| dc.description.abstract | Surface properties of wood such as surface roughness, wettability and surface
free energy (SFE) are important properties influencing further manufacturing
process such as finishing or adhesive strength characteristics. The aim of this
research was to determine surface properties such as surface roughness, SFE, and
wettability of ten tropical woods and its effect to their bonding quality of paints.
The woods tested in this study were fast-growing teak Biotrop variation, afrika,
sungkai, mindi, merbau, durian, lamtoro, pulai, acacia and kempas. Wood surfaces
were divided into unsanded and sanded using abrasive paper of 120 grits. SFE
values were calculated based on the Rabel method. Wettability were measured by
based on the contact angle between liquid paint and wood surface using sessile drop
method and (S/G) model was used to evaluate the wettability of the surface coatings
on the wood. Bonding quality of paints were measured using cross-cut test based
on the ASTM 3359-02 standard. The results indicated that sanding decrease the
surface roughness presented by Ra (arithmetical mean roughness), wettability and
SFE of wood but produce higher equilibrium contact angle. Higher K-Value
indicates higher wettability and bonding quality of paints. Afrika had greater
wettability of acrylic and alkyd paints than the other wood species. Cross-cut tests
showed that bonding quality of paints on ten wood species tend to decreased as the
surface became smoother. The oil-based alkyd paint was more wettable and
generates better bonding quality compared to the water-based acrylic paint. | en |
