Polyurethane nanocomposites

摘要

Polyurethane nanocomposites are provided which include a polyurethane and surface modified silica nanoparticles covalently bound into the polyurethane. High loadings in excess of 30% may be achieved. In some embodiments, the silica nanoparticles are covalently bound to the polyurethane polymer through a linkage derived from a surface-modifying compound comprising a silane functional group and a polyol segment. In some embodiments the polyurethane nanocomposite may be provided as a tape or film. In addition, precursors for a polyurethane nanocomposites are provided comprising: a first polyol and surface modified silica nanoparticles dispersed within the first polyol. In some embodiments, the silica nanoparticles are surface-modified by reaction with a surface-modifying compound comprising a silane functional group and a polyol segment derived from a second polyol, which may be the same or different from the first polyol.

主权项

1. An erosion resistant film comprising a polyurethane nanocomposite comprising:
a) a polyurethane polymer, and b) surface modified silica nanoparticles dispersed within and covalently bound to the polyurethane polymer;wherein the silica nanoparticles are covalently bound to the polyurethane polymer through a linkage derived from a first surface-modifying compound comprising a polyol to which a silane group is added by reaction with a compound comprising a silane or silane-generating group and an isocyanate group; andwherein said silica nanoparticles have a number average particle size of between 10 and 200 nanometers (nm); wherein the polyurethane nanocomposite has a silica content of greater than 12% by weight.