Resin Distribution in Medium Density Fiberboard. Quantification of UF Resin Distribution on Blowline-and Dry-Blended MDF Fiber and Panels
Keywords:
Medium density fiberboard, urea formaldehyde resin, confocal microscopy, resin visualization, resin distributionAbstract
A novel technique has been developed for visualizing urea formaldehyde (UF) resin distribution on fibers and within MDF panels. A fluorescent label was chemically bound to the resin, and digital images of resinated fiber, generated via confocal laser scanning microscopy (CLSM), were analyzed. Results indicate that this technique can be used to quantify UF resin coverage and distribution as well as provide information on resin film thickness on MDF fiber before pressing and in panels. The technique can distinguish between different methods of resination and was employed to determine that these processes can result in different surface coverages of UF resin on MDF fiber. Resin injected at the end of the blowline gave significantly less resin coverage of fiber than that which was injected at the start of the blowline. UF resin droplets were also relatively thicker and less dispersed when injected at the end of the blowline. Visualization of UF resin also illustrated resin distribution changes upon pressing of fiber particularly in the presence of wax. This result has important implications for future studies targeting optimization of resin deposition, since the droplet size distribution, as applied to the fiber, may not correspond to the droplet size distribution of resin in the panel.References
Albritton, R. O., P. H. Short, and D. E. Lyon. 1978. Optical evaluation of resin coverage on fiber furnish. Wood Fiber9(4):276-281.nButterfield, B., K. Chapman, L. Christie, and A. Dickson. 1992. Ultrastructural characteristics of failure surfaces in medium density fiberboard. Forest Prod. J.42(6):55-60.nDonaldson, L. A., and T. D. Lomax. 1989. Adhesive/fiber interaction in medium density fiberboard. Wood Sci. Technol.23(4):371-380.nEde, R. M., A. Thumm, B. A. Coombridge, and G. S. Brookes. 1998. Visualization and quantification of wax on MDF panels: A comparison of emulsion and molten waxes. In Proc. Washington State Particleboard Symposium, Pullman, WA.nFeng, M. W., and T. Hutter. 2001. Detection and measurement of UF resin distribution in MDF. In Proc. 5th European Panel Products Symposium, October 10-12, 2001, Llandudno, United Kingdom.nGrigsby, W. J., and A. Thumm. 2003. Visualization of UF resin on MDF fiber by XPS imaging. Holz Roh-Werks, Manuscript Submitted.nFeng, M. W., A. M. McDonald, A. Thumm, and C. Loxton. 2003. X-ray photoelectron spectroscopy determination of resin coverage on MDF fiber. Holz Roh-Werks. Manuscript Submitted.nKamke, F. A., C. A. Lenth, and H. G. Saunders. 1996. Measurement of resin and wax distribution on wood flakes. Forest Prod. J.46(6):63-68.nKamke, F. A., H. Sizemore, K. A. Scott, J.-B. Ra, and C. J. C. Kamke. 2000a. Advances in adhesive detection and measurement in panel products. In Proc. 4th European Panel Products Symposium, October 11-13, 2000, Llandudno, United Kingdom.nKamke, F. A., K. A. Scott, J.-B. Ra, and C. J. C. Kamke. 2000b. Measurement of resin distribution in MDF fiber. In Proc. Wood Adhesives 2000, June 22-23, 2000, Lake Tahoe, Nevada. Forest Products Society, Madison, WI.nMcLaughlan, J. M. 1996. New methods for advancing MDF research in the laboratory. In Proc. 30th Int. Symp. Particle/Composite Materials. April 16-18, Pullman, WA.nMurmanis, L., G. C. Myers, and J. A. Youngquist. 1986. Fluorescence microscopy of hardboards. Wood Fiber Sci.18(2):212-219.nThumm, A., and W. J. Grigsby. 2002. Interaction of wax and UF resin in MDF: Qualitative analysis of the relationships between wax and resin on MDF fiber. In Proc. 6th European Panel Products Symposium, October 9-11, 2002, Llandudno, United Kingdom.nThumm, A., A. G. McDonald, and L. A. Donaldson. 2001. Visualization of UF resin in MDF by cathodoluminescence/scanning electron microscopy. Holz Roh-Werks.59:215-216.nYoungquist, J. A., G. C. Myers, and L. L. Murmanis. 1987. Resin distribution in hardboard: Evaluated by internal bond strength and fluorescence microscopy. Wood Fiber Sci.19(2):215-224.n
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