Process for extruding an article from an amide-imide copolymer and the resultant article

Claim 2

A process for extruding an article from an amide-imide copolymer, said process comprising: (a) feeding said amide-imide copolymer and an external lubricant into a corotating, intermeshing twin-screw extruder, said extruder having a barrel temperature of about 450° to about 600° F.; (b) melting said amide-imide copolymer between flights of corotating, intermeshing screws of said extruder to form an amide-imide copolymer melt; (c) passing said amide-imide copolymer melt into a melt channel of an extrusion die, said die being attached to the exit of said extruder; (d) heating said extrusion die to maintain the copolymer as a melt; (e) passing said copolymer melt through said melt channel, said melt channel having a geometry which provides a constantly increasing shear rate in said copolymer melt; (f) extruding said copolymer melt out of the exit of said extrusion die, said exit having a shape to form said article in molten form; and (g) solidifying the molten form after it has been extruded from said die to provide said article.

Claim 3

The process of claim 1 wherein said amide-imide copolymer comprises units of: ##STR15## and units of: ##STR16## wherein one carbonyl group is meta to and one carbonyl group is para to each amide group and wherein Z is a trivalent benzene ring or lower-alkyl-substituted trivalent benzene ring, R 1 and R 2 are different and are divalent aromatic hydrocarbon radicals of from about 6 to about 10 carbon atoms or two divalent aromatic hydrocarbons joined directly or by stable linkages selected from the group consisting of --O--, methylene, --C--, --SO 2 --, and --S-- radicals and where said R 1 and R 2 containing units run from about 10 mole percent R 1 containing unit and about 90 mole percent R 2 containing unit to about 90 mole percent R 1 containing unit and about 10 mole percent R 2 containing unit.

Claim 4

The process according to claim 2 wherein the extruded article is a thin film of about 1 to about 15 mils in thickness.

Claim 5

The process of claim 2 wherein the extruded article is in the form of a sheet of about 10 to about 250 mils in thickness.

Claim 6

The process of claim 2 wherein the extruded article is in the form of a hollow tube with an outside diameter of about 0.25 inch to about 2 inches and a wall thickness of about 0.05 inch to about 0.25 inch.

Claim 7

The process of claim 2 wherein the shear rate is about 0.5 per second to about 200 per second.

Claim 8

The process of claim 1 wherein the external lubricant is polytetrafluoroethylene.

Claim 9

The process of claim 6 wherein about 1 to about 2 percent by weight of the total copolymer is tetrafluoroethylene.

Claim 10

The process of claim 2 wherein about 0.1 to about 50 percent by weight polyetherimide is added to the copolymer prior to extrusion.

Claim 11

The process of claim 9 wherein the polyetherimide is of the following formula: ##STR17## where R is a member selected from the class consisting of (a) the following divalent organic radicals: ##STR18## and (b) divalent organic radicals of the general formula: ##STR19## where X is --C y H 2y --, Y is a whole number equal to from 1 to 5, inclusive, and R 1 is a divalent organic radical selected from the class consisting of (a) aromatic hydrocarbon radicals having from 6-20 carbon atoms and halogenated derivatives thereof, (b) alkylene radicals and cycloalkylene radicals having from 2-20 carbon atoms, (c) C.sub.(2-8) alkylene terminated polydiorganosiloxanes, and (d) divalent radicals included by the formula: ##STR20## where Q is a member selected from the class consisting of: ##STR21## and x is a whole number equal to from 1 to 5, inclusive.

Claim 12

The process of claim 2 wherein about 0.1 to about 50 percent by weight of polysulfone is added to the copolymer prior to extrusion.

Claim 13

The process of claim 11 wherein the polysulfones comprise recurring units of the following structure: ##STR22##

Claim 14

The process of claim 1 wherein said external lubricant comprises about 0.5 to about 3 weight percent based on said copolymers.

Claim 15

The process of claim 1 wherein said shear rate increases from about 0.1 per second to about 2000 per second.

Claim 16

The process of claim 1 wherein said amide-imide copolymer comprises A units of: ##STR23## wherein the free carboxyl groups are ortho to one amide group and comprises B units of: ##STR24## wherein one carbonyl group is meta to, and one carbonyl group is para to each amide group and wherein Z is a trivalent benzene ring or lower-alkyl-substituted trivalent benzene ring, R 1 and R 2 are different and are divalent aromatic hydrocarbon radicals of about 6 to about 10 carbon atoms or two divalent aromatic hydrocarbon radicals of from 6 to about 10 carbon atoms joined directly or by stable linkages selected from the group consisting of --O--, methylene, --CO--, --SO 2 --, and --S-- radicals and wherein the proportions of A and B units run from about 1 mole percent A units and about 99 mole percent B units to about 99 mole percent A units and about 1 mole percent B units and wherein the R 1 and R 2 containing components of the A and B units run from about 10 mole percent R 1 containing components and about 90 mole percent R 2 containing components to about 90 mole percent R 1 containing components and about 10 mole percent R 2 containing components.

Claim 17

The process of claim 15 wherein said external lubricant comprises about 0.5 to about 3 weight percent based on said copolymers.

Claim 18

The process of claim 15 wherein said shear rate increases from about 0.1 per second to about 2000 per second.

Claim 19

A process for extruding an article comprising: (a) feeding an amide-imide copolymer and about 0.5 to about 3.0 percent by weight of polytetrafluoroethylene into a corotating, intermeshing twin-screw extruder having a barrel temperature of about 450° to about 680° F., wherein a major proportion of said amide-imide copolymer comprises a repeating structural unit represented by the formula ##STR25## (b) melting said amide-imide copolymer between flights of corotating, intermeshing screws of said extruder to form an amide-imide copolymer melt; (c) passing said amide-imide copolymer melt into a melt channel of an extrusion die which is attached to the exit of said extruder; (d) heating said extrusion die to a temperature of about 550° to about 680° F. to maintain the copolymer as a melt; (e) passing said copolymer melt through said melt channel, said melt channel having a geometry which imparts a constantly increasing shear rate of about 0.1 per second to about 2000 per second to the copolymer melt being extruded through the melt channel; (f) extruding said copolymer melt out of the exit of said extrusion die, said exit having a shape to form said article in molten form; and (g) solidifying the molten form after it has been extruded from said die to provide said article.

Claim 20

A process for extruding an article comprising: (a) feeding an amide-imide copolymer and about 0.5 to about 3.0 percent by weight of polytetrafluoroethylene into a corotating, intermeshing twin-screw extruder having a barrel temperature of about 450° to about 680° F., wherein a major proportion of said amide-imide copolymer comprises a repeating structural unit represented by the formula ##STR25## (b) melting said amide-imide copolymer between flights of corotating, intermeshing screws of said extruder to form an amide-imide copolymer melt; (c) passing said amide-imide copolymer melt into a melt channel of an extrusion die which is attached to the exit of said extruder; (d) heating said extrusion die to a temperature of about 550° to about 680° F. to maintain the copolymer as a melt; (e) passing said copolymer melt through said melt channel, said melt channel having a geometry which imparts a constantly increasing shear rate of about 0.1 per second to about 2000 per second to the copolymer melt being extruded through the melt channel; (f) extruding said copolymer melt out of the exit of said extrusion die, said exit having a shape to form said article in molten form; and (g) solidifying the molten form after it has been extruded from said die to provide said article.

Claim 21

The process according to claim 15 wherein the extruded article is a thin film of about 1 to about 15 mils in thickness.

Claim 22

The process of claim 15 wherein the extruded article is in the form of a sheet of about 10 to about 250 mils in thickness.

Claim 23

The process of claim 15 wherein the extruded article is in the form of a hollow tube with an outside diameter of about 0.25 inch to about 2 inches and a wall thickness of about 0.05 inch to about 0.25 inch.

Claim 24

The process of claim 15 wherein the shear rate is about 0.5 per second to about 200 per second.

Claim 25

The process of claim 15 wherein the external lubricant is polytetrafluoroethylene.

Claim 26

The process of claim 15 wherein about 1 to about 2 percent by weight of the total copolymer is tetrafluoroethylene.

Claim 27

The process of claim 15 wherein about 0.1 to about 50 percent by weight polyetherimides are added to the copolymer prior to extrusion.

Claim 28

The process of claim 15 wherein the polyetherimide is of the following formula: ##STR26## where R is a member selected from the class consisting of (a) the following divalent organic radicals: ##STR27## and (b) divalent organic radicals of the general formula: ##STR28## where X is --C y H 2y --, Y is a whole number equal to from 1 to 5, inclusive, and R 1 is a divalent organic radical selected from the class consisting of (a) aromatic hydrocarbon radicals having from 6-20 carbon atoms and halogenated derivatives thereof, (b) alkylene radicals and cycloalkylene radicals having from 2-20 carbon atoms, (c) C.sub.(2-8) alkylene terminated polydiorganosiloxanes, and (d) divalent radicals included by the formula: ##STR29## where Q is a member selected from the class consisting of: ##STR30## and x is a whole number equal to from 1 to 5, inclusive.

Claim 29

The process of claim 15 wherein about 0.1 to about 50 percent by weight of polysulfones are added to the copolymer prior to extrusion.

Claim 30

The process of claim 27 wherein the polysulfones comprise recurring units of the following structure: ##STR31##

Claim 31

The process of claim 2 wherein R 1 of the copolymer is ##STR32## and R 2 is ##STR33## or wherein R 1 is ##STR34## and R 2 is ##STR35##

Claim 32

The process of claim 9 wherein R 1 of the copolymer is ##STR36## and R 2 is ##STR37## or wherein R 1 is ##STR38## and R 2 is ##STR39##

Claim 33

The process of claim 15 wherein R 1 of the copolymer is ##STR40## and R 2 is ##STR41## or wherein R 1 is ##STR42## and R 2 is ##STR43##

Claim 34

The process of claim 2 wherein Z of the copolymer is a trivalent benzene ring, R 1 is ##STR44## and R 2 is ##STR45## and wherein the concentration range runs from about 30 mole percent of the R 1 containing units and about 70 mole percent of the R 2 containing units to about 70 mole percent of the R 1 containing units and about 30 mole percent of the R 2 containing units.

Claim 35

The process of claim 15 wherein Z of the copolymer is a trivalent benzene ring, R 1 is ##STR46## and R 2 is ##STR47## and wherein the concentration range runs from about 30 mole percent of the R 1 containing units and about 70 mole percent of the R 2 containing units to about 70 mole percent of the R 1 containing units and about 30 mole percent of the R 2 containing units.

Claim 36

The process of claim 11 wherein R 1 of the copolymer is ##STR48## and R 2 is ##STR49## or wherein R 1 is ##STR50## and R 2 is ##STR51##

Claim 37

As an article of manufacture, a thin film of about 1 to about 15 mils thickness prepared by the process of claim 2.

Claim 38

As an article of manufacture a sheet of about 10 to about 250 mils in thickness prepared by the process of claim 2.

Claim 39

A hollow tube with outside diameter of about 0.25 inch to about 2 inches and a wall thickness of about 0.05 inch to about 0.25 inch prepared by the process of claim 2.

Claim 40

An an article of manufacture, a thin film of about 1 to about 15 mils thickness prepared by the process of claim 15.

Claim 41

As an article of manufacture a sheet of about 10 to about 250 mils in thickness prepared by the process of claim 15.

Claim 42

A hollow tube with outside diameter of about 0.25 inch to about 2 inches and a wall thickness of about 0.05 inch to about 0.25 inch prepared by the process of claim 15.