Study on gluing reaction between WPI adhesive and bamboo by means of DSC

Abstract

Purpose

The purpose of this paper is to study interactions between water‐based polymer isocyanate (WPI) adhesive and bamboo by means of differential scanning calorimetry (DSC).

Design/methodology/approach

The method of adapting new reference substance replacing aluminium was used due to the special characteristic of WPI adhesive when studying reactions between WPI adhesive and bamboo.

Findings

The methods of changing reference substance could counteract effect of water in the sample on DSC measurement. The results of DSC analysis showed that hardener of WPI adhesive can react with water and also with ‐OH in bamboo and matrix of WPI adhesives. That is to say that a competition exists between urethane formation (covalent bonding of isocyanate with hydroxyl groups in bamboo and matrix in WPI adhesive) and urea formation (isocyanate consumption due to the reaction with water) during the operation of glued bamboo products.

Research limitations/implications

The method of changing reference substance can be used for other DSC samples in which water cannot be conveniently removed, but this method requires that weight of reference substance to be exactly the same as the sample used in DSC measurement. So accuracy of weighing was very important in this DSC measurement.

Practical implications

The method developed in this paper provides a simple and practical solution to studying interactions between WPI adhesive and bamboo by means of DSC.

Originality/value

Changing reference substance was brought forward as a new method of counteracting effect of water in the sample on DSC measurement. The understanding gained through this study could help improve bonding properties of glued bamboo products.

Citation

Cheng, R.X. (2009), "Study on gluing reaction between WPI adhesive and bamboo by means of DSC", Pigment & Resin Technology, Vol. 38 No. 2, pp. 100-104. https://doi.org/10.1108/03699420910940590