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Hydrophobically-Modified PEG Hydrogels with Controllable Hydrophilic/Hydrophobic Balance

This work reports on a novel method to synthesize hydrophobically-modified hydrogels by curing epoxy monomers with amines. The resulting networks contain hydrophilic poly(ethylene glycol) (PEG) segments, poly(propylene glycol) (PPG) segments, and C(18) alkyl segments. By varying the content of C(18)...

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Detalles Bibliográficos
Autores principales: Bignotti, Fabio, Baldi, Francesco, Grassi, Mario, Abrami, Michela, Spagnoli, Gloria
Formato: Online Artículo Texto
Lenguaje:English
Publicado: MDPI 2021
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8124857/
https://www.ncbi.nlm.nih.gov/pubmed/34066409
http://dx.doi.org/10.3390/polym13091489
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author Bignotti, Fabio
Baldi, Francesco
Grassi, Mario
Abrami, Michela
Spagnoli, Gloria
author_facet Bignotti, Fabio
Baldi, Francesco
Grassi, Mario
Abrami, Michela
Spagnoli, Gloria
author_sort Bignotti, Fabio
collection PubMed
description This work reports on a novel method to synthesize hydrophobically-modified hydrogels by curing epoxy monomers with amines. The resulting networks contain hydrophilic poly(ethylene glycol) (PEG) segments, poly(propylene glycol) (PPG) segments, and C(18) alkyl segments. By varying the content of C(18) segments, networks with different hydrophilic-lipophilic balance (HLB) are obtained. All networks show an amphiphilic behavior, swelling considerably both in organic solvents and in aqueous media. In the latter they display a thermosensitive behavior, which is highly affected by the network HLB and the pH of the solution. A decrease in HLB results in an increment of the polymer weight content (w(p)) due to hydrophobic association. Furthermore, a reduction in HLB induces a remarkable increase in initial modulus, elongation at break and tensile strength, especially when w(p) becomes greater than about 10%. Low field nuclear magnetic resonance (LF-NMR) experiments evidence that, when HLB decreases, a sudden and considerable increase in hydrogel heterogeneity takes place due to occurrence of extensive physical crosslinking. Available data suggest that in systems with w(p) ≳ 10% a continuous physical network superimposes to the pre-existing chemical network and leads to a sort of double network capable of considerably improving hydrogel toughness.
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spelling pubmed-81248572021-05-17 Hydrophobically-Modified PEG Hydrogels with Controllable Hydrophilic/Hydrophobic Balance Bignotti, Fabio Baldi, Francesco Grassi, Mario Abrami, Michela Spagnoli, Gloria Polymers (Basel) Article This work reports on a novel method to synthesize hydrophobically-modified hydrogels by curing epoxy monomers with amines. The resulting networks contain hydrophilic poly(ethylene glycol) (PEG) segments, poly(propylene glycol) (PPG) segments, and C(18) alkyl segments. By varying the content of C(18) segments, networks with different hydrophilic-lipophilic balance (HLB) are obtained. All networks show an amphiphilic behavior, swelling considerably both in organic solvents and in aqueous media. In the latter they display a thermosensitive behavior, which is highly affected by the network HLB and the pH of the solution. A decrease in HLB results in an increment of the polymer weight content (w(p)) due to hydrophobic association. Furthermore, a reduction in HLB induces a remarkable increase in initial modulus, elongation at break and tensile strength, especially when w(p) becomes greater than about 10%. Low field nuclear magnetic resonance (LF-NMR) experiments evidence that, when HLB decreases, a sudden and considerable increase in hydrogel heterogeneity takes place due to occurrence of extensive physical crosslinking. Available data suggest that in systems with w(p) ≳ 10% a continuous physical network superimposes to the pre-existing chemical network and leads to a sort of double network capable of considerably improving hydrogel toughness. MDPI 2021-05-06 /pmc/articles/PMC8124857/ /pubmed/34066409 http://dx.doi.org/10.3390/polym13091489 Text en © 2021 by the authors. https://creativecommons.org/licenses/by/4.0/Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
spellingShingle Article
Bignotti, Fabio
Baldi, Francesco
Grassi, Mario
Abrami, Michela
Spagnoli, Gloria
Hydrophobically-Modified PEG Hydrogels with Controllable Hydrophilic/Hydrophobic Balance
title Hydrophobically-Modified PEG Hydrogels with Controllable Hydrophilic/Hydrophobic Balance
title_full Hydrophobically-Modified PEG Hydrogels with Controllable Hydrophilic/Hydrophobic Balance
title_fullStr Hydrophobically-Modified PEG Hydrogels with Controllable Hydrophilic/Hydrophobic Balance
title_full_unstemmed Hydrophobically-Modified PEG Hydrogels with Controllable Hydrophilic/Hydrophobic Balance
title_short Hydrophobically-Modified PEG Hydrogels with Controllable Hydrophilic/Hydrophobic Balance
title_sort hydrophobically-modified peg hydrogels with controllable hydrophilic/hydrophobic balance
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8124857/
https://www.ncbi.nlm.nih.gov/pubmed/34066409
http://dx.doi.org/10.3390/polym13091489
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