Preparation method of supercritical micro-foaming high-light plastic and plastic-based composite material and supercritical micro-foaming high-light plastic or plastic-based composite material prepared through preparation method

Abstract

The invention relates to the technical field of preparation of high polymer materials and provides a preparation method of supercritical micro-foaming high-light plastic and a plastic-based composite material and the supercritical micro-foaming high-light plastic or the plastic-based composite material prepared through the preparation method for solving the problem that the bubble hole size and bubble density of plastic and a plastic-based composite material thereof are difficult to control. The method comprises the following steps that 1, a hot melt adhesive is prepared, particularly, the plastic or the plastic-based composite material is heated to be molten, and the hot melt adhesive is formed under the shearing effect of a screw rod; 2, a single-phase melt is prepared, particularly, supercritical foaming gas is injected into the end of the screw rod to be mixed into the hot melt adhesive obtained in the step 1, and the single-phase melt is formed; 3, injection molding is carried out, and particularly high-temperature steam is adopted for rapidly injecting the single-phase melt obtained in the step 2 into an injection model; and 4, cooling molding is carried out, particularly, a condensing agent is adopted for rapidly reducing the temperature of the injection model in the step 3, and therefore the high-light plastic or the plastic-based composite material with high-density micro holes inside is obtained.

Description

technical field [0001] The invention relates to the technical field of polymer material preparation, and specifically provides a method for preparing supercritical micro-foamed high-gloss plastics and plastic-based composite materials and the plastic or plastic-based composite materials. Background technique [0002] There are many plastic molding methods, such as extrusion, injection molding, etc. The foaming methods include chemical foaming method and physical foaming method. Chemical foaming is to add chemical foaming agents such as azo compounds, sulfonyl hydrazine compounds, nitroso compounds and sodium bicarbonate to the raw materials. The cell size and density are uneven, difficult to control, and do not meet environmental protection requirements. Physical foaming, such as using supercritical nitrogen or carbon dioxide, can control the size of the cells to the micron level, and the density can reach millions of cells per cubic centimeter. However, the surface of the ...

AI Technical Summary

Problems solved by technology

However, the surface of the material obtained by the above method is prone to flow marks, air marks, foaming and roughness, etc., and the surface finish is not high

Some scholars and patents have proposed methods such as pressure holding, segmented gas injection, and surface filming to improve surface brightness, but the density and uniformity of bubbles are reduced, the control is difficult, and the procedure is complicated and costly.

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