Process of preparing polymers of nuclearly polychlorinated aromatic dicarboxylic acids and diamines having at least 4 carbons

Claim 1

A PROCESS FOR PREPARING A POLYAMIDE FROM AN ARYL DIESTER OF A NUCLEARLY POLYCHLORINATED AROMATIC DICARBOXYLIC ACID AND AN EQUIMOLECULAR PROPORTION OF AN ORGANIC BIFUNCTIONAL ALIPHATIC DIAMINE CONTAINING AT LEAST 4 CARBON ATOMS, SAID ARYL DIESTER BEING COMPOSED OF AN AROMATIC HYDROCARBON GROUP HAVING TWO NUCLEARLY ATTACHED CARBARYLOXY RADICALS AND FROM TWO TO FOUR NUCLEARLY ATTACHED CHLORINE ATOMS, SAID PROCESS COMPRISING THE STEPS OF (A) HEATING SAID ARYL DIESTER AND SAID ALIPHATIC DIAMINE UNDER A VACUUM AT FROM 200*-350*C. UNTIL A PREPOLYMER IS OBTAINED HAVIG A DEGREE OF POLYMERIZATION CORRESPONDING TO AN INHERENT VISCOSITY OF FROM ABOUT 0.1 TO ABOUT 0.5, (B) PULVERIZING SAID PREPOLYMER TO FORM A POWDER, (C) HEATING SAID PREPOLYMER POWDER AT BELOW ITS MELTING POINT AND ABOVE 175*C. UNTIL A POWDER OF SAID POLYAMIDE IS OBTAINED HAVING AN INHERENT VISCOSITY IN THE RANGE OF 0.5-3.0.