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Abstract Cell engineering, soft robotics, and wearable electronics often desire soft materials that are easy to deform, self‐heal readily, and can relax stress rapidly. Hydrogels, a type of hydrophilic networks, are such kind of materials that can be made responsive to environmental stimuli. However, conventional hydrogels often suffer from poor stretchability and repairability. Here, hydrogels consisting of boronic ester dynamic covalent bonds in a double network of poly(vinyl alcohol)/boric acid and chitosan are synthesized, which demonstrate extreme stretchability (up to 310 times the original length), instant self‐healing (within 5 s), and reusability and inherent adhesion. Their instant stress relaxation stems from a low activation energy of the boronic ester bond exchange (≤20 kJ mol−1) and contributes to the extreme stretchability and self‐healing behaviors. Various water‐dispersible additives can be readily incorporated in the hydrogels via hand kneading for potential applications such as soft electronics, bio‐signal sensing, and soft artificial joints.
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This content will become publicly available on May 1, 2026
Fabrication of self-repairing and low-swelling polymer network via dynamic boronic ester bonds for enhanced membranes longevity and stability
Membrane technology has become a promising solution for a wide range of separation processes, including wastewater treatment, solvent recovery, and oil–water separation, due to its low energy consumption, cost-effectiveness, and minimal space needs. However, membrane damage caused by suspended pollutants or improper handling remains a challenge, often leading to decreased filtration capability and the need for replacement of membrane modules. Self-repairing membranes have emerged as a new solution, with various materials demonstrating autonomous healing properties through dynamic bonds such as hydrogen bonds or boronic ester bonds. However, many of these self-repairing membranes suffer from excessive swelling in water, compromising their mechanical stability. Herein, we report a self-repairing and low-swelling polymer network based on dopamine acrylamide (DA) and n-butyl acrylate (BA), crosslinked with p-phenylenediboronic acid (PDBA). The boronic ester bond formation between catechol and boronic acid groups confers self-healing properties to the polymer, while the hydrophobic nature of BA minimizes swelling in water. The polymer exhibits a low swelling ratio of 2.1% after 7 days of submersion in water. A cellulose-based filter paper coated with the polymer demonstrated that it can recover its water flux up to 91% after repairing damage. Lastly, an ultrafiltration polyethersulfone (PES)-based filter coated with the polymer demonstrated that it recovers its solute rejection capability after repairing damage.
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- Award ID(s):
- 1944314
- PAR ID:
- 10593057
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Journal of Industrial and Engineering Chemistry
- ISSN:
- 1226-086X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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