Sensing and actuating capabilities of a shape memory polymer composite integrated withhybrid filler

Abstract

In this paper, hybrid fillers, including carbon black (CB) and chopped short carbon fibers(SCF), are integrated into a styrene-based shape memory polymer (SMP) with sensing andactuating capabilities. The hybrid filler is expected to transform insulating SMP intoconducting. Static mechanical properties of the SMP composites containing various fillerconcentrations of hybrid filler reinforcement are studied first, and it is theoreticallyand experimentally confirmed that the mechanical properties are significantlyimproved by a factor of filler content of SCF. The excellent electrical properties ofthis novel type of SMP composite are determined by a four-point-probe method.As a consequence, the sensing properties of SMP composite filled with 5 wt%CB and 2 wt% SCF are characterized by functions of temperature and strain.These two experimental results both aid the use of SMP composites as sensorsthat respond to changes in temperature or mechanical loads. On the other hand,the actuating capability of SMP composites is also validated and demonstrated.The dynamic mechanical analysis result reveals that the output strength of SMPcomposites is improved with an increase in filler content of SCF. The actuatingcapability of SMP composites is subsequently demonstrated in a series of photographs.