Abstract:

The flyash and leached alumino-siliceous residue distilled from a kalisalt from Bayan Obo of Inner Mongolia, with standard sand as aggregate, were used as principal materials to prepare mineral polymer. Quiver moulding method was adopted to manufacture the mineral polymer, and the module was curing at 90 ℃in drying oven. The compressive strength of the products reach up to 78.5 MPa and 89.0 MPa respectively for those cured for 7 days and 28 days. The water content and water absorbability of the representative products were 5.3% and 15.0% respectively, and the mass loss of the product was 2.1% while the specimen was inundated in sulfuric acid solution with a concentration of 1.0 mol/L for 24 hours at 20 ℃. The current experimental results show that the content of leached alumino-siliceous residue distilled from the kalisalt was the primary effective factor on the mechanical properties of the products. High performance mineral polymer can be prepared while the content of sodium silicate in the alkaline liquid and the standard sand in the solid materials are both kept around 70%. During the solidification of the mineral polymer products, both silicate and aluminate oligomers formed by Si—Al materials in the alkaline solution produced aluminosilicate gel by dehydroxy polymerization, then transformed into a three-dimension network structure matrix with Si—O—Al—O bonds, leading to excellent mechanical properties for the mineral polymer products as-prepared in the current study.

Key words: flyash, kalisalt, aluminosilicate, polymerization, mineral polymer