摘要 |
NEW MATERIAL:A compound of formula I (R is 5-30C aliphatic or alicyclic hydrocarbon group: (n) is 2, 3). EXAMPLE:Dipropylene glycol-di(2-ethylhexyl) carbonate. USE:A lubricant, freezer oil and electric insulating oil. The compound of formula I has excellent compatibility with ozone layer-non-decomposable Freon (e.g. R134a) and is especially suitable for freezers employing the fleon as a cooling medium. PREPARATION:While a produced alcohol (R1OH) is removed outside the reaction system, dipropylene glycol or tripropylene glycol is made to react with a carbonate compound of formula II (R1 is R) in a ratio of m1/2m2 (m1 is the mole number of the carbonate compound; m2 is the mole number of the propylene glycol compound) or 2-50, preferably 2-30, to provide the compound of formula I. |