METHOD OF MANUFACTURE OF BUILDING MATERIALS ON BASE OF MAGNESIAL BINDER Russian patent published in 2004 - IPC

FIELD: manufacture of building materials and articles on base of magnesial binder. SUBSTANCE: proposed method includes mixing of caustic magnesite powder, mineral additive, super-plasticizer, aqueous solution of magnesium chloride and filler followed by molding and hardening of mixture; first at least part of caustic magnesite powder is activated by joint grinding with super- plasticizer and mineral additive to specific surface of particles of 6000- 10000 sq cm/g, after which is it mixed with remaining said components and additionally with methyl cellulose; relationship of components at joint grinding is as follows, weight-%: caustic magnesite powder, 60-90; super-plasticizer, 0.50-1.50; the remainder being mineral additive and relationship of components in common mixture is as follows, weight-%: activated caustic magnesite powder, 10-50; magnesium chloride solution at density of 1.10-1.31 g/cu cm, 10-35; methyl cellulose, 0.02-0.10; caustic magnesite powder, 0-10; the remainder being filler. During joint grinding, the following components may be additionally introduced: silica white, 3-10 weight-% and alkali-resistant pigment, 0.2-5.0 weight-% and the following components may be introduced into common mixture: copolymer-dispersible powder, 0.5-2.0 weight-%; used as filler is sand of fraction of 0.2-0.7 mm. Filler may consist of mixture of sand and crushed stone; amount of sand in this mixture is 10-50 weight-%. Diatomite may be additionally introduced into common mixture in the amount of 2 to 15 % of amount of activated caustic magnesite powder. Besides that, alkali-resistant pigment may be additionally introduced into common mixture in the amount of 0.2-5% of amount of activated acoustic magnesite powder. Fiber in the amount of 0.025-0.15 weight-% may be introduced into common mixture. Hardening of mixture may be performed at temperature of 10-40 C for 6-20 h and at temperature of 60- 90 C for 1-3 h. EFFECT: enhanced strength of articles. 8 cl, 11 tbl