STUDY OF THE INFLUENCE OF COMPOUNDS OF THE ANO3 and ANO3 nH2O TYPES ON RHEOKINETIC AND COLLOID-CHEMICAL PROPERTIES OF ALUMINOSILICATE ADHESIVES FOR WOOD

Abstract

In the technology of gluing solid wood, various adhesives are used, which, in addition to ensuring the strength of the gluing, must also be characterized by a number of rheological and colloidal-chemical properties, namely: have acceptable viscosity, low contact angles, have good spreading and enveloping ability, penetrate deep into the wood , providing reliable cohesive-adhesive contact and much more. Today, adhesives based on PVA dispersions and urea formaldehydes are used, the properties of which have been sufficiently studied and tested in practice. An alternative to organic-based adhesives is mineral adhesives, in particular aluminosilicate adhesives, which are non-flammable and have high mechanical strength.
 Object of research: rheokinetic patterns and processes of formation of colloidal-chemical structures of aluminosilicate adhesives modified with compounds of the ANO3 and ANO3×nH2O type.
 Investigated problem: Considering that aluminosilicate adhesives are multiphase reactive suspensions, the viscosity of which changes over time and affects their viability, the issue of viscosity stabilization due to the introduction of electrolyte salts into their composition is relevant, and will also contribute to improving the wettability and spreading of the adhesive during applying them to substrates and gluing samples from various types of wood.
 Main scientific results: The effect of the concentrations of compounds of the ANO3 and ANO3×nH2O type on the rheokinetic and chemical-colloidal properties of the aluminosilicate adhesive has been established, which will make it possible to use aluminosilicate adhesives in practice for gluing wood of various species, as well as to work out possible technological methods of their application, taking into account the obtained data on the viscosity, wetting and spreadability of the modified adhesive on the surface of the wood substrate.
 Area of practical use of the research results: woodworking enterprises for the production of glued solid wood products.
 Innovative technological product: aluminosilicate adhesives modified with ANO3 and ANO3×nH2O nitrate additives for gluing wood of various species.
 Scope of application of an innovative technological product: the application of these approaches will make it possible to obtain glued materials from wood from different species with improved technological and physical and mechanical properties of the glue seam and, accordingly, to increase the quality and reliability of products.

Influence of Nitrate Species A(NO₃)₂ on Physico-Mechanical Properties of the Aluminosilicate Adhesives for Wooden Structure

“…When modifying the aluminosilicate adhesive Ca(NO3)2 in an amount of 0.5 and 1.5% (Fig. 2, b), on the 7th day of curing, a decrease in strength values by 1.2 and 1.3 times was noted compared to the control adhesive (C=0%) [1]). At a concentration of calcium nitrate in an amount of 1%, an increase in strength by a factor of 1.21 is noted, and the maximum peak on the fracture curve is observed on the fracture curve, which is described by a curved quadratic function of the form: The same trend is also observed after 28 days of curing, when the strength values at a calcium nitrate concentration of 0.5 and 1.5% decrease by 2.73 and 1.93 times compared to the control value, and at a calcium nitrate concentration of 1%, its increase is 1.06 times compared to with a control adhesive and on the fracture curve, there is a maximum peak on the fracture curve, which is described by a curved quadratic function of the form: (8) When modifying the aluminosilicate adhesive with a mixture of nitrates 95%Ca(NO3)2+5%NH4NO3 in an amount from 0.5 to 1.5% (Fig.…”

“…It was noted that on the 7th day of curing (Fig. 1, a), an increase in the concentration of Mg(NO3)2 from 0.5 to 1.5% contributes to a decrease in strength, respectively, by 1.02, 2.18 and 1.85 times compared with the strength without additional (control) aluminosilicate adhesive (C=0%) [1]. On the 28th day after curing, an increase in shear strength along the fibers by 1.23 times was noted compared with the control adhesive at a Mg(NO3)2 content of 1%, in the case of other concentrations, a decrease in strength by 1.28 and 1.01 times was noted compared to the control adhesive.…”

“…When modifying the aluminosilicate adhesive Mg(NO3)2 in an amount of 0.5 and 1.5% (Fig. 2, a), on the 7th day of curing, a decrease in strength values by 1.66 and 1.3 times was noted compared to the control adhesive (C=0%) [1]. At a concentration of magnesium nitrate in an amount of 1%, an increase in strength by a factor of 1.22 is noted, and the maximum peak on the fracture curve is observed on the fracture curve, which is described by a convex quadratic function of the form:…”

“…This study is a continuation of a series of works devoted to the study of the effect of modifiers of aluminosilicate adhesives for gluing wood. The works [1][2][3] present data on the effect of monovalent metal nitrates on rheokinetic and colloid-chemical, strength and deformation properties. In this paper, the main focus will be on the effect of divalent metal nitrates on the physical and mechanical properties of aluminosilicate adhesives for wood bonding.…”

Influence of Nitrate Species ANO₃ and ANO₃·nH₂O on Physico-Mechanical Properties of the Aluminosilicate Adhesives for Wood and Wooden Structures

“…This study is a continuation of a series of works devoted to the study of the effect of monovalent metal and non-metal nitrates as modifiers of aluminosilicate adhesives for gluing wood and structures based on them. The work [1] provides data on the effect of the above compounds on rheokinetic and colloidal-chemical properties. In this work, the main emphasis will be on the effect of nitrate compounds on the physical and mechanical properties of aluminosilicate adhesives for gluing wood and wooden structures.…”