Thermally-powered polymer fiber actuators and articles including same
Actuators (artificial muscles) comprising twisted polymer fibers generate actuation when powered thermally. In some embodiments, the thermally-powered polymer fiber actuator can be incorporated into an article, such as a textile or garment.
1 . A thermally-powered polymer fiber actuator comprising a twisted polymer fiber or yarn, wherein
(a) the thermally-powered polymer fiber actuator has a first length at a first temperature;
(b) the thermally-powered polymer fiber actuator has a second length at a second temperature;
(c) the first length and the second length are different in length by at least 5%;
(d) the thermally-powered polymer fiber actuator is operable to reversibly actuate; and
(e) the thermally-powered polymer fiber actuator is a thermally-powered, non-electrochemically-powered, and non-electroactively-powered, polymer fiber actuator.
2 . The thermally-powered polymer fiber actuator of claim 1 , wherein
(a) the thermally-powered polymer fiber actuator has the first length at the first temperature at an applied load; and
(b) the thermally-powered polymer fiber actuator has the second length at the second temperature at the applied load.
3 . The thermally-powered polymer fiber actuator of claim 2 , wherein the thermally-powered polymer fiber actuator has a third length at a third temperature at the applied load, the third temperature being between the first temperature and the second temperature, and the third length being between the first length and second length.
4 . The thermally-powered polymer fiber actuator of claim 2 , wherein the actuator is operable in a continuous range.
5 . The thermally-powered polymer fiber actuator of claim 1 , wherein the thermally-powered polymer fiber actuator has no applied load.
6 . The thermally-powered polymer fiber actuator of claim 1 , wherein the polymer fiber has polymer chains on the surface that are aligned along a direction having an angle of at least 20° relative to the axis of the twisted polymer fiber or yarn.
7 . The thermally-powered polymer fiber actuator of claim 1 , wherein the actuation of the polymer fiber actuator exhibits the substantial absence of hysteresis.
8 . The thermally-powered polymer fiber actuator of claim 1 , wherein the actuation of the polymer fiber actuator exhibits less than 2° C. hysteresis.
9 . The thermally-powered polymer fiber actuator of claim 1 , wherein the twisted polymer fiber or yarn comprises a twisted and coiled polymer fiber or yarn.
10 . An article comprising the thermally-actuating polymer fiber actuator of claim 1 , wherein the article is a textile or a garment.
11 . The article of claim 10 , wherein the article is a textile.
12 . The article of claim 11 , wherein the thermally-actuating polymer fiber actuator has a twisted polymer fiber or yarn that comprises a twisted and coiled polymer fiber or yarn.
13 . The article of claim 10 , wherein the article is a garment.