Patent ID: 7361292

Claim:
A composition comprising: a) from about 25 to about 55 percent of one or more isocyanate functional polyether based prepolymers containing one or more organic based polymers dispersed therein having a free isocyanate content of about 0.8 to about 2.2 percent by weight based on the weight of the prepolymer; b) from about 0.5 to about 10 percent of one or more isocyanate functional polyester based prepolymers which is solid at 23° C.; c) from about 1 to about 8 percent of one or more polyisocyanates having a nominal functionality of about 3 or greater; d) from about 10 to about 18 percent of one or more conductive carbon blacks in an amount such that the composition has a dielectric constant of about 15 or less; and e) from about 0.005 to about 2 percent one or more catalysts for the reaction of isocyanate moieties with hydroxyl groups; wherein the percentages are based on the weight of the composition and the composition demonstrates upon cure a modulus of 2.0 MPa or greater at 25° C. measured according to ASTM D4065; a dielectric constant of about 15 or less; a sag of an uncured sample of less than 2 mm, a press flow viscosity of about 20 to about 50 and a storage modulus of about 5.3×10 5 Pa or greater.