Related Experiment Video
Updated: May 25, 2025

Designed for Molecular Recycling: A Lignin-Derived Semi-aromatic Biobased Polymer
Published on: November 30, 2020
Full Recovery of Epoxy Resin Wastes into Bisphenol A and Epoxy Monomers via Lewis Acid
Xiaohui Li1, Xuehui Liu2, Lulu Liu1
1Sichuan University - Wangjiang Campus: Sichuan University, The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials (MoE), National Engineering Laboratory of Eco-Friendly Polymeric Materials (Sichuan), College of Chemistry, State Key Laboratory of Polymer Materials Engineering, 610064, Chengdu, CHINA.
Abstract:
Epoxy resins (EPs) are important thermosetting plastics and difficult to recycle because of their stable cross-linked structure. In this study, we report a full recovery strategy for the conversion of EPs into high-value platform compounds, i.e., bisphenol A (BPA) and epoxy monomers such as 4,4'-methylenebis (N,N'-diglycidylaniline) (AG80), which involves the selective breaking of the C(sp3)─O bond using commercially available boron trichloride (BCl3), the reconstruction of the broken C(sp3)─N bond and the cyclization of the hydroxy groups. The yield of BPA is 93 wt% with a purity of 99%, and the yield of AG80 is 96 wt% with an epoxy value of 0.43. 100% recovery of EP elements was achieved theoretically, and the actual mass recovery of the EPs is as high as 91%. Because of its versatility, simplicity of operation, mild reaction conditions, and recyclability of all solvents and by-products, this approach shows the potential in solving the current recycling challenges associated with EP waste.
Related Concept Videos
Esters to Carboxylic Acids: Acid-Catalyzed Hydrolysis
During hydrolysis, the ester is first activated towards nucleophilic attack through the protonation of the carboxyl oxygen atom by the acid catalyst. The protonation makes the ester carbonyl carbon more electrophilic. In the next step, water acts as a nucleophile and adds to the...
Carboxylic Acids to Esters: Acid-Catalyzed (Fischer) Esterification Overview
Alkylation of β-Diester Enolates: Malonic Ester Synthesis
Acid-Catalyzed Dehydration of Alcohols to Alkenes
Acid-Catalyzed Ring-Opening of Epoxides
Carboxylic Acids to Esters: Acid-Catalyzed (Fischer) Esterification Mechanism

