Improvement in mechanical, physical and biological properties of eucalyptus and pine woods by raw pine resin in situ polymerization

Abstract

A raw pine resin, which is a cheap, renewable and easily obtainable forest resource, was used to impregnate two different fast-growing solid woods (Eucalyptus grandis Hill Maiden and Pinus elliottii Engelm) and in situ polymerized to improve their hygroscopic, chemical, morphological, mechanical, and thermogravimetric properties. Biodegradation resistance against subterranean termites and white-rot fungus was also addressed. The treatment yielded changes in colorimetric properties, dimensional stability and surface hydrophobicity. Compared to its respective untreated wood, the treated pine one presented increases within 40-50 % in ASE, whereas the treated eucalyptus wood showed negative values around -15 % in this same comparison. Increases in MOE (70 %) and MOR (50 %) were obtained for the pine wood, whereas the same properties were unaffected for the eucalyptus wood. Thermal and biological properties of both woods were also positively affected. These results were associated with the solidified raw pine resin inside the wood structure, which was confirmed by infrared spectroscopy and SEM images, especially for the pine due to its large and long tracheids, as well as its lignin content and overall composition.

Anaerobic Co-Digestion of Human Feces with Rice Straw for Biogas Production: A Case Study in Sunyani

“…Because of this, microorganisms have difficulty degrading these rice straws compared to the degradation of human fecal matter. Biochemical degradation of lignin explains the general limitation role of bacteria in the degradation of lignin macromolecules since bacteria are only responsible for the decomposition of side chains and monomers [32]. Likewise, the results presented by [18,33] both worked on lignin degradation and shown that bacteria can detach the aliphatic side chains from the molecule but that the phenol-ether bonds remained non-localized by the bacteria.…”

Wood Flour Modified by Poly(furfuryl alcohol) as a Filler in Rigid Polyurethane Foams: Effect on Water Uptake

“…This forest-based resource was oven dried at 50 • C until reaching a constant weight, milled using a Wiley mill, and then sieved using a 100-mesh screen. The resulting wood flour was characterized via wet-chemical analysis to obtain ethanol-toluene extractives [23], acid-insoluble lignin [24], ashes [25], and holocellulose (remaining mass percentage) contents.…”

Hidrofobização e odorização de madeira para uso na construção civil por imersão em nanoemulsões de óleo essencial de melaleuca e copaíba

“…Nesse sentido, o desenvolvimento de novos tipos de tratamentos alternativos aos mais tradicionais, têm sido investigados, com o intuito de proporcionar variações positivas nas propriedades da madeira, que vão desde o aumento da resistência biológica até o incremento da estabilidade dimensional. Entre os estudos, destaca-se a polimerização in situ com monômeros [11,12], termorretificação [13,14] e impregnação com produtos naturais [15,16]. Assim, a busca por novas soluções, como os tratamentos superficiais, faz-se necessário para garantir a melhoria das propriedades deste tipo de madeira, com intuito de inibir a ação de agentes externos de degradação, a fim de proporcionar um desempenho e durabilidade satisfatórios.…”