Adhesion morphology effects

As with chemical etches, developing optimum conversion coatings requires assessment of the microstructure of the steel. Correlations have been found between the microstructure of the substrate material and the nature of the phosphate films formed. Aloru et al. demonstrated that the type of phosphate crystal formed varies with the orientation of the underlying steel crystal lattice [154]. Fig. 32 illustrates the different phosphate crystal morphologies that formed on two heat-treated surfaces. The fine flake structure formed on the tempered martensite surface promotes adhesion more effectively than the knobby protrusions formed on the cold-rolled steel. 

Gupta AK, Gupta M, Yarwood SJ, Curtis ASG (2004) Effect of cellular uptake of gelatin nanoparticles on adhesion, morphology and cytoskeleton organisation of human fibroblasts. J Control Release 95(2) 197-207... 

PA/PS blends have been compatibilized through block copolymer formation between amine-terminated PA and anhydride-terminated PS. Anhydride end-groups were introduced into PS through reaction of either anion-terminated PS or hydroxy-terminated PS with trimeUitic anhydride chloride. Park et al. [1992] blended 80 parts PA-6 with 10-16 parts PS and 4-10 parts anhydride-terminated PS in an internal mixer at 240°C. The blends were characterized by torque rheometry, SEM, selective solvent extraction, DSC, morphological stability to annealing, and lap shear adhesion. The effect... 

Another example of static SIMS used in a more quantitative role is in the analysis of extmded polymer blends. The morphology of blended polymers processed by extrusion or molding can be affected by the melt temperature, and pressure, etc. The surface morphology can have an effect on the properties of the molded polymer. Adhesion, mechanical properties, and physical appearance are just a few properties affected by processing conditions. 

Other topics recently studied by XPS include the effects of thermal treatment on the morphology and adhesion of the interface between Au and the polymer trimethylcy-clohexane-polycarbonate [2.72] the composition of the surfaces and interfaces of plasma-modified Cu-PTFE and Au-PTFE, and the surface structure and the improvement of adhesion [2.73] the influence of excimer laser irradiation of the polymer on the adhesion of metallic overlayers [2.74] and the behavior of the Co-rich binder phase of WC-Co hard metal and diamond deposition on it [2.75]. 

In seeking to minimize the contact angle or to promote wetting of the adherend by the adhesive, one must consider the effects both of the chemistry of the components and of the morphology of the adherend surface on the observed contact angle. Finally, comment must be made on the dynamics of the wetting process and the factors upon which it depends. 

Morphological studies of these blends revealed that the compatibilization was very effective in decreasing the interfacial tension and increasing the adhesion between the two phases (Fig. 9). 

The SEM investigation shows that the particle size of the dispersed domain size decreased from 3.3 to 1.1 fxm with the incorporation of 6 wt%, EMA, and this indicates the increased surface area of the dispersed phase morphology. The increase in surface area led to effective compatibilization and is responsible for the increased adhesion strength and tensile impact strength of compatibilized blends. 

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