The injection molding technology of TPE plastic raw materials is based on the characteristics of the materials and the supply situation. Usually, the appearance and technical performance of the materials should be checked before molding. The supplied granular materials are usually rich in varying degrees of moisture, fluxes, and other volatile low molecular substances, especially TPE with a hygroscopic tendency, whose moisture content always exceeds the processing limit allowed. Therefore, it is necessary to perform drying treatment and determine the moisture content before processing.

At high temperatures, the moisture content of TPE is required to be below 5%, or even 2% to 3%, so vacuum drying boxes are commonly used to dry at 75 ℃ to 90 ℃ for 2 hours. It is necessary to properly seal and retain dry materials to prevent them from losing their drying effect due to moisture absorption from the air. Therefore, selecting a drying chamber hopper can continuously supply dry hot materials to the injection molding machine, which is beneficial for simplifying work, maintaining cleanliness, improving quality, and adding injection rates. Generally speaking, the viscosity of the color masterbatch should be lower than that of TPE, because TPE has a higher melt index than the color masterbatch, which will facilitate the dispersion process and make the color dispersion more uniform. The loading amount of the dry hopper is usually 2.5 times the hourly material consumption of the injection molding machine. TPE based on SBC outperforms most other TPE materials in terms of color. So, they only require a small amount of color masterbatch to achieve a specific color effect, and the colors produced are more pure than other TPEs.

Precautions for TPE plastic injection molding:

1. Completely clean the material barrel
2. Ensure outstanding dryness
3. Typical temperature settings
4. Injection molding speed setting
5. Maintaining pressure setting
6. Secondary injection molding request
Regarding TPE based on harder SEBS, it is recommended to use polypropylene as a color carrier.
For TPE based on softer SEBS, low-density polyethylene or ethylene vinyl acetate copolymer can be selected.
Regarding softer types, it is not recommended to use PP color carriers as the hardness of the composite material will be affected.
Regarding the use of certain encapsulation injection molding, the use of polyethylene color carriers may have a negative impact on the adhesion with the substrate.

Article organization sealing glue manufacturer www.hshangli.com