Dielectric behavior and resistivities of polyacrylonitrile and some pyrolyzates

✍ Scribed by L. K. H. Van Beek

• Publisher: John Wiley and Sons
• Year: 1965
• Tongue: English
• Weight: 371 KB
• Volume: 9
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/app.1965.070090217

✦ Synopsis

Dielectric losses in polyacrylonitrile (PAN) and three pyrolyzates were studied between 1 Ha. and 300 kHz. Pure PAN has at 20°C. a very broad low region with a maximum at 70 HI. which is ascribed to CN groups. Powdered PAN was pyrolyzed in a nitrogen atmosphere at 170, 220, and 300OC. PAN-170 has the same loss maximum as the unpyrolyzed polymer, but the maximum had disappeared in PAN-220. This ia ab tributed to formation of conjugated chains by liking of CN groups above 200°C. However, this does not enhance the conductivity until hydrogen is eliminated above 350°C.