INFLUENCE OF THE TEMPERATURE OF PRESSING ON THE PROPERTIES OF PARTICLE BOARDS MADE WITH FURAN RESIN BINDERS

Abstract

Introduction. Physical and mechanical properties of carbamide-formaldehyde-based and phenolformaldehyde-based  boards do not meet requirements  of consumers of construction sector and furniture industry. Water resistance is the major problem of the boards. One possible way for improving the performance properties of the boards is to use alternative water-resistant adhesives (e.g. oligomers of furan series) as a binder. Thermodynamic and physical and chemical properties of monomer FA can implement it in production of wooden boards. The purpose of the research is to assess the influence of pressing temperature on physical and mechanical properties of particle boards made with the use of furfural-acetone monomer FA. Objectives: definition of the efficient temperature of hot pressing of wood particle boards on the base of furfural-acetone monomer FA. The technique of experimental studies. The samples of particle boards were manufactured and tested.  Pressing of boards was carried out at the temperatures 160 – 220°C. Special cut chips of deciduous and coniferous wood with a selection of fraction 10/2 and the adhesive composition on the base of furfural-acetone monomer FA in the mixture with 5% hardener – n-toluensulfonate were used. Production of boards was carried out in a laboratory hydraulic press under the following constant factors: thickness of the boards  – 16 mm; calculated density – 800 kg/m³; compression molding pressure  – 2 MPa; duration of holding pressure  – 8 min; binder consumption  – 12 % of weight of absolutely dry chip. Results. Strength characteristics of boards have a maximum value at the temperature of pressing 200°C. At the temperature above 200°C, there is a decrease in strength. After soaking the samples of the boards, their strength is reduced. Indicators of swelling and water absorption and mass loss during combustion are significantly reduced when the temperature of pressing boards grows. This phenomenon is explained by more complete curing of the binder. At the temperature above 200°C,  swelling does not exceed 8,5 %, loss of weight – not more than 17 %.  Conclusion. Production of wood boards on the base of furfural-acetone monomer FA at high temperatures of pressing allows toobtain a structural material with high strength and good water resistance that can be effectively used in construction and other areas of production with variable temperature and humidity conditions.