Agglomeration of plastic particles in liquid suspension
Abstract
Abstract A PROCESS FOR PREPARING LARGE PARTICLES OF PLASTIC MATERIALS, PARTICULARLY POLYVINYL CHLORIDE. A SUBSTANTIALLY WATER IMMISCIBLE SOLVENT FOR THE PLASTIC MATERIAL IS FIRST DISPERSED IN AN AQUEOUS MEDIUM. THE AQUEOUS MEDIUM IS HEATED TO A TEMPERATURE IN THE RANGE OF FROM ABOUT 45*C. TO ABOUT 85*C. THE WATER-SOLVENT MIXTURE IS STIRRED TO DISPERSE THE SOLVENT INTO FINE DROPLETS. SMALL PARTICLE SIZE PLASTIC MATERIAL IS THEN ADDED TO THE WATER-SOLVENT MIXTURE WHILE CONTINUING THE STIRRING. STIRRING IS CONTINUED UNTIL AGGLOMERATES OF THE DESIRED SIZE ARE FORMED. SOLVENT IS REMOVED BY DISTILLATION AND THE LARGE PARTICLE SIZE PLASTIC MATERIAL IS RECOVERED BY CENTRIFUGING OR FILTERING. PAR TICLES PRODUCED BY THIS PROCESS ARE SUITABLE FOR USE AS A FILTER MEDIA.
Inventors
- 👤 William E Burt
- 👤 Michael E Kucsma
Bibliographic Details
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