Related Experiment Video
Updated: Jun 12, 2025

Depolymerizable Olefinic Polymers Based on Fused-Ring Cyclooctene Monomers
Published on: December 16, 2022
Facile Depolymerization of Thermally Stable Polyetherethersulfone and Polyetheretherketone Using Hydroquinone and
Yasunori Minami1,2,3, Rena Honobe1, Shunsuke Tsuyuki1
1Interdisciplinary Research Center for Catalytic Chemistry (IRC3), National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, Ibaraki, 305-8565, Japan.
Abstract:
Super engineering plastics such as polyetheretherketone (PEEK) and polyetherethersulfone (PEES) exhibit thermal stability, chemical resistance, and mechanical strength. Such characteristics are attributed to their robust chemical structures composed of stable aryl ethers. These features make chemical recycling difficult. This is because it is necessary to overcome through the stability of the material and then precisely cleave the stable bonds. This study demonstrates the depolymerization of PEES and PEEK by hydroquinone in the presence of sodium hydroxide in 1,3-dimethyl-2-imidazolidinone (DMI) solvent at 150 °C. This method effectively provides monomeric products, diphenylsulfone and benzophenone having two 4-hydroxyphenoxy groups at both para positions. DMI solvent was the crucial factor for this transformation, since it enhanced the reactivity of hydroquinone to cleave the aryl ether bonds.
Related Concept Videos
Autoxidation of Ethers to Peroxides and Hydroperoxides
Preparation of Epoxides
Epoxides result from alkene oxidation, which can be achieved by a) air, b) peroxy acids, c) hypochlorous acids, and d) halohydrin cyclization.
Epoxidation with Peroxy Acids
Epoxidation of alkenes via oxidation with peroxy acids involves the conversion of a carbon–carbon double bond to an epoxide using the oxidizing agent meta-chloroperoxybenzoic acid, commonly known as MCPBA. Since the O–O bond of peroxy acids is very weak, the addition of electrophilic oxygen of...
Esters to Carboxylic Acids: Saponification
The reaction requires a base in stoichiometric amounts, which participates in the reaction and is not regenerated later. So, the base acts as a...
Acid-Catalyzed Dehydration of Alcohols to Alkenes
Oxidation of Phenols to Quinones
o-hydroxy phenols are oxidized to o-quinones and p-hydroxy phenols to p-quinones. Such redox reactions involve the transfer of two electrons and two protons. The reversible redox...
Hydrolysis of Chlorobenzene to Phenol: Dow Process

