| abstract |
(57) [Problem] To provide a high molecular weight unsaturated polyester having excellent strength, which cannot be achieved by the prior art. An aliphatic polyhydric alcohol or a mixture thereof and an aliphatic polybasic acid or a mixture thereof, or an oligomer thereof, or a polymer are heated and dehydrated at a relatively low temperature in an organic solvent in the presence of a catalyst. Thus, a method for producing a high-molecular-weight unsaturated polyester without problems such as gelation was found. [Effect] A high molecular weight unsaturated polyester can be provided by heating and dehydrating an aliphatic polyhydric alcohol and an aliphatic polybase in an organic solvent. |