The role of the main components of a PVAc-based wood adhesive formulation in the formation and performance of the adhesive joint was investigated. A new analytical methodology was applied to carry out the chemical separation and characterization of the adhesive components present in the bond line. By using extraction techniques on the wet and dry glues it was possible to observe the variation in the solubility of the adhesive components, for different glue formulations. The swollen-state NMR technique proved to be a very useful tool to characterize the insoluble parts present in the adhesive films. These findings, when put into relation to some specific properties of the adhesive joints, contribute to the understanding of the mechanisms involved in the adhesion process.

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Water-redispersible, low-T g acrylic polymer powders are obtained in a free-flowing form by spray drying the structured aqueous dispersions. Powder sticking and caking phenomena are minimized thanks to the heterogeneous particle morphology achieved through a sequential polymerization technique. Redispersibility is reached by the presence of functional monomers containing acid groups, properly distributed in the polymer particles. The influence of the different synthesis parameters on the drying and redispersion processes is discussed. The acrylic powders developed here are well suited for the modification of Portland cement mortars, giving performances comparable to their corresponding "mother" latices.

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Unsaturated alcohols and glycols bearing carboxylic groups were synthesized from maleic anhydride (MA) and alcohols with 2 or 3 hydroxy groups. The halfester monomers were characterized by IR and NMR spectroscopy and were used for the preparation of urethane macroionomers and urethane acrylate graft copolymer latices. Obtained polymers were characterized by solubility and mechanical tests. ZUSAMMENFASSUNG:Ungesattigte Alkohole und Glykole mit Carbonsaure-Gruppen wurden durch Umsetzung von MaleinsBureanhydrid und Alkoholen mit 2 oder 3 Hydroxygruppen hergestellt und durch IR-und NMR-Spektroskopie charakterisiert. Maleinsaurehalbester wurden fiir die Vorbereitung von Urethan-Makroionomeren verwendet. Durch radikalische Polymerisation dieser Ionomeren wurden Acrylat-Pfropfpolymere mit Urethanseitengruppen erhalten, deren Uslichkeit und mechanische Eigenschaften bestimmt wurden.

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