Watch out for the word "plastic," "polycarbonates," etc. There exist many plastics and polycarbonates, physically quite different from each other. Both terms are very general name that mean very broad (and nearly the same) range of materials.(posted 8350 days ago)One reason people recommend "glass" is partly idiot-proof factor. Glass is glass, at least in their mind. (photographers should know at least a few different glasses!!) It's not the absolute necessity.
Beverage bottles, whether sold with something inside or empty, can be used to store photographic chemicals quite satisfactorily. The bottle must be well made in terms of good sealing. You can squeeze the bottle hard to see if air leaks, or fill it with water and squeeze real hard to see if water leaks, etc. Materials like HDPE (high-density polyethylene) or PET (polyethylene terephthalate) are best materials as they are strong, hard to break, have quite low absorption, adsorption, permeability, etc. PET is a common clear plastic used for water and juice often sold on the shelf at room temperature. HDPE is used for many kitchen storage bottles. HOWEVER, CHECK WHAT THE BOTTLE IS MADE FROM BEFORE USING. Usually, you should be able to find a recycle mark indicating the material by the arabic number inside three arrow triangle, and the acronim like PET and HDPE are indicated below the mark. Many liquid chemicals for photography processing are shipped in HDPE bottles.
There is slight absorption and adsorption even by these two specific kinds of plastic material. Reusing beverage bottles for the first time should not be a problem as long as they are thoroughly washed in hot water. Once stored a photo chemical, I recommend to reuse the bottle for the same chemical. If you need to reuse the bottle for another chemical, I suggest to shift them down along the photo processing steps. Developer bottle can be now reused for stop or fix storage. Use fresh bottle for developer, wash aid agents, Photo-Flo and Sistan.
I've seen comments about accordion bottles that they are not as good as glass bottles. That's consistent with my experience, but I have never had a trouble with PET and HDPE bottles reused from bottled water and juices, as well as ones sold as kitchen storage containers.
One thing I do to ensure good shelf life of my developers is to make part A and B stock solutions, with A containing developing agents and preservatives, whereas B containing accelerators. If the formula uses buffer, acid goes to A and base goes to B. I make double the concentration of each so that I can mix 1 part A and 1 part B to get full strength solution. If it is high sulfite formula I don't want to put 200g sulfite in 1 liter of part A, so I put 100g in A and another 100g in B. Prepared this way, many home made liquid developers can be stored for least a few months, probably longer.
Finally, these beverage bottles are usually transparent or lightly colored, and therefore store the chemicals in dark shelves. Also always label each bottles.
Reuse is one of the best ways to recycle whenever practical.