Test MethodAssessment of adhesion between polyurethane liner and epoxy based substrate: Methodology and experiment

A methodology for assessing interfacial adhesion properties between polyurethane liners and epoxy based substrates was sought to optimize manufacturing procedures for polyurethane lined fibre reinforced epoxy piping. The experimental study showed that the blister test is apposite and expedient for this purpose. The employed methodology allowed for quantification of bond toughness by pressurizing a polyurethane overlayer through a central perforation in an epoxy substrate and measuring the height and pressure of the resulting blister during interfacial fracture. Details of sample fabrication, experimental setup and testing procedures are presented. This study demonstrated that specimens with mechanically bonded polyurethane-epoxy interface underwent interfacial fracture. Samples with a strong chemical bond at the interface, on the other hand, did not exhibit interfacial fracture. A chemically bonded interface is, thus, deemed superior to its mechanically bonded counterpart, and manufacturing protocols for polyurethane lined fibre reinforced epoxy pipe should, therefore, be adjusted to promote chemical bonding at the materials' interface.