Author(s):
Citation:
Z. Gao, X‐M. Wang, H. Wan, Zhi‐Ming Liu, (2009) "DSC characterisation of urea‐formaldehyde (UF) resin curing", Pigment & Resin Technology , Vol. 38 Issue: 1, pp.3-9, https://doi.org/10.1108/03699420910923526
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The fulltext of this document has been downloaded 597 times since 2009
Acknowledgements:
Abstract:
– The purpose of this paper is to investigate the effects of various catalyst contents, resin solid contents, catalyst species and wood extract on urea‐formaldehyde (UF) curing by differential scanning calorimetry (DSC) technique. The finding obtained would benefit the manufacturers of UF‐bonded composite panels.
– The UF curing rate under each condition in terms of DSC peak temperature was measured by high‐pressure DSC at a heating rate of 15°C/min; the correlations of peak temperature with catalyst content, resin solid content, catalyst species and wood extract, respectively, were regressed via a model equation, which described the curing characteristics of the UF bonding system.
– A model equation, Tp=A · EXP(−B · CC per cent)+D, was proposed to characterise the DSC peak temperatures or the rate of UF curing with regressing coefficients greater than 0.97 (commonly greater than 0.99). The constants A and B in the model equation were found to correspond to kinetic characteristics of UF resin curing reaction. The constant D in the model equation is believed to be associated with the utmost peak temperature, which implies that the DSC peak temperature will finally reach a maximum with catalyst content increasing. It was also found that the wood extracts having higher pH value and base buffer capacity had stronger catalyses on UF curing.
– The catalysts commonly used in medium density fibreboard plants or particleboard plants are those having the utmost peak temperature of about 90‐95°C; the catalyses of wood extracts were much weaker than that of catalyst NH4Cl.
– The model equation could be used to predict the peak temperature or the curing rate of UF resin, and to quantify the effects of wood extracts on UF curing.
Keywords:
Resins, Wood technology, Wood products, Bonding, Composite materials
Type:
Research paper Publisher:
Emerald Group Publishing Limited
Copyright:
© Emerald Group Publishing Limited 2009
Published by Emerald Group Publishing Limited
http://www.emeraldinsight.com/doi/full/10.1108/03699420910923526
Z. Gao (College of Material Science and Engineering, Northeast Forestry University, Harbin, People's Republic of China)
X‐M. Wang (Composite Wood Products, FP Innovations – Forintek Division, Saint‐Foy, Canada)
H. Wan (Composite Wood Products, FP Innovations – Forintek Division, Saint‐Foy, Canada)
Zhi‐Ming Liu (College of Material Science and Engineering, Northeast Forestry University, Harbin, People's Republic of China)
The authors wish to acknowledge Dr Zhiming Liu and Dr Wenhuan Man for their help in the preparation of the wood extracts.
Purpose
Design/methodology/approach
Findings
Research limitations/implications
Practical implications
Published by Emerald Group Publishing Limited
References
- Citation:
- Z. Gao, X‐M. Wang, H. Wan, Zhi‐Ming Liu, (2009) "DSC characterisation of urea‐formaldehyde (UF) resin curing",
Pigment & Resin Technology , Vol. 38 Issue: 1, pp.3-9, https://doi.org/10.1108/03699420910923526 - Downloads:
- The fulltext of this document has been downloaded 597 times since 2009
- Acknowledgements:
- The authors wish to acknowledge Dr Zhiming Liu and Dr Wenhuan Man for their help in the preparation of the wood extracts.
- Keywords:
- Resins, Wood technology, Wood products, Bonding, Composite materials
- Type:
Research paper - Publisher:
- Emerald Group Publishing Limited
- Copyright:
- © Emerald Group Publishing Limited 2009
Published by Emerald Group Publishing Limited - References
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http://www.emeraldinsight.com/doi/full/10.1108/03699420910923526
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