Water resistance improvement by polyethyleneimine of tannin-furfuryl alcohol adhesives

ABSTRACT

In this research furfuryl alcohol (FA) and polyethyleneimine (PEI) in different ratio were added to a tannin based adhesive in order to improve its moisture resistance. In order to characterize the functional groups involved, Fourier-transform infrared spectroscopy (FTIR) was used. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) were used to study the thermal behaviour of the formulations. FTIR spectroscopy indicated the reaction of quebracho tannin with FA and PEI. The results of the TGA showed that the added FA and PEI increased the resistance to thermal degradation. DSC analysis showed that the added FA and PEI reduced the heat absorption peak. According to the tensile shear strength of the formulations, the adhesive formulation T₁ F_0.75 P₂₀ (mixing proportion: Tannin 1, FA 0.75, PEI 20%) was able to satisfy the standards requirements (BS 1204-2) as a moisture resistant adhesive. Furthermore, this formulation presented the best tensile shear tests results and the least number of delaminated samples.

KEYWORDS:

• Water resistance
• Thermal analysis
• Infrared spectroscopy
• Tannin

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Antonio Pizzi http://orcid.org/0000-0002-9749-7185

Additional information

Funding

This work was supported by the Vice Chancellor for Research, Faculty of Natural resources, University of Tehran, I. R. Iran [grant number 30541/06/10].