The important factors affecting the PET food bottle blow molding process----Bottle embryo
The important factors affecting the PET food bottle blow molding process----Bottle embryo
The bottle embryo is one of the important factors affecting the blow molding process of PET food bottle.
When preparing blow molding bottles, PET slices are first injected into the preform. It requires that the proportion of secondary recovered materials should not be too high (less than 5%), The Times of recovery should not be more than twice, and the molecular weight and viscosity should not be too low (molecular weight is 31000-50000, and the characteristic viscosity is 0.78-0.85cm3/g).
Injection molded bottle preforms should be stored for more than 48 hours before use.The unused preform after heating shall be stored for more than 48 hours before reheating.The preform shall not be stored for more than six months.
The quality of preform depends largely on the quality of PET material, so the material easy to be blown and shaped should be selected, and a reasonable forming process of preform should be developed.The experimental results show that the imported raw materials are easier to blow molding than the domestic materials for the same viscosity PET preform.And the same batch of preform, production date is different, blow molding process may also have a great difference.
The advantages and disadvantages of the bottle preform determine the difficulty of blow molding process. The requirements for the bottle preform are purity, transparency, impurity free, same color, length of injection point and appropriate halo spot.
The quality of preform depends largely on the quality of PET material, so the material easy to be blown and shaped should be selected, and a reasonable forming process of preform should be developed.The experimental results show that the imported raw materials are easier to blow molding than the domestic materials for the same viscosity PET preform.And the same batch of preform, production date is different, blow molding process may also have a great difference.
The advantages and disadvantages of the bottle preform determine the difficulty of blow molding process. The requirements for the bottle preform are purity, transparency, impurity free, same color, length of injection point and appropriate halo spot.
