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Introducing facile regenerability into adsorbent materials can potentially increase sustainability in water treatment systems enabled by extended use. Herein, we detail our recent syntheses of dynamic nanostructured worm-gel materials and their implementation as regenerable adsorbents for water treatment. Photo-controlled atom transfer radical polymerization-induced self-assembly (PhotoATR-PISA) was employed to synthesize various polymer nanostructures, including dispersed spheres, worms, and vesicles, and nanostructured worm-gels, via the synthesis and simultaneous in situ assembly of BAB triblock copolymers. Two dynamic, disulfide-functionalized macroinitiators (SS-MI-1 and 2)with different degree of polymerization and one nondynamic macroinitiator (CC-MI) were synthesized via polymerization of oligo(ethylene glycol methyl ether methacrylate) (OEGMA). PhotoATR-PISA was then implemented via the chain extension fromSS-MI-1, 2 and CC-MI with glycidyl methacrylate (GMA) or benzyl methacrylate (BMA) forming BAB-type triblock copolymer nanoparticles in situ. The final morphology in PhotoATR-PISA was influenced not only by conventional factors such as solids content and block DP but also by unimer exchange rates yielding arrested, nanostructured worm-gels in many instances and arrested vesicle-gels in one instance. These PISA-gel materials were implemented as adsorbents for phenanthrene, a model compound registered as a priority pollutant by the US EPA, from aqueous solutions. The chemical tunability of these materials enabled enhanced, targeted removal of phenanthrene facilitated by π−π interactions, as evidenced by the increased adsorption capacities of PBMA-based PISA-gels when compared to PGMA. Furthermore, the dynamicity of disulfide worm-gels (SS-WG) enabled disulfide exchange-induced regeneration stimulated by UV light. This UV-responsive exchange was investigated for POEGMA macroinitiators as well as dissolved triblock copolymers, dispersed nanoparticles, and SS-WG materials. Finally, the regenerability of the PNT-saturated SS-WG adsorbents induced by UV irradiation (λ = 365 nm) was examined and compared with control worm-gels absent of disulfides, demonstrating enhanced recovery of adsorption capacity under mild irradiation conditions.
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This content will become publicly available on September 8, 2026
Changing Self‐Assembly Through Degradation: Phenyl Vinyl Ketone Polymer Nanoparticles Under Light
Abstract Photodegradable nanoparticles with sphere, worm, and vesicle morphologies were synthesized following polymerization induced self‐assembly (PISA), incorporating a photoresponsive phenyl vinyl ketone (PVK) block and a nonphoto responsive 2‐hydroxypropyl methacrylamide (HPMA) block. The photodegradation of nanoparticles under UV revealed that the initial shapes of sphere and vesicle particles are retained even until 7 h and after 24 h of photo‐induced degradation, respectively, despite a significant reduction in molecular weight (Mn). This could be due to the assembly of degraded PVK fragments in the hydrophobic region, maintaining the relative hydrophilic to hydrophobic ratio. However, worm nanoparticles exhibited a fast morphology reversal after 2 min of degradation, yielding sphere nanoparticles. Therefore, photo responsive PVK nanoparticles with morphology and conversion‐dependent degradation behavior were explored. Furthermore, undegraded and degraded nanoparticle coatings exhibited different surface properties, determined by contact angle measurements, with both morphology and degradation impacting the surface properties. Finally, the PVK nanoparticles could encapsulate molecules and release them upon degradation. Therefore, this study can ultimately be applied to numerous fields due to the potential uses of degradable polymers in various material systems, especially for the controlled release of agrochemicals, cleaning agents, or antifungal agents, as well as to enable surface modifications upon degradation.
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- Award ID(s):
- 2203727
- PAR ID:
- 10644130
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- ISSN:
- 1433-7851
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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