Rheology control for adhesives based on formaldehyde resins

摘要

Water soluble polymers are incorporated into cellulose adhesives comprising phenol formaldehyde and related formaldehyde resins to impart more resistance to sagging and to increase the open time of the adhesive. A preferred use of the modified adhesive is as an adhesive for assembling engineered wood products such as strand board, particle board, medium density fiberboard, plywood and engineered products such as I-beams. The water soluble polymers achieve the objectives of increased sag resistance and more open time by increasing the viscosity of the adhesive and slowing the loss of water to the cellulose products and the air during use of the adhesive.