Vivian Zhang, Carrie Ou, Ilia Kevlishvili, Christina M. Hemmingsen, Joseph V. Accardo, Heather J. Kulik and Julia A. Kalow*,
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引用次数: 0
Abstract
Thioesters are an essential functional group in biosynthetic pathways, which has motivated their development as reactive handles in probes and peptide assembly. Thioester exchange is typically accelerated by catalysts or elevated pH. Here, we report the use of bifunctional aromatic thioesters as dynamic covalent cross-links in hydrogels, demonstrating that at physiologic pH in aqueous conditions, transthioesterification facilitates stress relaxation on the time scale of hundreds of seconds. We show that intramolecular hydrogen bonding is responsible for accelerated exchange, evident in both molecular kinetics and macromolecular stress relaxation. Drawing from concepts in the vitrimer literature, this system exemplifies how dynamic cross-links that exchange through an associative mechanism enable tunable stress relaxation without altering stiffness.
期刊介绍:
ACS Macro Letters publishes research in all areas of contemporary soft matter science in which macromolecules play a key role, including nanotechnology, self-assembly, supramolecular chemistry, biomaterials, energy generation and storage, and renewable/sustainable materials. Submissions to ACS Macro Letters should justify clearly the rapid disclosure of the key elements of the study. The scope of the journal includes high-impact research of broad interest in all areas of polymer science and engineering, including cross-disciplinary research that interfaces with polymer science.
With the launch of ACS Macro Letters, all Communications that were formerly published in Macromolecules and Biomacromolecules will be published as Letters in ACS Macro Letters.