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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)...
Autores principales: | , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
MDPI
2021
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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. |
format | Online Article Text |
id | pubmed-8124857 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2021 |
publisher | MDPI |
record_format | MEDLINE/PubMed |
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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