Mass polymerization of conjugated dienes with organo lithium catalysts
Abstract
Abstract BUTADIENE AND/OR ISOPRENE, OPTIONALLY WITH STYRENE, ARE MASS POLYMERIZED CONTINUOUSLY BY INTRODUCING AT LEAST PART OF THE MONOMER AND A LITHIUM-BASED INITIATOR INTO THE BOTTOM REGION OF AN ELONGATED, VERTICAL, PRESSURIZED REACTION VESSEL. THE MATERIALS ARE AGITATED, AND PRESSURIZED MONOMER, IF ANY, IS INTRODUCED INTO THE REACTION VESSEL AS THE MATERIALS FLOW FROM THE BOTTOM TO THE TOP OF THE REACTION VESSEL, THROUGH A THROTTLE VALVE, AND THEN INTO A SECOND VESEL, AT LEAST A MAJOR PORTION OF THE HEAT OF RECTION IS CONTAINED WITHIN THE REACTION VESSEL. A PORTION OF UNREACTED MONOMER VAPOR IS REMOVED FROM THE SECOND VESSEL TO CONTROL THE PRESSURE AND TEMPERATURE WITHIN IT; IN THIS MANNER THE PRESSURE, AND HENCE THE TEMPERATURE IN THE REACTION VESSEL ARE CONTROLLED TO PERMIT SOME BOILING IN THE TOP OF THE REACTION VESSEL. THE BOILING PRODUCES AGITATION, AND THE REMOVAL OF VAPOR RAISES THE SOLIDS CONTENT OF THE MATERIALS. THE THROTTLE VALVE CAN BE PARTIALLY CLOSED TO INCREASE THE PRESSURE IN THE REACTION VESSEL MONOMER VAPORS REMOVED ARE CONDENSED AND RECYCLED, AND THE REMAINING MATERIAL IS DISCHARGE FROM THE SECOND VESSEL.
Inventors
- 👤 C Johnson
Bibliographic Details
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