Polycarbonate Injection Molding: Overview of Custom Services
Polycarbonate Injection Molding
Details
Details:
Model
Material
Brand
Origin
Application
Booling-Injection-8
P20, 718, S136, 2738 etc
Booling
China
Automotive parts, industrial parts, medical parts, household
Polycarbonate custom injection molding technology is widely used in the automotive industry, electronic and electrical assembly, and glass assembly fields. In addition, there are also some industrial parts, packaging, film and other applications that can provide flexible customization services.
Advantages of Polycarbonate Injection Molding：
- High impact strength
- High transparency
- Good flame retardant performance
- Environmentally friendly and harmless
- Low shrinkage rate
Related Hot Products
Polycarbonate injection molding material is a noncrystalline thermoplastic with excellent optical and physical properties and accounts for a large proportion of plastic injection molding processes.
Polycarbonate materials gradually become transparent glassy substances during the plasticization and melting process. Their injection molding products have outstanding characteristics such as low creep, stable size, fatigue resistance, and impact resistance.
Characteristics of Polycarbonate Injection Molding
Polycarbonate injection molding materials have good transparency and free dyeing properties, and can effectively resist the corrosion of chemical substances such as acids, alkalis, and salts.
-Process Conditions for Polycarbonate Injection Molding:
- Drying Treatment before Raw Material Processing: Polycarbonate (PC) material has a certain degree of moisture absorption, so the key step before injection molding is to dry it. In general, the recommended drying temperature for suppliers is 100 ℃~200 ℃, and the time should be within 3-4 hours. The humidity and moisture content of polycarbonate materials must be less than 0.02% to enter the formal injection molding process.
- Melting Temperature: 260~340 ℃
- Mold Temperature: 70~120 ℃
- Injection Pressure: Use high injection pressure as much as possible under actual conditions to improve injection efficiency.
- Injectioned: When the sprue is small, low-speed injection can be used, but for other types Speof sprues, high-speed injection can be used as much as possible.
-Chemical and Physical Properties:
Polycarbonate (PC) is an amorphous engineering material with particularly good impact strength, flame retardant properties, glossiness, thermal stability, bacterial inhibition properties, and pollution resistance. In addition, polycarbonate has very high impact strength and low shrinkage rate, generally ranging from 0.1% to 0.2%. This characteristic is beneficial for maintaining the consistency of the final product and reducing the probability of defects. Polycarbonate has strong physical and mechanical properties, but poor flow characteristics and high viscosity, making the injection molding process of this material difficult and requiring multiple processing methods. Manufacturers need to consider the intended use of the final product and customer requirements when deciding on the quality of polycarbonate raw materials to choose from. If the final product has high impact resistance and mechanical properties, manufacturers can use low-flow rate PC materials; On the contrary, high-flow rate polycarbonate materials can be used, which can not only optimize the injection molding process but also save costs and obtain more suitable parts.
Polycarbonate Injection Molding Process
In the polycarbonate injection molding process, the injection molding machine heats the raw materials to a certain temperature and high-pressure injects the melted liquid material into a closed mold cavity. After cooling and shaping, the desired product is ejected after opening the mold.
- Pre-treatment of Plastics
Polycarbonate materials have a high water absorption rate and often have a high moisture content before being put into use. Therefore, manufacturers must preheat and dry them before injection molding. The drying temperature of high-purity polycarbonate is about 120 ℃, while modified PC materials generally need to be dried at 110 ℃ for at least 4 hours. Except for some special circumstances, the drying time of raw materials cannot exceed 10 hours. In general, manufacturers can determine whether the drying time is sufficient and whether the moisture content meets the requirements for processing by using the air extrusion method. Polycarbonate can be mixed with recycled materials during processing, and the proportion of recycled materials used can reach 20%. Even in some cases, all materials used may be recycled materials, but the actual proportion of recycled materials used still needs to be considered based on the quality and performance requirements of the product. In addition, if recycled materials are selected for mixing in the production process of polycarbonate, different color masterbatch cannot be mixed simultaneously, otherwise it will seriously damage the properties of the finished product.
- Selection of Injection Molding Machines
Due to cost and material properties, modified materials have gradually become a common choice for manufacturers in modern polycarbonate injection molded products. Especially when injection molding some electrical products, it is necessary to increase the performance of fire and moisture prevention. When injection molding flame-retardant polycarbonate and other plastic alloy products, manufacturers require the plasticizing system of the injection molding machine to have good mixing function and corrosion resistance. This is difficult to achieve with conventional plasticizing screws, and manufacturers must pay attention to this when selecting.
- Mold and Sprue Design
The common mold temperature for polycarbonate injection molding is 80 ℃ -100 ℃, and for adding fiberglass it is 100 ℃ -130 ℃. For small products, needle-shaped gates can be used, and the gate depth should reach 70% of the thickest part of the part. In addition, other gates have circular and rectangular shapes. The larger the sprue, the better. A larger sprue can reduce defects caused by excessive cutting of plastic. In addition, the depth of the exhaust hole of the mold should be less than 0.03-0.06mm, and the flow channel should be as short and round as possible. The demolding slope is generally around 30 °~1 °.
- Melt Glue Temperature
The processing temperature can be determined using the air injection method. The temperature for general polycarbonate injection molding processing is 270 ℃~320 ℃, and for some modified or low molecular weight PCs it is 230 ℃~270 ℃.
- Back Tressure
Polycarbonate injection molding can be adjusted to a back pressure of around 10 bar, which can be appropriately reduced according to specific situations without air pockets or color mixing.
- Retention Time
Prolonged retention of polycarbonate in high-temperature environments can cause the material to deteriorate, turn yellow, and release a certain amount of carbon dioxide. At this point, the manufacturer will choose to use PS material to clean the barrel.
- Precautions
Some modified PCs, due to excessive recycling, may result in uneven mixing of various components or a decrease in molecular weight, which can easily produce dark brown liquid bubbles and affect subsequent production performance and appearance.
Application of Polycarbonate Injection Molding
Polycarbonate injection molding has excellent optical and physical properties, making it applicable in various fields.
- Automotive Manufacturing Industry
Polycarbonate injection molded products have good impact resistance and heat distortion resistance, can adapt to a high-temperature range, and have good weather resistance and high hardness. Therefore, car and light truck manufacturers will choose this manufacturing method, which mainly focuses on instrument panels, lighting systems, heating plates, defrosters, and polycarbonate alloy bumpers.
- Optical Lenses
Polycarbonate injection molding materials have become an ideal material choice in the field of optical lenses due to their unique characteristics of high refractive index, high transmittance, dimensional stability, high impact resistance, and easy processing and molding. Optical lenses made of optical grade polycarbonate can be used not only for the production of various precision instruments such as microscopes, cameras, telescopes, and optical testing instruments but also for film projector lenses, infrared autofocus projector lenses, copier lenses, laser beam printer lenses, as well as various office equipment and home appliances such as prisms and multi-faceted mirrors. Their application market in optical lenses is extremely broad.
- Building Materials Industry
Polycarbonate sheet has good transparency and impact resistance, UV radiation resistance, dimensional stability of its products, and good injection molding processing performance, making it have significant technical performance advantages over traditional inorganic glass used in the construction industry, and can be better applied in the building materials industry.
- Aviation and Aerospace
With the rapid development of aviation and aerospace technology, the requirements of modern science and technology for various components in aircraft and spacecraft are constantly increasing, and the application of polycarbonate injection molding in this field is also increasing. According to incomplete statistics, there are as many as 2500 polycarbonate components used on just one Boeing aircraft. On the spacecraft, hundreds of different configurations of polycarbonate components reinforced with glass fibers and protective equipment for astronauts are used.
- Electronic Appliances
Due to its ability to adapt to a wide range of temperature and humidity, polycarbonate injection molding technology has good and constant electrical insulation properties, making it an excellent insulation material. The nonflammability and electrical insulation properties of its materials make it an ideal choice for the electronics and electrical industry. Polycarbonate resin is mainly used for injection molding production of various food processing machinery, machine bodies, power tool casings, brackets, vacuum cleaner parts, and refrigerator freezer drawers. For important components in video recorders, computers, and color televisions that require high precision, polycarbonate injection molding technology has also shown extremely high practical value.
- Medical Devices
Due to the high-temperature resistance of polycarbonate injection molded products, they can maintain stable performance in high-temperature environments, withstand cleaning agents, steam, heating, and high-dose radiation disinfection, and their physical properties will not decrease or turn yellow, which will affect their performance. Therefore, they are widely used in artificial kidney hemodialysis equipment and other medical devices that require transparent and intuitive operation and repeated disinfection. Such as producing disposable dental appliances, high-pressure syringes, blood separators, surgical masks, etc.
Related News
Applied’s expertise in modifying materials at atomic levels and on an ihdustrial scaleenables our customers to transform possibilities into reality.
