This paper discusses the structure morphology and the thermal and swelling behavior of physically crosslinked hydrogels, obtained from applying four successive freezing-thawing cycles to poly (vinyl alcohol) blended with various amounts of κ-carrageenan. The addition of carrageenan in a weight ratio of 0.5 determines a twofold increase in the swelling degree and the early diffusion coefficients of the hydrogels when immersed in distilled water, due to a decrease in the crystallinity of the polymer matrix. The diffusion of water into the polymer matrix could be considered as a relaxation-controlled transport (anomalous diffusion). The presence of the sulfate groups determines an increased affinity of the hydrogels towards crystal violet cationic dye. A maximum physisorption capacity of up to 121.4 mg/g for this dye was attained at equilibrium.
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http://dx.doi.org/10.3390/polym12030560 | DOI Listing |
Langmuir
December 2024
Key Laboratory of Functional Polymer Materials of Ministry of Education and College of Chemistry, Nankai University, Tianjin 300071, China.
Polyelectrolyte complex (PEC) hydrogels provide a promising strategy to develop a class of physically cross-linked networks characterized by exceptional toughness and self-healing properties. However, the precise control of the microstructure and the enhancement of mechanical properties still pose challenges in the field of PEC hydrogels. Herein, we propose a strategy to manipulate the structure of PEC with competitively charged surfactant micelles, leveraging the spatially confined surface charge and excluded volume effects to overcome coacervation issues associated with the PEC, thus achieving a simple one-step preparation of macroscopically uniform and tough PEC hydrogels.
View Article and Find Full Text PDFInt J Biol Macromol
December 2024
School of Physics and Electronic Information, Yan'an University, Yan'an 716000, China; Shaanxi Key Laboratory of Intelligent Processing for Big Energy Data, Yan'an 716000, China.
With the global emphasis on green and sustainable development, sodium alginate-based hydrogels (SAHs), as a renewable and biocompatible environmental material, have garnered widespread attention for their research and application. This review summarizes the latest advancements in the study of SAHs, thoroughly discussing their structural characteristics, formation mechanisms, and current applications in various fields, as well as prospects for future development. Initially, the chemical structure of SA and the network structure of hydrogels are introduced, and the impact of factors such as molecular weight, crosslinking density, and environmental conditions on the hydrogel structure is explored.
View Article and Find Full Text PDFACS Food Sci Technol
December 2024
Department of Food Engineering, Middle East Technical University (METU), Ankara 06800, Turkey.
Noncentrifugal sugar (NCS) is an unrefined, dark brown sugar containing minerals and plant secondary metabolites, unlike refined white sugar (WS). This study explored using NCS in confectionary jellies as an alternative sugar. We used different concentrations of NCS and WS to prepare low methoxyl pectin (LMP) confectionery gels characterized by their physical and rheological properties along with time-domain nuclear magnetic resonance (TD-NMR) relaxometry.
View Article and Find Full Text PDFInt J Biol Macromol
December 2024
College of Food Science and Engineering, Changchun University, Changchun 130022, China. Electronic address:
Insufficient hydrophobicity and mechanical properties pose significant challenges in the development of starch-based degradable films. This study prepared modified (crosslinked, acetylated, and crosslinked & acetylated) cassava starch films, and different concentrations of strengthening agents (polyvinyl alcohol, sodium alginate, gelatin, and hyaluronic acid) were added to produce modified starch composite films. The physical properties, structure characteristics, and degradability of these films were systematically evaluated.
View Article and Find Full Text PDFAdv Healthc Mater
December 2024
John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138, USA.
Both rigid plastics and soft hydrogels find ample applications in engineering and medicine but bear their own disadvantages that limit their broader applications. Bonding these mechanically dissimilar materials may resolve these limitations, preserve their advantages, and offer new opportunities as biointerfaces. Here, a robust adhesion strategy is proposed to integrate highly entangled tough hydrogels and diverse plastics with high interfacial adhesion energy and strength.
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