Swelling Behavior of Polyacrylamide–Cellulose Nanocrystal Hydrogels: Swelling Kinetics, Temperature, and pH Effects

• Published in: Materials Vol. 12; no. 13; p. 2080
• Main Authors: Jayaramudu, Tippabattini, Ko, Hyun-U, Kim, Hyun Chan, Kim, Jung Woong, Kim, Jaehwan
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 28.06.2019; MDPI
• Subjects: Acrylamide; Cellulose; Cotton; Fourier transforms; Free radicals; Hydrogels; Hydroxyl groups; Kinetics; Microscopy; Nanocrystals; Nanoparticles; Polyacrylamide; Polymerization; Polymers; Polyvinyl alcohol; Retention; Room temperature; Silicon wafers; Smart materials; Spectrum analysis; Swelling ratio; Temperature effects; Thermogravimetric analysis; Tissue engineering; United States > US; Japan; pH-sensitive; diffusion; hydrogels; swelling; cellulose nanocrystal
• ISSN: 1996-1944; 1996-1944
• DOI: 10.3390/ma12132080

This paper reports swelling behavior of cellulose nanocrystal (CNC)-based polyacrylamide hydrogels prepared by a radical polymerization. The CNC acts as a nanofiller through the formation of complexation and intermolecular interaction. FTIR spectroscopy and XRD studies confirmed the formation of intermolecular bonds between the acrylamide and hydroxyl groups of CNC. The swelling ratio and water retention were studied in de-ionized (DI) water at room temperature, and the temperature effect on the swelling ratio was investigated. Further, the pH effect on the swelling ratio was studied with different temperature levels. Increasing the pH with temperature, the prepared hydrogel shows 6 times higher swelling ratio than the initial condition. The swelling kinetics of the developed hydrogels explains that the diffusion mechanism is Fickian diffusion mechanism. Since the developed hydrogels have good swelling behaviors with respect to pH and temperature, they can be used as smart materials in the field of controlled drug delivery applications.