| 摘要 |
Methoxyfunctional organopolysiloxanes having a narrow mol. wt. distribution and an average mol. wt. of no greater than 2000 g/mol contain at least 80% of polysiloxane having a mol. wt. of 800-2000 g/mol. A methoxyfunctional organopolysiloxane (I) having a narrow mol. wt. distribution and an average mol. wt. of no greater than 2000 g/mol is of formula (1) whereby at least 80% of the polysiloxane (I) has a mol. wt. of 800-2000 g/mol. An Independent claim is included for a process for the production of the organopolysiloxane of formula (I) by reaction of a silane of formula (2) or optionally (3), (4) or (5)-(7) and/or their corresponding hydrolysates whereby in a first step the organotrichlorosilane of formula (2) of greatest reactivity is reacted with methanol or methanol/water such that 1-2 equivalents of the hydrolyzable group X is reacted and in a second step the reaction mixture containing the silanes of lower reactivity are reacted with further methanol/water to form the end product. R<2>SiX3 (2) R<2>2SiX2 (3) R<3>O(R<2>2SiO-)nR<3> (5) (R<2>)3SiX (6) (R<2>)3Si-O-Si(R<2>)3 (7) R<1> = methyl; R<2>, R<3> = phenyl or 1-4C alkyl; a = 1-1.7; b = ≤ 1; X = hydrolysable group such as Cl or 1-6C alkoxy; and n = 1-500.
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