Welding and reprocessing of disulfide‐containing thermoset epoxy resin exhibiting behavior reminiscent of a thermoplastic. Issue 47 (14th June 2020)

• Record Type: Journal Article
• Authors: Memon, Hafeezullah; Wei, Yi
• Is Part Of: Journal of applied polymer science. Volume 137:Issue 47(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-06-14
• Subjects: mechanical properties -- resins -- thermogravimetric analysis (TGA) -- thermoplastics -- thermosets; Polymers -- Periodicals; Polymerization -- Periodicals; 668.9
• DOI: 10.1002/app.49541
• Languages: English
• ISSNs: 0021-8995

Abstract

Abstract: Thermoset resins generally lack the ability to be welded or reprocessed like thermoplastics because of their cross‐links. Increasing use of fiber‐reinforced composites in large structures, such as rail and aircraft parts, as well as wind blades, calls for better ways to repair damages and be compliant with recycling and environmental regulations. In this article, an epoxy resin containing disulfide bonds was prepared and characterized by Fourier transform infrared, 1 H‐NMR, and 13 C‐NMR. The dynamic nature of the disulfide bonds allowed the cured epoxy resin to be welded like thermoplastics, and the welded joints had strength that matched the resin's cohesive strength. It could also be reprocessed with 90% tensile strength retention after three reprocessing cycles, allowing the parts to be repaired instead of being replaced. In addition, the cured resin was chemically degradable in a thiol‐based solvent, allowing it to be recycled in closed‐loop processes. Moreover, the cured epoxy resin showed a glass transition temperature of 116°C, demonstrating its potential for advanced composite applications. Abstract :