PE is the world's largest production of synthetic resin and the largest consumption of plastic packaging materials. Polyethylene products are divided into three types: low density, medium density and high density. Among them, high-density polyethylene (HDPE) has a high degree of crystallinity, and its hardness, air tightness, mechanical strength, and chemical resistance are good, so it is widely used in blow molding to make bottles and other hollow containers. Utilizing the good characteristics of PE heat-sealing performance, containers made of various composite materials, cosmetic pump head manufacturers, can hold various beverages such as lemon juice and fruit juice.
The production process of pump head material PET
PET has better rheology in the molten state, and the pressure has a greater effect on viscosity than temperature. Therefore, the pressure is mainly used to change the fluidity of the melt. 1. Treatment of plastics. Because PET macromolecules contain fat bases and have a certain degree of hydrophilicity, pellets are more sensitive to water at high temperatures. When the moisture content exceeds the limit, the molecular weight of PET will decrease during processing, and the products will become colored, Become brittle.
Therefore, the materials must be dried before processing. The drying temperature is 150°C for more than 4 hours, generally 170°C for 3-4 hours. The air shot method can be used to check whether the material is completely dry. The proportion of recycled materials should generally not exceed 25%, and the recycled materials must be thoroughly dried.