| 摘要 |
Prodn. of siloxane ester comprises reaction of polysiloxane of formula (R3SiO)z-(SiR1R2O)w-(SiR3)z (where z is 0 or 1; w is 4-50, R, R1 are 1-4C alkyl; R2 is R3-(OR4)m-R5; R3 is 2-4C hydrocarbon gp.; R4 is 2-3C hydrocarbon gp.; R5 is 1-4C alkyl; and m is 1-10) with a glycol ether of formula R6-(OCxH2x)-OH- where R6 is 1-4C alkyl; x is 2 or 3; and y is 1-5. Pref. molar ratio of glycol ether to silicon is 2-50 and the reaction is carried out at 130-200 deg.C. Glycol ether is pref. di- or tri-ethyleneglycol methyl ether and R2 contains at least 8 carbon and 3 oxygen atoms. Reaction prod. can be transesterified with a glycol (pref. di- or tri-ethyleneglycol). USE/ADVANTAGE - Cpds. are usable as hydraulic fluids (claimed use) and show advantageous stability, toxicological, water absorptive and low temp. flow properties.
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