Giant Bending Strain of Reversible Motion of Uni-Morph Soft Mover Composites Driven by Hydrogen Storage Alloy Powders Dispersed in Polyurethane Sheet

摘要

In order to generate the bending motion operated by pressure change in hydrogen gas, soft uni-morph composites were prepared, in which composites dispersed with not only driving particles of LaNi_5 hydrogen storage alloy with Pd-Al_2O_3 catalyst powders to get high responsiveness, were piled up on a simple polyurethane sheet. Since the highest values of irreversible bending strain at the first hydrogenation (epsilon~1) under 0.3 MPa H_2 gas and the maximum irreversible bending strain during hydrogenation cycles (epsilon~m) were remarkably obtained at the 35 vol percent of LaNi_5 powders dispersed in polyurethane composites, the bending strain of reversible motion was detected from the first to the 8th hydrogenation (epsilon_r~1 and epsilon_r~8) under 0.2MPa H_2 gas. The bending strain of reversible motion of polyurethane composites sheet is more than 2000 ppm, which was approximately equal to that of silicone rubber composites and is extremely larger than that (300 ppm) of ABS resin composites. Responsiveness (ds/dt) of cyclic motion of elastic deformed mover composites, which were constructed with 35 vol percentLaNi_5 dispersed powder and matrix of polyurethane or silicone rubber, were more than 10 times higher than that of ABS composite.