3.4. TMA analysisThe classical mechanics relation between force and deflection allowed the calculation of the Young's modulus E (MOE) for each casetested [19,20].The MOE values obtained by TMA are shown in Fig. 4.The result indicates that the maximum MOE value of the TFF adhesive(1095 MPa) is higher than that of the TFG adhesive (1026 MPa). Formaldehyde added to a tannin-furfuryl alcohol system yields a higherMOE value than that of gloyxal in tannin-furfuryl alcohol. However, theaddition of 12% EPR in the TFG adhesive (TFG+12%EPR) presents anoticeable increase in MOE (1231 MPa) and achieved the maximumstrength of the joints bonded with the cross-linked TFG adhesive. And italso starts to increase at a lower temperature, which means the energyof activation of hardening of the TFG+12%EPR is apparently lowerthan TFF and TFG, this is confirmed by the thermomechanical analysistrace report previously [21]. Moreover, the MOE value of theTFG+12%EPR adhesive was highe