ВЛИЯНИЕ ФАКТОРОВ ПРОЦЕССА ПРОИЗВОДСТВА НА ПОКАЗАТЕЛИ ФАНЕРЫ НА МОДИФИЦИРОВАННОМ ФЕНОЛОФОРМАЛЬДЕГИДНОМ СВЯЗУЮЩЕМ

Abstract

To reduce production costs, FSF plywood is produced by pressing at a reduced temperature. However, at the same time, the resite stage is not provided for the phenol-formaldehyde binder, which results in a decrease in the physical and mechanical properties of plywood. In the world and Russian practice of scientific work, this problem is solved in various ways: by modifying the binder at the stage of its synthesis, by preliminary surface treatment of veneer, by modifying phenol-formaldehyde binder at the stage of synthesis or “on site”. To develop a rational combination of the values of the production process factors, which makes it possible to form a more durable structure of plywood during low-temperature pressing, a modification of the binder with the addition of dimethylglyoxime was used. An experiment was carried out on the B-plan of the 2nd order. The following varied: proportion of dimethylglyoxime addition (from 0.5 to 1.5% of the binder mass), pressing temperature (from 110 to 130 ºС), pressing time (from 4 to 5 min). Regression models have been developed for the ultimate strength of plywood when chipping along the adhesive layer, ultimate strength in static bending, and thickness swelling of plywood after 24 hours in water. It was found that with an increase in the proportion of dimethylglyoxime additive to 1.5%, the shear strength of plywood increases by 25%, the static bending strength by 30%, and thickness swelling by 10%. This allows us to conclude about the deepening of the process of structure formation of FSF plywood when pressed on a modified binder. Recommendations for the rational combination of the values of the factors of the production process of FSF plywood have been developed