Hydraulic fluids containing baron-silicon compounds

A hydraulic fluid composition consisting essentially of at least about 5% by weight based on the weight of the composition of a compound of the general formula:

• ##STR21## wherein each R.sup.7 independently is a hydrocarbyl group, or a group of the formula:
• --(OR.sup.5).sub.n --OR.sup.6 ps
• n is 0 or an integer from 1 to 5, m is 1, 2, or 3, R.sup.5 is an alkylene or an arylene group and each R.sup.5 may be the same as, or different from, any other group R.sup.5, and R.sup.6 is a hydrocarbyl group or hydrogen and each group R.sup.6 may be the same as, or different from, any other group R.sup.6 ;
• together with one or more conventional hydraulic fluid components selected from the group consisting of hydrocarbon oils, silicone oils, natural and synthetic esters, glycols, glycol ethers, phosphorus esters, acetals and silane derivatives.

A hydraulic fluid composition consisting essentially of at least about 5% by weight based on the weight of the composition of a compound of the general formula:

• ##STR22## wherein each R.sup.1 independently is a hydrocarbyl group or a group of the formula:
• --(OR.sup.5).sub.n --OR.sup.6 (i)
• or
• --R.sup.5 --(OR.sup.5).sub.n --OR.sup.6 (ii),
• each R.sup.2 independently is an aryl group or a group of the formula:
• --(OR.sup.5).sub.n --R.sup.6 (i)
• --R.sup.5 --(OR.sup.5).sub.n --R.sup.6 (ii)
• or
• --O(R.sup.5 O).sub.n Si(R.sup.12).sub.3 (iv)
• wherein each R.sup.12 independently is a hydrocarbyl group or a group of the formula (i) or (ii) as defined above, R.sup.8 is a group of the formula:
• --(R.sup.5 O).sub.n --R.sup.6
• and each group R.sup.8 may be the same as, or different from any other group R.sup.8, p is 0, 1 or 2, and R.sup.5 is an alkylene or an arylene group and each R.sup.5 may be the same as, or diferent from, any other group R.sup.5, R.sup.6 is a hydrocarbyl group or hydrogen and each group R.sup.6 may be the same as, or different from, any other group R.sup.6 and n is 0 or an integer from 1 to 5;
• together with one or more conventional hydraulic fluid components selected from the group consisting of hydrocarbon oils, silicone oils, natural and synthetic esters, glycols, glycol ethers, phosphorus esters, acetals and silane derivatives.