Chemically reactive organically doped

In the next sections we survey some of the applications of reactive organically doped sol-gel silicas. We return to optics and photophysical applications in Section VI, although historically, the first investigations were concentrated on optics1,20 and it became evident only several years later that the entrapped molecule can also be involved in chemical reactions. 

This book has been divided into three areas chemical detection, biological detection, and decontamination. The subject matter in the chapters include cross-linked divinyl benzene-substituted methacrylate polymers (Chapter 2), porous silicon (Chapter 3), reactive glass surfaces (Chapter 4), polycarbosilanes (Chapter 5), non-aqueous, chemically cross-linked polybutadiene gels (Chapter 6), conducting polyaniline nanofibers (Chapter 7), organically doped polystyrene and polyvinyltoluene (Chapter 8), electroplated polymer cast resins (Chapter 9), self assembled monolayers (Chapter 10), amphiphilic functionalized norbomene polymers (Chapter 11), transition metal substituted polyoxometalates (POMs) (Chapter 12), cross-linked divinyl-benzamide phospholipids (Chapter 13), and silica and organo silyl polymers (Chapter 14). 

These two are quite different in properties the first is propion-aldehyde, formed by certain bacteria and a reactive, acrid-smelling substance the second is the sweet-smelling acetone, familiar as the volatile base of nail varnish and aeroplane dope. The structure and arrangement in space of the molecules of organic compounds is thus critical to their behaviour. Substances (like proprional-dehyde and acetone) whose overall chemical composition is the same but whose structure and shape are different are called isomers. Isomerism is a common occurrence amongst the chemicals of the living body, and we shall meet it frequently. 

Many of the different pillaring agents reported in the literature (organic compounds, metal trischelates, organometallic complexes, metal cluster cations, metal oxide sols, polyoxocations, etc.) have drawbacks such as low reactivity or lack of thermal stability, and polyoxocations are by far the most widely employed. Many different polyoxocations (Al, Ni, Zr, Fe, Cr, Mg, Si, Bi, Be, B, Nb, Ta, Mo, Ti, and, more recently, Cu, Ga, and Ce) have been reported in the open and patent literature and clays with multielement or doped pillars also have been claimed [2,8,9,19,20,68-70,73-75]. However, the chemical composition, structure and charge are at present well defined only for the Al-polyoxocation, in which the Keggin ion [Al,304(0H)24(H20)i2] is identified. 

---