Production of resin impregnated fibrous graphite ribbons

Claim 2

A process according to claim 1 wherein said multifilament bundles of a fibrous material capable of undergoing graphitization are derived from a fibrous material selected from the group consisting of an acrylonitrile Homopolymer and acrylonitrile copolymers which contain at least about 85 mol percent of acrylonitrile units and up to about 15 mol percent of one or more monovinyl units copolymerized therewith.

Claim 3

A process according to claim 1 wherein said multifilament bundles of fibrous material capable of undergoing graphitization are passed through said graphitization zone at a temperature of about 2,400* to 3,100* C.

Claim 4

A process according to claim 1 wherein said multifilament bundles are continuous multifilament yarns having essentially no twist.

Claim 5

A process according to claim 1 wherein said multifilament bundles are continuous multifilament yarns having a twist of about 0.1 to 5 tpi.

Claim 6

A process according to claim 1 wherein said thermosetting resin is an epoxy resin.

Claim 7

A process for the continuous production of a resin impregnated graphite ribbon for use in the manufacture of fiber reinforced composites comprising: a. continuously passing a plurality of substantially uniform multifilament bundles of a fibrous material capable of undergoing graphitization while in an adjoining essentially parallel relationship and in the form of a ribbon having a thickness corresponding to that of a single multifilament bundle with each bundle being under a substantially uniform tension through a graphitization zone at a temperature of about 2,000* to 3,100* C. and containing an inert atmosphere for a residence time sufficient to substantially convert said bundles to graphitic carbon while retaining their original fibrous configuration essentially intact, b. continuously feeding the resulting bundles of graphitic carbon from said graphitization zone to a coating zone, c. continuously passing said bundles of graphitic carbon through said coating zone while retaining said adjoining essentially parallel relationship of said bundles and said ribbon configuration having a thickness corresponding to that of a single multifilament bundle with each bundle being under a substantially uniform tension wherein said bundles are coated with a solventless system comprising an A-stage thermosetting resin, d. continuously feeding said coated ribbon from said coating zone to a heating zone while retaining said adjoining essentially parallel relationship of said bundles within said ribbon, e. continuously passing said coated ribbon through said heating zone wherein said A-stage thermosetting resin present on said ribbon is converted to B-stage thermosetting resin while retaining said adjoining essentially parallel relationship of said bundles within said ribbon, and f. continuously withdrawing said coated graphite ribbon from said heating zone while said thermosetting resin present on said ribbon is a B-stage thermosetting resin.

Claim 8

A process according to claim 8 wherein said plurality of multifilament bundles of a fibrous material capable of undergoing graphitization contain at least about 90 percent carbon by weight and exhibit an essentially amorphous X-ray diffraction pattern.

Claim 9

A process according to claim 9 wherein said multifilament bundles of a fibrous material capable of undergoing graphitization are derived from a fibrous material selected from the group consisting of an acrylonitrile homopolymer and acrylonitrile copolymers which contain at least about 85 mol percent of acrylonitrile units and up to about 15 mol percent of one or more monovinyl units copolymerized therewith.

Claim 10

A process according to claim 8 wherein said multifilament bundles of fibrous material capable of undergoing graphitization are passed through said graphitization zone at a temperature of about 2,400* to 3,100* C.

Claim 11

A process according to claim 9 wherein said multifilament bundles are continuous multifilament yarns having essentially no twist.

Claim 12

A process according to claim 9 wherein said multifilament bundles are continuous multifilament yarns having a twIst of about 0.3 to 1.0 tpi.

Claim 13

A process according to claim 9 wherein said solventless system comprising an A-stage thermosetting resin comprises an A-stage epoxy resin and a curing agent for said epoxy resin.

Claim 14

A process according to claim 14 wherein said epoxy resin is a condensation product of bisphenol A and epichlorohydrin.

Claim 15

A process for the continuous production of a resin impregnated graphite ribbon for use in the manufacture of fiber reinforced composites comprising: a. continuously passing while in an adjoining essentially parallel relationship and in the form of a ribbon having a thickness corresponding to that of a single multifilament bundle a plurality of substantially uniform multifilament bundles of a stabilized acrylic fibrous material with each bundle being under a substantially uniform tension having a temperature within the range of about 20* to 500* C. which is non-burning when subjected to an ordinary match flame and derived from an acrylic fibrous material selected from the group consisting of an acrylonitrile homopolymer and acrylonitrile copolymers which contain at least about 85 mol percent of one or more monovinyl units copolymerized therewith through a carbonization heating zone provided with an inert atmosphere in which said bundles of stabilized acrylic fibrous material are raised within a period of about 3 seconds to about 10 minutes to a temperature within the range of about 900* C. to about 1,600* C. wherein a carbonized ribbon is formed, b. continuously passing said carbonized ribbon through a graphitization heating zone provided with an inert atmosphere while retaining said adjoining parallel relationship of said bundles within said ribbon with each bundle being under a substantially uniform tension in which said carbonized ribbon is heated at a temperature within the range of about 2,000* to 3,100* C. for a residence time sufficient to substantially convert said bundles to graphitic carbon, c. continuously feeding the resulting bundles of graphitic carbon from said graphitization heating zone to a coating zone, d. continuously passing said bundles of graphitic carbon through said coating zone while retaining said adjoining essentially parallel relationship of said bundles and said ribbon configuration having a thickness corresponding to that of a single multifilament bundle with each bundle being under a substantially uniform tension wherein said ribbon is impregnated with a thermosetting resin, and e. withdrawing the resulting resin impregnated graphite ribbon from said coating zone.

Claim 16

A process according to claim 16 wherein said multifilament bundles are continuous multifilament yarns having essentially no twist.

Claim 17

A process according to claim 16 wherein said multifilament bundles are continuous multifilament yarns having a twist of about 0.1 to 5 tpi.

Claim 18

A process according to claim 16 wherein said multifilament bundles of stabilized acrylic fibrous material are derived from an acrylonitrile homopolymer.

Claim 19

A process according to claim 16 wherein said carbonized ribbon is continuously passed through a graphitization heating zone at about 2,400* to 3,100* C. for a residence time sufficient to convert said bundles forming the same to graphitic carbon.

Claim 20

A process for the continuous production of a resin impregnated graphite ribbon for use in the manufacture of fiber reinforced composites comprising: a. continuously passing while in an adjoining essentially parallel relationship and in the form of a ribbon having a thickness corresponding to that of a single multifilament bundle a plurality of substantially uniform multifilament bundles of a stabilized acrylic fibrous material with each bundle being under a substantially uniform tension having a temperature within the range of about 20* to 500* C. Which is non-burning when subjected to an ordinary match flame and derived from an acrylic fibrous material selected from the group consisting of an acrylonitrile homopolymer and acrylonitrile copolymers which contain at least about 85 mol percent of acrylonitrile units and up to about 15 mol percent of one or more monovinyl units copolymerized therewith through a carbonization heating zone provided with an inert atmosphere in which said bundles of stabilized acrylic fibrous material are raised within a period of about 3 seconds to about 10 minutes to a temperature within the range of about 900* C. to about 1,600* C. wherein a carbonized ribbon is formed, b. continuously passing said carbonized ribbon through a graphitization heating zone provided with an inert atmosphere while retaining said adjoining parallel relationship of said bundles within said ribbon with each bundle being under a substantially uniform tension in which said carbonized ribbon is heated at a temperature within the range of about 2,400* to 3,100* C. for a residence time sufficient to substantially convert said bundles to graphitic carbon, c. continuously feeding the resulting bundles of graphitic carbon from said graphitization heating zone to a coating zone, d. continuously passing said bundles of graphitic carbon through said coating zone while retaining said adjoining essentially parallel relationship of said bundles and said ribbon configuration having a thickness corresponding to that of a single multifilament bundle with each bundle being under a substantially uniform tension wherein said ribbon is coated with a solventless system comprising an A-stage thermosetting resin, e. continuously feeding said coated ribbon from said coating zone to a heating zone while retaining said adjoining essentially parallel relationship of said bundles within said ribbon, f. continuously passing said coating ribbon through said heating zone wherein said A-stage thermosetting resin present on said ribbon is converted to B-stage thermosetting resin while retaining said adjoining essentially parallel relationship of said bundles within said ribbon, and g. continuously withdrawing said coated graphite ribbon from said heating zone while said thermosetting resin present on said ribbon is a B-stage thermosetting resin.

Claim 21

A process according to claim 21 wherein said stabilized acrylic fibrous material is derived from an acrylonitrile homopolymer.

Claim 22

A process according to claim 21 wherein said solventless system comprising an A-stage thermosetting resin comprises an A-stage epoxy resin and a curing agent for said epoxy resin.

Claim 23

A process according to claim 22 wherein said A-stage epoxy resin is a condensation product of bisphenol A and epichlorohydrin.