PEI Injection Molding
PEI is an excellent and stable performanceengineering resins. An outstanding performance PEI resins are able to withstand prolonged high temperature test. This heat-resistant properties, plus excellent flammability and UL certified laboratory that meets the demanding requirements of PEI resins for high temperature applications.
Electronics industry: connectors, general and micro-relay housings, circuit boards, coils, flexible circuits, mirrors, high-precision optical components, high temperature insulation panelsindustry: connectors, high power lamps and lights, control car external temperature sensor compartment, control of air and fuel mixture temperature sensor
Medical field: handle medical surgical instruments, trays, clamps, artificial limbs, medical and dental appliances, light reflectors, product packaging and microwave trays
More, waiting for updating for the application
PEI Injection Molding ductility
PEI resins not only unmatched in both high strength and high modulus properties, it also has outstanding scalability. The yield tensile elongation makes it possible to freely combine a variety of snap-fit design for easy assembly. Even just adding a 10% glass fiber reinforced case, PEI 2100 resin ductility can be maintained within a temperature range of -200 ℃.
PEI Injection Molding Resin Impact strength
PEI 1000 resin having excellent impact resistance practical. Due to the gap sensitivity of PEI molding resin, recommend to comply with the standard design principles. The injection member should minimize the stress concentration points in the application (e.g., sharp corners) in order to provide maximum impact strength. PEI AT * 100 resin dedicated applications require high impact resistance. This series of PEI molding notched Izod impact up to 15km/mз.
More performance for PEI injection molding resin
PEI resins show excellent creep resistance.
PEI molding resin has excellent electrical properties in a wide range of environmental conditions can remain stable. Coupled with the thermal and mechanical properties, so that the resin becomes high requirements PEI ideal forand electrical applications.
PEI 1000 resin in a wide frequency range with very low dissipation factor, especially in the range of kHz (10 * 3-Hz) to gigahertz (10 * 9-Hz) .
(Chemical resistance) Unlike other amorphous resin. PEI polyetherimide resins exhibit a variety of unusual chemicals tenacious corrosion resistance. PEI resin in contact with most of the automotive and aircraft fluids, fully halogenated hydrocarbons, alcohol and dilute aqueous solution showing excellent performance such as retention and environmental stress cracking tolerance. Avoid exposure to hydrogen halide compounds and alkali environments.
(Cleaning and degreasing) PEI injection molding finished parts can be cleaned or degreased with methanol or isopropanol, soap solution, heptane (n) hexane, naphtha. Such components no fully halogenated hydrocarbons or ketones (such as MEK) or base (such as sodium hydroxide) should not be used for cleaning.
PEI injection molding parts design.
In order to maximize the performance of PEI resins, designers should take advantage of excellent physical properties of the PEI material and consider the PEI injection molding process.
Designers should minimize product PEI resin in the molding of internal stress, because the higher the stress in the finished part, more susceptible to chemical corrosion.
Can be used below method minimizes the stress components:
* Avoid the use of thin-walled and sharp corners.
* Avoid dramatic changes in wall thickness.
* Ensure uniform filling parts.
* Without increasing the thickness, suitably design ribs to increase the stiffness.
PEI injection molding mold design
PEI injection molding resin shrinkage.
PEI resins are amorphous materials can be expected to have a good, repeatable shrinkage.
Component design, location and processing conditions will affect shrinkage.
* Reduce the mold temperature can correspondingly reduce mold shrinkage. It should be noted that if the member is injection molded at low mold temperatures (e.g., 38 ℃), was exposed to a temperature higher than the surrounding environment (e.g., 66 ℃) may also be some shrinkage after the injection.
* Increase the injection pressure can reduce mold shrinkage. Not fully populated parts usually have high mold shrinkage.
* Reduce the melting temperature will slightly reduce mold shrinkage.
PEI injection molding
PEI injection molding machine
PEI injection molding resin can be injected on most of standard injection machine. Suggest to use reciprocating screw injection molding machine.
When we determine the size of injection molding machine, we should consider two basic factors total weight of PEI plastic products and total projected area of the injection molded part. Average total injection volume ( all cavities plus runners and gates ) equal to the machine capacity from 30 to 80 percent , then we can have a good injection result. When using the big barre injection machine , if the injection nozzle is too small , it may unnecessarily prolong the residence time of the resin . If necessary at a suitable temperature in the range of injection molding at higher temperatures , reducing the possibility of thermal degradation of the material is usually required to reduce the residence time. Therefore, in order to achieve a higher injection temperature required minimum recommended size of the injection machine should be greater than 60% capacity.
Determining the total projected area of the injection completely ( all withstand the injection pressure with a cavity flow area ) , it should provide 4-6 tons clamping force per square inch of projected area of the work , in order to reduceoverflow . Glass reinforced resin may need slightly higher clamping force ( estimated per square inch to add one ton clamping force ) . Wall thickness, length and injection molding process conditions needed to determine the actual tonnage of clamping force .
Barrel and screw selection of PEI injection molding machine
The diameter of the screw, preferably an aspect ratio of 20:1 so that a compression ratio of 2.2:1. It is also recommended to use short feed zone (paragraph 5) and long compression zone (11), through a constant taper gradually transition to a shorter measurement zone (4). Compression should be a gradual taper at a constant transition is completed, because a sudden change may lead to excessive shear and material degradation. If unable to select a particular screw, having an aspect ratio of 16:1 proved to 24:1 compression ratio of 1.5:1 to 3.0:1 and a general purpose screw is successful. Not recommended to use with vent barrel to process PEI * resin. Check valve should slide backstop ring type. Screw metering area, usually the flow gap of at least 80% of the cross-sectional flow area.
PEI injection molding resin pre-drying.
PEI As with most thermoplastics resins will absorb moisture in the air, which causes degradation of the polymer occurs during injection molding processing. Moisture content exceeds 0.002% may lead to the appearance of a problem,injection molding parts friable and melt flow increase of raw materials, PEI injection molding resin with pre-drying, the moisture content can be achieved generally as recommended.
PEI injection molding temperature
Since PEI injection molding resin has good thermal stability, the melting temperature is used from 338 ℃ to 339 ℃. Typically, most applications to a melting temperature of 357 ℃- 385 ℃. Over 382 ℃ temperatures may cause discoloration, this is because some of the color pigment can not withstand the high processing temperatures. PEI ATX resin grades to be processed at a lower temperature, typically at a temperature in the range of 310 ℃-371 ℃.
PEI injection molding resin always have to be used the thermostat resin mold injection molding. Mold temperature was measured by a surface pyrometer, should be maintained in the range of 107 ℃ to 177 ℃. However, PEI ATX resin grades can be injection molded at a mold temperature below 149 ℃, otherwise there is silver streaks issue. To enhance the performance and extend the life cycle, most PEI injection molding resin component mold had better to have a selection temperature of 93 ℃.
Contact SEASKYTOOLING for the for PEI injection molding now!
You can also sent your inquiry by email directly!