Self-assembled monolayers and

Section 4.1 briefly describes some of the commonly employed experimental tools and procedures. Chaudhury et al., Israelachvili et al. and Tirrell et al. employed contact mechanics based approach to estimate surface energies of different self-assembled monolayers and polymers. In these studies, the results of these measurements were compared to the results of contact angle measurements. These measurements are reviewed in Section 4.2. The JKR type measurements are discussed in Section 4.2.1, and the measurements done using the surface forces apparatus (SFA) are reviewed in Section 4.2.2. 

Israelachvili and coworkers [64,69], Tirrell and coworkers [61-63,70], and other researchers employed the SFA to measure molecular level adhesion and deformation of self-assembled monolayers and polymers. The pull-off force (FJ, and the contact radius (a versus P) are measured. The contact radius, the local radius of curvature, and the distance between the surfaces are measured using the optical interferometer in the SFA. The primary advantage of using the SFA is its ability to study the interfacial adhesion between thin films of relatively high... 

Johnson and coworkers [6], in their original paper on the JKR theory, reported the measurements of surface energies and interfacial adhesion of soft elastomeric materials. Israelachvili and coworkers [68,69], and Tirrell and coworkers [62, 63,70,88-90] used the SFA to measure the surface energies of self-assembled monolayers and polymer films, respectively. Chaudhury and coworkers [47-50] adapted the JKR technique to measure the surface energies and interfacial adhesion between self-assembled monolayers. More recently, Mangipudi and coworkers [55] modified the JKR technique to measure the surface energies of glassy polymers. All these measurements are reviewed in this section. 

Qian, L. M., Tian, R, and Xiao, X. D., Tribological Properties of Self-Assembled Monolayers and Their Substrates Under Various Humid Environments," Tribol. Lett., Vol. 15, No. 3, 2003, pp. 169-176. 

Senaratne, W., Andruzzi, L. and Ober, C. K. (2005) Self-assembled monolayers and polymer brushes in biotechnology Current applications and future perspectives. Biomacromolecules, 6, 2427-2448. 

As this volume attests, a wide range of chemistry occurs at interfacial boundaries. Examples range from biological and medicinal interfacial problems, such as the chemistry of anesthesia, to solar energy conversion and electrode processes in batteries, to industrial-scale separations of metal ores across interfaces, to investigations into self-assembled monolayers and Langmuir-Blodgett films for nanoelectronics and nonlinear optical materials. These problems are based not only on structure and composition of the interface but also on kinetic processes that occur at interfaces. As such, there is considerable motivation to explore chemical dynamics at interfaces. 

Improved chemisorption methods ( self-assembled monolayers ) and physi-sorption methods (Langmuir-Blodgett films). 

J. M. Tour, L. Jones II, D. L. Pearson, J. S. Lamba, T. P. Bur-gin, G. W. Whitesides, D. L Allara, A. N. Parikh, S. Atre, Self-Assembled Monolayers and Multilayers of Conjugated Thiols, a,co-Dithiols, and Thioacetyl-Containing Adsorbates. Understanding Attachments Between Potential Molecular Wires and Gold Surfaces, J. Am Chem Soc. 1995,112 9529-9534. 

DiBenedetto SA, Facchetti A, Ratner MA, Marks TJ (2009) Molecular self-assembled monolayers and multilayers for organic and unconventional inorganic thin-film transistor applications. Adv Mater 21 1407-1433... 

Self-Assembled Monolayers and Multilayers Derived from Organosilicon Derivatives... 

One of the points made in Schwenz and Moore was that the physical chemistry laboratory should better reflect the range of activities found in current physical chemistry research. This is reflected in part by the inclusion of modem instrumentation and computational methods, as noted extensively above, but also by the choice of topics. A number of experiments developed since Schwenz and Moore reflect these current topics. Some are devoted to modem materials, an extremely active research area, that I have broadly construed to include semiconductors, nanoparticles, self-assembled monolayers and other supramolecular systems, liquid crystals, and polymers. Others are devoted to physical chemistry of biological systems. I should point out here, that with rare exceptions, I have not included experiments for the biophysical chemistry laboratory in this latter category, primarily because the topics of many of these experiments fall out of the range of a typical physical chemistry laboratory or lecture syllabus. Systems of environmental interest were well represented as well. 

Self-assembled Monolayers and Multilayers of Electroactive Thiols... 

SELF-ASSEMBLED MONOLAYERS AND MULTILAYERS OF ELECTROACTIVE THIOLS... 

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