Compositions containing (A) at least one silane-terminated polyether derivative with a content of polyether groups from 10 to 98% and a content of 1 to 25% terminal groups with the structure —NR1—X—Si(OR2)mR3(3-m)  (I) in which m denotes 1, 2 or 3 R1, R2, R3 independently of each other denote H or a saturated or unsaturated, linear, branched, cyclic or polycyclic hydrocarbon group with 0 to 10 heteroatoms from the group O, N, S and a total of 1 to 30 carbon atoms, X denotes a group with the empirical formula CnH2n, n denotes a whole number ≧3, with the stipulation that n>3, if R1 stands for H, (B1) water and (B2) at least one organic or inorganic acid, as well as optional diluents and/or fillers and/or ordinary additives, are suitable for preparation of molding compounds, especially in the dental field.