| 摘要 |
Shaped products (e.g. sheets) comprising a matrix of water-insolubilised organic polymeric material (such as hydrolysed vinyl acetate polymer) filled with set hydraulic cement, as described for example in European Patent Publication 55 035 (ICI), have an unusually high flexural strength, above 40 MPa, but this falls considerably when the products are heated above about 250 DEG C. By the invention, the extent to which flexural strength of such products is lost when they are heated is reduced, by first heating to burn out the organic polymeric material, and then bringing the product into contact with water to form a set cement in the interstices left by the burnt-out material. |
