Mechanical and shape‐memory behavior of shape‐memory polymer composites with hybrid fillers

Abstract

Shape‐memory polymer (SMP) materials have several drawbacks such as low strength, low stiffness and natural insulating tendencies, which seriously limit their development and applications. Much effort has been made to improve their mechanical properties by adding particle or fiber fillers to reinforce the polymer matrix. However, this often leads to the mechanical properties being enhanced slightly, but the shape‐memory effect of reinforced SMP composites being drastically reduced. The experimental results reported here suggested that the mechanical resistive loading and thermal conductivity of a composite (with hybrid filler content of 7.0 wt%) were improved by 160 and 200%, respectively, in comparison with those of pure bulk SMP. Also, the glass transition temperature of the composite was enhanced to 57.28 °C from the 46.38 °C of a composite filled with 5.5 wt% hybrid filler, as determined from differential scanning calorimetry measurements. Finally, the temperature distribution and recovery behavior of specimens were recorded with infrared video in a recovery test, where a 28 V direct current circuit was applied. The effectiveness of carbon black and short carbon fibers being incorporated into a SMP with shape recovery activated by electricity has been demonstrated. These hybrid fillers were explored to improve the mechanical and conductive properties of bulk SMP. Copyright © 2010 Society of Chemical Industry

Synergistic effect of Ag nanoparticle-decorated graphene oxide and carbon fiber on electrical actuation of polymeric shape memory nanocomposites

“…The utilization of electrically resistive Joule heating to drive SME is desirable and convenient to apply in a number of real-life applications, especially where direct heating is not easily achieved. A variety of conductive fillers from zero dimensional particles, one dimensional chains to two dimensional films, such as carbon nanotubes (CNTs) [22], carbon black [23], carbon nanofibers (CNFs) [24,25], magnetic particles [26], short carbon fibers [27,28], conductive alignment [29,30], CNF mat [31] and nanopaper [32] have been used in the SMP nanocomposites. These conductive fillers not only enable remote actuation of shape transitions but also enhance the thermal conductivity [33][34][35].…”

Shape Memory Polymer–Inorganic Hybrid Nanocomposites

“…In 2007, Miaudet et al demonstrated broad glass transition temperatures as a result of incorporation of CNT fillers [21]. Further, in 2010, Lu et al modified a styrene-based shape memory polymer resin from the Ohio-based Cornerstone Research Group with carbon black fillers and carbon fiber fillers [22]. Nji and Li developed both a three-dimensional (3D) woven fabric reinforced SMP composite based on organic materials for impact resistance [23,24] and an SMP composite based on biomimicry.…”

Electroactive shape-memory polymer nanocomposites incorporating carbon nanofiber paper

“…Current efforts to implement this technology use conducting SMP composites with carbon nanotubes [7], short carbon fibers (SCFs) [8,9,12], and metallic Ni powder [10,11]. The shape memory effect in these types of SMPs have been shown to depend on the filler content, and they exhibit good energy conversion efficiency and improved mechanical properties.…”

“…However, the actuation approach of shape recovery is seriously limited by traditional direct temperature heating procedures. Fortunately, many interesting and valuable studies have been done on the actuation of SMPs or SMP composites, for which shape recovery can not only be induced by external stimuli, such as heating, but can be manipulated by infrared light heating [5], laser light heating [6], electrical resistive heating [7][8][9][10][11][12][13], magnetic fields [14,15] or solvents [16][17][18].…”