A device has been developed that allows measuring the edge angle of wetting of flat surfaces with liquid. The device is characterized by simplicity of implementation, low cost, allows you to simplify the measurement process and eliminate errors associated with the individual characteristics of the observer. As an example, by determining the wetting edge angle, the hydrophilicity (hydrophobicity) of surfaces – fluoroplast, steel and steel with a separation coating based on the composition of Penta-100 when they are wetted with water. The dependence of the wetting edge angle of the initial composition of Penta-100 in the liquid state on the viability of the solution has been studied. The correlation of the marginal wetting angle of the Penta-100 solution with the porosity of the formed coating with the surface is shown. The proposed device can be used in educational and industrial laboratories for rapid assessment of the condition of various surfaces.

Keywords: surface, wetting edge angle, water, coating

The impact of the alkali NaOH on the structure and morphology of cellulose has been considered. Using X-ray spectroscopic microanalysis and electron microscopy, it has been determined that treatment of wood cellulose with aqueous solutions of NaOH allows to reduce the content of lignin in cellulose and significantly improve the topography of the fibers. A comparative analysis of alkali cellulose samples was conducted, obtained during treatment with NaOH solutions of 13.7% and 12.3% concentration for a process duration of 5.5 hours, at a temperature of 124 °C. It has been established that at the considered concentrations of NaOH, approximately ~75% and ~50% of lignin is removed from the original cellulose, respectively. The results of infrared spectroscopy indicate an increase in the amorphization of alkali cellulose. Alkali cellulose, formed at a NaOH concentration of 13.7%, exhibits superior morphological uniformity and a lower lignin content.

Keywords: wood cellulose, chemical treatment, alkalinity, lignin, X-ray spectral microanalysis, electron microscopy