Polycarbonates, uses thereof, processes for preparing and purifying same

A lubricating oil containing a polycarbonate represented by the following general formula [II]:

• (R.sub.1 O)CH.sub.2 [CH(OR.sub.1)].sub.m CH.sub.2 (OR.sub.1) [II]
• wherein R.sub.1 is a group represented by the following formula (E) or (F), and m is an integer of 1 to 6;
• --(C.sub.3 H.sub.6 O).sub.n COOR.sub.2 (E)
• wherein each R.sub.2 is independently a hydrocarbon group having not more than 30 carbon atoms or a hydrocarbon group containing an ether bond and having 2 to 30 carbon atoms, and n is an integer of 1 to 12,
• --(C.sub.3 H.sub.6 O).sub.n (C.sub.2 H.sub.4 O).sub.p COOR.sub.2 (F)
• wherein each R.sub.2 is independently a hydrocarbon group having not more than 30 carbon atoms or a hydrocarbon group containing an ether bond and having 2 to 30 carbon atoms, n and p are an integer of 1 to 12.

A lubricating oil for refrigerator containing:

• (i) a polycarbonate represented by the formula (II)
• (R.sub.1 O)CH.sub.2 (CH(OR.sub.1)).sub.m CH.sub.2 (OR.sub.1) (II)
• wherein R.sub.1 is a group represented by the following formulae (E) or (F), and m is an integer of 1 to 6,
• --(C.sub.3 H.sub.6 O).sub.n COOR.sub.2 (E)
• wherein each R.sub.2 is independently a hydrocarbon group having not more than 30 carbon atoms or a hydrocarbon group containing an ether bond and having 2 to 30 carbon atoms, and n is an integer of 1 to 12,
• --(C.sub.3 H.sub.6 O).sub.n (C.sub.2 H.sub.4 O).sub.p COOR.sub.2 (F)
• wherein each R.sub.2 is independently a hydrocarbon group having not more than 30 carbon atoms or a hydrocarbon group containing an ether bond and having 2 to 30 carbon atoms, n and p are an integer of 1 to 12;
• and
• (ii) (a) an ozone layer non-destructive hydrogenated fluorocarbon, or
• (b) a small ozone depletion potential hydrogenated chlorofluorocarbon, or
• (c) a mixture of (a) and (b).

A lubricating oil for refrigerator containing:

• (i) a polycarbonate represented by the formula (II)
• (R.sub.1 O)CH.sub.2 (CH(OR.sub.1)).sub.m CH.sub.2 (OR.sub.1) (II)
• wherein R.sub.1 is a group represented by the following formulae (E) or (F), and m is an integer of 1 to 6,
• --(C.sub.3 H.sub.6 O).sub.n COOR.sub.2 (E)
• wherein each R.sub.2 is independently a hydrocarbon group having not more than 30 carbon atoms or a hydrocarbon group containing an ether bond and having 2 to 30 carbon atoms, and n is an integer of 1 to 12,
• --(C.sub.3 H.sub.6 O).sub.n (C.sub.2 H.sub.4 O).sub.p COOR.sub.2 (F)
• wherein each R.sub.2 is independently a hydrocarbon group having not more than 30 carbon atoms or a hydrocarbon group containing an ether bond and having 2 to 30 carbon atoms, n and p are an integer of 1 to 12;
• and
• (ii) an ozone layer non-destructive refrigerant.