Process for the formation of stabilized and carbonized acrylic fibrous material
Abstract
Abstract AN IMPROVED PROCESS IS PROVIDED FOR THE FORMATION OF FIBROUS MATERIALS OF ENHANCED THERMAL STABILITY DERIVED FROM ACRYLIC POLYMERS CONSISTING PRIMARILY OF RECURRING ACRYLONITRILE UNITS. A MINOR QUANTITY OF A LEWIS ACID CAPABLE OF PROMOTING THE CYCLIZATION OF PENDANT NITRILE GROUPS IS INCORPORATED IN A SOLUTION OF THE ACRYLIC POLYMER, A CYCLIZED ACRYLIC MATERIAL IS FORMED WITHIN THE SOLUTION AT AN ELEVATED TEMPERATURE, THE RESULTING SOLUTION IS SPUN TO FORM A CYCLIZED ACRYLIC FIBROUS MATERIAL WHICH IS SOLUBLE IN,N-DIMETHYLFORMAMIDE, AND THE RESULTING CYCLIZED ACRYLIC FIBROUS MATERIAL IS HEATED IN AN OXYGENCONTAINING ATMOSPHERE UNTIL A STABILIZED FIBROUS PRODUCT IS FORMED WHICH IS CAPABLE OF UNDERGOING CARBONIZATION AND WHICH IS INSOLUBLE IN N,N-DIMETHYLFORMAMIDE. THE STABILIZED FIBROUS MATERIAL MAY NEXT OPTIONALLY BE CARBONIZED OR CARBONIZED AND GRAPHITIZED AT ELEVATED TEMPERATURES WHILE PRESENT IN AN INERT ATMOSPHERE.
Inventors
- 👤 K Gump
- 👤 D Stuetz
Bibliographic Details
Claims Analysis
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