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FTIR spectroscopy was used to distinguish between beech (Fagus sylvatica L.) trees grown at five different sites; one in middle Germany close to Göttingen (forest district Reinhausen), three located in the southwest (two in Rhineland-Palatinate: forest districts Saarburg and Hochwald, and one in Luxembourg), and one in North-Rhine Westfalia. Detailed investigation of the spectra in the fingerprint region (1800–600 cm-1) revealed 16 distinct peaks and shoulders, most of which were assignable to wavenumbers previously shown to represent wood compounds. Differences in peak heights and peak ratios indicated differences in wood composition of beech trees from different sites. To determine if the wood of individual trees could be distinguished, principal component analysis (PCA) and cluster analysis were performed using FTIR spectra as input data. With both PCA and cluster analysis, trees from four of the five different sites were separated. It was not possible to distinguish between trees from Saarburg and Hochwald, where similar edaphic and climatic conditions exist, while wood spectra from trees from all other areas clearly segregated. Wood collected at different positions in the stem (bottom, crown, center and outer year rings) of trees grown at the same site was not distinguishable. Therefore, FTIR spectral analysis in combination with multivariate statistical methods can be used to distinguish wood of trees from different growth habitats. Extension of this method to other species may be of great interest for wood certification, as it may be possible to distinguish wood, of a given species, originating from different regions.

Fourier transform infrared attenuated total reflectance (FTIR-ATR) spectroscopy was combined with multivariate data analysis to investigate the chemical changes in wood during particle- and medium density fibreboard (MDF) production of grand fir (Abies grandis [Douglas ex D. Don] Lindl.) and European beech (Fagus sylvatica L.). The mechanical and technological properties of the novel particle- and fibreboards from beech or grand fir wood were similar to those of conventional panels from pine and spruce. This indicates that these timbers can be used as resources for wood-based panel production. Principal component analysis of FTIR spectra differentiated wood, fibres, particles, MDF, and particleboards of both species in the whole production process. Modifications in the spectra of fibres and particles suggested that cellulose properties of wood were changed during mechanical pulping. Different binders and hydrophobic additives were clearly traceable and discernable in wood composites. Samples from the same production step were clustered together, indicating high homogeneity of the raw materials, and intermediate and final products, respectively. This suggests that FTIR spectroscopy in combination with cluster analysis is a useful tool to assess product quality and can be further developed to control and optimize production processes for innovative wood-based panels.

Efficient end-of-life solutions play an important role in developing sustainable packaging because they contribute to reducing resource wastage and environmental impact, whilst providing economic and social benefits. This paper briefly reviews current end-of-life solutions for fibre and bio-based materials for packaging in Europe. It also addresses current research in the field, as well as standardization, legislation and socio-economic aspects related to renewable packaging in Europe. This review focuses on the following groups of packaging materials: paper and board and bioplastics. With this hierarchy, recycling, organic recovery and energy recovery are analysed with regard to the processes and technologies that offer the most sustainable end-of-life options.

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A method is described that enables the alternated total reflectance infrared (ATR-IR) spectroscopy of thin-layer samples deposited onto one side of an exchangeable silicon wafer, the uncoated side of which is pressed against a small-area diamond single-reflection element. The pressing device is designed as a hollow spindle with a small ring-shaped opening at the end facing the wafer; thus, the sample spot involved in the measurement remains undisturbed. The sample can be UV-irradiated, and the atmosphere above it can be flushed with an inert gas introduced through the hollow spindle. The performance of the method is illustrated by the investigation of the influence of pressing force on background and on absorption band areas. With a commercial real-time Fourier transform infrared (FT-IR) spectrometer, the measurement of the UV-polymerization kinetics following the vanishing of the double bounds is demonstrated for a few thin-layer samples that were deposited on silicon wafers by spin-coating or by the Langmuir–Blodgett technique.

ZUSAMMENFASSUNG:Die SUMMARY:Shaping in the nip of the calender is characterized by the presence of a spindle-shaped bead of superfluous melt, i.e. bank, front of the nip. The melt transported to the nip by the drag set up by the rolls is then subjected to partial change in flow. The rerouted melt flows into the bank and is replaced by melt transported from the bank into the nip. The currents at the interior of the bank are also governed by its outer movement, a rotating movement, which is superimposed by a spiral undulation, and this decisively affects the quality of the film. The bank is formed by the melt which is severely sheared * Vorgetragen auf der PVC-Diskussionstagung des Deutschen Kunststoff-Instituts in

The possibility of a quantitative IR spectroscopic determination of the mass or thickness of Langmuir−Blodgett (LB) layers directly deposited onto a multiple internal reflection (MIR) element has been investigated. The thickness is calculated from the absorbance (band area) ratios obtained for the LB layer and for a bulk layer of either comparable or a much greater thickness. The basic relations describing the absorbance for different kinds of partial covering of a trapezoidic MIR element are summarized:  for the double-sided deposition using the LB technique, for the one-sided deposition of a thin layer achieved by dropping a solution, and for the one-sided deposition of a thick layer. The experiments were performed with octadecyl methacrylate on ZnSe and Ge. A relation is given for the number of reflections for the two-sided covering of the reflection element, typical for the LB technique. The investigations covered all bands in the range from 700 to 2930 cm-1. The set of equations for the absorbances is supposed to be helpful also for the evaluation of other quantitative analysis using the MIR technique.