Mohs hardness wollastonite

Wollastonite is a form of calcium silicate (CaSiOj). It is a relatively hard (Moh hardness 4.8) white material with needle-like particles. The specific gravity is... 

A general chemical composition of wollastonite is CaO (40-50%), Si02 (40-50%), and minor fractions of Fc203, AI2O3, MgO, MnO, and Ti02. Its specihc gravity (density) is around 2.9 g/cm Mohs hardness is 4.5, specihc snrface area is low, between... 

Wollastonite (CaSiOj), 125,128,129,133,147 Appearance, 147 Aspect ratio, 147 Chemical composition, 147 Color, 147 Density, 147 Mohs hardness, 147 Moisture content, 147 Oil absorption, 147 Particle size grades, 147 Specific gravity, 147 Specific surface area, 147 Surface area, 147 Wood decay fungi, 414 Wood destroying fungi, 83 Wood extractives, 48, 75 Wood fiber, 77, 86, 89, 90, 98, 105, 130 Wood flour, 11, 75, 77, 82, 83, 85, 86, 89, 90, 92, 98, 99, 103-105, 123,129, 130, 131, 133,516... 

The structure of wollastonite is characterized by chains formed from silica tetrahedra connected side-by-side through calcium in octahedral coordination [2]. These chain arrangements account for the formation of acicular crystals and preservation of their shape upon cleavage (Figure 14.1). The moderate value of wollastonite Mohs hardness (4.5-5) is attributed to the high density of the silica chains. In addition to the most important property of acicular shape, the plastics industry places high value on properties such as... 

In selecting wollastonite as the functional filler for plastics, most of the properties to be considered are white color, high brightness, moderate specific gravity, moderate Mohs hardness, moderate range of loose and tapped bulk densities, needle-like particle shape, high processing melt temperature, wide compatibility with silane and titanate surface treatments, and low CLTE. 

Calcium silicate, natural n. CaSiOs. It has white color and acicular particles. It is characterized by high flatting action, combined with low oil absorption, and is used as an extender in paints, ceramics and plastics. Density, 2.9g/cm (24.2lb/gal) O.A., 25—30 particle size, 7 pm (fine particle grade) hardness (moh), 4.5. Syn wollastonite and calcium metasilicate. 

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