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 T 1 F 0.75 P 20 (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.

Tannin as a renewable raw material for adhesive applications: a review

“…203 Investigation by Shirmohammadli and colleagues reported that the moisture resistance of tannin adhesives can be improved by incorporating PEI and furfuryl alcohol. 205 Condensation reactions between amine groups in PEI and hydroxyl groups of furfuryl alcohol were evident from the FT-IR analysis. The thermal stability of the adhesives increased on addition of PEI and furfuryl alcohol.…”

Characterization of Fast Pyrolysis Bio-Oil from Hardwood and Softwood Lignin

“…The mode and the conditions of pyrolysis can affect the relative proportions of the gas, liquid, and solid products. The cellulose, hemicellulose, and lignin are the three main components of biomass, and all these three main components of biomass are determined as the elements of hydrogen, carbon, and oxygen [22] and high energy content can be relieved by pyrolysis process [23,24]. Lignin occurs throughout the plant cell-wall, and in comparison to cellulose and hemicellulose, carries the highest specific energy content [25] and is a by-product of the bleaching process of wood pulp.…”