Toward Making Poly(ethylene terephthalate) Degradable in Aqueous Environment

Abstract

Polyethylene terephthalate (PET) is a non‐biodegradable polymer, and it takes hundreds of years or longer to degrade in nature. In the current study, it is demonstrated that the addition of calcium oxide (CaO) into PET renders a degradable PET in an aqueous environment. Specifically, PET/CaO composite samples are prepared by melt mixing and compression molding, and the capability of hydrolysis of the composite in an aqueous environment is evaluated using different characterization and testing methods. The results show that the PET/CaO mixture is thermally stable during melt processing, and the resulting composite undergoes controllable hydrolysis in a water bath with calcium terephthalate as a main hydrolysis byproduct. The PET/CaO composite is mechanically strong; for example, a 75/25 PET/CaO sample shows a strength comparable to that of the pure PET polymer. The results further show that the hydrolysis of the PET/CaO composite may be promoted by addition of other fillers such as glass fibers. It is anticipated that the development of such a degradable PET material may impact a number of application areas where disposable packaging materials and water dissolvable composite products are desired.

A focused review on recycling and hydrolysis techniques of polyethylene terephthalate

“…Factors that affect reaction rate are temperature, pressure, proton or hydroxyl concentration, PET particle size, and the extent of surface wetting with the reaction medium. [193][194][195] F I G U R E 6 Aminolysis of polyethylene terephthalate.…”

“…So, hydrolysis is a heterogeneous reaction occurring at the surface of PET. Factors that affect reaction rate are temperature, pressure, proton or hydroxyl concentration, PET particle size, and the extent of surface wetting with the reaction medium 193–195 …”

Waste PET Plastic-Derived CoNi-Based Metal–Organic Framework as an Anode for Lithium-Ion Batteries

“…More importantly, it is abundant as a starting material from the recycling of polyethylene terephthalate and the metabolites of aromatic hydrocarbon oxidation . Poly­(ethylene terephthalate) (PET) is widely used in packaging and textiles due to its good mechanical properties, low permeability to moisture and gas, and high heat resistance. − According to statistics, global PET consumption has surpassed 24 million tons (62.8 billion bottles) per year and is continuing to rise. Because of its poor biodegradability, the current common practice of PET waste land filling has caused serious environmental problems.…”