Nylon film composite material for outer film of lithium-ion polymer battery

Abstract

The invention discloses a nylon film composite material for an outer film of a lithium-ion polymer battery, aiming at providing a nylon film composite material which is stable in thermal property, not easy to absorb moisture, puncture-resistant, high in dry-state and low-temperature impact strength, non-deformable in case of absorbing water, good in multi-layer coextrusion compounding compatibility, balanced in flow extension, and capable of realizing no breakage of a corner in case of an impact depth of 3-12 mm or more. The nylon film composite material disclosed by the invention is realized via the following technical scheme: 8-12 wt% of maleic anhydride (MAH), MAH-blended K resin and graft K-MAH grafted POE (polyolefin elastomer) blend material are contained in a nylon filling body; the nylon filling body takes maleic anhydride grafted polyethylene and ethylene propylene terpolymer rubber as interface compatibilizers; a maleic anhydride grafted elastomer carboxylic acid group is reacted with a polyamide end group or a polyamine group in a main chain to form a grafted copolymer; and epoxy resin siloxane hydrolysate is reacted with an amide group molecular-chain amino group to polymerize the composite material with a multi-element interwoven network. According to the composite material disclosed by the invention, the problem of the phenomenon that PA (polyamide) film heat seal is easy to fold, layer and break at a certain corner is solved.

Description

technical field

[0001] The invention relates to a composite nylon material mainly used in polymer lithium ion batteries. Background technique

[0002] Polyamide, a general term for thermoplastic resins containing repeated amide groups -[NHCO]- on the main chain of the molecule, is commonly known as nylon (Nylon), and the English abbreviation is PA. PA is a high crystallinity polymer, which will crystallize immediately after stretching, so it cannot be stretched continuously. It must be produced by adding special additives in the traditional two-step production line, and the price is expensive. Since nylon film is a product that is very easy to absorb moisture, it will have adverse effects on the packaging of the polymer lithium-ion battery when it absorbs moisture, such as insufficient composite strength and foaming caused by the water film on the surface. Although it meets different special requirements, it is widely used as a substitute for traditional materials such as m...