Processing and use of carbide lime

A composition comprising:

• (a) 5-60 parts by weight of a filler of powdered dried carbide lime having a calcium hydroxide content of 70-85% by weight and a calcium carbonate content of 5-25% by weight, the calcium carbonate being in the form of surface carbonation on the calcium hydroxide, said carbide lime a waste by-product from the production of acetylene gas by reaction of calcium carbide with water, said filler of powdered dried carbide lime having a moisture content of less than 0.6% by weight, a mean particle size of 5-1 0 microns and a maximum particle size of 25 microns;
• (b) 20-95 parts by weight of at least one thermoplastic material selected from the group consisting of thermoplastic polymer, thermoplastic elastomer and thermoplastic rubber;
• and
• (c) 0-60 parts by weight of at least one additive selected from the group consisting essentially of lubricants;
• stabilizers;
• antioxidants;
• plasticisers;
• pigments and dyes;
• anti-blocking, anti-static, blowing and release agents;
• flame-retardants;
• impact modifiers;
• coupling and wetting agents;
• other processing aids and fibrous reinforcing agents.