# Modification of Urea-Formaldehyde Resin with Triethylenetetramine: Effect on Adhesive Properties and Plywood Strength

## TL;DR

Adding small amounts of TETA to urea-formaldehyde resin reduces formaldehyde emissions from plywood but slightly lowers its strength.

## Contribution

The study introduces TETA as a formaldehyde scavenger in UF resin to reduce emissions while maintaining acceptable plywood performance.

## Key findings

- TETA increased adhesive pH and gel time without affecting viscosity or solids content.
- Formaldehyde emissions from plywood decreased with TETA addition.
- A 0.5% TETA formulation was optimal for balancing emission reduction and mechanical performance.

## Abstract

Due to its multiple amino groups, triethylenetetramine (TETA) can be used as an effective formaldehyde scavenger contributing to the reduction in formaldehyde emission from plywood. This study aimed to evaluate the effect of small TETA loadings on the properties of urea-formaldehyde (UF) resin and the performance of the resulting plywood. Adhesive mixtures containing 0%, 0.5%, 1.0%, and 1.5% TETA were prepared and characterized in terms of pH, viscosity, solids content, and gel time. The incorporation of TETA significantly increased adhesive pH and gel time, while viscosity and solid content were not significantly affected. The analysis of formaldehyde content and spectroscopic and thermogravimetric analyses of the cured adhesives showed reduced formaldehyde content, changes in chemical structure, and enhanced thermal stability at lower temperatures but accelerated degradation at higher temperatures. Formaldehyde emission from plywood was reduced; however, bonding quality and mechanical performance decreased with higher TETA content. Nevertheless, the wet shear strength of all variants exceeded 1 N/mm2. Adhesive formulation containing 0.5% TETA was selected as the optimal variant, providing environmental benefits while maintaining satisfactory plywood performance.