The present invention provides carboxy-terminated oligomeric polyester compositions useful in the preparation of “weatherable” polymeric materials, for example weatherable copolyestercarbonates. In one aspect the present invention provides an oligomeric polyester composition comprising structural units derived from at least one diacid, at least one diaryl carbonate and at least one diol. The structural units derived from the diacid are present in a molar excess of from about 10% to about 40% based on a ratio of moles of diacid-derived structural units to moles of diol-derived structural units present in the oligomeric polyester composition. The oligomeric polyester composition is further characterized by the presence of atleast some phenoxy end groups.
                            本发明提供了用于制备 "耐候性 "聚合物材料(例如耐候性共聚酯
碳酸酯)的羧基封端低聚聚酯组合物。一方面,本发明提供了一种低聚聚酯组合物,该组合物包含由至少一种二元酸、至少一种二芳基
碳酸酯和至少一种二元醇衍生的结构单元。根据低聚聚酯组合物中存在的二元酸衍生结构单元摩尔数与二元醇衍生结构单元摩尔数之比,二元酸衍生结构单元的摩尔过量约为 10%至 40%。低聚聚酯组合物的进一步特征是至少存在一些苯氧基端基。