Additive for improving processability of UHMWPE for battery diaphragm

Abstract

The invention discloses an additive for improving the processability of UHMWPE for a battery diaphragm. The additive comprises HDPE and oleamide, and UHMWPE, HDPE and oleamide are respectively in theratios of 60-99%, 0.75-39.75% and 0.05-0.25%. By using the additive, the problem that UHMWPE is difficult to process is successfully solved, and the diaphragm is high in needle punching strength and free of tears on edges.

Description

technical field [0001] The invention relates to the field of battery materials, in particular to an additive for improving the processability of UHMWPE used in battery diaphragms. Background technique [0002] At present, the market's demand for diaphragms is developing towards thinner, and the requirements for diaphragm thickness are getting thinner and thinner. However, if the diaphragm is too thin, there will be safety problems, and it is necessary to improve the strength of the diaphragm to overcome this shortcoming. The study found that the use of ultra-high molecular weight polyethylene (UHMWPE) exhibited high tensile strength and needle-punched strength under the same process. Because the molecular weight is the basis of the mechanical properties of ultra-high molecular weight fibers, the higher the molecular weight, the smaller the end group concentration, which increases the interaction force of the macromolecular chains. When the external force is applied, the ent...

AI Technical Summary

Problems solved by technology

UHMWPE has high viscosity and strong solubility resistance, so it has poor compatibility with white oil. During the extrusion process, the friction between the melt and the extrusion pipe and the inner wall of the die is relatively large, resulting in the melt being extruded from the die. The surface of the cooled sheet is rough, and there are melt tears on both sides, so that the condition of the film surface cannot meet customer requirements

Images