Title
Improving soy protein adhesive with organic montmorillonite for poplar plywood
Authors
CUI JUQING HAN SHUGUANG WANG YAN ZHANG YANG DENG YUHE ZHOU HANDONG ZHU SHANGWU and LU XIAONING

Received May 25, 2014
Published Volume 50 Issue 7-8 July-August
Keywords soy protein adhesive, organic montmorillonite, poplar plywood, shear strength, water resistance

Abstract
A new method to improve a soy protein adhesive by incorporating finely dispersed nanoscale silicate layers from organic montmorillonite was investigated. The results of Fourier transform infrared spectroscopy (FTIR) and small angle X-ray diffraction (XRD) indicated that benzyldimethyl dodecylammonium cations had exchanged with the hydrated ions in the galleries of montmorillonite. The shear strength of poplar plywood was enhanced by about 190% in the presence of 1 wt% organic montmorillonite in the soy protein adhesive. The water resistance of the plywood bonded with the soy protein adhesive also increased, along with the shear strength (above 0.7 MPa), after soaking. The reinforcement and physical barrier offered by the nanoscale silicate layers in the soy protein resin are the main reason for the high shear strength and water resistance of the plywood under study.