Force surface morphologies

Annis B K, Noid D W, Sumpter B G, Reffner J R and Wunderlich B 1992 Application of atomic force microscopy (AFM) to a block copolymer and an extended chain polyethylene Makromol. Chem., Rapid. Commun. 13 169 Annis B K, Schwark D W, Reffner J R, Thomas E L and Wunderlich B 1992 Determination of surface morphology of diblock copolymers of styrene and butadiene by atomic force microscopy Makromol. Chem. 193 2589... 

Surface morphology Reflection high-energy electron diffraction (RHEED) Atomic force microscopy (AFM)... 

As is known, microscale friction and wear is important in microtribology. However, it is not easy to get real friction force on micro/nano scale during the tests. The surface morphology at nanometer scale, the scanning direction of the FFM, etc., have significant effects on friction force measurement. Even nowadays for commercial SPM we are not quite sure if the friction force we get is a real one or not. 

Puskas, J.E., Antony, P., Kwon, Y., Kovar, M., and Norton, P.R. Study of the surface morphology of polyisobutylene-based block copolymers by atomic force microscopy, J. Macromol. Sci., Macromol. Symp., 183, 191-197, 2002. 

Diblock copolymers PEO-fo-PS have been prepared using PEO macroinitiator and ATRP techniques [125]. The macroinitiator was synthesized by the reaction of monohydroxy-functionalized PEO with 2-chloro-2-phenylacetyl-chloride. MALDI-TOF revealed the successful synthesis of the macroinitiators. The ATRP of styrene was conducted in bulk at 130 °C with CuCl as the catalyst and 2,2 bipyridine, bipy, as the ligand. Yields higher than 80% and rather narrow molecular weight distributions (Mw/Mn < 1.3) were obtained. The surface morphology of these samples was investigated by atomic force microscopy, AFM. 

In addition to surface analytical techniques, microscopy, such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), scanning tunneling microscopy (STM) and atomic force microscopy (AFM), also provide invaluable information regarding the surface morphology, physico-chemical interaction at the fiber-matrix interface region, surface depth profile and concentration of elements. It is beyond the scope of this book to present details of all these microscopic techniques. 

At r > Tr, the relaxation of a non-equilibrium surface morphology by surface diffusion can be described by Eq. 1 the thermodynamic driving force for smoothing smoothing is the surface stiffness E and the kinetics of the smoothing is determined by the concentration and mobility of the surface point defects that provide the mass transport, e.g. adatoms. At r < Tr, on the other hand, me must consider a more microscopic description of the dynamics that is based on the thermodynamics of the interactions between steps, and the kinetics of step motion [17]. 

Higgins S.R., Boram L.H., Eggleston C.M., Coles B.A., Compton R.G., and Knauss K.G. (2002a) Dissolution kinetics, step and surface morphology of magnesite (104) surfaces in acidic aqueous solution at 60°C by atomic force microscopy under defined hydro-dynamic conditions. /. Phys. Chem. B 106, 6696-6705. 

Capillary forces induce morphological evolution of an interface toward uniform diffusion potential—which is also a condition for constant mean curvature for isotropic free surfaces (Chapter 14). If a microstructure has many internal interfaces, such as one with fine precipitates or a fine grain size, capillary forces drive mass between or across interfaces and cause coarsening (Chapter 15). Capillary-driven processes can occur simultaneously in systems containing both free surfaces and internal interfaces, such as a porous polycrystal. 

Determination of the optimal experimental conditions for the atomic force microscopy (AFM) characterization of the surface morphology of a DNA electrochemical biosensor obtained using different immobilization procedures of calf-thymus double-stranded DNA (dsDNA) on a highly oriented pyrolytic graphite (HOPG) electrode surface. 

Fig. 20. Different surface morphologies illustrate limitations in the nanoscopic resolution of the scanning force microscope. a - two rigid spheres, b - two rigid spikes, c - two soft spheres. While Az is the lower limit for the dimple to be resolved by the tip of radius R, d corresponds to the lateral resolution of the SFM tip...

---