Seawater-Degradable and Antibacterial Epoxy Thermosets Employing Betaine Ester Linkages

Abstract

Poor degradation and microbial contamination are two major challenges associated with the application of thermoset resins in marine settings. Here, the synthesis of betaine ester-functionalized epoxy resins with tunable degradation and antibacterial activity in seawater-like environments is presented. Chloroacetate-decorated epoxy resins were first synthesized using a ring-opening reaction and subsequently reacted with tertiary amine-based curing agents. The resulting betaine ester-decorated epoxy thermosets featured a yield strength exceeding 80 MPa and tunable degradation capability. Rapid degradation was realized under mild alkali conditions, corresponding approximately to weakly alkaline seawater conditions. Integration of cetyl chloroacetate further increased the betaine ester content and bactericidal performance. A bactericide rate of 99.34% against Staphylococcus aureus of MF10-CCA1-PMD was achieved, which compares favorably to that of established antibacterial agents. The results demonstrate an effective route for realizing functionalized epoxy resins that could advance the development of thermosetting materials with enhanced functionality and reduced environmental cost for marine environments.

Degradable π-Conjugated Polymers

“…For certain applications, such as biodegradable food packaging with integrated sensors, the complete degradation of π-conjugated polymers in the natural environment without chemical manipulation would be ideal for postconsumer management of electronic waste. Bockstaller and co-workers 143 recently developed a betaine ester-functionalized epoxy resins that completely degraded via hydrolysis in seawater at room temperature in under one month. Although there are currently no reports of a π-conjugated polymer that can degrade in seawater, we can use this example as inspiration to design π-conjugated polymers for environmental depolymerization without needing an external chemical stimulus.…”

Broad-Spectrum Antimicrobial Polymer-Coated Fabrics via Commodity Polystyrene Upcycling

“…While this latest pandemic was caused by a virus, infections by pathogenic bacteria and fungi represent no less of a threat due to the emergence of multidrug resistance (MDR). , This critical threat to human health posed by MDR “superbugs” has been attributed to our overuse and misuse of antibiotics and antifungals in past decades. To overcome this problem, functional materials such as antimicrobial peptides, synthetic cationic polymers, − antimicrobial nanomaterials, composites, − and coatings − have been explored. While effective, antimicrobial peptides tend to be costly and susceptible to enzymatic degradation .…”