Profile extension process for thermoplastic resins and ceramic thermoplastic resin binder compositions

Claim 2

IN A PROCESS FOR CONTINUOUSLY EXTRUDING THERMOPLASTICS IN THE FORM OF A PROFILE WITH ONE MORE CHANNELS WHEREIN EACH OF SAID CHANNELS HAS A CROSS SECTIONAL DIAMETER OF ABOUT 0.01 TO 0.25 INCHES, THE IMPROVEMENT COMPRISING INCLUDING A MATERIAL VOLATILE AT THE EXTRUSION TEMPERATURE, SELECTED FROM THE GROUP CONSISTING OF PENTANE, HEXANE, HEPTANE AND LOW BOILING HYDROCARBON OILS TO THE PLASTIC COMPOSITION TO PREVENT COLLAPSE OF THE PROFILE DURING THE EXTRUSIONS AND CARRYING OUT THE EXTRUSION AT A TEMPERATURE OF ABOUT 200* TO 600*F.

Claim 3

In a process for continuously extruding thermoplastics in the form of a profile with one or more channels wherein each of said channels has a cross sectional diameter of 0.01 to 0.25 inches; the improvement comprising including hydrocarbon blowing agents or chemical blowing agents decomposable at the extrusion temperature to the plastic composition to prevent collapse of the profile during the extrusion and carrying out the extrusion at a temperature of 200* to 600*F.

Claim 4

In a process for continuously extruding thermoplastics in the form of a profile with one or more channels wherein each of said channels has a cross sectional diameter of 0.01 to 0.25 inches; the improvement comprising including hydrocarbon blowing agents or chemical blowing agents decomposable at the extrusion temperature to the plastic composition to prevent collapse of the profile during the extrusion and carrying out the extrusion at a temperature of 200* to 600*F.

Claim 5

The process according to claim 2 wherein the blowing agent is azobisformamide.

Claim 6

The process according to claim 1 wherein the plastic is polyethylene containing a filler selected from the group consisting of cordierite, mullite, spinel and alumina.

Claim 7

A PROCESS FOR PREPARING A CERAMIC STRUCTURE IN THE FORM OF A PROFILE WITH ONE OR MORE CAVITIES THAT MAINTAINS ITS INTEGRITY DURING AND AFTER EXTRUSION WHICH COMPRISES: A. PREPARING A MIXTURE MADE UP OF 5 TO 50 VOLUME PERCENT OF A POLYOLEFIN, 20 TO 50 VOLUME PERCENT OF A FILLER SELECTED FROM THE GROUP CONSISTING OF CORDIERITE, MULLITE, SPINEL, AND ALUMINA, 5 TO 60 VOLUME PERCENT OF A MINERAL OIL PLASTICIZER AND 0.05 TO 2.0 VOLUME PERCENT OF A MOLATILE MATERIAL SELECTED FROM THE GROUP CONSISTING OF PENTANE, HEXANE, HEPTANE AND LOW BOILING HYDROCARBON OILS. B. HEATING THE MIXTURE FROM 200* TO 500*F. AND EXTRUDING THE MATERIAL THROUGH A DIE CONTAINING A MANDREL TO FORM A TUBULAR EXTRUDATE HAVING ONE OR MORE CAVITIES THEREIN. C. CUTTING THE EXTRUDATE INTO SECTIONS AND EXTRACTING THE PLASTICIZER, D. HEATING TO 300* TO 700*C TO BURN OFF THE POLYOLEFIN AND, E. SINTERING AT TEMPERATURES OF 1400* TO 1700*C. AND RECOVERING THE PRODUCT.

Claim 8

A PROCESS FOR PREPARING A CERAMIC STRUCTURE IN THE FORM OF A PROFILE WITH ONE OR MORE CAVITIES THAT MAINTAINS ITS INTEGRITY DURING AND AFTER EXTRUSION WHICH COMPRISES: A. PREPARING A MIXTURE MADE UP OF 5 TO 50 VOLUME PERCENT OF A POLYOLEFIN, 20 TO 50 VOLUME PERCENT OF A FILLER SELECTED FROM THE GROUP CONSISTING OF CORDIERITE, MULLITE, SPINEL, AND ALUMINA, 5 TO 60 VOLUME PERCENT OF A MINERAL OIL PLASTICIZER AND 0.05 TO 2.0 VOLUME PERCENT OF A MOLATILE MATERIAL SELECTED FROM THE GROUP CONSISTING OF PENTANE, HEXANE, HEPTANE AND LOW BOILING HYDROCARBON OILS. B. HEATING THE MIXTURE FROM 200* TO 500*F. AND EXTRUDING THE MATERIAL THROUGH A DIE CONTAINING A MANDREL TO FORM A TUBULAR EXTRUDATE HAVING ONE OR MORE CAVITIES THEREIN. C. CUTTING THE EXTRUDATE INTO SECTIONS AND EXTRACTING THE PLASTICIZER, D. HEATING TO 300* TO 700*C TO BURN OFF THE POLYOLEFIN AND, E. SINTERING AT TEMPERATURES OF 1400* TO 1700*C. AND RECOVERING THE PRODUCT.

Claim 9

The process according to claim 5 wherein the polyolefin is polyethylene and the mineral oil plasticizer is extracted by immersing the extrudates in trichloroethane.

Claim 10

A process for preparing a ceramic structure in the form of a profile with one or more cavities that maintains its integrity during and after extrusion which comprises: a. preparing a mixture made up of 10 to 50 volume percent of a polyolefin, 20 to 40 volume percent of a filler selected from the group consisting of cordierite, mullite, spinel, and alumina, 20-60 volume percent of a mineral oil plasticizer and 0.05 to 0.2 volume percent of a blowing agent selected from the group consisting of hydrocarbon blowing agents and azobisformamide, b. heating the mixture from 200* to 500*F. and extruding the material through a die containing a mandrel to form a tubular extrudate having one or more cavities therein, c. cutting the extrudate into sections and extracting the plasticizer, d. heating to 300* to 700*C. to burn off the polyolefin and, e. sintering at a temperature of 1400* to 1700*C and recovering the product.

Claim 11

A process for preparing a ceramic structure in the form of a profile with one or more cavities that maintains its integrity during and after extrusion which comprises: a. preparing a mixture made up of 10 to 50 volume percent of a polyolefin, 20 to 40 volume percent of a filler selected from the group consisting of cordierite, mullite, spinel, and alumina, 20-60 volume percent of a mineral oil plasticizer and 0.05 to 0.2 volume percent of a blowing agent selected from the group consisting of hydrocarbon blowing agents and azobisformamide, b. heating the mixture from 200* to 500*F. and extruding the material through a die containing a mandrel to form a tubular extrudate having one or more cavities therein, c. cutting the extrudate into sections and extracting the plasticizer, d. heating to 300* to 700*C. to burn off the polyolefin and, e. sintering at a temperature of 1400* to 1700*C and recovering the product.