What is the best type of plastic to store alcohol?
In the United States and Canada much of the plastic bottles used to package alcohol are made with PET (polyethylene terephthalate). I also know it is used in Europe.
This site may be useful - https://www.creativemechanisms.com/blog/everything-about-polyethylene-terephthalate-pet-polyester

I believe some bottles are'laminated' with several different plastics and PET being the 'contact' layer.

I have been told that plastic beverage bottles have a relatively short shelf life, but never had reason to research this.

Anyroad, this information might provide a starting point for your project