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Hybrid inorganic–organic materials based on a methyl methacrylate–n‐butyl methacrylate–methacrylic acid terpolymer have been prepared by the in situ sol–gel process in the presence of tetrabutyltitanate. The whole hydrolysis–condensation process results in homogeneous and semi‐transparent films with amounts of titania ranging from 4.5 to 22%. Infra‐red spectroscopic results show that COO—Ti bonds are formed and that chelating ones are stable up to 200 °C. Thus far, it had not been possible to separate the contributions of the acid groups from the catalyst (acetic acid) and those from the polymer. However, solvent extraction results undoubtedly proved a strong interaction between the polymer and the inorganic phase through COO—Ti bonds. Mechanical properties of the hybrid films have also been investigated through microhardness measurements and dynamic mechanical analysis. The results show that the tensile properties of the composites are strongly enhanced above the glass transition temperature (Tg) of the polymer. Below Tg, the tensile properties are not significantly affected. © 2002 Society of Chemical Industry

This paper presents the anthracological results of Cova de la Guineu. This cave, which is located at the NE of the Iberian Peninsula, has provided charcoal samples from the early Neolithic to the Iberian period enabling the identification of different phases on the basis of flora assemblage interpretation. The results show how Mediterranean forests have been present since the early Holocene stages. At the early phases of the sequence the assemblage records dominant meso-screrophyllous taxa (deciduous Quercus, Taxus baccata), then thermophilous taxa (evergreen Quercus) spread, and finally a late phase of transformation dominated by thermophilous and heliophilous taxa (Mediterranean Pinus). The interpretation and discussion deals with the development and transformation of primary and secondary forests due to human disturbances and climatic variations. The anthracological record from Cova de la Guineu suggests that both elements were important and define the evolution of vegetation during the Holocene in the region.

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