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Submitted in partial fulfillment of the requirements for the degree of Master of Technology: Chemistry, Durban Institute of Technology, Durban, 2003. / Boron, in spite of its exceptional properties as a timber preservative, is not widely used for this purpose. The three key agents that contribute to the destruction of timber are insects, fungi and ultraviolet radiation. Boron is a good fungicide and insecticide and the acrylic/styrene polymer blend resists ultraviolet attack. Treating timber with boron compounds is very easy and, in most instances, does not require sophisticated equipment. The movement of boron into timber is diffusion driven and requires moisture of between 30-50% in the timber. Unfortunately, this superb mobility of boron results in one major disadvantage, namely, the leaching of boron when moisture enters timber. Various methods have been used to impede the movement of boron out of timber (wax coating, paints, varnishes and water-based polymer coatings. None of them have been completely successful. For instance, varnishes, used to prevent boron from leaching out of timber are unsuitable because they also prevent moisture leaving the timber. This results in blistering of the coatings used to contain the boron. In this project, an all-in-one system was developed by systematically varying the nature of the boron compound and the polymer. The successful formulation, which contained disodium octaborate tetrahydrate, as the source of boron and a styrene acrylic polymer blend, has been found to: Allow the uninhibited diffusion of boron into timber. Form a clear continuous polymer film on curing on the surface of the timber. o Display good resistance to ultraviolet attack on the polymer and the timber substrate The product developed has been formulated with the following concentrations: 60 grams per litre of boric acid equivalent 150 grams per litre of boric acid equivalent 200 grams per litre of boric acid equivalent The efficiency of the acrylic/styrene polymer barrier was shown by performing qualitative tests for the presence of boron on the surface of the timber treated with the all-in-one formulation. Furthermore, leaching tests were performed by submerging the treated timber in water and thereafter, analyzing the water for leached boron at regular intervals. The results of these tests showed that the new formulation (60 gIL, 150 gIL and 200 gIL) is suitable for treatment of timber that is destined for above - ground applications. The preservative containing a concentration equivalent to 60 gIL of boric acid was sufficient for remedial treatment. The preservative containing an equivalent of 150 gIL and 200 g/L of boric acid was ideal for treating freshly felled timber. The patent application for this preservative has been accepted. / M

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Orientador: Elias Taylor Durgante Severo / Coorientador: Fred Willians Calonego / Banca: Ademilson Coneglian / Banca: Cláudio Angeli Sansíglo / Resumo: A preservação química de madeira para uso rural é feita, na grande maioria dos casos, utilizando-se a espécie Corymbia citriodora. Essa espécie tem sido a mais aceita no mercado embora sua tecnologia silvicultural e melhoramento genético tenha ficado aquém de outras espécies de Eucalyptus spp. Assim o objetivo deste trabalho foi avaliar o potencial de várias espécies de Eucalyptos spp. para substituir o Corymbia citriodora no tratamento preservativo industrial. Para isso foram empregados 3 tratamentos que variavam o tempo de pressão em autoclave, contendo cada um deles 9 espécies comerciais de Eucalyptus spp., com 5 repetições cada. As espécies selecionadas foram extraídas de um mesmo povoamento com 4 anos de idade, e mourões com classe de diâmetro de 10 a 16 cm. Foram utilizados os tratamentos embasaram-se no processo industrial de preservação com variação do tempo de pressão entre 30 minutos, 1 hora e 2 horas. Foram avaliados a massa específica a 0% de umidade, rachaduras e fendas das peças de madeiras e a penetração e a retenção do produto químico CCA-C nos mourões das diferentes espécies. O maior índice de rachaduras de topo do mourão foi observado na espécie E. urophylla x E. grandis I-144 5,9 mm e o menor índice de rachadura de topo foi da espécie E. camaldulensis VM-58 1,2 mm, e o maior índice de abertura de fenda de topo de mourão observada foi para a espécie E. urophylla I-220 com 25,9 mm e o menor índice de abertura de fenda de topo foi da espécie E. urophylla x E. grandis VM19 com 9,3 mm. Conclui-se que é possível a substituição do C. citriodora por novas espécies para uso como mourão preservado quimicamente. Os resultados demonstraram a eficiência do tratamento preservativo nas diferentes espécies com valores de retenção que variaram entre 5,2 e 11,7 kg/m³, respectivamente para as espécies Eucalyptus urophylla x Eucalyptus grandis GG100 / Abstract: The preservation of wood chemistry for rural use is made, in most cases, utilizing the type Corymbia citriodora. This species has been widely accepted in the market though its silviculture and genetic improvement technology has lagged behind other species of Eucalyptus spp. The objective of this study is to evaluate the potential of Eucalytus spp. to replace the Corymbia citriodora in industrial preservative treatment. For that three treatments were applied time varying pressure in an autoclave, each containing nine commercial species of Eucalyptus sp., with 5 replications. The species used were extracted from the same stand 4 years of age and class diameter of 10 to 16 cm. The treatments used in the industrial process of conservation with time-varyng pressure from 30 minutes, 1 hour and 2 hours. We evaluated the density at 0% moisture, cracks and crevices of wood and the penetration and retention of the chemical CCA-C stakes in the different species. The highest top the gatepost end checks were observed in the species E. urophylla x E. grandis I-144 5,9 mm and the lowest was end checks top the species E. camaldulensis VM-58 1,2 mm, and the highest rate of crack opening top of gatepost was observed for the species E. urophylla x E. grandis I-220 with 25,9 mm and the lowest opening slot top was kind of E. urophylla x E. grandis VM-19 with 9,3 mm. It is concluded that it is possible to replace C. citriodora by new species for use as a gatepost chemically preserved. The results demonstrated the effectiveness of preservative treatment in different species with retention values ranging between 5,2 and 11,7 kg/m³, respectively for the species E. urophylla x E. grandis GG-100 half four with pressure and E. urophylla x E. grandis VM-19 with 2 hours of pressure, allowing a wide variation to differentiate and characterize the species studied / Mestre

Made available in DSpace on 2014-06-11T19:30:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-09-28Bitstream added on 2014-06-13T20:27:07Z : No. of bitstreams: 1 lima_fcc_me_botfca.pdf: 674462 bytes, checksum: c3701abef9b3816bc3df3115365aa2dd (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / A preservação química de madeira para uso rural é feita, na grande maioria dos casos, utilizando-se a espécie Corymbia citriodora. Essa espécie tem sido a mais aceita no mercado embora sua tecnologia silvicultural e melhoramento genético tenha ficado aquém de outras espécies de Eucalyptus spp. Assim o objetivo deste trabalho foi avaliar o potencial de várias espécies de Eucalyptos spp. para substituir o Corymbia citriodora no tratamento preservativo industrial. Para isso foram empregados 3 tratamentos que variavam o tempo de pressão em autoclave, contendo cada um deles 9 espécies comerciais de Eucalyptus spp., com 5 repetições cada. As espécies selecionadas foram extraídas de um mesmo povoamento com 4 anos de idade, e mourões com classe de diâmetro de 10 a 16 cm. Foram utilizados os tratamentos embasaram-se no processo industrial de preservação com variação do tempo de pressão entre 30 minutos, 1 hora e 2 horas. Foram avaliados a massa específica a 0% de umidade, rachaduras e fendas das peças de madeiras e a penetração e a retenção do produto químico CCA-C nos mourões das diferentes espécies. O maior índice de rachaduras de topo do mourão foi observado na espécie E. urophylla x E. grandis I-144 5,9 mm e o menor índice de rachadura de topo foi da espécie E. camaldulensis VM-58 1,2 mm, e o maior índice de abertura de fenda de topo de mourão observada foi para a espécie E. urophylla I-220 com 25,9 mm e o menor índice de abertura de fenda de topo foi da espécie E. urophylla x E. grandis VM19 com 9,3 mm. Conclui-se que é possível a substituição do C. citriodora por novas espécies para uso como mourão preservado quimicamente. Os resultados demonstraram a eficiência do tratamento preservativo nas diferentes espécies com valores de retenção que variaram entre 5,2 e 11,7 kg/m³, respectivamente para as espécies Eucalyptus urophylla x Eucalyptus grandis GG100 / The preservation of wood chemistry for rural use is made, in most cases, utilizing the type Corymbia citriodora. This species has been widely accepted in the market though its silviculture and genetic improvement technology has lagged behind other species of Eucalyptus spp. The objective of this study is to evaluate the potential of Eucalytus spp. to replace the Corymbia citriodora in industrial preservative treatment. For that three treatments were applied time varying pressure in an autoclave, each containing nine commercial species of Eucalyptus sp., with 5 replications. The species used were extracted from the same stand 4 years of age and class diameter of 10 to 16 cm. The treatments used in the industrial process of conservation with time-varyng pressure from 30 minutes, 1 hour and 2 hours. We evaluated the density at 0% moisture, cracks and crevices of wood and the penetration and retention of the chemical CCA-C stakes in the different species. The highest top the gatepost end checks were observed in the species E. urophylla x E. grandis I-144 5,9 mm and the lowest was end checks top the species E. camaldulensis VM-58 1,2 mm, and the highest rate of crack opening top of gatepost was observed for the species E. urophylla x E. grandis I-220 with 25,9 mm and the lowest opening slot top was kind of E. urophylla x E. grandis VM-19 with 9,3 mm. It is concluded that it is possible to replace C. citriodora by new species for use as a gatepost chemically preserved. The results demonstrated the effectiveness of preservative treatment in different species with retention values ranging between 5,2 and 11,7 kg/m³, respectively for the species E. urophylla x E. grandis GG-100 half four with pressure and E. urophylla x E. grandis VM-19 with 2 hours of pressure, allowing a wide variation to differentiate and characterize the species studied

In 1977, sixty-two white spruce pole sections were installed at the Western Forest Products Laboratory's Westham Island test field site. They had been commercially pressure-impregnated with ammoniacal copper arsenate (ACA) or pentachlorophenol (PCP). Twenty-four of the ACA-treated spruce poles were studied to determine the influence of preservative penetration, retention, and nitrogen level on decay resistance of spruce poles after seven years of field testing. Such information was considered of great value in establishing treated spruce as viable pole material in Canada. Studies using a 0.5% solution of chrome azurol S indicated that for the ACA-treated spruce poles after seven years in test, average preservative penetration of 1.14 in. (2.90 cm) was generally greater than that required by Canadian standards. However, analysis using energy-dispersive X-ray spectrometry showed that the mean retention of 0.50 lb./ft.³ (8.06 kg/m³) was less than the level of 0.6 lb./ft.³ (9.6 kg/m³) for ACA, required by the CSA standard. It was also found that copper was present in greater quantity than arsenic, in spite of their equal presence in the original ACA treating solution. In microbiological studies, a total of seventy-one fungal isolates belonging to seventeen genera and four taxa were identified to genus, with fifteen of these identified as to species. Unlike the untreated control poles, true wood-decaying Basidiomycetes were not found associated with the ACA-treated spruce poles. Analysis employing an Orion ammonia-specific electrode coupled to an Orion Microprocessor ionalyser 901 revealed that nitrogen content due to ACA treatment was significantly increased in the treated zone and also beyond the penetration limit of preservative. A linear relationship existed between nitrogen content and chemical retention in the first analytical zone. Variation in moisture content above the fiber saturation point produced marked changes in electrical resistance as detected by Shigometer measurements. The practical application of the Shigometer for detection of internal decay is limited by such inconsistencies. / Forestry, Faculty of / Graduate

This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.

Literature reports have indicated that application of sonic pressure waves enhances the rate of impregnation of preservatives in wood. However, these studies have been limited and inconclusive. The technique or process is not in commercial use. In this study a laboratory scale treating cylinder connected to a mechanical sonic wave generator was used to measure the rate of impregnation of water in ponderosa pine at pressures of 0.28, 0.55 and 0.69 MPa and Douglas-fir at pressures of 0.55 and 0.69 MPa at a frequency of 30 Hz. Results were compared with those obtained at the same conditions of static hydraulic pressure. Statistical analysis showed that sonic treatments were at least as effective as, but not consistently superior to, hydraulic pressure treatments in the case of ponderosa pine. Statistical analysis of the results from Douglas-fir treatment showed that sonic treatment was superior than hydraulic treatment. / Graduation date: 1995