INTRINSICALLY CONDUCTING ELASTOMERS AS GAP FILLING MATERIALS

Development of a gap filling, electrically conductive elastomer is proposed. The elastomer will consist of a two-phase mixture of an elastomeric aircraft sealant and an intrinsically conducting polymer. The principal innovations are the use of polymerization induced phase separation to create a fibrous second phase of the conducting polymer and the use of an acid-catalyzed polymerization process for the elastomeric oligomer that also serves to in situ dope the conducting polymer. Advantages of this system over those incorporating metal-particle-loaded elastomers include: the relatively low loading of the conductive polymer necessary to achieve electrical continuity' reduction or elimination of plasticizing solvent' increased transmission ultraviolet (uv), visible (vis), and electron beam (EB) radiation for rapid, photoinitiated curing; and the use of compositions which have a high fraction of the elastomer phase which promotes fatigue resistance and chemical stability. The objective of the Phase I program is to demonstrate a conductive elastomer prepared from polydisulfide, and related oligomers, blended with one of several intrinsically conducting polymers including polyaniline and polythiophene. The elastomers will be characterized by electrical conductivity measurements, ultraviolet-visible spectroscopy, and structurally by FT-IR, NMR, and GC-MS measurements.