abstract |
Polyetherimides are formed by the dry blending of organodianhydride, organic diamine, and chain stopper and the polymerization of the dry-blended mixture in a continuous, steady state reaction, employing an extruder reactor as the reaction chamber. The extruder reactor is provided with means for heating and cooling, evacuation of water of reaction, and material conveyance means in order to achieve a steady state necessary for continuous production of a uniform polymeric product. |