Tempered glass does not contain plastic. No glass contains plastic. The formula to make glass has been known for centuries. Tempering is a thermal process, it d

Tempered glass does not contain plastic. No glass contains plastic. The formula to make glass has been known for centuries. Tempering is a thermal process, it doesn’t change the chemistry of the product. Old school pyrex involved the addition of Boron —- no hydrocarbons in the mix.