Fundamental aspects of adhesion

Surface analysis has made enormous contributions to the field of adhesion science. It enabled investigators to probe fundamental aspects of adhesion such as the composition of anodic oxides on metals, the surface composition of polymers that have been pretreated by etching, the nature of reactions occurring at the interface between a primer and a substrate or between a primer and an adhesive, and the orientation of molecules adsorbed onto substrates. Surface analysis has also enabled adhesion scientists to determine the mechanisms responsible for failure of adhesive bonds, especially after exposure to aggressive environments. The objective of this chapter is to review the principals of surface analysis techniques including attenuated total reflection (ATR) and reflection-absorption (RAIR) infrared spectroscopy. X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES), and secondary ion mass spectrometry (SIMS) and to present examples of the application of each technique to important problems in adhesion science. 

Silicone adhesives are a generic class of materials encompassing sealants, encapsulants, and PSAs. Sealants and encapsulants were briefly discussed along with other silicone rubbers. Fundamental aspects of adhesion technology in silicones are discussed in a recent chapter by Parbhoo et al.4is Silicone sealants and adhesives are also discussed in a couple of recent publications.436-438... 

Parbhoo, B. O Hare, L.-A. Leadley, S. R. Fundamental Aspects of Adhesion Technology in Silicones. In Surfaces, Chemistry Applications-, Chaudhury, M., Pocius, A. V., Eds. Elsevier Amsterdam, 2002 Chapter 14, pp 677-709. 

In this work, we applied the DPTB method to some fundamental aspects of adhesion on oxide surfaces and validated the approach by comparison with rigorous DPT calculations. In Section 2.2, DPTB results for surface reconstructions on ideal a-Si02 were investigated to serve as a benchmark for surface structures. In Section 2.3, we presented calculations concerning the structures of organic components of the adhesive and introduced a new computational scheme based on QM/MM coupling for surface-adhesive interactions. 

On that basis, the book intends to bridge current issues, aspects and interests from fundamental research to technical apphcations. In seven chapters, the reader will find an arrangement of latest results on fundamental aspects of adhesion, on adhesion in biology, on chemistry for adhesive formulation, on surface chemistry and pretreatment of adherends, on mechanical issues, non-destructive testing and durability of adhesive joints, and on advanced technical applications of adhesive joints. Prominent scientists review the current state of knowledge about the role of chemical bonds in adhesion, about new resins and nanocomposites for adhesives, and about the role of macromolecular architecture for the properties of hot melt and pressure sensitive adhesives. Thus, insight into detailed results and broader overviews as well can be gained from the book. 

Fasi Liang graduated from Sun Yatson University, China, in 1965 as a specialist in Polymer Science. He is a member of the staff of the Shanghai Rubber Research Institute in the People s Republic of China. He spent two years, 1981-1983, at the Institute of Polymer Science, the University of Akron, as a Visiting Scientist, conducting research on fundamental aspects of adhesion. 

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