Why do not you use plastic bottled beer
Plastic is more permeable than glass (the glass itself can not penetrate oxygen and carbon dioxide). In other words, beer (or other soft drinks) in the plastic bottle than in the glass bottle easier to run, become dull, because the beer can make bubbles bubble more easily lost carbon dioxide. Glass also has a benefit, it does not taste, and will not be installed in the inside of the chemical reaction.
While the plastic is full of chemical composition, it is very likely to infiltrate your drink, ruined your beer. For example, polyester plastic containers in the manufacture, often using antimony as a catalyst, the residual antimony may penetrate the beverage.
At room temperature or below room temperature, the content of antimony in the beverage harmless to the human body, once the temperature increases, antimony content will rise. So, if in summer or other warm places, drinks in the sealed warehouse for a few months, of which the antimony content is much higher than the standard.