| 摘要 |
Described is a process for exchanging some or all of the radicals R' in alkoxysilane cluster compounds with different radicals R''; this process being based on the following reaction: <IMAGE> +TR RSi[SiO4]3[R' ]9-n[R'']n + nR'OH wherein R is hydrogen, an alkyl, an alkenyl, and an aryl, or an aralkyl; and each R' is independently selected from the same groups as R with the proviso that at least a majority of said R' radicals are sterically hindered alkyl groups having at least 3 carbon atoms; and each R'' is selected from groups consisting of alkyl groups, alkenyl groups, aryl groups, aralkyl groups, functionally substituted alkyl, alkenyl, aryl and aralkyl groups, and polyoxyalkylene groups with the proviso that R'' radicals are different than R' radicals; and n is a number from 1 to 9. Also described are novel alkoxysilane cluster compounds made by this process; these compounds being represented by the following chemical formula: <IMAGE> wherein R, R' and R'' are as defined above, and x, y, and z are individually selected from 0, 1, 2, or 3 with the proviso that the sum of x+y+z is from 1 to 8. Also, described are functional fluid systems (i.e., hydraulic fluid and heat transfer fluid systems) containing these novel alkoxysilane cluster compounds of the above formula. |
