Secagem da madeira de Eucalyptus grandis utilizando diferentes processos e impregnação de nanopartículas de prata

Abstract

Today there is an exponential growth in the use of Eucalyptus wood in the timber industries, mainly in products with higher added value, such as furniture and floors. In view of its importance in the forestry industry and in the commercialization of wood, there is a clear need for the implementation of technologies that provide better quality wood and improved drying processes. Therefore, the aim of this study is to evaluate the drying of Eucalyptus grandis's wood using different silver nanoparticle impregnation processes. For this purpose, logs of this species were used, obtained from Diagnosis and Agricultural's Department Research - RS. After unfolding and impregnating the silver nanoparticles in concentrations of 40 and 100 ppm in laboratory autoclave, the boards in the dimensions of 2.5 x 10 x 31 cm, respectively, thickness, width and length were submitted to drying in an air-conditioned chamber, with an average temperature of 20 ° C and a relative humidity of 65% and a laboratory oven with forced circulation with a constant temperature of 60 ° C, for subsequent tests of: moisture content, drying rate, defects, dynamic flexion, flexion static, biodeterioration and wettability. The results showed that there was a greater loss of humidity in those parts with 40 ppm impregnation with drying in an oven and an air-conditioned chamber, as well as a higher drying rate in an oven. In addition, there was a higher incidence of defects in those wood impregnated with 100 ppm and kiln dried, and those with 40 ppm impregnation and dried in the same method showed lower values than the control. The specific mass obtained mean values similar to those referenced in literature for the species worked. In addition, the dynamic flexion test identified greater resistance to impact in wood impregnated with 100 ppm and kiln dried, while the static flexion test showed better results for those parts impregnated with 40 and 100 ppm and chamber dried. Lastly, the biodeterioration tests didn't show significant results, however, those parts with 100 ppm impregnation had less loss of mass. In addition, the wettability test indicated that the boards with 100 and 40 ppm impregnation showed greater hydrophobic potential. From the results of this present study, it was possible to conclude that the impregnation of silver nanoparticles brings resistance and hygroscopic benefits to Eucalyptus grandis's woods.