Since PET macromolecules contain fat bases and have certain hydrophilicity, pellets are more sensitive to water at high temperatures. When the moisture content exceeds the limit, the molecular weight of PET Honey Bottles will decrease during processing, and the products will become colored and brittle.

Therefore, the materials must be dried before processing, and 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. Generally, the proportion of recycled PET preforms should not exceed 25%, and the recycled materials should be thoroughly dried. Since PET has a short stable time after the melting point and high melting point, it is necessary to choose an injection system with more temperature control sections and less self-friction heat generation during plasticization, and the actual weight of the product (water cut material) cannot be less than the machine injection 2/3 of the amount. PET preforms are generally formed by hot runner molds. It is better to have a heat shield between the mold and the injection molding machine template, the thickness of which is about 12mm, and the heat shield must be able to withstand high pressure. The exhaust must be sufficient to avoid local overheating or chipping, but the depth of the exhaust port should generally not exceed 0.03mm, otherwise it is easy to produce flash.

Generally, do not use too long residence time for injection molding 100ml Plastic Spray Bottle to prevent molecular weight drop, and try to avoid temperatures above 300°C. If the machine is shut down for less than 15 minutes, only air injection is required; if it takes longer than 15 minutes, it must be cleaned with viscosity PE, and the barrel temperature should be lowered to the PE temperature until the machine is turned on again.