Effects of Nanoclay Modification with Aminopropyltriethoxysilane (APTES) on the Performance of Urea–formaldehyde Resin Adhesives

Abstract

Urea-formaldehyde (UF) resins, as the most common adhesives for wood-based composites, emit formaldehyde, which is forcing producers to find a solution to this problem. Using scavengers is a practical way of reducing formaldehyde emissions, but sometimes these materials change the properties of the adhesive. This study investigated the effect of adding nanoclay and nanoclay modified with aminopropyltriethoxysilane (APTES), as scavengers, on the formaldehyde emission and the properties of the urea-formaldehyde resin. Modification of nanoclay with APTES was confirmed by Fourier transform infrared (FTIR) and X-ray diffraction (XRD) analysis. After the addition of nanoclay and modified nanoclay to the urea-formaldehyde resin, the emission of formaldehyde decreased by 22% and 61%, and the physical and mechanical properties were improved. The FTIR, XRD, and differential scanning calorimetry results showed that the addition of nanoclay and modified nanoclay improved the characteristics of the adhesive, reduced the crystalline areas, and delayed the curing of the adhesive. Additionally, according to thermogravimetric analysis results, addition of nanoclay and modified nanoclay increased the thermal stability and reduced the weight loss of urea formaldehyde resin.