U.S. 8,633,293 B2
GM Global Technology Operations has been granted a patent for a polymer comprised of a reaction product of an epoxy resin; a first crosslinking agent reactive with the epoxy resin and having a first molecular weight; and a second crosslinking agent reactive with the epoxy resin, wherein the second crosslinking agent is an amine having a polyether backbone, at least one amino group attached to the polyether backbone, and a second molecular weight of at least 2.5 times greater than the first molecular weight; wherein the polymer has a first phase having a first glass transition temperature at which the polymer is transformable between a first shape and a second shape; wherein the second crosslinking agent is crystallizable within the polymer and thereby has a melting temperature that is detectable within the polymer; wherein the polyether backbone includes ethylene oxide and propylene oxide.
