Process for preparing polytrimethylene terephthalate
Patent 6093786 Issued on July 25, 2000. Estimated Expiration Date: 
August 15, 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.
August 15, 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.Patent References 2465319 3386952 3642868 3644482 3676393 3681431 3821169 Thermo-oxidative stable copolyesters Stabilized polyester compositions Stabilized polyester compositions InventorAssigneeApplicationNo. 911848 filed on 08/15/1997US Classes:528/271, FROM CARBOXYLIC ACID OR DERIVATIVE THEREOF528/176, With polycarboxylic acid or derivative as reactant528/193, Two or more phenolic reactants528/194, Two or more polycarboxylic acids or derivatives as reactants528/272, From di- or higher ester of a polycarboxylic acid as sole reactant, or from a polycarboxylic acid or derivative with a compound containing two or more hydroxyl groups or salts thereof528/286, Material contains a phosphorus atom528/287Phosphorus-containing reactantExaminersPrimary: Mosley-Boykin, TerressaForeign Patent References
International ClassC08G 063/02AbstractPolytrimethylene terephthalate is prepared in a process which includes adding a hindered phenol and an aromatic organophosphite to the polymerization reaction mixture. The process generates a reduced level of acrolein and prepares an improved polyester product compared with processes without the phenol and organophosphite additives.Other References
Field of SearchWith polycarboxylic acid or derivative as reactantTwo or more phenolic reactants Two or more polycarboxylic acids or derivatives as reactants FROM CARBOXYLIC ACID OR DERIVATIVE THEREOF From di- or higher ester of a polycarboxylic acid as sole reactant, or from a polycarboxylic acid or derivative with a compound containing two or more hydroxyl groups or salts thereof Material contains a phosphorus atom Phosphorus-containing reactant | |
