Sticking It to Formaldehyde

Formaldehyde is toxic, but still widely used to make glues-particularly for the adhesives that hold together plywood. Now a chemist at Kansas State University has come up with a substitute: soy protein-based glue that could, finally, unstick formaldehyde’s dominance in industrial adhesives. A few others have tried using soy protein in glues, but Kansas State chemist Xiuzhi Susan Sun says her batch of adhesives, which use a modified soy protein, are far stronger and more water-resistant than earlier soy-based glues. She says that after soaking in water for 48 hours, plywood held together by the new soy glues showed little or no tendency for the layers to separate. Plywood bonded with other soy glues fell apart. The modified soy protein is not only benign in comparison to formaldehyde, says Sun-it is also cheap and abundant.