Syndiotactic crystalline copolymers of propylene and 1-butene
Patent 5196496 Issued on March 23, 1993. Estimated Expiration Date: 
June 26, 2011. 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.
June 26, 2011. 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 ReferencesProcess and catalyst for producing syndiotactic polyolefins Patent #: 4892851 InventorsAssigneeApplicationNo. 721049 filed on 06/26/1991US Classes:526/348.6, At least four carbon atoms526/160, Transition metal bonded to carbon atom526/901MONOMER POLYMERIZED IN VAPOR STATE IN PRESENCE OF TRANSITION METAL CONTAINING CATALYSTExaminersPrimary: Teskin, FredForeign Patent References
International ClassesC08F 210/06C08F 004/64 Foreign Application Priority Data1990-06-27 ITAbstractEssentially syndiotactic crystalline copolymers of propylene with minor proportions of 1-butene, endowed with good mechanical properties, lowered melting point and limited solubility in xylene at 25° C. and the process for their preparation by polymerizing mixtures of propylene with 1-butene, by using catalysts obtained form stereorigid and chiral zirconium and hafnium compounds and from polymethylalumoxane compounds. | |
