This paper presents data about the radiation-protective characteristics of multilayer polyimide/lead (PI/Pb) composites for X-ray radiation. Multilayer composites were obtained by collecting lead-filled polyimide track membranes into a sandwich of the required thickness. ( Am) 241 = (E 59.5 keV) and ( Cd) 109 = (E 88 keV) isotopes were used as an X-ray radiation source. To assess the effect of lead filler particle size on the radiation-protective characteristics of a multilayer structure, data are presented on mathematically modeling the passage of 10-88 keV wavelength X-rays with through a composite. The experimental values of the attenuation coefficients of X-ray waves for a multilayer structure are 12-15% higher than the calculated ones. The increase in the attenuation coefficients obtained experimentally, compared with theoretical, is explained by using the proposed multilayer structure with lead particles in the nanoscale range.

The paper presents the possibility of producing polyhedral oligomeric silsesquioxanes (POSS) under hydrothermal conditions in a high-pressure reactor. POSS was prepared by hydrolytic polycondensation of cyclohexyl trichlorosilane under conditions of elevated temperature and pressure. Morphology and structure of the final products were characterized by X-ray diffraction (XRD), thermal analysis (TGA and DTA) in an atmosphere of argon, Fourier transform infrared spectrum (FT-IR) and scanning electron micrograph (SEM). The resulting compound is a nanofibers of a polyhedral oligomeric silsesquioxane. The diameter of the obtained nanofibers is 50 … 150 nm, and the length is from 200 nm to 30 μm.

Special formulas of dry building mortars for construction concrete printing is one of the pertinent areas in the development of innovative construction. The research covers the dry building mortar technology with re-dispersible polymeric powders. The best regime of mixing components with a high-speed paddle wheel agitator was presented. It was shown that only the automation of the construction material production for 3D printing will provide the necessary level of composition stability and property optimization. The work presents some methods of technical control in the production environment. According to the devised functions the technical specifications for the material use were developed. The technical and operational characteristics of the obtained material were researched and the advantages of using polymer-cement concrete in construction 3D printing were identified. On the basis of the obtained results it was established that the specifically designed composition of the mortar reduces stiffening time, has good adhesion characteristics and the necessary plastic strength, this material also delivers impressive performance when it comes to strength and other technical and operational characteristics in comparison with the test mortar.

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