Ceramic-like products

The cultural history of ceramics mainly deals with making pottery, the oldest craft on which continuous knowledge is available. Of course this knowledge has increased over the years, but in numerous places in the world pots are still being made in a way which hardly differs from the methods which were applied thousands of years ago. This is also true for the production of non-cultural ceramics, like for example bricks. 

ARCILLA RESEARCH is a small, Dutch-based, technology enterprise which has developed a special body of techniques and materials based on a mineral binder system, whereby products with ceramic-like properties are cured rather than fired. In partnership with industry, university and government institutions, Arcilla is developing innovative products and systems to meet high technical specifications and which impact upon the environment, physical resources and mass needs. The mineral binder system and range of new materials are neither cements nor ceramics yet offer many of the advantages of both. Three units have... 

Micronization of our antifungal using the favored Jet pulverizer micronizer (Figure 17) led to the desired particle size product however, the micronizer Venturi feed mechanism rapidly (1-3 min) became clogged by a ceramic-like coating on the... 

Perhaps plans have not heen formulated in several cases, or results disseminated. The avenues of research that the identification of a natural product may open are many, so that in the true sense these compounds may be considered allelochemic (J )as opposed to strictly allelopathic. For example, the discovery of a novel biologically active natural product logically presupposes that the metabolic pathway will eventually he elucidated, that possible synthesis, or partial synthesis may be attempted, that homologs and analogs will be described and that other areas may be considered for eventual employment of these materials, not only in more obvious uses such as pesticides, hut also medicinal and non-biological areas. An example of a non-biological use is that of orlandin ( ) which is denatured in acetone to produce an acid and base resistant product which is ceramic-like and is not soluble in organic solvents. 

Geopolymers are another type of intermediate products that lie between cements and ceramics [7]. A geopolymer is made by pyroprocessing naturally occurring kaolin (alumina-rich clay) into metakaolin. This metakaolin is then reacted with an alkali hydroxide or sodium silicate to yield a rock-Uke hard mass. Thus, a chemical reaction, which is not fully understood, is employed to produce a hard ceramic-Uke product. Though this product is produced like cement, its properties are more like a sintered ceramic. It is dense and hard like a rock. 

Paper of course is perhaps the most commonplace example of a fibrous product. Although most common paper products are made of cellulosic fibers, paper-like products can also be made from the so-called high performance fibers such as aramid, glass, carbon, or other ceramic fibers. 

Ceramic-type products such as supercalcine and glass ceramics have been subject to a crystallization process and are therefore thermodynamically more stable. Consequently, as long-term structural changes are less likely with those solidification products, they may maintain their original properties at a higher temperature than glasses. 

The EPA may be moving away from the position that the constituents of ceramic materials and other statutory mixtures do not need to be on the Inventory. In a 2008 letter from the EPA to the American Chemistry Council, the EPA took the position that chemicals created during the formation of ceramic materials must be listed on the Inventory. 113 The EPA gave the specific example of ceramic-like materials that are made using relatively precise stoichiometric and compositional control, and result in products with definite elemental ratios, and unit cell structure and atomic coordination sites. These ceramic-like materials should be given chemical names rather than use the broader term ceramics. ... 

As solid wastes are becoming a matter of increased world concern due to their amoimt as well as difficulty and cost of final disposal, ceramic products can well supply as matrices for industrial residues incorporation snch as giving an option for the solid waste disposal with a possible increase in the properties of the clay ceramic products. The incorporation of wastes from several industrial activities is a technological alternative to reduce the environmental impact due to their indiscriminate disposal. One such measure is the waste incorporation into intensive-produced clay ceramics like bricks and tiles (Parsons et al., 1997). This incorporation is now a common practice and benefits both, the industry... 

The forecasts made in 1985 (77) of 8—8.5% worldwide aimual growth have not materialized. The 2 x lOg + /yr engineering plastic production reported for 1985—1986 has remained fairly constant. Whereas some resins such as PET, nylon-6, and nylon-6,6 have continued to experience growth, other resins such as poly(phenylene oxide) have experienced downturns. This is due to successhil inroads from traditional materials (wood, glass, ceramics, and metals) which are experiencing a rebound in appHcations driven by new technology and antiplastics environmental concerns. Also, recycling is likely to impact production of all plastics. 

In the thermal production of gold coatings on ceramics and glass, paints are used which comprise Au chloro-complexes and sulfur-containing resins dissolved in an organic solvent. It seems likely that polymeric species are responsible for rendering the gold soluble. 

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