What material is the drink bottle cap

Update:14 Mar 2020

The materials used are polyethylene (PE), polyvinyl chloride (PVC), polyethylene terephthalate (PET), etc.
Usually, mineral water bottles are made of PVC or pet, carbonated beverage bottles are made of pet, cool beverage bottles, liquid food bottles are made of PVC and PE, detergent bottles, cosmetics bottles, milk bottles and Lactobacillus drinks are mostly made of PE.

Extended data:
Plastic is a kind of high molecular compound, which is polymerized by addition polymerization or polycondensation reaction with monomer as raw material. It is commonly known as plastics or resin. It can change the composition and form freely. It is composed of synthetic resin, filler, plasticizer, stabilizer, lubricant, pigment and other additives.
The main component of plastics is resin. Resin is a term originally derived from the lipids secreted by animals and plants, such as rosin, shellac, etc. resin refers to polymer compounds that have not been mixed with various additives.
Resin accounts for 40% - 100% of the total weight of plastic. The basic properties of plastics mainly depend on the nature of resins, but additives also play an important role. Some plastics are basically composed of synthetic resins, without or without additives, such as plexiglass, polystyrene, etc.
The so-called plastic, in fact, is a kind of synthetic resin. Its shape is similar to the pine resin in the natural resin. It is artificially synthesized by chemical means, and is called plastic.