Modulus of elasticity (MOE) of the tannins formulations were
studied using thermal mechanical analyzer with TA controller
(Mettler TMA 40). About 5 g of a 30% (w/w) of lyophilized tannins
solution, 5% of powdered paraformaldehyde on a dry and solid tannins
matter content basis were added and mixed together. 30mg
of the mixture was coated in one side of two small wood chips
(5mm×20 mm), which were tested by three points bending TMA
mode. The test condition: heating rate of 10 ◦C/min from 25 to
250 ◦C.