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plastic waste: recycling of the boardThe increasing obligation to manage and to recycle industrial and municipal solid waste leads to the developing of new recycled products. In this paper, the possibility to make boards from wood residues and plastic waste (weight-to-weight ratio: 3:1), has been studied. They are obtained by simpIy heating and compressing. The mechanical tests show that the resistance to static bending are close to those of commercial particleboards. The dimensional stability of recycled wood-plastic composites appears to be particularly encouraging compared to traditional boards. Furthermore, the thermoplastic nature of the waste materials used allows the recycling of the resultant waste, or of the products once at the end of their useful life: tests of runs of successive recycling without any additional supply show a slight decrease in the mechanical properties of the boards obtained, when compared to the original boards. Untersuchungen zur Herstellung von Platten aus Holz-und Kunststoffabfi~llen: Biegefestigkeit, Dimensionsstabilit~t und Wiederverwertung der PlattenDie steigende Verpflichtung, industrielle und kommunale Abffille wiederzuverwerten ffihrt zur Entwicklung neuer Produkte. In dieser Studie wird die M6glichkeit untersucht, Platten aus Holz-und Kunststoffresten im Verh~iltnis 3:1 herzustellen. Die Platten wurden einfach durch Erhitzen und Verpressen hergestellt. Ihre statische Biegefestigkeit lag nahe der yon kommerziellen Spanplatten. Die Dimensionsstabilit~it erscheint vielversprechend im Vergleich mit traditionellen Platten. Dariiberhinaus erlaubt das thermoplastische Verhalten der Abfiille sowohl eine Wiederverwendung der Reste bei der Herstellung als auch der produzierten Platten nach ihrem Gebrauch. Nach mehrmaliger Wiederwertung solcher Platten ohne sonstige Zus~itze ergab sich eine nur geringfiigige Abnahme der mechanischen Eigenschaften.

Non-isothermal and isothermal thermomechanical analysis (TMA) of the cross-linking and hardening of wood joints bonded with urea-formaldehyde (UF), melamine-urea-formaldehyde (MUF), and phenol-melamine-urea-formaldehyde (PMUF) resins was carried out, allowing the determination of the variation of physical properties of these thermosetting adhesives in situ in the wood joint. Gelling temperature, hardening and vitrification temperature and temperature at which relative elastic moduli reach their maximum were also determined for wood joints obtained with the three resins. Deductions as regards rates of hardening, influence of amount of hardener and of curing temperature are reported on the basis of the measured TMA variation of the relative elastic moduli of the joints assemblies.