The following methods can be used to solve the problem of opaque preforms in the preform injection molding process:
1. Adjust the parameters of the injection molding machine:
The parameters of the injection molding machine system, such as the raw material heating temperature, screw heating temperature, injection pressure and speed etc, have a direct impact on the transparency of the preform.By adjusting the injection molding process parameters, the crystallinity and transparency of the preforms in production can be changed. Specific methods include appropriately increasing the material temperature, speeding up the injection speed, reducing the holding pressure, etc.
2. Ensure the quality of raw materials:
The moisture content of the raw materials, the degree of plasticization of the screw, and the quality and cleanliness of the secondary recycled materials will affect the transparency of the preform. Therefore, the drying time of the raw materials should be ensured to be more than 4 hours, the material temperature should be increased, the moisture content of the raw materials should be controlled to improve the degree of plasticization, and the purity of the raw materials should be checked.
3. Adding additives:
During the injection molding process, an appropriate amount of additives can be added to improve the transparency and gloss of the product. However, it is necessary to add according to the guidance and proportion to avoid adverse effects on other properties of the preform.
In summary, solving the problem of opaque preforms in the preform injection molding process requires comprehensive consideration of multiple factors, including injection molding machine parameters, raw material quality, additives, etc. By adjusting and optimizing these aspects, the transparency and quality of the preforms can be effectively improved.