METHOD FOR PRODUCING GRADIENT POLYMER COMPOSITE BY 3D PRINTING (EMBODIMENTS) AND GRADIENT POLYMER COMPOSITE OBTAINED BY THIS METHOD Russian patent published in 2024 - IPC B29C64/112 B29C64/118 B33Y10/00 B33Y70/10 B33Y80/00 

FIELD: additive manufacturing.

SUBSTANCE: group of inventions relates to the variants for the production of a gradient polymer composite by 3D printing and to a gradient polymer composite obtained by these methods. One of the variants of the method is carried out by creating a 3D model of the required part, processing the 3D model of the required part, obtaining a series of 2D sections - 3D printing layers. Next, requirements are developed for the mechanical, abrasive, frictional or antifriction and other volumetric and surface properties of the part. Based on these requirements, an organic polymer is selected from the following range: acrylonitrile-butadiene styrene plastic, polylactide, polyethylene, polypropylene, polyvinyl chloride, polystyrene, polyformaldehyde, polycarbonate, not less than one filler is selected, then the information about the filler distribution gradient is translated into a series of 2D material composition data in accordance with the requirements of the part structure gradient. Moreover, an organic polymer is additionally selected from the series: polyphenylene sulphide, polysulfone, polyimide, polyetheretherketone, polycaprolactone, thermoplastic polyurethane, polyetherimide, and the filler is selected among inorganic, organic or short fibres, or several fillers, and the distribution gradient of the filler, or fillers, over the volume of the part is determined. After converting information about the filler distribution gradient into a series of 2D data on the composition of the material in accordance with the requirements of the component structure gradient, preliminary mixing of the filler powder with the selected organic polymer is carried out. For this purpose in a twin-screw extruder at a temperature of 190-410°C a concentrate is prepared - a mixture with a maximum concentration of the required filler in the required organic polymer, while the concentration of the filler in the organic polymer is selected in the range from 5 to 65 wt.% depending on the type of organic polymer and filler. Next, at least one type of the resulting concentrate in the form of granules is loaded into the hoppers of the 3D printing device, as well as, if necessary, an organic polymer in the form of granules without filler. Then, to create a gradient of filler distribution, granules of at least one type of concentrate in the required ratio among themselves and, if necessary, organic polymer granules are fed from the hopper to the mixer of the 3D printing device in the required ratio within the range, parts by weight: concentrate granules : organic polymer granules = from 0:100 to 100:0 according to the settings, mixed and melted by heating to a temperature of 190-410°C, then the melt is pressed into the print head. Next, the layers are printed line by line and the required part is formed by melting FGF granules until the gradient polymer composite of the part is completely formed.

EFFECT: expanding the range of organic polymers, expanding the range of fillers according to the nature of the materials and the shape of the particles, improving the mixing of fillers and organic polymers and combining a gradient of two or more fillers in the finished part.

3 cl, 2 dwg, 60 ex