Artificial muscles based on coiled UHMWPE fibers with shape memory effect

Ultra-high molecular weight polyethylene (UHMWPE) fibers drawn at drawing ratio of 6 (pre-deformation strain 500%) demonstrating the obtained one-way shape memory effect.Artificial muscles have been manufactured in the form of coiled UHMWPE fibers.Isometric recovery stress and recovery strain of the fibers were measured during heating by using a dynamic mechanical analyzer (DMA).As a result, the fibers were capable to demonstrate large contraction of 78% (recovery strain of 93%) due to the entropic elasticity.The recovery stresses of the fibers reach up to 27 MPa.The work of stroke cycle for coiled artificial muscles with a constant stress of 1 MPa was recorded.Artificial muscles based on coiled UHMWPE fibers have a large stroke of 64 %.The structural mechanisms of muscle-like behavior were discussed.