A method for preparing gamma-polyglutamic acid water-absorbing material

Abstract

The invention discloses a preparation method for a gamma-polyglutamate water absorption material. According to the method, gamma-polyglutamate adopted as a main raw material and caffeic acid-grafted chitosan oligosaccharide adopted as a biodegradable cross linking agent are used for preparing the gamma-polyglutamate hydrogel water absorption material in a water solution. The biodegradable cross linking agent is adopted to replace a common chemical crosslinking agent to prepare hydrogel, a reaction medium is not a toxic organic solvent any more, the safe and nontoxic gamma-polyglutamate is used as the main material, and the water-soluble degradable acrylic acid chitosan oligosaccharide is adopted as the cross linking agent to prepare the gamma-polyglutamate water absorption material. The real safe, nontoxic and biodegradable hydrogel is obtained as both the raw material and the medium are materials harmless to a human body, and the gamma-polyglutamate water absorption material is high in swelling ratio, excellent in mechanical property and improved in degradation property, and can be widely applied to disposable hygiene products, medicine carriers, medical supplies and the like.

Description

technical field [0001] The invention relates to a method for preparing gamma-polyglutamic acid water-absorbing materials, belonging to the field of polymer chemistry. Background technique [0002] γ-polyglutamic acid, referred to as γ-PGA, is a homopolyamino acid that can be fermented and synthesized by a variety of bacteria. It is the main component of some microbial capsules, with a relative molecular mass of 10 5 ~10 6 between. Polyglutamic acid is composed of D-type and L-type glutamic acid linked by γ-amide bond. The polymer structure contains -COOH reactive groups, so it has strong water absorption. [0003] The γ-polyglutamic acid water-absorbing material is a biodegradable hydrogel, which is a kind of functional polymer material with a three-dimensional network, hydrophilic but insoluble in water after being moderately cross-linked. Because of its high swelling property, it is non-toxic Environmental protection and biodegradability have become a research hotspot ...

AI Technical Summary

Problems solved by technology

However, the mechanical properties of the gel prepared by oligochitosan as a cross-linking agent are poor, which may be due to the use of oligochitosan as a cross-linking agent, using the hydroxyl and amino groups in its molecular chain as cross-linking points. The mechanical strength of the obtained hydrogel is obviously far from the strength obtained by chemical crosslinking

[0006] As an improvement, it was reported that acrylic acid grafted chitosan was used as a cross-linking agent. However, it is worth noting that the acrylic acid monomer is highly irritating, and its use as a cross-linking agent will affect the biocompatibility of the subsequent hydrogel.