Physical foaming method of high polymer material and foaming product

Abstract

The invention relates to a physical foaming method of a high polymer material and a foaming product. The physical foaming method of the high polymer material comprises the steps that 1, a thermoplastic elastomer or a polyolefin material is prepared into special-shaped parison by using an injection molding machine, an extruding machine or a molding press; 2, the polyolefin parison is heated to produce cross-linking reaction, and the cross-linked polyolefin parison is obtained; 2, the thermoplastic elastomer parison or the cross-linked polyolefin parison is subjected to high-pressure infiltration in a pressure kettle with a supercritical fluid, then pressure relief is performed to normal pressure, and the supercritical fluid infiltrated parison is obtained; 4, the supercritical fluid infiltrated parison is arranged in a finished product mold, and in-mold foaming is performed according to the ratio of 1:1 to obtain the finished product foaming product. The supercritical fluid is utilizedas a physical foaming agent, and the low-specific-gravity, environment-friendly and non-toxic foaming material having excellent elasticity is obtained through a simple in-mold foaming process.

Description

technical field [0001] The invention relates to the field of polymer materials, in particular to a physical foaming method for polymer materials and foamed products. Background technique [0002] The foaming process is one of the commonly used processes for making low specific gravity materials. The foaming process can be divided into chemical foaming process and physical foaming process according to the foaming agent used. The traditional production of low specific gravity polyolefin chemical foaming materials requires the use of chemical foaming agents, which usually have the following disadvantages: they do not meet environmental protection requirements; there are harmful substances in the decomposition substances of foaming agents, which do not comply with relevant safety regulations. Traditionally, the main methods of making polyolefin physical foaming materials are gas-assisted injection molding, extrusion molding, etc., using alkane gases, low-volatile point compound...

AI Technical Summary

Problems solved by technology

The traditional production of low specific gravity polyolefin chemical foaming materials requires the use of chemical foaming agents, which usually have the following disadvantages: they do not meet environmental protection requirements; there are harmful substances in the decomposition substances of foaming agents, which do not comply with relevant safety regulations

[0003] The above method of making special-shaped physical foaming materials usually has the following disadvantages: high specific gravity (about 0.4 or more), low elasticity, poor touch, and air marks on the surface that are not smooth enough, so it is not suitable for making shoe materials and those with cushioning effects. Products such as floor mats or sports equipment

In addition, the traditional production of polyolefin physical or chemical foaming products is foamed outside the mold, and then placed in the finished mold for secondary processing, the process is cumbersome and time-consuming