Envelhecimento artificial acelerado por radiação ultravioleta de madeiras de Eucalyptus benthamii e pinus caribaea var. hondurensis

Abstract

The main objective of this research was to study the photo degradation process of superficial color of two wood species, Pinus caribaea var. hondurensis and Eucalyptus benthamii, over ultraviolet irradiation exposure time in a photochemical reactor. Pinus caribaea var. hondurensis samples were evaluated in the radial plane, while Eucalyptus benthamii samples were in tangential plane. The colorimetric parameters measures under the CIELAB 1976 system (L*, a*, b*, C, e h*) were obtained using a Spectophotometer, in the following time intervals: 0, 42, 84, 126 and 168 hours. Both species presented darkening over time, especially in the first hours of exposure. The E. benthamii wood had more changes in its color parameters (ΔE=19.72) than P. caribaea var. hondurensis wood (ΔE=17.82) after 168 hours.