SOURCE:

Faculty: Engineering
Department: Mechanical Engineering

CONTRIBUTORS:

Udeani, F.O;
Achebe, C.H;
Okonkwo, U.C;

ABSTRACT:

The influence of interfacial parameters on the adhesion of pressure sensitive adhesives was investigated. Study on effect of adhesive rheology, interface parameters, surface modification and adhesion strength prediction from correlation between fracture energy/ thermodynamic work of adhesion was done. Research analysis was carried out using concept of physical and practical adhesion approaches. Test liquids Ethylene glycol, Glycerol and Ethanol were used to derive contact angle. Contact angles snapshots for both substrates and adhesives were done using high definition Nikon D80 camera. Low Bond Axisymetric Drop Shape Analysis with Image J software was used to measure contact angle values. Fowkes law was used to calculate surface free energy for both adhesives and substrates. Owendts-Wendt law was employed to calculate thermodynamic work of adhesion. Surface roughness of substrate was evaluated using SRT-6100 surface roughness tester. Characterization of the substrates was done with XMET 700XRF spectrometer. Analytical tools such as Excel and Minitab were used for data analysis.SPSS result showed that 500% of the variation in the polar component of either substrates or adhesives can be attributed to dispersive component of surface free energy. Values of the surface finish obtained, ranged from 0.817mm to 4.412mm.3D Surface Plot graph showed linear, inverse and partial relation for polar and dispersive component of substrates and adhesives. The results obtained concludes that lower adhesion ratio is a product of lower tack, while higher surface finish resulted in higher thermodynamic work of adhesion. A novel way of evaluating adhesion strength without breaking of bond was put forward, through the Adhesion Ratio across the bonds. Application of the research will be vital in oil pipe coating, dental implants, eye drops and pesticides spray for plants.