CARACTERIZAÇÃO TECNOLÓGICA DA MADEIRA DE Trattinnickia burserifolia Mart. SUBMETIDA AO TRATAMENTO DE ACETILAÇÃO

O tratamento de acetilação é um processo químico de modificação da madeira que visa melhorar algumas das suas propriedades, agregando maior valor ao produto final. Deste modo, objetivou-se avaliar as propriedades físicas, mecânicas e biológicas da madeira acetilada de Trattinnickia burserifolia Mart. (amescla). Os tratamentos de acetilação efetuaram-se por imersão em anidrido acético durante dois períodos de tempo – 3 e 6 horas – com temperatura constante de 80ºC. O tempo de tratamento de acetilação influenciou significativamente no ganho de massa da madeira, sendo verificados os maiores valores para o tratamento de 6 horas. Por outro lado, a massa específica não foi influenciada significativamente pelo tempo de tratamento. Na absorção em água e retratibilidade volumétrica, após o tempo de 2 horas, 24 horas e saturação total, o tratamento de 6 horas foi o mais eficaz. Na propriedade mecânica de dureza Rockwell, evidenciou-se que a madeira tratada apresentou maiores valores de resistência mecânica. A acetilação da madeira de amescla proporcionou aumento da resistência biológica ao ataque de cupins xilófagos.Palavras-chave: modificação química; qualidade da madeira; madeira tropical. TECHNOLOGICAL CHARACTERIZATION OF AMESCLA WOOD SUBMITTED TO ACETYLATION TREATMENT ABSTRACT: The acetylation treatment is a chemical process of wood modification that aims to improve some of its properties, adding more value for the final product. In this way, this study aimed to evaluate the physical, mechanical and biological properties of the amescla wood. The acetylation treatment was performed by immersion in acetic anhydride over two time periods – 3 and 6 hours – with a constant temperature of 80°C. The time period of acetylation influenced significantly in the WPG (weight percentual gain) of the wood, and the highest values were noticed for the 6 hours treatment. On the other hand, the density was not significantly influenced by the treatment time. In water absorption and volumetric swelling after 2 hours, 24 hours and full saturation, the 6 hours treatment was most effective. The mechanical property of Rockwell hardness demonstrated that the treated wood had higher mechanical strength values. The acetylation of amescla wood has provided increased biological resistance to xylophagous termites.Keywords: chemical modification; wood quality; tropical wood.

[1]  T. Koddenberg.  Handbook of Wood Chemistry and Wood Composites , 2016 .

[2]  R. Rowell.  Dimensional stability and fungal durability of acetylated wood , 2016 .

[3]  S. Cragg,et al.  Resistance of modified wood to marine borers , 2015 .

[4]  G. Olatunji,et al.  Acetylation of Wood Flour from Four Wood Species Grown in Nigeria Using Vinegar and Acetic Anhydride , 2013 .

[5]  N. Özmen,et al.  A NEW APPROACH FOR ACETYLATION OF WOOD: VINYL ACETATE , 2012 .

[6]  A. Papadopoulos,et al.  The effect of acetylation on the Janka hardness of pine wood , 2011, European Journal of Wood and Wood Products.

[7]  P. Larsson-Brelid,et al.  Biological degradation of acetylated wood after 18 years in ground contact and 10 years in marine water , 2010 .

[8]  B. Mohebby,et al.  Microbial attack of acetylated wood in field soil trials , 2010 .

[9]  A. Papadopoulos.  Chemical modification of solid wood and wood raw material for composites produciton with linear chain carboxylic acid anhydrides: A brief review , 2009, BioResources.

[10]  R. Rowell,et al.  Understanding decay resistance, dimensional stability and strength changes in heat-treated and acetylated wood , 2009 .

[11]  G. Alfredsen,et al.  Durability of Modified Wood - Laboratory vs Field Performance , 2009 .

[12]  Antonios N. Papadopoulos,et al.  The biological effectiveness of wood modified with linear chain carboxylic acid anhydrides against the subterranean termites Reticulitermes flavipes , 2008, Holz als Roh- und Werkstoff.

[13]  Roger M. Rowell,et al.  Effect of Humidity on Vibrational Properties of Chemically Modified Wood , 2007 .

[14]  Benedito Rocha Vital,et al.  Propriedades de chapas tipo OSB, fabricadas com partículas acetiladas de madeiras de Eucalyptus grandis, Eucalyptus urophylla, Eucalyptus cloeziana e Pinus elliottii , 2006 .

[15]  C. Hill,et al.  Wood Modification: Chemical, Thermal and Other Processes , 2006 .

[16]  J. Gril,et al.  Swelling of acetylated wood I. Swelling in organic liquids , 2005, Journal of Wood Science.

[17]  Jianzhang Li,et al.  Chemical modification of wood by anhydrides without solvents or catalysts , 2000, Journal of Wood Science.

[18]  P. Gatenholm,et al.  Effect of acetylation on the material properties of glucuronoxylan from aspen wood , 2003 .

[19]  E. Beckers,et al.  Mechanical properties of acetylated solid wood treated on pilot plant scale , 2003 .

[20]  P. Aggarwal,et al.  Moisture adsorption behaviour of esterified rubber wood (Hevea brasiliensis) , 2001, Holz als Roh- und Werkstoff.

[21]  Y. Imamura,et al.  Resistance of Acetylated Wood to Attack by Subterranean Termites , 1986 .