Изучена модификация древесины эфирами фосфористой кислоты в целях уменьшения пожароопасных свойств. Отмечено, что выбор эффективных модификаторов поверхностного слоя является наиболее важной задачей при обеспечении огнезащищенности древесины и что для правильного выбора необходимо знать оптимальные характеристики модификаторов, позволяющие оценивать их эффективность. Определены термодинамические параметры поверхности модифицированной древесины. Обоснованы высокие значения свободной поверхностной энергии при изучении структуры поверхности и поверхностного слоя модифицированной древесины. Показана связь энергетических характеристик поверхности модифицированной древесины, эффективности модификаторов поверхностного слоя, структуры поверхностного слоя и пожароопасных характеристик древесины. На основании полученных данных показана возможность термодинамической оптимизации модификаторов при создании защитных составов.
A study is a modification of wood with phosphorous acid esters in order to reduce fire properties. It is known that phosphorus-containing modifiers are effective flame retardants for wood. Finding the best characteristics to evaluate effectiveness of modifiers is the most rational way to select modifiers, which reduce the fire properties of materials. A significant characteristic for evaluation of effectiveness of surface layer modifiers is a surface energy. To achieve the goal, the task was to study the change of energy characteristics of the modified wood surface and study of thermodynamic optimization of modifiers, which reduce the fire properties of materials. The thermodynamic parameters of the modified wood surface were determined on the basis of which it is possible to select the modifiers of the surface layer for wood. The change of the isothermal-isobaric ensemble of the modified surface was calculated on the basis of the combined equations I and II of the laws of thermodynamics using the “neutral drop” method. The largest values of surface energy are characteristic for wood, which modified by compounds entering into effective chemical interaction with wood. The degree of chemical interaction of the modifiers with wood was studied by the elemental analysis. High values of surface energy are substantiated when studying the structure of the surface and the surface layer of modified wood. The structure of the surface of the wood was studied by electron microscopy. The capillary structure of wood was studied by the method of sorption of water vapor. It is shown that with a high degree of interaction of the modifier with wood, the surface porous layer of wood is strengthened and structured and the pore size is reduced. As a result, there is a reduction in fire hazard and smoke generation ability. The most effective modifier is DEF, which provides the I group of flame retardant efficiency and reduces the smoke generation ability by 6 times. The possibility of the thermodynamic optimization of modifiers to create flame retardants was shown. The most effective modifiers providing high fire resistance of wood are characterized by the most negative values of the isothermal-isobaric ensemble change.
The authors declare that there are no conflicts of interest present.