Aliphatic oligocarbonate polyols prepared in the presence of a catalyst and a process for preparing the same

1. An aliphatic oligocarbonate polyol which has a molecular weight of from 500 to 5000 which comprises the reaction product of:

A) at least one organic carbonate selected from diphenyl carbonate, dimothyl carbonate, diethyl carbonate and ethylene carbonate; and

B) at least one aliphatic polyol selected from linear, cyclic, branched, unbranched, saturated or unsaturated polyols having from 2 to 25 carbon atoms and primary, secondary or tertiary hydroxyl functionality of greater than or equal to 2;

wherein A) and B) have been reacted in the presence of

C) at least one catalyst comprising

i) at least one rare earth metal, complex, organic or inorganic compound or salt thereof or mixtures thereof; or

ii) at least one metal of group III B of the periodic table of the elements, complex, organic or inorganic compound or salt thereof or mixtures thereof; or

iii) mixtures of i) and ii);

provided that the rare earth metal or metal of group III B of the periodic table of the elements is not cerium, a cerium compound or lanthanum hydroxide.

2. The aliphatic oligocarbonate polyol of claim 1 wherein the organic carbonate is dimethyl carbonate, diethyl carbonate or diphenyl carbonate.

3. The aliphatic oligocarbonate polyol of claim 1 wherein the aliphatic polyol is a diol, an aliphatic diol, a triol, a ring-opening adduct of an aliphatic diol and a lactone or a ring-opening adduct of an aliphatic diol and ε-caprolactone or mixtures thereof.

4. The aliphatic oligocarbonate polyol of claim 1 wherein the aliphatic polyol is 1,6-hexanediol, a ring-opening adduct of 1,6-hexanediol and ε-caprolactone or mixtures thereof.