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Juvenile and Mature Pinewoods Treated by in situ Polymerization with Poly(vinyl acetate)
Andrey Acosta,Ezequiel GALLIO,Paula Zanatta,Henrique Schulz,Rafael de Avila Delucis,Darci Gatto 한국섬유공학회 2021 Fibers and polymers Vol.22 No.3
This study aims to produce and characterize wood-based composites (WPC) by in situ polymerization withpoly(vinyl acetate) into juvenile and mature woods from a pine specie. Vacuum-pressure method was used to impregnate thewood with a vinyl acetate monomer and benzoyl peroxide (1.5 wt%) was used as initiator. The studied WPC werecharacterized for treatment parameters (weight percentage gain and specific gravity), as well as chemical (by infraredspectroscopy), thermal (by thermogravimetric analysis) and mechanical (by flexure and hardness tests) features. The in situpolymerization yielded improved mechanical properties and increased thermal stabilities, which were attributed to theimpregnated poly(vinyl acetate) (especially on the wood surface) as suggested by treatment parameters and infrared spectra. The presented wood treatment may be a key strategy to improve pinewood properties, especially from juvenile wood, whichmay overcome the properties of the pristine mature wood.
( Henrique Römer Schulz ),( Andrey Pereira Acosta ),( Kelvin Techera Barbosa ),( Mario Antonio Pinto Da Silva Junior ),( Ezequiel Gallio ),( Rafael De Ávila Delucis ),( Darci Alberto Gatto ) 한국목재공학회 2021 목재공학 Vol.49 No.3
This article aimed at thermally treating and charactering the Eucalyptus grandis wood under three different temperatures. For this, pristine eucalypt samples were treated by heating in a laboratory oven at 160 °C, 200 °C and 240 °C, always for 2 h. Treatment parameters (based on weight percentage loss and specific gravity), as well as mechanical (by hardness tests), chemical (by infrared spectroscopy), thermal (by thermogravimetry), and colorimetric (by CIELab method) features were evaluated. Compared to the pristine ones, the treated woods have there was a drop in apparent density at 12 % and consecutively greater thermal stability which is probably related to a previous partial degradation of some major amorphous components (namely cellulose, hemicellulose and lignin), as suggested by the treatment parameters and infrared spectra. Besides of that, the higher the temperature treatment, the higher the loss in surface hardness and the higher the colour darkening.