Optical properties and radiation stability of polypropylene modified with MgO nanoparticles

Polymer composite materials are widely used in spacecraft and stations in thermal control coatings, as sealants, seals, thermal insulation, as well as in many other structures and products. The main characteristic of such materials is the stability of properties and performance characteristics to the action of space factors, among which various types of radiation are the main damaging ones. Therefore, it is relevant to study the influence of electron, proton, solar spectrum quanta on the change in optical, electrical, mechanical, and other properties of polymer composite materials. This paper presents the results of a investigation of the optical properties and radiation stability of nanocomposites based on polypropylene modified by the solid state method with MgO nanoparticles in the concentration range of 1–5 mass.%. Diffuse reflectance spectra were recorded in a vacuum of 2·10-6 Torr before and after electron irradiation (in situ, E = 30 keV, H = 2·1016 cm-2). The analysis of the nature of the absorption bands recorded in the diffuse reflection spectra, which are due to the formation of free radicals: – С3Н5 –, – С3Н6 –, – C4H6 –, – C4H7 –, – C4H8–, – C4H12 –, – C5H7 –, – C5H10 –, was performed. The optimal value of the concentration of nanoparticles was established, equal to 2 mass.%, at which the area of the integral absorption band at 360 nm after irradiation decreased by 3,35 times, its intensity at the maximum by 3,88 times compared with unmodified polypropylene.