Protective behaviour monitoring on wood photo-degradation by spectroscopic techniques coupled with chemometrics

This paper reports the investigation on the effect of protective materials on poplar (Populus sp.) wood modifications as consequence of artificial photo-degradation in controlled environment. The novelty of this work is to try to understand what happens to wood surface under the protective layer. Shellac, beeswax and Linfoil® were tested to compare traditional and novel products generally used for wood. The samples, uncovered and covered by these protective layers, were artificially aged. Colour and chemical modifications due to ageing were investigated at different time intervals by reflectance spectrophotometry, Fourier transform infrared spectroscopy and hyperspectral imaging. The obtained data were elaborated by statistical and chemometric tools in order to verify their significance and to assess the relationship between groups of measurements. The results highlighted that shellac, beeswax and Linfoil® materials have a very low protective effect on wood photo-degradation for long times of exposure, by little reducing the changes of wood components.