Process for oxidizing and carbonizing acrylic fibers
Abstract
Abstract THIS INVENTION PROVIDES A PROCESS FOR PREOXIDIZING ACRYLIC FIBERS WHICH CAN BE CONVERTED INTO CARBON OR GRAPHITE FIBERS OF HIGH STRENGTH AND MODULUS. THE PROCESS INVOLVES FIRST HEATING THE FIBER, WHILE UNDER TENSION, TO A TEMPERATURE BELOW 250*C. IN AN ATMOSPHERE OF OXYGEN AND BROMINE FOR A TIME SUFFICIENT TO FORM A PERMEABLE SHEATH AROUND THE FIBER. THE FIBER IS NEXT HEATED IN AN OXYGEN ATMOSPHERE AT A TEMPERATURE ABOVE 250*C. FOR A TIME SUFFICIENT TO ALLOW COMPLETE PERMEATION OF OXYGEN THROUGHOUT THE CORE OF THE FIBER. THE OXIDIZED FIBERS ARE USEFUL FOR THE CONSTRUCTION OF FIREPROOF FABRICS AND MAY ALSO BE CARBONIZED OR GRAPHITIZED BY HEATING IN AN INERT ATMOSPHERE AT THE APPROPRIATE TEMPERATURES.
Inventors
- 👤 John R Holsten
- 👤 Jerimah G Morrison Jr
Bibliographic Details
Claims Analysis
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