PET is a important polyester raw materials, it is transparent, stable chemical properties, qualitative light, intensity (especially pressure), high mechanical properties, water resistance, resistance, so it is widely used in packing materials.PET besides mainly due to the rigid package beer, carbonated drinks, can also be used as a peanut butter, salad, biscuits, vegetables, spices, food packaging standard.In addition to the PET film can be used for food and other products packaging, metallized PET film (vacuum aluminum plating film) can improve the gas barrier property, different type of PET can be used in different applications.
The application of material PET bags
Is one of the main packaging materials, PET bottles as shortcomings of packaging materials for processing cost is higher, need to adopt two stepsMethod of blowing process, the hardness of small bottle.PET bottle is produced by injection blow molding a stretch forming process, a small piece of resin melt injection into the mold to form a tube billet, the second step is to blow up the tube billet compressed air, and a telescopic rod into the bottle at the bottom of the billet, and then be shaped.
The barrier property of PET material is not very high.If all beer or soda, oxygen can through the PET packing slow penetration, slow permeate out carbon dioxide, which means that the shelf life of carbon dioxide concentration in the beverage reduction rate and the increase of the oxygen rate limit.Some new techniques, such as adding blocking, multilayer composite coating method can solve this problem.Such as PET/polyethylene naphthalate formic acid 1, 3 yiding glycol ester (polytrimetylenenaphtalate, PTN) can improve the barrier property of carbon dioxide, and bactericidal performance;PET/MXD6 polyamide/oxygen absorption layer (oxygen scavenger) and the packaging of multilayer structure is widely used for carbonated beverage packaging;PET/EVOH/PE for bottled beer, beverage, water of packing.
