Surface engineering of wood substrates to impart barrier properties: a photochemical approach

In this study, sugar maple and white pine, two species of wood commonly used in indoor and outdoor applications, were treated by photo-initiated chemical vapor deposition to impart barrier properties. After treatment, wood wettability decreased significantly, as evidenced by water contact angle measurements (from 50° to 113° for sugar maple and 87° to 172° for white pine). Further, beyond being able to repel water, the coating shows the ability to breathe, evidenced by standardized vapor sorption tests. However, accelerated weathering via ASTM G155 testing determined that the treatment could not protect the wood from photo-degradation, or retain its properties post-weathering. This treatment could therefore be best suited for wood pre-treatment in combination with other coatings

The Future of Quality Control for Wood & Wood Products

Abstract The moisture sorption profiles of Scots pine (Pinus sylvestris) early and late woods were studied using a Dynamic Vapour Sorption apparatus and analysed using the Parallel Exponential Kinetics model. The samples were chosen to give insight to the effects that photodegradation and weathering have on the moisture behaviour of surface layers of timber. Samples were subjected to indoor and outdoor exposure regimes. Significant differences were found between the sorption isotherms of exposed and unexposed wood, as well as with the sorption kinetics profiles. The isotherm differences are reported here. The reasons for these differences are discussed