Improved mica groundwall insulation via grafted polymers

Exploratory work done in an attempt to improve the surface wetting characteristics of mica for high voltage insulation by "grafting" (i.e., chemically reacting) polymer structures to the mica surface is described. Two different experimental approaches to grafting are evaluated, i.e., by chemical reaction; and by plasma polymerization. Both methods give promising results. Evidence for actual polymer grafting to the mica surface is found from IR spectral data, higher tensile strengths and improved wetting to the mica surface. The future direction for this work is discussed and suggestions are given as to how these grafting procedures could possibly be used on a large scale to produce improved mica products suitable for commercial use in high voltage insulation for motors and generators