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Formaldehyde emission and high-temperature stability of cured urea-formaldehyde resins
Journal of Wood Science volume 46, pages 303–309 (2000)
Abstract
A test method for measuring formaldehyde from urea-formaldehyde (UF) resins at high temperature was developed and used to assess the influence of the reaction pH on the formaldehyde emission and heat stability of the cured resins. Additionally, solid-state13C CP/MAS nuclear magnetic resonance (NMR) techniques were used to investigate the structure of cured UF resins before and after high temperature heating. Formaldehyde emissions during the cure were related to the UF resins' methylol group content. The heat stability of cured UF resins synthesized under strongly acidic conditions was much higher than that of the other resins, which were prepared in weakly acidic and alkaline media. Solid-state13C CP/MAS NMR spectra showed that formaldehyde emission from cured UF resins after heating is mainly ascribable to decreased methylol groups and dimethylene ether linkages. Significantly, it was revealed that uron structures characteristically found in the cured UF resin synthesized under strongly acidic medium indicated high heat stability.
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Tohmura, S.i., Hse, C.Y. & Higuchi, M. Formaldehyde emission and high-temperature stability of cured urea-formaldehyde resins. J Wood Sci 46, 303–309 (2000). https://doi.org/10.1007/BF00766221
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DOI: https://doi.org/10.1007/BF00766221
Keywords
- Nuclear Magnetic Resonance
- Nuclear Magnetic Resonance Spectrum
- Formaldehyde Emission
- Nuclear Magnetic Resonance Spectroscopy
- Nuclear Magnetic Resonance Study