Cross-linkable compositions based on organyl oxysilane-terminated polymers

A crosslinkable composition (Z), comprising:

• (A) 100 parts by weight of compound(s) of the formula
• Y—[(CR12)a—Si(OR)3]x (I),
• where
• Y is an x-valent polymer radical bonded via nitrogen or oxygen,
• R each is identical or different and is hydrogen or a monovalent, optionally substituted hydrocarbon radical,
• R1 each is identical or different and is hydrogen or a monovalent, optionally substituted hydrocarbon radical which may be attached via nitrogen, phosphorus, oxygen, sulfur or carbonyl group to the carbon atom,
• x is an integer from 2 to 10 and
• a is an integer from 1 to 10,
• with the proviso that in component (A) in 5% to 60% of all the units [(CR12)a—Si(OR)3] a is 1 and in at least 5% of all the compounds of the formula (I) per molecule at least one a is 1 and at least one a is an integer from 2 to 10,
• (B) at least 0.1 part by weight of tetraethoxysilane and/or silanes of the formula
• R4—Si(CH3)b(OR2)3-b (II),
• where
• R2 each is identical or different and is hydrogen or a monovalent, optionally substituted hydrocarbon radical,
• R4 is a monovalent, optionally substituted hydrocarbon radical optionally interrupted by oxygen atoms and which contains no nitrogen atom not bonded directly to a carbonyl group, and no heteroatom separated only by a single carbon atom from the silicon atom,
• and
• b is 0 or 1, and also
• (C) optionally at most 2 parts by weight of one or more silanes of the formula
• X—CH2—SiR6c(OR5)3-c (III),
• where
• R5 each is identical or different and is hydrogen or a monovalent, optionally substituted hydrocarbon radical,
• R6 each is identical or different and is a monovalent, optionally substituted hydrocarbon radical,
• X is a group of the formula —NR72, —NR7—CO—R8, —NR7—CO—OR8, —NR7—CO—NR82, —OR7, —O—CO—R7, O—CO—OR7, O—CO—NR72 or a heterocycle bonded via N atom,
• R7 each is identical or different and is hydrogen or a monovalent, optionally substituted hydrocarbon radical having 1 to 6 carbon atoms,
• R8 each is identical or different and is hydrogen or a monovalent, optionally substituted hydrocarbon radical having 1 to 6 carbon atoms and
• c is 0 or 1.