Wood coatings protect the wooden substrate against external exposure factors as well as improve the aesthetic view of the object. Cured coating films need to be stretchable in order to follow substrate dilatations and shrinkage. To investigate the adaptation ability of coatings to dimensional changes of a substrate, we tested the tensile strength of free films of wood coatings. 10 different coatings and 8 different substrates for application of coating films were selected. Testing of the substrates for application and removal ability of free coating films resulted in selection of two suitable materials, teflon and polypropylene. We manually applied the coatings on 500 mm long teflon and polypropylene plates trough the applicator slot of 240 %m. The films were firstly removed from the plates and then they were cut into the samples. Afterwards their elasticity was evaluated. The measurements were performed with a device Zwick Roell Z005, with 10 samples per each coating. The films were stretched by different speed until the breaking point. We have concluded that the coatings for outdoor use are more elastic than the coatings for internal use, however they are softer. On the other hand, the coatings for indoor applications are less flexible and harder.
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