Gypsum mixture containing silane or polysiloxane and metal salt, useful for preparing shaped articles and plaster board with good water resistance and flexural strength

摘要

Gypsum mixture (A) contains at least one additive consisting essentially of (i) at least one silane (I) and/or polysiloxane (II) and (ii) at least one salt (III) of an inorganic acid and metal of subgroups IIIA-VIIIA, IB or IIB, optionally also other additives or auxiliaries. Gypsum mixture (A) contains at least one additive consisting essentially of (i) at least one silane (I) and/or polysiloxane (II) and (ii) at least one salt (III) of an inorganic acid and metal of subgroups IIIA-VIIIA, IB or IIB, optionally also other additives or auxiliaries. (I) has formula R xSi(OR') y and (II) contains at least two groups of formula SiR m(OR') n. each R : optionally substituted organic group; x : 0-3; each R' : 1-4C alkyl; y : 1-4, with x + y = 4; m : 0-2; n : 1-3, with m + n = 3 or lower . Independent claims are included for: (1) method for preparing (A) by homogeneous dispersion of (I) and (II) into gypsum; and (2) shaped articles and plaster boards prepared at least partly from (A).