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The report describes the features of physical and mechanical properties and absorption capacity of hydrogels based on highly esterified pectin. Experimental data showed the correlation between these values. Also, an attempt is made to explain the obtained dependencies via the hydrogel morphology and the mechanism of its formation.

Organic-inorganic hydrophilic composites based on sodium polyacrylate (PAANa) and poly-N-(2-aminoethyl)-3-aminopropyltrimethoxysilane (PAPTMS) showed the improved swelling capacity at incorporation of PAPTMS. Changing of non-Fickian to Super case II swelling behaviour is observed at 20 wt % PAPTMS content. Enhancing of thermal stability and heat-resistance index of composite hydrogels compared to PAA is shown.

The paper presents the results of the study of copolymerization of 2-hydroxyethylmethacrylate (HEMA) with polyvinylpyrrolidone (PVP) under the action of two-component initiation systems of iron (II) sulfate/radical type initiator. The influence of the nature of the radical initiator (In) in the FeSO4/In system on the behavior of the polymerization of HEMA/PVP compositions, structural parameters of the polymer matrix network and properties of hydrogels based on pHEMA-gr-PVP copolymers were established.

The formation of the hydrogel polymer matrix duringthe gelatin cross-linking with dioxirane derivatives of polyoxyethylene glycolswere studied.The optimal conditions for their synthesis were determined. The characteristics of the hydrogel (swelling in different media, mechanical properties at different temperatures) were obtained depending on the type of dioxirane derivative and prepolymer ratio. The possibility of introducing several drugs into hydrogels was established and the release of these drugs was found to be prolonged.

The method of the composite hydrogel membranes synthesis based on the 2-hydroxyethyl methacrylate (HEMA) and polyvinylpyrrolidone (PVP) with simultaneous modification in the volume by the mixture of polyamide-6 (PA-6) and PVP solution with varying the concentration of the reaction mixture in the water has been described in this study. The influence of the water content in the reaction composition on the physical mechanical properties and water absorption of the obtained membranes has been investigated. o

This research report facile approach on dispersion of cellulose fiber extracted from oil palm frond waste in a “green-solution” prepared by using urea and sodium hydroxide while the polymerization is carried out using microwave to form hydrogels. Effects of adding cellulose was determined by comparing the swelling degree between 0% and 2% cellulose hydrogel. Results showed that swelling ratio enhanced by the presence of cellulose. SEM images exposed that hydrogel with cellulose has rough surface compared to the hydrogels without cellulose.

The various samples of pectins with degrees of esterification of 40-70% in the work were obtained using pectin with degree of esterification of 81.5%. It was shown that the determining factor for successful formation of hydrogel plates is the degree of esterification of polysaccharide. It was established that hydrogel plates obtained by the method of structuring of calcium salts are formed only on the basis of pectin with the degree of esterification less than 70%.

Modern hydrogel healing therapies for damaged human skin, must perform a number of functions which are inherent for the skin: 1) preservation of thermal and water balance; 2) ensuring of oxygen penetration; 3) providing transportation of substances necessary for the functioning of the organism; 4) protection from mechanical damage. When using hydrogel coatings on damaged areas of the skin, they must perform, an additional function - prolonged delivery to the wound of therapeutic agents of various nature.

Polymer hydrogels, which are close to biological cells in their physical state, have proven to be effective in medicine and pharmacy. However, in practice the wide usage of hydrogel products is limited by their low mechanical strength, even though generally the application of hydrogels has a great potential . Recently, the interest to the polymer hydrogel materials, that have high mechanical strength in a hydrated state along with the hydrophilic and diffusion-transport properties, has increased.