Hydratisiertes Magnesiumcarbonat

摘要

The invention comprises hydrated magnesium carbonates, where x is a number from 5 to 7 and y is an integer from 9 to 13. The compounds may be made by addition of CO2 to a slurry of Mg(OH)2 in water until a pH of from 7.5 to 9.0 is reached, separating the solids from the slurry and drying them at below 70 DEG C. The CO2 may be introduced into the slurry by spraying gas mixtures containing CO2, or by addition of solid CO2. Thermal decomposition curves of (MgCO3)3 Mg(OH(2.3H2O and (MgCO3)3.Mg(OH)2.10H2O are shown.ALSO:The invention comprises polymeric compositions and insulating materials containing hydrated magnesium carbonates, where x is a number from 5 to 7 and y is an integer from 9 to 13. Example (2) relates to the preparation of a polyurethane foam containing (MgCO3)3.Mg(OH)2.10H2O. This carbonate is mixed with glycol-adipic acid polyester and the mixture is reacted with naphthalene diisocyanate. Water is added resulting in foaming of the mix. Example (4) relates to chlorosulphonated polyethylene, to which (Mg-CO3)3. Mg(OH)2.10H2/O, titanium dioxide, calcium carbonate, and magnesium oxide were added, the mixture being passed through rolls to form sheets which are vulcanized. Example (3) describes the preparation of an insulating material by addition of (MgCO3)3.Mg(OH)2. -10H2/O to asbestos fibre, diatomaceous earth, blast furnace slag, and Na2CO3 to form a mixture which is slurried with water, the slurry being heated to 105 DEG C. to form a cellular material. This material is broken up into lumps to be compressed in a mould into any desired shape.ALSO:A refractory surface is coated with a solution consisting of 20% acetone and 80% polyvinyl alcohol. The article is vacuum-dried at 30 DEG C. and 0,5 p.s.i.a. for 5 hours.