Charge formation in polyimide films under the action of low-frequency glow-discharge plasma

Journal Article · Sat Jul 01 04:00:00 EDT 1995 · High Energy Chemistry

OSTI ID:171694

Drachev, A I; Gil`man, A B; Tuzov, L S; Potapov, V K ^[1]

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1. Karpov Institute of Physical Chemistry, Moscow (Russian Federation)

The authors showed previously that treatment of the surface of PM polyimide films (produced in Russia) with a low-frequency (LF) glow-discharge plasma resulted in considerable changes in their wettability and surface energy. Similar results were also obtained abroad for Kapton films. It was shown that the formation of polar NH and OH groups (in unbound carboxyl groups) occurred in the surface layer as a result of decyclization processes. In addition, the concentration of free radicals was shown to increase. These changes in chemical structure are probably responsible for increasing the hydrophilicity of the surface of polyimide films. However, estimations showed that the concentrations of free radicals were comparatively low. Apparently, the significant changes of the polar component of the surface energy that were observed (by 2-3 orders of magnitude) cannot be fully explained by the formation of radicals. The study of the effect of LF glow discharge on polytetrafluoroethylene revealed an essential decrease of the contact angles on the film surface and formation of the surface electric charge. It was shown that the neutralization of this charge resulted in increased contact angles for polytetrafluoroethylene nearly up to the values for the original films. Thus, the charged (or electret) states appear to play an important part in modifying the energetic characteristics of the film surface in the case of polytetrafluoroethylene. Similar states may also result from the glow-discharge treatment of polyimide and play a certain part in modifying the surface characteristics of this polymer. In this work the authors carried out measurements of the charge generated in polyimide films modified with glow discharge and investigated the mechanism of charge accumulation in the samples.

• OSTI ID: 171694
• Journal Information: High Energy Chemistry, Journal Name: High Energy Chemistry Journal Issue: 4 Vol. 29; ISSN 0018-1439; ISSN HIECAP
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CHARGE COLLECTION
FILMS
GLOW DISCHARGES
IMIDES
ORGANIC POLYMERS
PLASMA
RADICALS