Untersuchungen zur Herstellung von Kohlenstoffasern auf der Basis von mit Wasserstoffperoxid Modifizierten Pan-Fasern

✍ Scribed by N. Popovska; I. Mladenov

• Publisher: Elsevier Science
• Year: 1983
• Tongue: English
• Weight: 636 KB
• Volume: 21
• Category: Article
• ISSN: 0008-6223
• DOI: 10.1016/0008-6223(83)90153-7

✦ Synopsis

Chemical transformations of PAN fibres "Bulana" (mass fractions: 93% acrylonitrile, 6% methylmethacrylate and 1% Na-vinylsulphonate) were studied as resulting from its treatment with hydrogen peroxide in alkaline medium, a first step of carbon fibre production. The reaction proceeds in formation of amide groups under the given experimental conditions. Simultaneously, cyclisation and network formation take place. The gel fraction is found to be 88%. As a result of the modification, a decrease in the temperature of initiation of the stabilizing reactions, as well as a decrease in the enthalpy AH from 885 J/g to 811 Jig are observed. The activation energy calculated by Kissinger's method is I48 kJ/mol in the case of the PAN fibres, and 108 kJ/mol for the treated fibres.

The modification of PAN fibres by hydrogen peroxide in alkaline medium accelerates the next step of air oxidation. The modified PAN carbon fibres reach by oxidation their highest strength without shrinkage. The highest