Original scientific paper

Effect of thermal post-treatment on some surface-related properties of oriented strandboards

Cláudio Henrique Soares Del Menezzi ; Department of Forest Engineering, Faculty of Technology, University of Brasília, Brasília, Brazil
Raquel Bahia Ribeiro ; Department of Forest Engineering, Faculty of Technology, University of Brasília, Brasília, Brazil
Gerson Henrique Sternadt ; Forest Products Laboratory, Brazilian Forest Service, Brasília, Brazil
Divino Eterno Teixeira ; Forest Products Laboratory, Brazilian Forest Service, Brasília, Brazil
Esmeralda Yoshico Arakaki Okino ; Forest Products Laboratory, Brazilian Forest Service, Brasília, Brazil

Abstract

A very promising method for improving the dimensional stability of oriented strandboard (OSB) has been studied in Brazil since 2001. According to this method, the OSB is thermally treated under mild conditions using a hot-press, where it is reheated without high level of compression stress. The properties of the treated OSB panels are different from and enhanced compared to those untreated ones. It means that the treated OSB can be used in more severe uses, like concrete formwork. This paper aims to evaluate the effect of the proposed thermal treatment on nail-holding capability and on surface hardness of OSB. Samples from 42 commercials OSB were thermally
treated according to two levels of temperature (190°C and 220°C) and three heating times (12, 16 and 20 min) using a single opening hot-press. For comparison, control panels were kept untreated. The following surface-related properties were evaluated: Janka hardness, nail-holding capability in a plane normal to the surface, in the edge of the panel, water absorption and thickness swelling (TS) of edge sealed samples, and four surface roughness parameters. According to the Dunnett test, there were significant differences between treated and untreated panels for nail-holding, dimensional stability and surface roughness. The factorial ANOVA identified that the temperature was the main factor governing these properties while the duration of the treatment had lesser effect. It was concluded that the proposed thermal treatment improved significantly dimensional stability and did not affect adversely the nail-holding capability and surface roughness of the treated OSB.

Keywords

oriented strandboard; surface properties; thermal treatment

Hrčak ID:

25405

URI

https://hrcak.srce.hr/25405

Publication date:

18.7.2008.

Article data in other languages: croatian

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