Starch/PVA composite antibacterial preservative film and preparation method thereof

Abstract

The invention provides a starch / PVA composite antibacterial preservative film and a preparation method thereof, a formula of an existing starch / PVA-based preservative film is optimized, and the improved composite antibacterial preservative film is prepared from the following raw materials in parts by weight: 100 parts of PVA, 20-40 parts of starch, 10-20 parts of chitosan, 5-20 parts of a plasticizer, 0.5-2 parts of a cross-linking agent, 0.5-2 parts of a surfactant, 1-3 parts of a defoaming agent and 200-300 parts of water. Specific process parameters such as raw material mixing and adding sequence, temperature, reaction time and the like in the preparation process are limited, so that the preservative film can better adapt to the characteristics of the formula, the effects of various components are maximized, vegetables and fruits in the preservative film can be always kept in a low-humidity environment, and under the action of PVA (polyvinyl alcohol), chitosan and the like, the preservative film has a good preservation effect on the vegetables and the fruits. Propagation of microorganisms in the film is effectively inhibited, and the composite preservative film which is degradable, excellent in antibacterial performance and good in mechanical property is prepared.

Description

technical field [0001] The invention relates to the technical field of polymer materials, in particular to a starch / PVA composite antibacterial fresh-keeping film and a preparation method thereof. Background technique [0002] Plastic wrap is a kind of plastic packaging product widely used in households to preserve food such as vegetables and fruits. Its main function is to prevent dust and bacteria from polluting food, and at the same time extend the shelf life of food by isolating the air. Most of the plastic wraps currently on the market are made of vinyl materials, such as PE, PVC, PVDC, etc. The common problem of these materials is that they are difficult to degrade, which will further aggravate white pollution and damage the environment. Antibacterial plastic wrap is to add antibacterial agents to the existing plastic wrap, such as typical silver-based antibacterial agents, titanium dioxide, etc. But this also has the problem of being difficult to degrade. [0003] I...

AI Technical Summary

Problems solved by technology

Chinese patent CN109422983A has proposed a kind of method that starch, cationic starch, PVA constitute skeleton structure, add cross-linking agent, plasticizer, defoaming agent, film-forming auxiliary agent to make antibacterial safe film, have introduced these two kinds of starch and PVA The degradable material solves the problem that vinyl is difficult to degrade in antibacterial and fresh preservation, but the addition of starch will inevitably affect the mechanical properties of the product. Therefore, there is still room and necessity for this technology to continue to improve.

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