chemical resistance

It was studied the Processes of ensuring chemical stability (stabilization) of starch nitrate obtained by nitration of starch by two ways: nitric acid and nitric-sulfuric acid mixture. It has been confirmed that, in the first case, starch nitrate has much higher stability due to the absence of low-stable sulfuric acid esters. It is shown that to ensure it in this case, 10 minutes of washing of starch nitrate in  0,19 m3/kg of hot water (95°С) is sufficient.

The influence of talc filler, its content, as well as an additional heat treatment and temperature on the regularities of polylactide materials water-absorption has been researched. Based on the obtained data, the water diffusion coefficient in polylactide materials and the activation energy of the diffusion process were determined. It was found that the process of water absorption by the filled and heat-treated materials based on polylactide proceeds slower and requires more activation energy of the process.

The possibility of using gas-thermal treatment of glass containers with a solution of ammonium salts to increase the water-resistance had shown. To avoid possible cracking of the glass surface, it had suggested using an alcohol suspension or multiple sulfur-containing organic solvents. This greatly improves the chemical resistance of the jar. Therefore on the surface of the treated bottle formed a touch of salt, which has easily washed off with water.

The influence of the polymeric modifier – poly(vinyl chloride) on the chemical stability of polyester composites was investigated. From the results of the research, it is found that equilibrium water absorption for polyester composites is established within 7-14 days. Water absorption of unmodified polyester material is about 1,5%.

Basics and distinctive features of contemporary resource and energy saving technology of powder electrostatic application (POESTA) of vitreous enamel coatings are described. Its technological, economic and ecological advantages over slip enamelling in household appliances manufacture, particularly in Ukraine, are discussed. Synthesis principles of special glass frits with high specific electric resistivity for POESTA and results of investigation concerning development and industrial implementation of ground, direct-on and coloured cover enamels for household appliances are given.