Solid phase process for linear superpolyesters

Claim 1

A PROCESS FOR PREPARING A LINEAR SUPERPOLYESTER OF AT LEAST ONE CLYCOL AND AT LEAST ONE DIBASIC ACID COMPRISING AT LEAST 50 MOLE PERCENT OF AN ACID HAVING TWO CARBOXYL RADICALS ATTACHED TO A HEXACARBOCYCLIC NUCLEUS, SAID SUPERPOLYESTER HAVING AN INHERENT VISCOSITY IN A MIXTURE OF 60% PHENOL AND 40% TETRACHLOROETHANE OF AT LEAST 0.5 AND MELTING AT FROM ABOUT 180* TO ABOUT 350*C., COMPRISING HEATING IN AN ENCLOSED POLYMERIZATION ZONE WHEREIN AT LEAST 5% OF THE VOLUME IS OCCUPIED BY PARTICLES OF A SOLID PREPOLYMER OF SAID SUPERPOLYESTER HAVING AN INHERENT VISCOSITY OF FROM ABOUT 0.1 TO ABOUT 0.45, WHICH PARTICLES SUBSTANTIALLY COMPLETELY PASS A 20 MESH SCREEN WITH LESS THAN 25% PASSING A 200 MESH SCREEN, WHICH PREPOLYMER CONTAINS AN ORGANOTITANIUM CATALYST, SAID HEATING BEING AT FROM 5* TO 80*C. BELOW THE MELTING POINT OF SAID PREPOLYMER AND BETWEEN 175* AND 300*C. IN THE PRESENCE OF A DRY GAS SELECTED FROM THE GROUP CONSISTING OF NITROGEN, CARBON DIOXIDE, HELIUM, PROPANE, DRIED AIR, DRIED BURNT NATURAL GAS AND MIXTURES THEREOF WHICH CONTAIN NO MORE THAN ABOUT 0.1% BY WEIGHT OF CARBON MONOXIDE AT ABOUT ATMOSPHERIC PRESSURE WHICH FLOWS THROUGH SAID ZONE AT FROM ABOUT 10 TO ABOUT 1,000 ML. OF DRY GAS PER MINUTE PER GRAM OF SAID PARTICLES, ANY OF SAID PARTICLES MORE THAN 5 MM. FROM THE SURFACE BEING AGITATED INTO CONTACT WITH SAID DRY GAS, WHEREBY A SUPERPOLYESTER HAVING AN INHERENT VISCOSITY OF AT LEAST 0.5 AND ALSO AT LEAST 0.3 UNIT GREATER THAN FOR SAID PREPOLYMER IS OBTAINED WITHIN ONE HOUR OF COMMENCING SAID HEATING IN SAID POLYMERIZATION ZONE.