A Thermally-Electrically Double-Responsive Polycaprolactone - Thermoplastic polyurethane / Multi-walled Carbon Nanotubes Fiber Assisted with Highly Effective Shape Memory and Strain Sensing Performance

In this work, a fast water-responsive shape memory hybrid polymer based on thermoplastic polyurethane (TPU) was prepared by crosslinking with hydroxyethyl cotton cellulose nanofibers (CNF-C) and multi-walled carbon nanotubes (CNTs). The effect of CNTs content on the electrical conductivity of TPU/CNF-C/CNTs nanocomposite was investigated for the feasibility of being a strain sensor. In order to know its durability, the mechanical and water-responsive shape memory effects were studied comprehensively. The results indicated good mechanical properties and sensing performance for the TPU matrix fully crosslinked with CNF-C and CNTs. The water-induced shape fixity ratio (Rf) and shape recovery ratio (Rr) were 49.65% and 76.64%, respectively, indicating that the deformed composite was able to recover its original shape under a stimulus. The TPU/CNF-C/CNTs samples under their fixed and recovered shapes were tested to investigate their sensing properties, such as periodicity, frequency, and repeatability of the sensor spline under different loadings. Results indicated that the hybrid composite can sense large strains accurately for more than 103 times and water-induced shape recovery can to some extent maintain the sensing accuracy after material fatigue. With such good properties, we envisage that this kind of composite may play a significant role in developing new generations of water-responsive sensors or actuators.

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Preparation of modified multi‐walled carbon nanotubes as a reinforcement for epoxy shape‐memory polymer composites

Polymers for Advanced Technologies ◽

10.1002/pat.5061 ◽

2020 ◽

Vol 32 (1) ◽

pp. 67-75

Author(s):

Yanling Wang ◽

Longhao Tang ◽

Yongfei Li ◽

Qiang Li ◽

Baojun Bai

Keyword(s):

Carbon Nanotubes ◽

Shape Memory ◽

Polymer Composites ◽

Shape Memory Polymer ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes

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Compression Moulding of Thermoplastic Nanocomposites Filled with MWCNT

Polymers and Polymer Composites ◽

10.1177/096739111702500806 ◽

2017 ◽

Vol 25 (8) ◽

pp. 611-620 ◽

Cited By ~ 1

Author(s):

Fabrizio Quadrini ◽

Denise Bellisario ◽

Loredana Santo ◽

Felicia Stan ◽

Fetecau Catalin

Keyword(s):

Carbon Nanotubes ◽

Differential Scanning Calorimetry ◽

Filler Content ◽

Thermoplastic Polyurethane ◽

Mechanical Tests ◽

Compression Moulding ◽

Scanning Calorimetry ◽

Melt Mixing ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes

Multi-walled carbon-nanotubes (MWCNTs) were melt-mixed with three different thermoplastic matrices (polypropylene, PP, polycarbonate, PC, and thermoplastic polyurethane, TPU) to produce nanocomposites with three different filler contents (1, 3, and 5 wt.%). Initial nanocomposite blends (in the shape of pellets) were tested under differential scanning calorimetry to evaluate the effect of the melt mixing stage. Nanocomposite samples were produced by compression moulding in a laboratory-scale system, and were tested with quasi-static (bending, indentation), and dynamic mechanical tests as well as with friction tests. The results showed the effect of the filler content on the mechanical and functional properties of the nanocomposites. Compression moulding appeared to be a valuable solution to manufacture thermoplastic nanocomposites when injection moulding leads to loss of performance. MWCNT-filled thermoplastics could be used also for structural and functional uses despite, the present predominance of electrical applications.

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