Box-Behnken design for process parameters optimalization of bamboo-based composite panel manufacturing

High performance bamboo-based composite panel taking bamboo mats, bamboo curtains and poplar veneers are used as raw material, is manufactured from the each layers slab was crisscrossed, impregnated with phenolic resin, compressed and cured. The product was optimized by Box-Behnken model design and data analysis. The results show that the best parameter conditions were hot pressing temperature of 140°C, hot pressing time of 94, and hot pressing pressure of 2.5 MPa. The model was validated according to the optimal process parameters and the static bending strength (MOR), elastic modulus (MOE), thickness expansion rate of water absorbing, adhesive strength and density are 98.95 MPa, 8.81 GPa, 4.7%, 1.25 MPa, 0.89, respectively. The actual value is close to the predicted value, confirming that the obtained model can accurately predict the MOR of the product using the three factors of hot pressing as variables under different conditions.

Effects of hot pressing parameters on the properties of hardboards produced from mixed hardwood tree species

In this work, wet-process fibreboards (hardboards) were produced in the laboratory using industrial wood fibres of the species European beech (Fagus sylvatica L.) and Turkey oak (Quercus cerris L.) at the total volume of 40%, and white poplar (Populus alba L.) at 60% volume. The effects of hot pressing pressure (varied from 3.3 MPa to 5.3 MPa) and pressing time (from 255 s to 355 s) on the physical and mechanical properties of hardboards were investigated and optimal values of the parameters for fulfilling the European standard requirements were determined. It was concluded that hardboards with acceptable physical and mechanical properties may be produced from 60% poplar wood waste and residues, combined with 40% hardwood raw materials (beech and oak) by regulating the hot pressing regime only, i.e. pressure and pressing time. The following minimum parameters for producing hardboards from mixed hardwood tree species were determined: a pressure of 4.6 MPa and a pressing time of 280 s.