High-barrier layer flexible packaging film for isolating contents of polymer lithium battery

Abstract

The invention provides a high-barrier layer flexible packaging film for isolating contents of a polymer lithium battery. The high-barrier layer flexible packaging film comprises at least two kinds of films which are combined to form a layer of composite film, wherein the composite film comprises a basic layer, a functional layer and a heat sealing layer; the high-barrier layer flexible packaging film is characterized in that: the basic layer is a copolymer film prepared by combining at least two film base materials of PP (polypropylene), CPP (chlorinated polypropylene or casting polypropylene), PE (polyethylene), PET (poly(ethylene terephthalate)), PA (polyamide) or MXD6 (aromatic polyimide), MPE (elastomer blend), PVDC (polyvinyl dichloride), EVOH (ethylene-vinyl alcohol), PEN (polyethylene naphthalate) and GT, or by complexing pairwise; and a high-barrier water-tolerant modified PVA (poly vinyl alcohol) coating film is coated on the copolymer film base materials. The high-barrier layer flexible packaging film has excellent gas barrier property, remarkably low oxygen permeability, water resistance, corrosion resistance, good high temperature resistance and great barrier property, and resists organic solvents and highly-volatile substances. In the invention, the high-barrier PVA is preferably coated on various base materials to obtain a base layer serving as a high-barrier layer which has great barrier property and excellent performance in resisting gas, water, corrosion, ultraviolet rays and the like.

Description

technical field [0001] The invention relates to a high-barrier flexible packaging film mainly used for gas-blocking, water-blocking, oil-blocking and high-permeability-resistance type composite packaging, especially for blocking electrolyte solution, which is the content of a polymer lithium battery. Internationally, the oxygen transmission rate will be less than 3.8Cm 3 .mm / 24b.m 2 .MPa polymers are called barrier polymers. High barrier standard for high barrier packaging materials: O 2 Permeation rate is 5ml / m 2 , below d, moisture permeability is 2g / m 2 , below d. Background technique [0002] Usually used for flexible packaging to block the contents of polymer lithium batteries, if the adhesive layer is not included, it is mainly a multi-layer co-extruded composite film composed of an outer layer, a barrier layer (middle layer aluminum foil) and a high barrier layer (inner layer) . At present, the production of multilayer composite films at home and abroad usually...

AI Technical Summary

Problems solved by technology

When heat sealing, the heat sealing temperature is (160±15) ℃. The pressure is about 3x105Pa. The time is about 4s. The metal electrode is raised than other places, and the pressure is high. The high temperature softens the material, and the metal electrode is easily pressed to the aluminum layer in the middle of the composite film to cause a short circuit