摘要:
The invention relates to dimethylphosphinylalkanephosphonic acids of the general formula I, in which n is 1 or 2, which are used as setting retarders for gypsum. ##STR1##
摘要:
Gypsum and anhydrite plaster is improved by adding at least one alkylene diphosphonic acid or water soluble salt thereof, represented by the following formula: ##STR1## wherein X is hydrogen or lower alkyl of 1-4 carbons, Y is hydrogen, hydroxy or lower alkyl of 1-4 carbons, and n is 1-10. The plaster is found to have an increased finishing time, while the quantity of water necessary is reduced and the mechanical strength of the finished plaster is improved.
摘要:
This invention relates to a novel means of manufacture of gypsum board. The improvement herein comprises the use of sodium and/or ammonium salts of ethoxylated, sulfated alcohols as foaming agents, said alcohols being a mixture of primary, linear alcohols having an average chain length of 9 carbon atoms.
摘要:
The water resistance of gypsum products, such as gypsum wallboard, is improved by incorporating in the composition from which the gypsum product is made polyvinyl alcohol and wax-asphalt emulsion.
摘要:
SET RETARDING AGENTS AND SYSTEMS FOR PLASTER INCLUDING: POLYCARBOXYLIC ACIDS, PARTICULARLY 1,3,5-PENTANE TRICARBOXYLIC ACID; LOW MOLECULAR WEIGHT POLYAMINE REACTION PRODUCTS THEREOF; COMBINATIONS OF THESE WITH A CHELATING OR COORDINATION AGENT; AND/OR COMBINATIONS OF ANY OF THE ABOVE WITH BORIC ACID OR BORAX.
摘要:
A method for sheet forming a remarkably waterproof gypsum hardened body, in which a main component consisting of gypsum dihydrate, slag and calcium hydroxide and additives are added with a part of the main component coated with a hydrophobic diorganopolysiloxane fluid having a kinetic viscosity of 10-10,000 CS at 25.degree. to be sheet formed and cured. The hydrophobic diorganopolysiloxane fluid is uniformly dispersed through the sheet formed gypsum hardened body and its strong water repelling property makes the gypsum hardened body remarkably waterproof to be used suitably as both interior and outdoor construction materials.
摘要:
The present invention provides a gypsum molded product having excellent waterproof properties without impaired strength by adding alkaline metal alkylsiliconates or phenylsiliconates together with calcium hydroxide or calcium oxide to gypsum; poly(.alpha.,.beta.-unsaturated carboxylic acid) may be used in combination with the above, if desired. According to the present invention, the preparation of a gypsum molded product, particularly a gypsum from desulfurization of exhaust gas, is contemplated.