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The sands of various dispersion&origin can watch as basic filler for tonnage build & industrial compounds. The work is devoted to the urgent topic of obtaining cheapened epoxy materials with a high content of natural and building sand. In the case of composite optimization, it is possible to obtain valuable competitive multitonnage composites, moreover, while maintaining the original performance properties or even improving them. In our work, the sand from Ukrainian mines & rivers were used. It is tree types of sand: A) “Quarry” – from industrial carrier in nord of Ukraina; B) “Bottom” – from bottom of big river (Desna); C) “Fabric” – industrial sand TM Stark, Ukraina. A number of practically important properties of composite materials based on epoxy resin and sand of various types and dispersions (50 wt%) have been established. It is shown that 50 wt% of all used sands leads to essential increasing of AbrasiveResistance and SwellingResistance, and microhardness. At same time, 50%-filling decreases investigated strength parameters (to compression & to bending). Is important that sands let reach a high esthetic characteristics of composites: in this simple method can obtain wood-, stone-, honey-like composite materials for building, design & décor. The prospects for the implementation of these results are quite wide, since they cover both large-tonnage construction and repair, innovative industries, as well as small repair segments that are now developed (car service, museum restoration) and handmade. At the same time, this work only opens up these prospects and can become the basis for further scientific and practical research

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This paper reports the results of studying epoxy compositions with gypsum taken in the form of dispersed powders in the original and water-hardened form. The exact pattern has been shown in the way the introduction of a gypsum additive in the amount of 50 % by weight affects the strength, chemical stability, and morphology of the composites. Under conventional heat treatment (60-110 °C) of the hardened composites, the maximum stress at compression σ m and the elasticity module at compression Е с , as well as wear resistance, decrease after the introduction of gypsums (of both types). At the same time, after a hard (destructive) heating at 250-260 °C, the elasticity module Ес of the hardened composites increases. The maximum stress at compression σ m is also increased. The same applies to the wear resistance, which grows especially noticeably after 250 °C. The micro-hardness after filling is prone to increase but the fragility of epoxy-gypsum composites does not make it possible to measure it when a punch (a steel hemisphere) penetrates it deeper than 20 μm. However, after the heat treatment at 250-260 °C, the unfilled polymer, on the contrary, is embrittled while the filled ones are plasticized, thus showing a high micro-hardness at significant (30-50 μm) immersion. The composites with gypsum, in contrast to the unfilled ones, do not disintegrate in acetone and retain integrity at any aging duration (up to 75 days and beyond). In this case, the original gypsum produces a composite with less swelling in acetone than the hardened gypsum. Based on the data from atomic-strength microscopy (ASM) microscopy, the morphologies of the non-filled composite, the composites with the hardened gypsum and original gypsum are different. The original gypsum forms a composite with a more pronounced (possibly crystalline) filler structure; the morphology for the hardened composite reflects the distribution of inert particles; for the unfilled composite (H-composite), only pores are visible against the background of a relatively smooth relief

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