Cross-linkable materials based on organosilicon compounds
AssigneeWacker Chemie AG
InventorWolfgang Ziche
Life of this patent
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Abstract
Crosslinkable compositions employing organosilicon compounds having at least two hydrolyzable groups, optionally a crosslinker, and optionally a compound containing basic nitrogen, include a crosslinking catalyst which is a reaction product of a phosphorus compound, a sulfur compound, and a tin compound. The compositions exhibit improved shelf life.
Claims6
A crosslinkable material based on organosilicon compounds having at least two hydrolyzable groups, wherein at least one organotin compound (C) is contained as a catalyst, said organotin compound (C) comprising the reaction product of phosphorus compounds (i) having C—P(═O) (OH) units and sulfur compounds (ii) having —SO3H groups and tin compounds (iii) containing units of the formula
- Ra(XR′)bSnX(4-a-b)/2 (III)
- in which
- R are identical or different and are monovalent, optionally substituted hydrocarbon radicals optionally interrupted by oxygen atoms,
- X are identical or different and are —O— or —S—,
- R′ are identical or different and are a hydrogen atom or a monovalent, optionally substituted hydrocarbon radical optionally interrupted by oxygen atoms or by optionally substituted silyl radicals,
- a is 0, 1, 2, or 3 and
- b is 0, 1, 2, or 3,
- with the proviso that the sum a+b is less than or equal to 4,
- said crosslinkable material further comprising at least one amino-funtional organosilicon compound (D).
A crosslinkable material, comprising:
- (A) at least one diorganopolysiloxane of the formula (V),
- (R5O)3-dR6dSiO—[R62SiO]e—SiR6d(OR5)3-d (V)
- in which
- d is 0, 1, or 2,
- R6 are identical or different SiC-bonded hydrocarbon radicals having 1 to 18 carbon atoms, optionally substituted by halogen atoms, ether groups, ester groups, epoxy groups, mercapto groups, cyano groups, amino groups or (poly)glycol radicals, said (poly)glycol radicals being comprised of oxyethylene and/or oxypropylene units,
- R5 are identical or different and are a hydrogen or a monovalent, optionally substituted hydrocarbon radical optionally interrupted by oxygen atoms or by optionally substituted silyl radicals,
- e is an integer from 10 to 10,000, with the proviso that when d is 2, R5 is a hydrogen atom,
- (B) optionally, crosslinking agents of the formula (VI) and/or the partial hydrolysis products thereof,
- (R7O)4-fSiR8f (VI)
- in which
- R7 are identical or different and have one of the meanings mentioned above for R′,
- R8 has the meaning mentioned above for R,
- f is 0 or 1,
- and the partial hydrolysis products thereof,
- (C) at least one organotin catalyst comprising the reaction product of phosphorus compounds (i) having C—P(═O) (OH) units and sulfur compounds (ii) having —SO3H groups and tin compounds (iii) containing units of the formula
- (Ra(XR′)b SnX(4-a-b)/2 (III)
- in which
- R are identical or different and are monovalent, optionally substituted hydrocarbon radicals optionally interrupted by oxygen atoms,
- X are identical or different and are —O—or —S—,
- R′ are identical or different and are a hydrogen atom or a monovalent, optionally substituted hydrocarbon radical optionally interrupted by oxygen atoms or by optionally substituted silyl radicals,
- a is 0, 1, 2, or 3 and
- b is 0, 1, 2, or 3,
- with the proviso that the sum a+b is less than or equal to 4, and
- (D) a compound of the formula (IV) having basic nitrogen
- (R9O)4-gSiR10g (IV)
- in which
- R9 are identical or different and have one of the meanings mentioned above for R′,
- R10 are identical or different and are monovalent, optionally substituted hydrocarbon radicals containing basic nitrogen,
- g is 1, 2, 3, or 4,
- and the partial hydrolysis products thereof.
Dependencies are inferred from the claim text.