Inorganic Polymer Glasses

From crystalline to amorphous (particle) hydrates inorganic polymers, glasses, clays, gels and porous media... 

Next to homogeneous reaction conditions, multi-phase or heterogeneous polymerisation conditions frequently occur. Suspension and emulsion polymerisation are examples, but also condensation polymerisation with phase separation of water during cure. The low-temperature production of inorganic polymer glasses (IPGs) is a special case of suspension polymerisation involving clay particles in a reactive silicate solution. 

Figure 2.6. Production of an inorganic polymer glass (IPG) for a metakaolinite (Mk) particle size of 1.8 /xm at 35°C (a) non-reversing heat flow and storage modulus (b) heat capacity and...

Table IL Advantages and Disadvantages of Inorganic Polymers (Glass)...

The well-known thermal stability of most minerals and glasses, many of which are themselves polymeric, has led to intensive research into synthetic inorganic and semi-inorganic polymers. These materials can be classified into the following groups ... 

Enzymes can be immobilized by matrix entrapment, by microencapsulation, by physical or ionic adsorption, by covalent binding to organic or inorganic polymer-carriers, or by whole cell immobilization (5 ). Particularly impressive is the great number of chemical reactions developed for the covalent binding of enzymes to inorganic carriers such as glass, to natural polymers such as cellulose or Sepharose, and to synthetic polymers such as nylon, polyacrylamide, and other vinyl polymers and... 

Filaments, or fibrils, are similarly variable in size. When the terms refer to portions of a fiber, their dimensions are also usually unspecified but are relative to the fiber itself. Fibrils of glass or inorganic polymers that have been measured are often less than 10 nanometers in diameter and form bundles of aligned fibrils 0.2 to 10 micrometers in diameter and up to 100 micrometers in length (Ray, 1978). Occasionally, minerals with diameters of a few millimeters and lengths of hundreds of centimeters have been described as fibrous. Most objects called fibers, however, are microscopic, with maximum dimensions of less than a millimeter. 

Just as silicon dioxide forms the basis of glass, so also does it form the basis of many of the rocks, grains of sand, and dirt particles that compose the earth s crust. Most rocks are inorganic polymers, but here we will deal with only a few of these containing significant amounts of silicon. 

The most commonly used column support materials are made from diatomite. Other materials include sand. Teflon, inorganic salts, glass beads, porous layer beads, porous polymers, carbon blacks, etc. We will discuss the diatomite supports in some detail and additional information may be obtained in Chapter 3. 

POLYETHERS - TETRAHYDROFURAN AND OXETANE POLYMERS] (Vol 19) -in organic-inorganic hybrids [GLASSES, ORGANIC-INORGANIC HYBRIDS] (Vol 12)... 

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