Minerals density

Medium- to heavy-density mineral wool mat with wire netting or expanded metal mechanically secured on one or both sides. Mattress-type products are used for irregular-shaped surfaces and on large pipes and vessels. It is also used as large-cavity fire barriers. 

In contrast to soft biologies, whose mechanical properties primarily depend upon the orientation of collagen fibers, the mechanical properties of mineralized tissues, or hard biologies, are more complicated. Factors such as density, mineral content, fat content, water content, and sample preservation and preparation play important roles in mechanical property determination. Specimen orientation also plays a key role, since most hard biologies such as bone are composite structures. For the most part, we will concentrate on the average properties of these materials and will relate these values to those of important, man-made replacement materials. 

Experimental phase equilibria studies by Campbell and Fyfe (1965) Thompson (1971)and Liou (1971a) indicate an approximate 180°C. lower stability for albite in the presence of quartz and analcite from 12 to 2000 atmospheres pressure. A calculated stability for analcite at 3Kb is about 120°C. (Campbell and Fyfe, 1965), conditions equivalent to rock pressures at 7.5Km depth. However, if water pressure is lower than total, litho-static pressure, the termal stability of a very hydrous, low-density mineral such as analcite can be significantly lowered (Greenwood, 1961). The experimental transformation of alkali zeolites to analcite at 100°C. and 2-3 atmospheres pressures was demonstrated by Boles (1971). The alumina content of the alkali zeolites used in this latter study was found to influence that of the analcite produced, and this independently of the amount of crystalline quartz added to the initial materials. 

In a number of kinetic studies, the reaction rate is not directly proportional to the physical surface area. This discrepancy leads to the concept of the reactive surface area which has been closely linked to the reaction site density and the dislocation density. Theoretical analysis indicates that reaction rates will become directly proportional to defect densities only in highly stressed and deformed minerals. However, experiments using high dislocation-density minerals still produce a low correspondence between reaction rates and total defect density. Energies associated with surface dislocations must be highly heterogeneous and the number of dislocations that actually represent potential reaction sites must be extremely low. 

Inorganic fillers such as calcium carbonate, aluminum trihydrate, etc., are widely used due to their low cost, abundant supplies and ability, after surface treatment, to improve selected resin properties. While inorganic fillers are cheap, the assumption that the lowest-cost filler automatically results in the lowest-cost composite does not always hold true. High-density mineral fillers, while cheap on a weight basis, can be quite expensive on a volumetric basis. 

Abstract A new low density mineral material has been synthesized via a simple, flexible, cheap and easy to control process. This material is a synthetic carbonate produced by carbonation of a solid phase composed of a calcic part and a magnesian part. Typically, its production process includes the calcination of a raw dolomite (general formula CaC03.MgC03) into the oxide form, followed by an at least partial hydration of this oxide and a subsequent carbonation step. This process is thus close to the well-known process used for the production of Precipitated Calcium Carbonate (PCC), a common filler and pigment in plastic, paper and rubber, except that the raw material is a dolomite instead of a limestone. It has to be pointed out that flue gases from different industries can be used as a source of CO2 for the carbonation. 

Thanks to all these properties, the dolocarbonate seems promising for different applications, first of all for all the applications of traditional low density mineral fillers. This material could for instance be used as a component in thermal insulating materials like panels or foams, as a filler in mortars or plasters or concretes to decrease their thermal conductivity, as a filler in polymer or rubber compositions to improve their fire and/or mechanical properties, as a filler in paints, papers, cosmetic compositions, as a rheology modifier (viscosifying agent) in mineral slurries, glues, bitumen or asphalts, polymer compositions, as an ad- or absorbant in different applications such as water or flue gas treatment or even in the field of catalysis, as e.g. a catalyst support, or as a carrier for perfumes, aromas, active substances, medicines... 

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