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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

A study of polyimide films modified with gold

Madeleine, Dennis Gerard January 1988 (has links)
Virginia Polytechnic Institute and State University laboratories have produced a wide variety of polyimide films which have been modified by the incorporation of metal compounds. These polymer/metal composites have potential use as coatings in aerospace applications where enhanced electrical conductivity and thermal stability are desirable. Generally, these materials are produced by heating a polyamic acid solution which contains a soluble metal salt. While the electrical and thermal properties of some of these films have been studied in great detail, little is known about the factors which control the ultimate distribution of metal in the polymer matrix. In this work, the segregation of components in polyimide modified with the gold salt, HAuCl₄·H₂O, is described. Thermal treatment usually promoted three changes in the film: (1) conversion of an initially present polyamic acid to the thermally stable polyimide, (2) reduction of chloroauric acid to metallic gold and (3) redistribution of the metal into gold domains either in the bulk or at a surface of the film. The third event listed above has been termed metalization. Most of the gold modified polyimide I films exhibited bulk metalization as evidenced by the dispersion of very small gold particles through out the film. However, the gold aggregates which comprised the metalized surface layer possessed several different morphologies which indicated that a diffusion limited aggregation processes controlled the aggregate growth. The appearance of these aggregates was central to developing a model of phase separation in these metal modified films. / Ph. D.

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