抄録
Shape memory polymers (SMP) have excellent properties including light weight, large deformations, and easy formability to form arbitrary shapes. In particular, polyurethane series SMPs work stably and have the added advantage of being able to tailor the glass transition temperature (Tg) to an arbitral temperature. We applied the polyurethane series SMPs to MEMS actuators. However, for SMP actuators, after the memory shape is formed, it is necessary to return it back to the original shape by some method. We used two kinds of SMPs with different glass transition temperatures (Tgi, Tg2, Tgl<Tg2) and used the memory shape of Tg2 for canceling the memory shape of Tgi by making the memory shapes of Tg2 reverse of that of Tgi. We applied this mechanism to cantilever beam samples coated with SMP layers on the surface. We confirmed that the beam deforms around To and then the deformation disappears around Tg2. Arrayed actuators with unified thin-film heaters are also proposed.
