Renewable PET from Recovered Plastic Waste

Poly(ethylene terephthalate) (PET) is a key component of many global plastic products; however, concerns regarding the global accumulation of plastic debris have motivated the development of recyclable and degradable plastics. Thus, we focus on preparing polymers from starting materials that are derived from plastic waste (Control PET), and we then compare the thermomechanical, optical, and end-use properties of the materials to their control plastic counterparts. We prepared different polymers (Recycled PET) from a set of tailored reaction conditions that were refined based on a series of iterative structure–property evaluations. For instance, we quantified the glass transition and melting temperatures of the resultant polymers, and these were benchmarked against those of Control PET plastics. We established the mechanical properties of the Control PET sample and compared them to those of the polymers synthesized from starting materials. The Recycled PET showed excellent performance, maintaining nearly all (around 92%) of the control's ultimate tensile strength and storage modulus (E′). The Recycled PET exhibited stress relaxation behavior due to the presence of activated ester groups within the polymer chains. Hydrolytic depolymerization breaks Recycled PET down into its basic components, enabling it to be recycled again and again, reducing reliance on control materials. Therefore, this work offers insights into a design strategy for PET, considering its ease of synthesis, abundant precursor availability, and promising end-use properties.