Calcium carbonate carbon composite physical properties

Li X H, Tjong S C, Meng Y Z, Zhu Q, Fabrication and properties of poly(propylene carbonate)/calcium carbonate composites , Journal of Polymer Science Part B Polymer Physics, 2003 41 1806-1813. 

Typically, in an SMC composition, chopped glass fiber roving (18-75 mm long) is used, and its content can vary fi om about 20-40 wt%. In a BMC composition, shorter glass fiber (6-12 mm. long) is used at 15-20 wt%. In both the SMC and BMC compositions, about 40-60 wt% of an inorganic filler such as calcium carbonate (3 pm) is additionally used, primarily to lower the cost of the composites but also to improve the flame retardancy and other physical properties. 

Lime is made by heating limestone, including chalk, to a temperature between 1100°C and 1200°C in a current of air, at which point carbon dioxide is driven off to produce quicklime (CaO). Approximately 56 kg of lime can be obtained from 100 kg of pure limestone. Slaking and hydration of quicklime take place when water is added, giving calcium hydroxide. Carbonate rocks vary from place to place both in chemical composition and physical properties so that the lime produced in different districts varies somewhat in its behaviour. Dolostones also produce lime however, the resultant product slakes more slowly than does that derived from limestones. 

Calcium carbonate, another widely used filler for both thermoplastic and thermoset resins, is available in a variety of special surface treatments which enhance the wettability by resins to improve the physical properties of the composites to which it is added. 

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