Resources Contact Us Home
Process and catalyst for producing crystalline polyolefins

Image Number 6 for United States Patent #5589556.

Catalyst and process for the stereospecific propagation of a polymer chain derived from an ethylenically unsaturated monomer which contains 3 or more carbon atoms or is substituted vinyl compound. The catalysts comprise stereorigid metallocenes in which a structural bridge is not required for stereorigidity. The ring structures of the metallocene catalyst are substituted cyclopentadienyl rings. The substituent groups on the cyclopentadienyi rings impart stereorigidity to the catalyst by virtue of a sterically hindered relationship between the rings sufficient to prevent rotation of the rings. The catalyst is contacted with a C.sub.3 + alpha olefin or other ethylenically unsaturated compound in a polymerization reaction zone and maintained in contact with the catalyst in the reaction zone under polymerization conditions to produce a stereospecific polymer.

  Recently Added Patents
Method and apparatus for re-routing calls in a packet network during failures
Method and apparatus for organizing segments of media assets and determining relevance of segments to a query
System for setting programmable parameters for an implantable hypertension treatment device
Motor with power-generation coil module
Lacrosse head
Method and apparatus for verifiable generation of public keys
Systems and/or methods for using air/wind power to charge/re-charge vehicle batteries
  Randomly Featured Patents
Heat resistant conveyor belt with side walls
Technique for removing iron-rich components from a copper melt
Novel peptide and salts thereof and peptide antiallergic agents containing these peptides
Brake servo device for motor vehicles
Method to manufacture silicon quantum islands and single-electron devices
Rod cooling apparatus
Grandiflora rose plant named `Meikanaro`
System and method for efficiently inscribing bullion articles utilizing a milling tool and a numeric controller
Method for dehydrogenating C.sub.2-C.sub.30-alkanes
Semiconductor memory device