Synthesis of polybutadiene-acrylates and properties of the photocured films

The acrylation of polybutadienes was performed by reaction of acrylic acid with epoxy, epoxy-hydroxyl functionalized and hydroxyl-terminated oligomers. Some epoxy-functionalized oligomers were previously obtained by epoxidation of a liquid 1,4-polybutadiene. The properties of the acrylated products were affected by the oligomer type and the reaction procedure. The UV-curing of these products was studied by FTIR and thermal analyses, which showed the amorphous and rubbery nature of the resulting films. In some cases, the double bonds conversion was increased by a thermal post-curing, but the adhesion properties were strongly reduced. The swelling of the UV-cured films was studied by varying the solvent polarity. The mixtures of some polybutadiene-acrylates with a typical epoxy-acrylic resin gave highly cross-linked films showing a flexibilizing effect due to the polybutadiene oligomers which can act as reactive diluents.