A hybrid coating made of poly (methyl methacrylate) with SiO₂-TiO₂ particles (PMMA/SiO₂-TiO₂) has been developed for use as a coating on nanosatellites, evaluating its resistance to high vacuum by quantifying its weight loss. The coating was applied on an Al 7075 aluminum substrate used for the aerospace sector. PMMA/SiO₂-TiO₂ hybrid coatings were prepared using sol-gel reaction in situ assisted with sonochemistry. The SiO₂ particles and TiO₂ (50:50% wt. of rutile/anatase) particles by tetraethyl orthosilicate (TEOS), and Titanium (IV) Isopropoxide (TIPO). Radical polymerization of methyl methacrylate (MMA) monomer was conducted with (3-mercaptopropyl) trimethoxy silane (3-MPTS) used as a coupling molecular agent, and benzoyl peroxide as a catalyst. The coatings obtained have a thickness of 20 μm which were deposited by blade coating technique on the substrate, obtaining homogeneous and defect-free coatings. Adhesion and hardness were measured using ASTM standards required for this sector. To evaluate its resistance to ultra-high vacuum, it was done as close as possible to the ASTM E-595 norm [1], where it indicates that the coatings must be evaluated at vacuum conditions of 10⁻⁵ Torr and 125°C for a period of 24 hours. The coatings were evaluated before and after the test by spectroscopy analysis to determine a possible degradation in the chemical structure. The resulting weight loss not exceeding 0.02%, and the addition of Ti-O-Si particles led to an increase in chemical stability under vacuum conditions without affecting the chemical structure of the highly cross-linked PMMA/Ti-O-Si matrix, which was monitored by FTIR and Raman spectroscopy.

In recent years, space exploration has become increasingly accessible to a diverse array of countries, facilitated in part by CubeSat nanosatellites. These versatile nanosatellites find applications in a wide spectrum of fields, from forest fire detection and meteorological observation to communication systems, particle analysis, and hot spot identification. This article delves into the outcomes of a comprehensive thermal analysis conducted on the IXAYA nanosatellite. The primary mission of this nanosatellite is to identify hot spots in the vicinity of Mexico City. The thermal analysis process entails a meticulous review of each subsystem along with the associated boundary conditions. This study commences with the definition of an optical payload and a thorough assessment of subsystem requirements. Subsequently, we calculate both external and internal thermal loads. With these foundational data points, we progress to ascertain the temperature distribution across the entirety of the satellite, ensuring that all constituent elements remain within their designated operational temperature ranges. In the closing section, we present our findings and conclusions.

Anti-corrosive evaluation of a hybrid polymethylmethacrylate (PMMA) with silica particles (SiO₂) is presented, the hybrid (PMMA-SiO₂) was synthetized in situ by sol-gel process. The SiO₂ particles were embedded into to matrix PMMA at different concentrations. The hybrid structure of the coatings was characterized and observed with Fourier Transform Infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The deposition of the hybrid in aluminum 7075-T6 (Al7075) substrates was made with the blade coating technique, measuring wet and dry film thickness. For the preparation of the hybrid, PMMA was used without any type of curing, which allowed us to save resources. All tests were performed according to American Society for Testing and Materials (ASTM international) standards. The incorporation of SiO₂ to concentrations significantly improved the mechanical and anti-corrosive results. PMMA-SiO₂ coating, once deposited on the surface of Al7075 plates, has been tested inside a salt fog chamber (CNS) operated under accelerated conditions. They were improved up to 920 h its corrosion resistance. The abrasion tests had an increase of 50%, its hardness up to 4H and the wear index improved by 50% compared with the hybrids with minor SiO₂ concentration, which shows that a higher concentration of SiO₂ particles has a higher performance of the coating.