REVERSIBLE SHAPE MEMORY POLYMERS EXHIBITING AMBIENT ACTUATION TRIGGERING

摘要

Shape memory polymers featuring reversible actuation capability under ambient stimulus for integration with apparel. One approach is to use a multiblock polymer consisting of two (or potentially more) blocks in which the one block is the crystalline switching block with relatively low melting transitions, the other block has a higher thermal transition, and the two blocks are linked together by a linker molecule. Another approach is to use a graft copolymer having high and low melting transitions where the graft copolymer has a first polymer serving as the backbone and a second polymer being grafted to or from the backbone at certain graft locations. A further approach is to use latent crosslinking of a semicrystalline polymer with reactive groups placed on the backbone. Finally, these polymers may be formed as actuators that undergo curling, twisting and even volumetric expansion.