Silylated Surfaces

Good,No Highlights,No Markup,all pages are intact, Slight Shelfwear,may have the corners slightly dented, may have slight color changes/slightly damaged spine.

* It has been rumored that a bumble bee has such aerodynamic deficiencies that it should be incapable of flight. Fiberglass-reinforced polymer com posites, similarly, have two (apparently) insurmountable obstacles to per formance: 1) Water can hydrolyze any conceivable bond between organic and inorganic phase, and 2) Stresses across the interface during temperature cycling (resulting from a mismatch in thermal expansion coefficients) may exceed the strength of one of the phases. Organofunctional silanes are hybrid organic-inorganic compounds that are used as coupling agents across the organic-inorganic interface to help overcome these two obstacles to composite performance. One of their functions is to use the hydrolytic action of water under equilibrium condi tions to relieve thermally induced stresses across the interface. If equilib rium conditions can be maintained, the two problems act to cancel each other out. Coupling agents are defined primarily as materials that improve the practical adhesive bond of polymer to mineral. This may involve an increase in true adhesion, but it may also involve improved wetting, rheology, and other handling properties. The coupling agent may also modify the inter phase region to strengthen the organic and inorganic boundary layers.

"Progresses from theoretical issues to applications. Contains a historical overview, in-depth considerations of various scenarios of silica adsorption, and results from the latest research. Invaluable for broad coverage of the expanding field of silica research."

* Much progress has been made in the last 8 years in understanding the theory and practice of silane coupling agents. A major advance in this direction was the measurement of true equilibrium constants for the hydroly sis and formation of siloxane bonds. Equilibrium constants for bond reten tion are so favorable that a silane coupling agent on silica has a thousandfold advantage for bond retention in the presence of water over an alkoxysilane bond formed from hydroxy-functional polymers and silica. In practice, the bonds of certain epoxies to silane-primed glass resist debonding by water about a thousand times as long as the epoxy bond to unprimed glass. Oxane bonds of silane coupling agents to metal oxides seem to follow the same mechanism of equilibrium hydrolysis and rebonding, although equilibrium constants have not been measured for individual metal-oxygen silicon bonds. This suggests, however, that methods of improving bond retention to glass will also improve the water resistance of bonds to metals. of standard coupling agents with a hydrophobic silane or one Modification with extra siloxane cross-linking have improved the water resistance of bonds to glass and metals another hundredfold over that obtained with single coupling agents.

Silicon in Polymer Synthesis gives the first concise overview of silicon used for the synthesis and modification of polymers. The first section gives an introduction to the topic. The subsequent chapters detail the current status both from the basic research as well as from the industrial application points of view.

Sol-Gel Science: The Physics and Chemistry of Sol-Gel Processing presents the physical and chemical principles of the sol-gel process. The book emphasizes the science behind sol-gel processing with a chapter devoted to applications. The first chapter introduces basic terminology, provides a brief historical sketch, and identifies some excellent texts for background reading. Chapters 2 and 3 discuss the mechanisms of hydrolysis and condensation for nonsilicate and silicate systems. Chapter 4 deals with stabilization and gelation of sols. Chapter 5 reviews theories of gelation and examines the predicted and observed changes in the properties of a sol in the vicinity of the gel point. Chapter 6 describes the changes in structure and properties that occur during aging of a gel in its pore liquor (or some other liquid). The discussion of drying is divided into two parts, with the theory concentrated in Chapter 7 and the phenomenology in Chapter 8. The structure of dried gels is explored in Chapter 9. Chapter 10 shows the possibility of using the gel as a substrate for chemical reactions or of modifying the bulk composition of the resulting ceramic by performing a surface reaction (such as nitridation) on the gel. Chapter 11 reviews the theory and practice of sintering, describing the mechanisms that govern densification of amorphous and crystalline materials, and showing the advantages of avoiding crystallization before sintering is complete. The properties of gel-derived and conventional ceramics are discussed in Chapter 12. The preparation of films is such an important aspect of sol-gel technology that the fundamentals of film formation are treated at length in Chapter 13. Films and other applications are briefly reviewed in Chapter 14. Materials scientists and researchers in the field of sol-gel processing will find the book invaluable.

Interfacial Phenomena in Chromatography presents a combination of chromatographic theory, numerical simulation and experimental data. The text covers the interaction and size exclusion methods of separation, identification and characterization of substances in solution. It provides practical information and analysis on the most effective mechanisms of interfacial chromatography, along with its expanding possibilities for biomedical, industrial and environmental applications.