Improvement of adhesion between a UV curable fluorinated resin and fluorinated elastomers: Effect of chemical modification onto the mechanical properties of the joints

The present work studies the adhesion of fluorinated polyurethane elastomers through the use of single-lap joints. As an adhesive an innovative fluorinated UV curable acrylic resin able to wet the rubber surface was used. A radical photoinitiator was added to polymerize the resin and to promote covalent bonding between the cured adhesive and the adherends. Moreover the elastomers were modified by introducing chain extenders having either polar OH groups or allylic reactive groups to create covalent bonds at the interface. As a consequence the tensile stress and the breaking energy of the joints increased as a function of the chain extender concentration. Tuning the adhesion strength, joining and assemblying of parts made of highly fluorinated polyurethane elastomers will allow a larger use in the automotive, chemical, oil and aerospace industries.