Process for preparing alpha-olefin polymers which are substantially free of residual catalyst

Claim 1

A PROCESS FOR PREPARING A SOLID ALPHA-OLEFIN POLYMER WHICH IS SUBSTANTIALLY FREE OF HARMFUL RESIDUAL CATALYST WHICH COMPRISES: (A) POLYMERIZING IN AN ENCLOSED ZONE IN A LIQUID HYDROCARBON MEDIUM A GASEOUS ALPHA-OLEFIN OF THE FORMULA R-CH=CH2 WHEREIN R IS A MEMBER OF THE GROUP CONSISTING OF HYDROGEN AND AN ALKYL GROUP HAVING FROM 1 TO 12 CARBON ATOMS AT AN ALPHA-OLEFIN PARTIAL PRESSURE OF ABOUT 10 TO 135 P.S.I.G. AND AT A TEMPERATURE OF FROM 38 TO 90*C. WITH STIRRING AND EFFICIENT COOLING FOR A PERIOD OF ABOUT 5 TO 20 MINUTES IN THE PRESENCE OF A FOUR COMPONENT CATALYST CONSISTING ESSENTIALLY OF THE REACTION PRODUCT OF (1) A HALIDE OF A METAL SELECTED FROM THE GROUP CONSISTING OF GROUP IV(B), GROUP VB AND GROUP VI(B) METALS, (2) AN ORGANOALUMINUM MONOHALIDE, (3) AN ORGANOALUMINIUM HYDROCARBON, AND (4) AN ORGANIC PHOSPHINE, THE ORGANIC RADICALS OF THE FOREGOING CATALYST COMPONENTS HAVING FROM ONE TO TWELVE CARBON ATOMS, TO FORM A CRUMBLY, DARK SOLID MIXTURE OF POLYPROPYLENE AND CATALYST, AND (B) UNDER SUBSTANTIALLY STATIC CONDITIONS POLYMERIZING UNDER AUTOGENOUS PRESSURE LIQUID ALPHA-OLEFIN OF THE FORMULA R-CH=CH2 WHERE R IS A MEMBER OF THE GROUP CONSISTING OF HYDROGEN AND AN AKYL GROUP HAVING FROM 1 TO 12 CARBON ATOMS ONTO THE DARK COLORED SOLID CATALYST-POLY ALPHA-OLEFIN MIXTURE AT FROM ABOUT 50 TO 90*C. FOR A PERIOD RANGING FROM 1 TO 24 HOURS TO FORM ULTIMATELY A TWO-PHASE SOLID MASS THE MINOR PHASE OF WHICH IS THE CRUMBLY, DARK COLORED SOLID POLY ALPHA-OLEFINCATALYST MIXTURE AND THE MAJOR PHASE OF WHICH IS A HARD, LIGHT COLORED POLYMER LOW IN RESIDUAL CATALYST CONTAMINATION, AND (C) MECHANICALLY SEPARATING THE LIGHT COLORED HARD POLYMER WHICH IS LOW IN RESIDUAL CATALYST CONTAMINATION FROM THE DARK COLORED CATALYST-POLYMER MIXTURE AND DRYING SAID HARD POLYMER.