Laboratory apparatus for applying air-sprayed powdered adhesive

This work reports on an inexpensive, effective laboratory apparatus for app lying powdered adhesive thermosetting resins in particleboard manufacture. Two percent emulsion wax application on the wood (or agro-fiber) materials prior to 8 percent powdered resin application was the mechanism to assure g ood initial distribution to retain distribution of the powders, thus avoidi ng powdered adhesive sifting during panel layup/assembly transfer prior to hot-press curing. Three powdered adhesive resins were evaluated to manufact ure laboratory southern pine particleboard: urea-formaldehyde, melamine-ure a-formaldehyde, and phenol-formaldehyde. The powdered air-spray apparatus c onsists of a commercially available spray duster (garden insecticide variet y) modified with a pressure gage, control valve (to control application rat e), internal plastic tubing (to deliver the powdered resin into the blender ), and an external plastic tubing (to deliver enhanced distribution air at the apparatus exit into the blender). This apparatus will be of interest to research facilities and machinery designers for resin adhesive application s in laboratories and industrial production.