Development of melamine modified urea formaldehyde resins based o nstrong acidic pH catalyzed urea formaldehyde polymer

  • Authors: Hse, Chung-Yun
  • Publication Year: 2009
  • Publication Series: Miscellaneous Publication
  • Source: Forest Products Journal, Vol. 59(4): 19-25

Abstract

To upgrade the performance of urea-formaldehyde (UF) resin bonded particleboards, melamine modified urea-formaldehyde (MUF) resins based on strong acidic pH catalyzed UF polymers were investigated. The study was conducted in a series of two experiments: 1) formulation of MUF resins based on a UF polymer catalyzed with strong acidic pH and 2) determination of the effects of increased melamine content and melamine reaction pH on performance of MUF resins. Formaldehyde emission, internal bond (IB) strength, and thickness swell (TS) of the panels made with the formulated MUF resins were evaluated. UF polymer as backbone structure prepared by strong acidic pH had a significant effect on the overall performance of the MUF resin system. Strong acidic pH was the single most important factor effecting the formaldehyde emission of the panels. Melamine content and melamine reaction pH were evaluated in the final 24 MUF resins prepared in the study. The effects of increased melamine content were significant only for IB strength, but changes in melamine reaction pH in resin preparation resulted in a resin system that had a significant effect on the overall performance of the panels. IB strength increased, formaldehyde emission decreased, and TS decreased as melamine reaction pH decreased from 6.0 to 4.5. These results indicated that the changes in molecular species and resin structure in resin preparation as effected by melamine reaction pH were the most important factors in upgrading the performance of MUF resins. A low melamine content MUF resin was fabricated with formaldehyde (F)/urea (U)/melamine (M) molar ratios of 1.38F/1U/0.055M (melamine content of 6.4%) and reacted under melamine reaction pH of 4.5. This resin produced panels that satisfied the required performance standards of both formaldehyde emission (National Particleboard Association 2-h-desicator test) and IB strength (American National Standard Institute’s IB strength for industrial boards).

  • Citation: Hse, Chung-Yun. 2009. Development of melamine modified urea formaldehyde resins based o nstrong acidic pH catalyzed urea formaldehyde polymer. Forest Products Journal, Vol. 59(4): 19-25
  • Posted Date: August 17, 2009
  • Modified Date: August 17, 2009
  • Print Publications Are No Longer Available

    In an ongoing effort to be fiscally responsible, the Southern Research Station (SRS) will no longer produce and distribute hard copies of our publications. Many SRS publications are available at cost via the Government Printing Office (GPO). Electronic versions of publications may be downloaded, printed, and distributed.

    Publication Notes

    • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
    • Our online publications are scanned and captured using Adobe Acrobat. During the capture process some typographical errors may occur. Please contact the SRS webmaster if you notice any errors which make this publication unusable.
    • To view this article, download the latest version of Adobe Acrobat Reader.