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CRISTOBALITE. The Functional Filler of Choice C.E.D. Process Minerals Technology Review January, 2013. C.E.D. P ROCESS M INERALS , I NC. C RISTOBALITE. A HIGH TEMPERATURE POLYMORPH OF SILICA. OCCURS RARELY IN NATURE.
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CRISTOBALITE The Functional Filler of Choice C.E.D. Process Minerals Technology Review January, 2013 C.E.D. PROCESS MINERALS, INC.
CRISTOBALITE • A HIGH TEMPERATURE POLYMORPH OF SILICA. • OCCURS RARELY IN NATURE. • MANUFACTURES THROUGH A PROPRIATARY, SOLID STATE HIGH TEMPERATURE PROCESS TO CREATE A USEABLE FORM. • CED CRISTOLBRITE AND GORESIL CRISTOBALITE POSSESS A COMBINATION OF PROPERTIES AND CHARACTERISTICS UNIQUELY SUITED FOR APPLICATION AS FUNCTIONAL FILLERS IN ELASTOMERS. C.E.D. PROCESS MINERALS, Inc.
CED Cristobalite Grades C-1 Cristobalite– processed to contain a minimum of 96% cristobalite. Theremainder can be tridymite, quartz or amorphous silica. Product is milled tosizes from 30 mesh to 400 mesh GoreSil– manufactured from C-1 cristobalite. Processed to micron sizesand classified to control particle size distribution. Available in sizes from10µm to 2µm. CristolBrite – Engineeredchemistry to provide high brightness andwhiteness. Higher pH than C1, C-2 and GoreSil. C-2 cristobalite– processed to contain 75% cristobalite. The remainder canbe quartz and tridymite. Same chemical composition as C-1 but lowercristobalite content. C-65 cristobalite– engineered to have 65% cristobalite with the majority ofthe additional phase as quartz. Designed for abrasive application. C.E.D. PROCESS MINERALS, Inc.
The Brightest Idea in Functional Fillers • Very high solar reflectance and thermal emittance • Extremely bright and white • Jointed surface texture • Enhances mechanical bonding with organic polymers • Hydrophobic • Low Moisture Content • Low Oil Absorption • High hardness • High purity silicate mineral • Available in particle sizes from 0.7mm to 2µm C.E.D. PROCESS MINERALS, Inc.
Solar Reflectance and Thermal Emittance Vital to the performance and effectiveness of cool roof products is solar reflectance and thermal transport characteristics combined to minimize heat gain. CED CristolBrite & GoreSil Solar Reflectance = 0.93 Thermal Emittance = 0.88 Solar Reflectance Index =119 C.E.D. PROCESS MINERALS, Inc.
Extremely Bright and White The high temperature transformation of quartz to the silica polymorph, cristobalite, is accompanied by a significant increase in whiteness and brightness. The index of refraction changes from quartz(1.55) to cristobalite(1.48). CED CristolBrite and GoreSil is further modified to optimize brightness. Hunter Brightness: L* = 96 a = 0.1 b = 0.5 C.E.D. PROCESS MINERALS, Inc.
Jointed Surface Texture CristolBrite500x Quartz 500x C.E.D. PROCESS MINERALS, Inc.
Jointed Surface Texture The contrast in surface texture between cristobalite and quartz is illustrated in the pictures on the previous page. Cristobalite has a rounded morphology while quartz fractures exposing acute angles and flat faces. Cristobalite has a low index of refraction and no color tint. Those attributes, coupled with the jointed surface texture – Cristobalite is an excellent titanium dioxide extender C.E.D. PROCESS MINERALS, Inc.
Particle Surface • Hydrophobic and Hydrophilic are frequently used descriptors of surfaces. A surface is hydrophobic if it tends not to absorb water or be wetted by water. A surface is hydrophilic if it tends to absorb water or is wetted by water. More particularly, the terms describe the interaction of the boundary layer with liquid or vapor water. • The surface of most mineral fillers terminate with metal hydroxyl groups and are usually hydrophilic. These surfaces tend to attract moisture and are less compatible with organic polymers. • The surface of CristolBrite and GoreSil terminate with siloxane groups. These surfaces are hydrophobic. The siloxane layer promotes adhesion and increase in mechanical properties in organic polymer systems. C.E.D. PROCESS MINERALS, Inc.
Particle Surface The graph presents the effect of various loading levels of GoreSil on the resistance to scratch in a 100% solids UV polyurethane. Even loading levels as low as 4% have demonstrated significant improvement in scratch resistance C.E.D. PROCESS MINERALS, Inc.
Physical and Chemical Physical PropertiesChemical analysis, Wt% Specific Gravity 2.33 SiO₂ 99.7 Hardness (Mohs) 6.5 Al₂O₃ 0.09 Refractive Index 1.48 Fe₂O₃ 0.04 pH CaO 0.02 CristolBrite 8.5TiO₂ 0.01 GoreSil 6.5 C.E.D. PROCESS MINERALS, Inc.
Particle Size Distribution, µm C.E.D. PROCESS MINERALS, Inc.
Weathering Resistance • Relatively high Solar Reflectance Index • Hydrophobic • Improves resistance to scratching and dirt build up • Non reactive to acids and bases C.E.D. PROCESS MINERALS, Inc.
Thermal Expansion of Cristobalite C.E.D. PROCESS MINERALS, Inc.