Preparation method and application of double-network polyvinyl alcohol-polyacrylic acid hydrogel

Abstract

The invention discloses a preparation method of dual-network polyvinyl alcohol-polyacrylic acid hydrogel. The preparation method comprises the following specific steps: (1) adding polyvinyl alcohol into deionized water according to a mass ratio of polyvinyl alcohol to deionized water of 1: (9-13), and conducting heating and stirring at 90-100 DEG C for 0.8 hour or more to obtain a transparent solution; (2) adding acrylic acid, a cross-linking agent and an initiator into the solution obtained in the step (1), and continuing stirring at 40-50 DEG C for 25-50 minutes to obtain a uniform mixed solution; (3) pouring the mixed solution obtained in the step (2) into a polytetrafluoroethylene mold, putting the polytetrafluoroethylene mold into a drying oven with a temperature of 60-70 DEG C for 3-4 hours, polymerizing acrylic acid into polyacrylic acid, and allowing polyacrylic acid to form interpenetrating network hydrogel with polyvinyl alcohol; (4) freezing the obtained hydrogel for 8-16 hours, then freeze-drying the hydrogel for 8-16 hours, and then conducting soaking and swelling with deionized water for 8-16 hours; and (5) repeating the step (4) 5-8 times. The invention also provides application of the hydrogel. In the deformation process of the hydrogel, a large amount of energy is easier to dissipate, crack propagation is avoided, and the toughness and strength of a hydrogel material are enhanced.

Description

technical field [0001] The invention relates to the field of polymer materials, in particular to a method for preparing a high-strength and high-toughness hydrogel. Background technique [0002] Hydrogels are usually a colloidal structure of polymer chains characterized by three-dimensional cross-linked networks obtained from the polymerization of hydrophilic polymers. These three-dimensional network structures endow hydrogels with good hydrophilicity and biocompatibility. Due to these properties, hydrogels have been widely used in controlled drug delivery systems, artificial biomedical scaffolds, cosmetics, and soft actuators. [0003] However, the toughness and strength of conventional single-network hydrogels are usually poor, which limits the practical applications of hydrogels. Dual network hydrogels are made of two interpenetrating hydrophilic networks with opposite structures and mechanical properties. One is a highly cross-linked brittle network with a low concentr...

AI Technical Summary

Problems solved by technology

During deformation, this highly contrasting double-network structure leads to the internal rupture of the first network, thereby dissipating a large amount of energy without crack propagation

However, the mechanical properties of conventional double network hydrogels are still not satisfactory for our practical applications

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