Hydrolytically stable hydraulic fluids - based on amino:silane(s) which are soluble in glycol- and silicone-based hydraulic fluids

摘要

A hydraulic fluid contains 1 or more aminosilane of formula R(4-n)Si(NR1R2)n (I) (where R is 1-12C alkyl or alkoxy, 2-12C alkenyl, aryl, arylalkyl, 3-10C cycloalkyl, or a gp. R'(OCHR3CHR4)x or H(OCHR3CHR4)x; where R' is 1-4C alkyl, R3 and R4 are H or 1-3C alkyl and x is 1-5; R1 is H or R, omitting the alkenyl gp., R2 is R, omitting the alkenyl gp; n is 1-3). A pref. compsn. for the hydraulic fluid has 30-70 wt.% (I), 30-70 wt.% of 1 or more oxyalkyleneglycolmono- or dialkyl ethers, and 0-40 wt.% of a mixt. of 1 or more boric esters with an appropriate glycol or deriv. The aminosilanes are sol. in glycol-based as well as in silicone-based hydraulic fluids. Their hydrolytic stability is much higher than that of e.g. silicate esters currently used, and pptn. of hydrolysis prods. can be further suppressed by addns. of inhibitors and/or solvents.