Track: High School STEM Competition

Abstract

Polyethylene terephthalate (PET) is a common synthetic polymer material, which has a wide range of applications. However, with the overuse of humans, more and more PET The product was found to be improperly recycled.

The alcoholysis method is a depolymerized PET method with simple reaction conditions, a mild reaction process, and less unnecessary by-products.   Also, the ester exchange reaction in the esterification reaction is combined with the alcoholysis method for the reaction.  The alcohol used in this study-ethylene glycol (EG) can be esterified with the free acid.  Because zinc metal is an amphoteric substance, can catalyze the reaction and produce new esters and new alcohols.  Use zinc in waste batteries as a catalyst to depolymerize PET into monomer polyethylene terephthalate (BHET) and discuss in-depth the factors affecting the reaction and its development and application.  Using zinc from waste batteries as a catalyst is not only low cost, but also more in line with the core of this research-green chemistry.  This research has searched through optimal conditions and found that 5 grams of PET can be depolymerized when the catalyst usage is 0.2 grams, the reaction time is 4 hours, and the reaction temperature is 180 degrees.