Catalytic process for the thermal degradation of polyolefins

• US 3,345,352 A
• Filed: 02/21/1964
• Issued: 10/03/1967
• Est. Priority Date: 02/21/1964
• Status: Expired due to Term

• Current Assignee: Joseph J. Baron Jr, Julius P. Rakus
• Original Assignee: Joseph J. Baron Jr, Julius P. Rakus
• Inventors: Baron, Joseph J. Jr., Rakus, Julius P.
• Application Number:
  US04/346,403
• Time in Patent Office: 1,320 Days
• US Class Current: 525/362
• CPC Class Codes: C08F 110/02 Ethene
• CPC Class Codes: C08F 110/06 Propene
• CPC Class Codes: C08F 110/08 Butenes
• CPC Class Codes: C08F 8/50 Partial depolymerisation
• CPC Class Codes: Y10S 260/43 Promoting degradability of polymers
• CPC Class Codes: Y10S 526/914 Polymer degradation

Claims

1. THE POLYOLEFIN THERMAL DEGRADATION PROCESS WHICH COMPRISES MIXING A CRYSTALLINE POLYOLEFIN WITH 0.075% TO 10% BY WEIGHT OF A DEGRADATION CATALYST FROM THE GROUP CONSISTING OF (1) OXIDES AND (2) CARBONATES OF (A) ALKALI METALS, (B) ALKALINE EARTH METALS, AND (C) HEAVY METALS FROM THE GROUP CONSISTING OF ANTIMONY, BISMUTH, CADMINUM, CHROMIUM, COPPER, IRON, LEAD, MERCURY, TANTALUM, TITANIUM, THALLIUM, VANADIUM AND ZINC, AND MIXTURES THEREOF;

HEATING THE RESULTING MIXTURE IN AN ATMOSPHERE SUBSTANTIALLY FREE OF OXYGEN TO A TEMPERATURE OF FROM 275* TO 450*C. FOR A MINIMUM TIME PERIOD OF AT LEAST 5 MINUTES WHEN AT THE HIGHEST CATALYST CONCENTRATION, HIGHEST CATALYST DEGRADATION ACTIVITY, AND MOST ACTIVE TEMPERATURE CONDITIONS, SAID MINIMUM TIME INCREASING WITH DECREASING TEMPERATURE, CATALYST CONCENTRATION AND CATALYST DEGRADATION ACTIVITY;

AND RECOVERING A POLYOLEFIN HAVING A MOLECULAR WEIGHT REDUCED BY AT LEAST 45% COMPARED TO THE MOLECULAR WEIGHT OF THE STARTING POLYOLEFIN.