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In this work, we designed and fabricated a nanoscopic sugar-based magnetic hybrid material that is capable of tackling environmental pollution posed by marine oil spills, while minimizing potential secondary problems that may occur from microplastic contamination. These readily-defined magnetic nanocomposites were constructed through co-assembly of magnetic iron oxide nanoparticles (MIONs) and a degradable amphiphilic polymer, poly(ethylene glycol)- b -dopamine-functionalized poly(ethyl propargyl glucose carbonate)- b -poly(ethyl glucose carbonate), PEG- b -PGC[(EPC-MPA)- co -(EPC-DOPA)]- b -PGC(EC), driven by supramolecular co-assembly in water with enhanced interactions provided via complexation between dopamine and MIONs. The composite nanoscopic assemblies possessed a pseudo -micellar structure, with MIONs trapped within the polymer framework. The triblock terpolymer was synthesized by sequential ring-opening polymerizations (ROPs) of two glucose-derived carbonate monomers, initiated by a PEG macroinitiator. Dopamine anchoring groups were subsequently installed by first introducing carboxylic acid groups using a thiol–yne click reaction, followed by amidation with dopamine. The resulting amphiphilic triblock terpolymers and MIONs were co-assembled to afford hybrid nanocomposites using solvent exchange processes from organic solvent to water. In combination with hydrophobic interactions, the linkage between dopamine and iron oxide stabilized the overall nanoscopic structure to allow for the establishment of a uniform globular morphology, whereas attempts at co-assembly with the triblock terpolymer precursor, lacking dopamine side chains, failed to afford well-defined nanostructures. The magnetic hybrid nanoparticles demonstrated high oil sorption capacities, ca. 8 times their initial dry weight, attributed, in part, to large surface areas leading to effective contact between the nanomaterials and hydrocarbon pollutants. Moreover, the naturally-derived polymer framework undergoes hydrolytic degradation to break down into byproducts that include glucose, ethanol and dopamine if not recovered after deployment, alleviating concerns of potential microplastic generation and persistence.
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Glucose‐derived superabsorbent hydrogel materials based on mechanically‐interlocked slide‐ring and triblock copolymer topologies
Abstract A series of glucose‐based degradable superabsorbent hydrogels with potential to tackle issues associated with sustainability, flooding, and drought has been designed and fabricated. These hydrophilic networks were constructed through integrating glucose as a primary building block –into cyclic oligomers and block polymers, which were combined into mechanically‐interlocked slide‐ring crosslinked materials. Crosslinking of slide ring α‐cyclodextrin/poly(ethylene glycol)‐type polyrotaxanes with acid‐functionalized ABA triblock copolymers comprised of mercaptopropionic acid‐functionalized poly(glucose carbonate (ethyl propargyl carbonate))‐b‐poly(ethylene glycol)‐b‐mercaptopropionic acid‐functionalized poly(glucose carbonate (ethyl propargyl carbonate)), afforded degradable superabsorbent hydrogels through establishment of chemically‐labile ester linkages, in addition to glycosidic and carbonate groups of the polymer precursors. With an emphasis on development of fundamental synthetic design strategies to achieve high‐performance superabsorbent hydrogels that could behave as robust materials, which are derived from natural components and exhibit hydrolytic degradability, effort went into optimization of the composition, structure, and topology leading to water uptake capacities >30× by mass. Investigations of composition‐structure‐topology‐morphology effects on properties as a function of variations of PEG main chain length, degree of α‐cyclodextrin coverage, and concentration of pre‐gel solution, indicated that the slide‐ring polymer and triblock copolymer networks feature high water uptake, tunable mechanical properties, and sustainability with construction from renewable natural products and in‐built degradability.
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- Award ID(s):
- 1905818
- PAR ID:
- 10389087
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Polymer Science
- Volume:
- 61
- Issue:
- 10
- ISSN:
- 2642-4150
- Format(s):
- Medium: X Size: p. 937-950
- Size(s):
- p. 937-950
- Sponsoring Org:
- National Science Foundation
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