Humidity-control composite film, and preparation method and application thereof

Abstract

The invention relates to a humidity-control composite film, and a preparation method and application thereof. The humidity-control composite film comprises a base layer and an additional layer, and the additional layer is located on one side of the base layer. The base layer is a porous film, and the additional layer comprises a multi-element hydroxyl polymer and an optional antibacterial agent; and the surface of the additional layer is a surface modification layer grafted with 2-acrylamido-2-methylpropanesulfonic acid, and the surface modification layer is grafted to the surface of the additional layer through a microwave branching reaction. The humidity-control composite film has the intelligent humidity control capability, keeps the humidity of fruits and vegetables when the relative humidity is relatively low, increases the moisture permeability when the relative humidity is relatively high so as to prevent the fruits and vegetables from dew formation and ulceration, has the oxygen barrier property, and can be used for a fruit and vegetable box with a fresh-keeping function and a refrigerator with the fresh-keeping fruit and vegetable box.

Description

technical field [0001] The invention relates to the field of functional films, in particular to a humidity control composite film and its preparation method and application. Background technique [0002] Fruits and vegetables are important foods for human beings, and they are the main sources of basic nutrients (vitamins, minerals, complex carbohydrates, etc.). With the improvement of people's living standards, the requirements for the freshness of fresh fruits and vegetables are getting higher and higher. Fruits and vegetables can continue to carry out life activities such as respiration and transpiration after harvesting, and water loss and nutrient consumption will occur during storage. For every 10°C increase in temperature, the respiratory intensity of fruits and vegetables doubles. The way to keep fruits and vegetables fresh at home is to store fruits and vegetables in the refrigerator to slow down the respiration of fruits and vegetables. In fruits and vegetables, ...

AI Technical Summary

Problems solved by technology

The temperature-sensitive and moisture-permeable membrane is prone to condensation on the surface of the membrane under high humidity and low temperature; the silicon filter membrane has a moisturizing function, but the moisture permeability cannot be changed with humidity; The performance meets the requirements, but the preparation process is not environmentally friendly, the process is complicated, and there may be problems with excessive chlorine content in the processing process

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