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
Gaming machine cabinet construction and method
Lighting fixture
Communication system
Method for the support of a rotating workpiece during grinding and a hydrodynamic steady rest
Pizza slice container
Thermal detector, thermal detection device, and electronic instrument
Information processing apparatus, method, and computer-readable medium
  Randomly Featured Patents
Exercise apparatus
Upper panel of a drink cup lid
Wireless keyboad with consumer function keys
Method for improved internal exhaust gas recirculation in an internal combustion engine
Paper cassette for an electrophotographic apparatus
Towel dispenser with metering mechanism
Water pump lubricating chamber arrangement for motor vehicles
Machining vise
Cyclopropanecarboxylate insecticides and/or acaricides exhibiting low toxicity to mammals and fish