Work

Characterization of Cross-Linking in Guar Gum Hydrogels via the Analysis of Thermal Decomposition Behavior and Water Uptake Kinetics

Year: 2023

Type: article

Abstract: This study aimed to explore a test method for evaluating the effective cross-linking density of hydrogels. A guar gum–epichlorohydrin hydrogel (GEH) was prepared using guar gum (GG) as the raw material and epichlorohydrin (ECH) as the cross-linking agent. The thermal and mechanical properties, equilibrium swelling rate (ESR), water uptake (WU), and mass cross-linking degree of the hydrogels were assessed. Furthermore, the diffusion behavior of water molecules in the freeze-dried GEH was investigated. The experimental results showed the significance of the initial decomposition temperature (Ti) and final decomposition temperature (Tf) of the freeze-dried GEHs in determining the effective cross-linking density. The water uptake kinetics of the freeze-dried GEH was consistent with the linear fitting of the pseudo-second-order kinetic model and nonlinear fitting of the Fickian diffusion model, suggesting that chemisorption dominated the water absorption process in the GEH. Therefore, the effective cross-linking density of the hydrogels could be determined from the thermodynamic analysis and the diffusive behavior of water molecules in the gels. The thermal stability and water diffusion kinetics of the hydrogels were closely linked to the effective cross-linking density and pendant modification.

Source: Sustainability

DOI: 10.3390/su15129778

Authors: Yanjiao Lan, Zhoujian Xie, Ting Wang, Jianfang Lu, Pengfei Li, Jianxin Jiang

Institutions: Guangxi Minzu University, Beijing Forestry University

Language: English

Topic: Hydrogels: synthesis, properties, applications

Subfield: Molecular Medicine

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

Open Access status: gold

Estimated APC paid: $2,447

Funder: Natural Science Foundation of Guangxi Province