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1298 Trézl, L. and Pipek, J. (1988): Formation of excited formaldehyde in model reactions simulating real biological systems. J. Mol. Struct.-Theochem 170 , 213

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; automobile tires to improve the bonding of rubber to tire cord; paper to improve the tear strength, especially of wet paper; and alkyds and acrylics to improve their cure. The ability of formaldehyde to form resinous polymers had been observed by chemists in

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in the manufacture of wood-based panels. Urea–formaldehyde (UF) resin is the most widely used polycondensation resins today in wood-based panels industry due to some advantages such as fast curing, good performance in the panel, and cost

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repair. Recently, we have synthesized a novel self-crosslinked terpolymer derived from 4-acetylpyridine oxime, acetophenone, and formaldehyde which was excellent thermal stability and antimicrobial activity for biomedical applications [ 13 ]. Also

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, there is a worldwide concern on the use of formaldehyde due to its suspected carcinogenic effect. For this reason, new technologies are being investigated to modify the traditional tannin–formaldehyde adhesive systems actually used, not only to prevent

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Acta Chromatographica
Authors: Stefano Dugheri, Alessandro Bonari, Ilenia Pompilio, Marco Colpo, Nicola Mucci, Manfredi Montalti, and Giulio Arcangeli

Development of an Innovative Gas Chromatography—Mass Spectrometry Method for Assessment of Formaldehyde in the Workplace Atmosphere S. Dugheri et al. Introduction Formaldehyde (FA), a colorless gaseous

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E. Tyihák , Proc. 2nd Int. Conf. Role of Formaldehyde in Biological Systems, Keszthely, SOTE Press, 1987, pp. 137–144. Tyihák E. Proc. 2nd Int

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Journal of Thermal Analysis and Calorimetry
Authors: G. Vázquez, F. López-Suevos, J. González-Alvarez, and G. Antorrena

Summary  

Phenol-urea-formaldehyde-tannin (PUFT) adhesives have been prepared by copolymerization at room temperature of pine bark tannins with phenol-urea-formaldehyde (PUF) prepolymers prepared under varying operating conditions. Differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) have been used to analyse the curing of prepolymers and adhesives. DSC curves were obtained at three different heating rates and, by means of the Model Free Kinetics isoconversional method, chemical conversion vs. time at a given temperature was obtained. Mechanical conversion was calculated from DMA storage modulus data for those adhesives which gave the best results for plywood and MDF boards.

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Abstract  

Urea-formaldehyde (UF) resins are the most used polycondensation resins today, in manufacturing particleboards. UF resins possess some advantages such as fast curing, good performance in the panel, water solubility and low price. However, the main chemical bonds of the UF resins macromolecules are hydrolysis sensitive. This causes low water and mositure resistance performance and subsequent formaldehyde release from the UF-bonded panels. A multitude of pathways have been explored for the improvement of UF resins’ behavior relating either to their synthesis procedure or application parameters during panel manufacture. In this study, two UF resins (a conventional and an innovative one produced at very low pH and temperature conditions) were analyzed for their specifications and characterized with TG-DTA technique in dynamic heating conditions and FTIR measurements both in their pre-polymer and cured state.

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Fox, C. H., Johnson, F. B., Whiting, J., et al.: Formaldehyde fixation. J. Histochem. Cytochem., 1985, 33 (8), 845–853. Gergely, P., Penke, B., Tóth, Gy.: Organic and

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