A novel PEG-based hydrogel possessing disulfide bonds: synthesis via click chemistry and study on swelling behavior

ABSTRACT

In this research, polyoxyethylene with alkyne end groups and two disulfide bonds in the polymer chain was synthesized through two consecutive esterification reactions from polyethylene glycol (PEG). A new PEG-based hydrogel with exceptional structural features was prepared from the polycycloaddition reaction of this macro-dialkyne with a triazidohydrin obtained from trimethylolpropane triglycidyl ether. The network structure of the hydrogel was investigated by FT-IR spectroscopy, elemental analysis, field emission-scanning electron microscopy (FE-SEM) and energy dispersive X-ray (EDX) spectroscopy. The swelling behavior of the prepared hydrogel in water was studied by drawing the graph of water uptake percentage versus time. It was found that the hydrogel has the ability to absorb water more than five times its dry weight within 12 h. The water uptake rate of the prepared hydrogel was compared with several other hydrogels with similar structure. In addition to water, the swelling behavior was also checked in a number of organic solvents with different dipole moments. The prepared hydrogel showed significant solvent uptake (slightly more than twice the dry weight) in methanol and N,N-dimethylformamide solvents.

Graphical abstract

KEYWORDS:

• Click chemistry
• disulfide bond
• PEG-based hydrogel
• swelling rate
• water uptake ability

Acknowledgments

The financial support of School of Chemistry-Damghan University is appreciated for this project.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was financially supported by School of Chemistry and Research Council of Damghan University.

Notes on contributors

Abbas Rezaei

Abbas Rezaei received his PhD in Organic Chemistry from Damghan University in February 2023. His field of study was focused on polymer hydrogels and polymer systems suitable for drug delivery. He received his BSc and MSc degrees from Ayatollah Amoli University and Ghadr Institute of Higher Education in 2015 and 2017, respectively.

Raheleh Gilani

Raheleh Gilani obtained her MSc and BSc degrees in Damghan University in 2021 and 2019, respectively. Her research interests are polymer synthesis and characterization, polymer composites and polymer hydrogels.

Hossein Behniafar

Hossein Behniafar is currently teaching and researching in the School of Chemistry - Damghan University. In March 2017, he succeeded in obtaining a professorship in the field of Polymer Chemistry. He studies fields such as epoxy resins, polyurethanes, electrically conductive polymers, polymer supports, drug-carrying polymers, and polymer hydrogels. He received his MSc, BSc, and PhD degrees in 1996, 1998, and 2003 from Mazandaran University, Sharif University of Technology, and Shiraz University, respectively.