Method for preparing high-strength anti-retraction microporous expandable polyethylene (EPE) beads

Abstract

According to the invention, a conventional nucleating agent suitable for regulating and controlling the crystallization behavior of polypropylene is applied to control the crystallization behavior ofpolyethylene, and the invention discloses a method for controlling assembling and preparing microporous expandable polyethylene beads by using different crystallization behaviors. 20-95 parts of linear low-density polyethylene adopted as matrix resin; 10-45 parts of high-density polyethylene or atactic polypropylene (the melting point is 130-150 DEG C); 0.05-5 parts of alpha-crystal nucleating agents comprising an inorganic nucleating agent with an alpha-crystal nucleating function, aromatic carboxylate, sorbitol and the like; and 1-15 parts of an auxiliary agent are utilized in the method. Extruding and granulating steps are performed by adopting a double-screw extruder. During production, an intermittent method is adopted; different crystallization nucleating agents are used for coordinating layer-by-layer assembling crystallization, rigidity increasing changes generated by the polypropylene alpha crystallization nucleating agents are flexibly combined with the crystallization speed,the size of crystal particles and the growth and solidification process of foam holes of a foam material, and the microporous expandable polyethylene beads good in performance and resistant to retraction are prepared.

Description

technical field

[0001] A method for high-strength shrinkage-resistant microporous polyethylene foam beads (EPE) The invention relates to polyethylene foam beads and belongs to the field of polymer modification processing. The present invention adopts intermittent or continuous physical foaming method, utilizes different crystallization nucleating agents to coordinate layer-by-layer assembly crystallization, and combines the rigidity change produced by the polypropylene α crystallization nucleating agent, the speed of crystallization, the size of crystallization particles and the foaming The growth and curing process of the material cells is flexibly combined, and the cell structure of the produced polyethylene expanded beads (EPE) is evenly distributed, and the cell size of the prepared materials is between 20 and 50 μm. Cellular polyethylene foam beads. Background technique

[0002] Low-density polyethylene foam has excellent physical, chemical and mechanical properties. ...