Patent 6288202 Issued on September 11, 2001. Estimated Expiration Date: April 11, 2017. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
528/196, With reactant having halo-C(=O)-halo, halo-C(=O)-O-, or -O-C(=O)-O- group528/198Polymerizing in the presence of a specified material other than a reactant and other than Group IA or Group IIA material as sole metal atom
A process of forming a polycarbonate comprises providing a reaction mixture of at least one polycarbonate-forming monomer and carbon dioxide; and then reacting the polycarbonate-forming monomer and carbon dioxide in the reaction mixture to form the polycarbonate. In one embodiment, the polycarbonate is present in a condensate, and the process further comprises removing carbon dioxide from the reaction mixture; and then collecting the condensate from the reaction mixture. Moreover, uncrystallized polycarbonate may be treated with carbon dioxide to form crystalline polycarbonate. The crystalline polycarbonate is then rendered useful for solid state polymerization.
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