Ultrasonic Atomization of pMDI Wood Resin
Keywords:Ultrasonic atomization, droplet size and size distribution, pMDI resin
AbstractA novel, patent-pending approach to the application of wood resins based on an ultrasonic principle was developed in this study. Liquid polymeric methane diphenyl-diisocyanate (pMDI) resin was successfully atomized using a bench-scale 25 kHz ultrasonic atomizer. The optimal average sizes of the resin droplets generated at a flow rate of 0.7 mL/min and power input of 5.0 J/s were about 90 μm. In addition to fewer fine droplets than that produced by conventional spinning-disk atomizers, the droplets of pMDI resin produced by the ultrasonic atomizer had a more uniform droplet size distribution. These results indicate the potential advantages of implementing ultrasonic atomization in oriented strandboard production, including elimination of the hazardous fraction of fine resin droplets and potential production cost savings from improved resin efficiency. The ultrasonic atomization of wood resins appears to be a promising alternative to the spinning-disk atomizer.
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