Patent ID: 8365833

Claim:
A wellbore device comprising: at least two shape-memory materials: a first shape-memory material having an altered geometric position and an original geometric position, where the shape-memory material is maintained in the altered geometric position at a temperature below a first onset glass transition temperature, and where the shape-memory material expands from its altered geometric position to its recovered geometric position when it is heated to a temperature above the first onset glass transition temperature, where the first shape-memory material has a first slope change during a first transition state from a first glass state to a first rubber state; and a second shape-memory material having an altered geometric position and an original geometric position, where the shape-memory material is maintained in the altered geometric position at a temperature below a second onset glass transition temperature, and where the shape-memory material recovers from its altered geometric position to its recovered geometric position when it is heated to a temperature above the second onset glass transition temperature, where the second shape-memory material has a second slope change during a second transition state from a second glass state to a second rubber state; and where the first shape-memory material and the second shape-memory material each comprise a polyurethane, where the ratios of polyol to polyisocyanate in the polyurethanes of the first and second shape-memory materials are different by a parameter selected from the group consisting of: the first onset glass transition temperature is different from the second onset glass transition temperature, the first slope change is different from the second slope change, and both.