В настоящее время перед отечественным производителем древесных композиционных материалов стоят задачи по увеличению объемов производства, повышению качества и конкурентоспособности, снижению токсичности выпускаемой продукции. Решение этих задач основано на разработке новых и совершенствовании имеющихся технологий современного производства клеёв и композиционных материалов на их основе. Цель исследования – повышение эффективности производства фанеры путём применения клеев на основе порошкообразных термореактивных полимеров поликонденсационного типа. Для достижения поставленной цели в работе необходимо исследовать влияние наполнителя на свойства клеевой композиции и готовой продукции. Исходными компонентами для проведения экспериментов являлись порошковая фенолоформальдегидная смола и аэросил технический. Установлено, что введение аэросила технического в клеящие составы на основе поликонденсационной порошковой фенолоформальдегидной смолы СФЖ-3013 увеличивает прочность фанеры, также с увеличением количества наполнителя уменьшается содержание свободных продуктов в смоле: содержание свободных фенола и формальдегида уменьшается до 0,05 – 0,06% и 0,02 – 0,03% соответственно. Предполагается, что при горячем способе склеивания происходит гелеобразование, частицы аэросила образуют разветвленные цепочки ~Si-O-Si~, которые целиком пронизывают объем клея, этот процесс сопровождается связыванием формальдегида в процессе структурирования. Полученные результаты исследований могут быть использованы в работе специалистов деревообрабатывающих производств при управлении технологическими процессами склеивания. Разработанные составы клеевой композиции на основе фенолоформальдегидных смол, модифицированных (наполненных) техническим аэросилом позволяют сократить расход клеевых материалов; повысить прочность и качество склеиваемой продукции; ускорить процесс отверждения связующего; сократить продолжительность склеивания; снизить энергозатраты путем уменьшения времени склеивания; уменьшить себестоимость клея, за счёт замещения основных компонентов наполнителем. At present, the domestic manufacturer of wood composite materials is faced with tasks to increase production volumes, improve quality and competitiveness, and reduce the toxicity of manufactured products. The solution to these problems is based on the development of new and improvement of existing technologies for the modern production of adhesives and composite materials based on them. The purpose of the study is to increase the efficiency of plywood production by using adhesives based on powdered thermoset polymers of the polycondensation type. To achieve this goal in the work, it is necessary to study the effect of the filler on the properties of the adhesive composition and finished products. The initial components for the experiments were powder phenol-formaldehyde resin and technical aerosil. It was found that the introduction of technical aerosil in adhesives based on polycondensation powder phenol-formaldehyde resin SFZh-3013 increases the strength of plywood, as the amount of filler increases, the content of free products in the resin decreases: the content of free phenol and formaldehyde decreases to 0.05 – 0.06% and 0.02 – 0.03%, respectively. It is assumed that during the hot bonding method, gel formation occurs, so that aerosil particles form branched chains ~ Si-O-Si ~ that completely penetrate the glue volume, this process is accompanied by formaldehyde bonding during structuring. The obtained research results can be used in the work of specialists in woodworking industries in the management of gluing processes. The developed compositions of the adhesive composition based on phenol-formaldehyde resins modified (filled) with technical aerosil allow you to: reduce the consumption of adhesive materials; to increase the strength and quality of glued products; speed up the curing process of the binder; shorten bonding time; reduce energy costs by reducing the bonding time; reduce the cost of glue, due to the replacement of the main components with filler.

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The main drivers of competition among the products made with the use of adhesive compositions are the toxicity of finished products, the consumption of raw materials and energy resources, the duration of the main technological operations. These drivers can be controlled by using adhesives with different fillings and/or modifications. Adhesives based on phenol-formaldehyde and melamine-urea-formaldehyde resins are used to produce plywood with increased water resistance. Apart from resins, adhesives usually contain hardeners, fillers, and modifiers that affect the properties of the finished product. Technical aerosol is one of the modifiers of synthetic resins with a wide range of action. Aerosil is characterized by three types of interaction: physical adsorption, chemical adsorption (formation of hydrogen bridges by silanol groups), and chemical reactions on the surface layer. The chemical composition of aerosil was analyzed. Technical aluminum fluoride (AlF3) is of particular interest. It can interact with alkali metal fluorides with the formation of complex compounds that improve polymer structuring. The acids that make up aerosil reduce the pH to 2.0–3.5, so they can be catalysts for the curing process of melamine-urea-formaldehyde resins. The effect of technical aerosil on the properties of adhesive systems based on phenol-formaldehyde and melamine-ureaformaldehyde resins has been studied. Viscosity, curing time, and wetting ability of adhesive compositions were determined. The obtained results indicate the possibility of using this modifier in the composition of phenol-formaldehyde and melamine-urea-formaldehyde resins up to 15 pts. wt. The nature of the aerosil action on adhesive compositions was determined using IR spectroscopy. Analysis of the results showed that aerosil promotes deep structure formation of the polymer by increasing the molecular weight of the molecules. These bonds make it possible to form a more structured polymer with bound formaldehyde. Studies of the effect of aerosil on the properties of finished products were carried out. At the same time, an increase in performance indicators was found: the strength of adhesion increases, the toxicity of plywood decreases. The results of experiments on the effect of technical aerosil, taking into account the reduction of bonding time can be applied in the development of technological processes for obtaining plywood of high water resistance. For citation: Sokolova E.G., Rusakov D.S., Varankina G.S., Chubinsky A.N. Effect of Technical Aerosil on the Properties of Adhesive Compositions. Lesnoy Zhurnal [Russian Forestry Journal], 2021, no. 3, pp. 133–144. DOI: 10.37482/0536-1036-2021-3-133-144