Bottled water is an upgraded product. Compared with the bottled water, the biggest advantage of bagged water is to fundamentally eliminate the "secondary pollution" of drinking water. The water in a bag is produced by atmospheric pressure and is discharged by positive pressure. The water in a barrel is produced by gas-water replacement and is discharged by negative pressure. Bags of drinking water is sealed all the way, from beginning to end not exposed to air, to avoid the secondary pollution, and bottled water to drink is drinking, completely open mode from a bucket full of water to drink the air became a full process of the essence of which is a process of drinking water is polluted, so the problem of "secondary pollution" of the bottled water is inevitable. In addition, bagged water takes up less space before and after use, is flexible and convenient in storage and transportation, and its application scope is more and more extensive. The packaging water bag for water bag is required to withstand extreme pressure, so it has higher requirements for the preparation of water bag film, which requires good toughness, strong pressure bearing capacity and strong anti-permeability performance. In addition, due to its contact with drinking water, it is required to be odor-free to guarantee water quality. It is difficult for conventional films to meet such performance requirements.
