Controlled motion of solvent-driven gel motor and its application as a generator

Attempts have been made to control the spontaneous random motion of a tetra hydrofuran-swollen amphiphilic polymer gel on a water surface. By allowing the ejection of tetrahydrofuran through spouting holes, the gel showed an i mproved translational motion with a velocity of 77 mm/s or rotation with a rotation rate of 394 rpm. The controlled rotation showed an energy efficien cy of 4.5 x 10(-3)%, which was 10 times of that of random motion. On the ba sis of the improved rotational motion of the gel, a generator consisting of a gel rotor equipped with a pair of permanent magnets and a solenoid coil has been constructed. The generator rotor which was 40 mm long, 6 mm wide, and 2 mm thick, produced an alternative electric power with an instantaneou s electromotive force as high as 15mV for a period of over 30 min. Such beh aviors as the controlled motion, the spreading rate of tetrahydrofuran on t he water surface, the crystallization and texture of gel surfaces, and the power generated have been described.