Carbonization/graphitization of poly-acrylonitrile fibers containing residual spinning solvent
Abstract
Abstract A PROCESS IS PROVIDED FOR THE EFFICIENT CONVERSION OF ACRYLONITRILE HOMOPOLYMER FIBROUS MATERIALS AND CLOSELY RELATED ACRYLONITRILE COPOLYMER FIBROUS MATERIAL TO GRAPHITIC FIBROUS MATERIAL OF HIGH TENACITY. THE PROCESS INCORPORATES AN INITIAL BRIEF FIBER HEATING STEP WHICH IS CONDUCTED AT A TEMPERATURE OF ABOUT 170 TO 220*C., A PREOXIDATION STEP, AND A TANDEM CARBONIZATION- GRAPHITIZATION STEP AS DESCRIBED. THE RELATIONSHIP OF THE VARIOUS VARIABLES REQUIRED TO PRODUCE THE HIGH TENACITY GRAPHITIC FIBROUS PRODUCT IS SET FORTH IN THE EQUATION PROVIDED. IN A PREFERRED EMBODIMENT OF THE INVENTION THE CARBONIZATION/GRAPHITIZATION STEP OF THE PROCESS IS CONDUCTED ON A RELIABLE AND STABLE BASIS WHEREIN THE DESIRED TENACITY IS ACHIEVED WITHOUT THE NECESSITYH OF RESORTING TO THE EXERTION OF HIGH LONGITUDINAL TENSIONS UPON THE PREOXIDIZED ACRYLIC FIBROUS MATERIAL. THE FIBERS MAY CONTAIN 2-10 PRECENT RESIDUAL SOLVENT FROM THE FIBER SPINNING OPERATION.
Inventors
- 👤 M Ram
- 👤 A Rosenthal
- 👤 C Clarke
Bibliographic Details
Claims Analysis
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