Extra??o, reatividade e toxidez de extratos t?nicos da casca de Pinus oocarpa e Pinus caribaea var. bahamensis

• Ano de defesa: 2014
• Autor(a) principal: Vieira, Michel Cardoso
• Orientador(a): Lelis, Roberto Carlos Costa
• Banca de defesa: Abreu, Heber dos Santos, Nascimento, Alexandre Miguel do, Ferreira, ?rika da Silva, Vidaurre, Graziela Baptista
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal Rural do Rio de Janeiro
• Programa de Pós-Graduação: Programa de P?s-Gradua??o em Ci?ncias Ambientais e Florestais
• Departamento: Instituto de Florestas
• País: Brasil
• Palavras-chave em Português: cascas; adesivos; tanino
• Palavras-chave em Inglês: barks; adhesives; tannin
• Área do conhecimento CNPq: Recursos Florestais e Engenharia Florestal
• Link de acesso: https://tede.ufrrj.br/jspui/handle/jspui/3116

The aim of this work was the characterization of barks from Pinus oocarpa and Pinus caribaea var. bahamensis aiming its use in technological processes. The following properties were evaluated: The chemical properties of tannic extracts of barks from pinus and the potencial use of tannic extracts as adhesive, the reactivity of barks from Pinus oocarpa to formaldehyde, the effects of substances extracted from barks of Pinus oocarpa and Pinus caribaea var. bahamensis over life history of cladocerans Moina macrocopa and the properties of urea-formaldehyde (UF) and phenol-formaldehyde (PF) and its modifications with tannin from Pinus oocarpa and Pinus caribaea var. bahamensis. Results showed that quantification of total phenols from bark from pinus should not employ solvents with lesser polarity, due to the difficulty in solubilization of the species. For both species tested, addition of sodium sulfite increased tannin yield, being the treatment with addition of 5% sodium sulfite the most indicated for both species. Barks from both species showed potential to be employed as raw material to tannin obtainment, as the extractives showed satisfactory properties for gluing process, with exception of the tannic extracts of the bark from Pinus oocarpa, obtained in extraction with 10% sodium sulfite. The increase in the reaction time of the barks with formaldehyde resulted in an increase in solubilization of the components of the bark, occasioning higher extractive contents and a diminish in values of polyphenol content, for the barks before and after extraction. As for tannin content, there was a reduction after an increase in the reaction time, opposed to the non-tannins percentage, where the greater time of reaction with the formaldehyde solution favored solubilization of greater amounts. The 100% solution for both species was harmful for the cladocerans Moina Macrocarpa, resulting in death of the specimens. Lixiviated substancies from bark and sodium sulfite, due to the fact that it is a toxic product, may be the cause the cladocerans did not survive this concentration. As for other treatments, it was possible to observe that the solution did not alter the history of life aspects of the specie Moina Macrocopa. Addition of the tannic extract from Pinus oocarpa and Pinus caribaea bahamensis to urea-formaldehyde resin (UF) contributed for the redution in values of viscosity. As such, substitution of the synthetic adhesive by tannins from the bark is possible until 30%. The addition of the tannic extract of the bark from Pinus oocarpa and Pinus caribaea bahamensis to Phenol-formaldehyde (PF) contributed to an increase in values of viscosity. The replacement of synthetic adhesive by tannins from the bark of the two species is possible only up to 20%.The chemical characterization through infrared spectroscopy showed that adding tannin from both species to urea-formaldehyde resin made possible the visualization of aromatic bands in spectra, highlighting that a reaction between adhesive and tannin occurred.