easy to prepare, the purity is high, the product does not need post-treatment, and it can be directly granulated and packaged after discharging. The disadvantage is that high temperature and high vacuum are required, special stirring device is required, and high molecular weight polymer is not available. |
preparation by phosgene method | preparation by phosgene method polycarbonate phosgene method bisphenol A, sodium hydroxide, catalyst and molecular weight regulator carry out phosgene gasification and polycondensation reaction at normal temperature and normal pressure, remove the upper alkali salt solution of reactant, neutralize with formic acid to slightly acidic, remove the upper acid water, and wash until it does not contain chloride ions, the resin is precipitated in powder form by precipitation agent, and then heat stabilizers are added, and the finished polycarbonate is obtained by extrusion and granulation. reaction formula for producing polycarbonate by phosgenation method: the process flow of phosgenation method is: the advantages of phosgenation method are that it is carried out at normal temperature and pressure, the equipment is simple, and high molecular weight polymer (molecular weight 3~100,000) can be obtained; The disadvantage is that phosgene is highly toxic and requires special protection, the product needs post-treatment and granulation, the solvent needs to be recovered, and the process flow is complicated. |
use | used to make shirts, bedding, table cloths, work clothes, etc. used for optical disc substrate materials. Used as electronic and electrical parts, mechanical and textile industrial parts, building structural parts, aviation transparent materials and parts, foam structural materials, etc. |
production method | there are two methods for the synthesis of polycarbonate, one is phosgene method and the other is transesterification. Phosgene method: Phosgene method is also called solvent method and interfacial polycondensation method. It is a polycarbonate prepared by interfacial polycondensation of bisphenol A sodium salt and phosgene under normal temperature and pressure. The phosgene production process is mainly divided into the following steps: photogasification. The prepared bisphenol sodium salt is added to the phosgenation kettle, and then dichloromethane is added to the phosgenation kettle, and the stirring is started. When the temperature in the kettle drops to 20 ℃, phosgene is introduced at a constant speed for phosgenation reaction. When the pH value of the reaction medium is 7-8, the phosgene is stopped and the phosgene reaction is over. Polycondensation. The phosgenate, 25% lye, catalyst, trimethylbenzylammonium chloride and molecular weight regulator phenol are added into the reaction kettle, and the reaction is continued at 25-30 ℃ for 3-4h under stirring. The reaction is exothermic and cold water should be used for cooling. When the reaction is terminated, the upper alkali salt solution is removed by standing and stratified layer, and then 5% formic acid is added to neutralize until the material is slightly acidic, the upper acid water phase is separated, and the reaction solution is post-treated after neutralization. Post-processing. The post-treatment is to remove the salt in the resin on the one hand, and the low molecular weight and unreacted bisphenol A in the resin on the other. The removal of salt is generally washed by water, that is, the neutralized resin solution is stirred with water to wash off the salt in the resin until the washing water does not contain chloride ions. Low molecular substances generally use precipitation method. That is, the resin solution after washing is added with a precipitant to precipitate polycarbonate in powder or granule. The precipitant can use alcohols, ketones and petroleum ethers, toluene or xylene. The conversion efficiency of phosgene method is high, generally above 90%, and the relative molecular mass can be as high as (15-20)× 104, but the molecular mass is too high, making it difficult to form. Therefore, molecular mass regulators are commonly used to control the molecular weight below 104. Transesterification method: Transesterification method is also called melt polycondensation method. No solvent is used during polymerization, and no solvent recovery equipment is required. The product can be directly discharged and granulated, but the reaction time is longer, and it needs to be carried out under high vacuum and high temperature. Due to the high viscosity of the reaction material, it is difficult to heat exchange and uniformly mix the materials during the reaction, and it is difficult to produce high molecular weight products. The transesterification method was carried out with bisphenol A and diphenyl carbonate in the presence of a basic catalyst under high temperature and high vacuum and melting conditions. Taking bisphenol A: diphenyl carbonate = 1:(1.05-1.1), the reaction temperature is high and the transesterification reaction speed is fast, but bisphenol A is prone to decomposition over 180 ℃, so the upper temperature limit can only be 180 ℃ at the initial stage of transesterification reaction. The catalysts for the transesterification reaction include sodium benzoate, lithium acetate, chromium acetate, cobalt acetate and potassium hydride. Its dosage is bisphenol A 0.0025%. The transesterification process has three steps: transesterification: bisphenol A and diphenyl carbonate are added to the transesterification kettle for melting, then catalyst is added, and transesterification is carried out at about 175 ℃ under 6650Pa vacuum for the first stage reaction. When a large amount of phenol in the reaction system is evaporated, the temperature is raised to 200-230 ℃, and the by-product phenol is continuously evaporated under a vacuum of 1330-5320Pa. When the evaporation amount is 80%-90% of the theoretical amount, the transesterification ends. Press the reactants to the polycondensation kettle with chlorine. Polycondensation reaction The reactants after transesterification are under stirring and vacuum (133Pa), and the temperature in the kettle is controlled to be 295-300 ℃ for polycondensation reaction, and phenol and diphenyl carbonate are removed. As the reaction progresses, the melt viscosity of the product increases and the molecular weight increases until the required index. After the post-treatment polycondensation reaction is completed, the melt is heated at 300 ℃ for 2-5h in inert gas, the melt is discharged, the pellets are soaked in 10% hydrochloric acid solution to remove alkali metal ions of the alkaline catalyst, and then washed with ionless water until the pH value is equal to 7, and finally packaged after drying. |