PET bottles have better rheology under melting conditio […]
PET bottles have better rheology under melting conditions, and the effect of pressure on viscosity is greater than temperature. Therefore, the fluidity of the melt is mainly changed from pressure. PET bottles have different operating conditions in different environments, so the rheology and viscosity can be manipulated in a molten condition of the PET bottle.
1. The injection molding machine is used. PET bottles have a low melting point after melting point, and the melting point is higher. Therefore, it is necessary to select an injection system with more temperature control sections and less self-conflict heat during plasticization, and the actual component of the product (water-containing material) cannot be smaller than the machine. 2/3 of the injection volume. According to these requirements, China's small and medium series PET special plasticizing system has been developed in recent years. The clamping force is selected according to more than 6300t/m2.
2, PET treatment. Because the PET bottle contains a lipid group and has a certain hydrophilicity, the pellet is more sensitive to water at high temperatures. When the moisture content exceeds the limit, the molecular weight of the PET bottles decreases of processing, and the product is colored and brittle. In this case, it is necessary to dry the material before processing, and the drying temperature is 150 ° C, more than 4 hours, generally 170 ° C, 3-4 hours. The airshot method can be used to check whether the data is completely boring. When using the materials, the material must be boring, pay attention to different drying temperatures and time constraints, and ensure that the PET bottles produced have outstanding product functions. The share of the recovered material should generally not exceed 25%, and the recovered material should be completely boring.
3. Staying moments. Never use excessive residence times to prevent molecular weight degradation. Try to prevent temperatures above 300 °Cs. If the shutdown is less than 15 minutes. It only needs to be air-aired; if it exceeds 15 minutes, it should be cleaned with viscosity PE and the barrel temperature will be lowered to PE temperature until it is turned on again. Strict handling is required when stopping the PET bottle, and the processing required at different temperatures are different, and the constraints on the time must be strictly controlled.
Please leave your Email or phone nomber, so we can contact you as soon as possible.