Analytical and Bioanalytical Chemistry

, Volume 409, Issue 3, pp 763–771 | Cite as

At-line validation of a process analytical technology approach for quality control of melamine-urea-formaldehyde resin in composite wood-panel production using near infrared spectroscopy

  • Roger Meder
  • Wolfgang Stahl
  • Paul Warburton
  • Sam Woolley
  • Scott Earnshaw
  • Klaus Haselhofer
  • Ken van Langenberg
  • Nick Ebdon
  • Roger Mulder
Research Paper
Part of the following topical collections:
  1. Process Analytics in Science and Industry


The reactivity of melamine-urea-formaldehyde resins is of key importance in the manufacture of engineered wood products such as medium density fibreboard (MDF) and other wood composite products. Often the MDF manufacturing plant has little available information on the resin reactivity other than details of the resin specification at the time of batch manufacture, which often occurs off-site at a third-party resin plant. Often too, fresh resin on delivery at the MDF plant is mixed with variable volume of aged resin in storage tanks, thereby rendering any specification of the fresh resin batch obsolete. It is therefore highly desirable to develop a real-time, at-line or on-line, process analytical technology to monitor the quality of the resin prior to MDF panel manufacture. Near infrared (NIR) spectroscopy has been calibrated against standard quality methods and against 13C nuclear magnetic resonance (NMR) measures of molecular composition in order to provide at-line process analytical technology (PAT), to monitor the resin quality, particularly the formaldehyde content of the resin. At-line determination of formaldehyde content in the resin was made possible using a six-factor calibration with an R 2(cal) value of 0.973, and R 2(CV) value of 0.929 and a root-mean-square error of cross-validation of 0.01. This calibration was then used to generate control charts of formaldehyde content at regular four-hourly periods during MDF panel manufacture in a commercial MDF manufacturing plant.


Process analytical technology PAT Near infrared spectroscopy NIR Melamine-urea-formaldehyde resin MUF 



The authors would like to acknowledge Forest and Wood Products Australia Ltd (FWPA) for partial funding under contract PNB169-0809 and for permission to reproduce or adapt the figures and text in this paper.

Compliance with ethical standards

Conflict of interest

The authors also acknowledge no known conflicts in the undertaking and reporting of this study.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  • Roger Meder
    • 1
    • 2
  • Wolfgang Stahl
    • 3
  • Paul Warburton
    • 4
  • Sam Woolley
    • 5
  • Scott Earnshaw
    • 5
  • Klaus Haselhofer
    • 6
  • Ken van Langenberg
    • 7
  • Nick Ebdon
    • 7
  • Roger Mulder
    • 7
  1. 1.Forest Industries Research CentreUniversity of the Sunshine CoastMaroochydore DCAustralia
  2. 2.Meder ConsultingBracken RidgeAustralia
  3. 3.Laminex IndustriesToolara ForestAustralia
  4. 4.Riau Andalan Pulp and PaperPekanbaruIndonesia
  5. 5.MomentiveDeer ParkAustralia
  6. 6.Momentive Specialty ChemicalsMurarrieAustralia
  7. 7.CSIRO Manufacturing FlagshipClaytonAustralia

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