A kind of heat-shrinkable film and its preparation method and application

Abstract

The invention provides a high-performance heat-shrinkable film, which has the advantages of low shrinkage temperature, fast shrinkage speed, low water vapor transmission rate, high transparency and the like. The heat-shrinkable film is prepared by a three-layer co-extrusion blown film method, including an outer layer, a middle layer, and an inner layer; the mass ratio of the outer layer: the middle layer: the inner layer is 1-3:1-3:1-3 ; The outer layer includes high-pressure low-density polyethylene, ethylene-vinyl acetate copolymer, anti-adhesive masterbatch, smooth masterbatch and antistatic masterbatch; the middle layer includes ethylene-vinyl acetate copolymer and propylene-based elastomer; The inner layer includes high-pressure low-density polyethylene, metallocene low-density polyethylene, propylene-based elastomer, anti-adhesive masterbatch, smooth masterbatch, and antistatic masterbatch. The heat shrinkable film of the present invention improves the tensile strength and elastic modulus, and effectively reduces the rate of bag breakage; the heat shrinkage rate is as high as 75% after being treated at 130°C for 20 seconds, the light transmittance is greater than 90%, and the haze and gloss are very high Big improvement.

Description

technical field [0001] The invention belongs to the technical field of polymer materials for packaging, and relates to a heat-shrinkable film, in particular to a heat-shrinkable film with good shrinkage efficiency and high transparency, a preparation method and an application thereof. Background technique [0002] With the increase of national environmental protection and energy saving efforts, some products packed in cartons are increasingly replaced by plastic packaging, and the increase in the consumption of plastic packaging products will definitely promote the technological progress and rapid development of the plastic packaging machinery industry. The economic macro and micro conditions are getting better, and social demand will show a steady growth, which is expected to stimulate the growth of plastic product consumption. In order to meet the requirements of the new era, plastic packaging materials are also required to meet the increasing packaging quality and efficie...

AI Technical Summary

Problems solved by technology

However, there are still many problems in the use of these two types of shrink films. For example, POF shrink film has poor toughness and is easy to break the package; ordinary PE shrink film has high shrinkage temperature, slow shrinkage speed, and low efficiency. If the outer layer of the package is PE The film is easy to melt and stick when passing through the drying tunnel, and its transparency is poor. It is impossible to scan and identify the packaged product label. It needs to be labeled on the outside of the film, which increases the process and reduces the efficiency.

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