Depolymerization of condensation polymers involving a pre-molecular weight reduction step
Patent 4620032 Issued on October 28, 1986. Estimated Expiration Date: 
December 11, 2004. 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.
December 11, 2004. 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 References3488298 InventorAssigneeApplicationNo. 06/680443 filed on 12/11/1984US Classes:562/483, Preparation by hydrolysis of amide, anhydride, or ester562/458, Carboxyl, or salt thereof, bonded directly to a ring562/485, Purification or recovery per se562/487, By reaction of undesired component562/554, Purification or recovery per se562/590, Polycarboxylic562/593, Purification or recovery per se564/498, Of an alkylene polyamine568/858Preparing by alcoholysis, hydrolysis or saponification of an esterExaminersPrimary: Trousof, NatalieAssistant: Clarke, Vera C. Attorney, Agent or FirmInternational ClassC07C 51/09 (20060101)AbstractThere is disclosed a process for reducing the reaction time in the hydrolysis of a condensation polymer wherein molten condensation polymer is intimately admixed with a depolymerizing agent which is either (i) one of the products resulting from the complete hydrolytic depolymerization of the condensation polymer; or (ii) water. The depolymerization agent is present in the mixture in an amount which is less than the weight of the condensation polymer and the materials are intimately admixed for a time sufficient that the molecular of the condensation polymer is reduced by at least 50%. The treated condensation polymer of lower molecular weight is thereafter subjected to neutral hydrolysis. In addition to decreasing the overall time required to effect complete hydrolytic depolymerization, this process additionally permits the use of a smaller hydrolysis vessel, thereby reducing the fabrication cost of the hydrolysis unit. |
| ||||||||||||||
