CNT-Br/PEDOT:PSS/PAAS three-network composite conductive hydrogel for human motion monitoring

AbstractFlexible sensors in wearable electronics have become increasingly multifunctional due to the development of materials synthesis and structure design. In particular, structural design can not only add capabilities to sensors fabricated from existing available and normal materials, but also offer opportunities for the fabrication of sensors with certain desired functions. Here, we designed a series of fiber-junction structure models, in which two fibers were simply hooked to each other to form a junction on a flexible printed circuit, for fabrication of directional bending sensors. The value and direction of bending angle are related to the change in electronic signal by a theoretical expression, allowing us to employ a simple and practicable method to use available conductive fiber materials to fabricate high-sensitivity, high-resolution and directional bending sensors. In addition, these models are generally applicable, which have broad combination with different conductive fiber, and corresponding bending sensors all possess capability of directional identification. Furthermore, the capability of identifying directional bending was demonstrated by human motion monitoring such as joint bending and muscle contraction.

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Multi-functional and water-resistant conductive silver nanoparticle-decorated cotton textiles with excellent joule heating performances and human motion monitoring

Cellulose ◽

10.1007/s10570-021-03955-y ◽

2021 ◽

Author(s):

Zengpei Guo ◽

Yilun Wang ◽

Jingjing Huang ◽

Shiyu Zhang ◽

Ruquan Zhang ◽

...

Keyword(s):

Joule Heating ◽

Silver Nanoparticle ◽

Human Motion ◽

Cotton Textiles ◽

Human Motion Monitoring

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A Centimeter Resolution, 10 m Range CMOS Impulse Radio Radar for Human Motion Monitoring

IEEE Journal of Solid-State Circuits ◽

10.1109/jssc.2014.2310746 ◽

2014 ◽

Vol 49 (5) ◽

pp. 1125-1134 ◽

Cited By ~ 13

Author(s):

Piljae Park ◽

Sungdo Kim ◽

Sungchul Woo ◽

Cheonsoo Kim

Keyword(s):

Impulse Radio ◽

Human Motion ◽

Human Motion Monitoring

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A highly stretchable strain sensor based on electrospun carbon nanofibers for human motion monitoring

RSC Advances ◽

10.1039/c6ra16236c ◽

2016 ◽

Vol 6 (82) ◽

pp. 79114-79120 ◽

Cited By ~ 41

Author(s):

Yichun Ding ◽

Jack Yang ◽

Charles R. Tolle ◽

Zhengtao Zhu

Keyword(s):

Carbon Nanofibers ◽

Strain Sensor ◽

Human Motion ◽

Sensitive Strain ◽

Free Standing ◽

Highly Stretchable ◽

Human Motion Monitoring

A highly stretchable and sensitive strain sensor assembled by embedding a free-standing electrospun carbon nanofibers (CNFs) mat in a polyurethane (PU) matrix shows a fast, stable, and reproducible response to strain up to 300%.

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High strength and conductive hydrogel with fully interpenetrated structure from alginate and acrylamide

e-Polymers ◽

10.1515/epoly-2021-0043 ◽

2021 ◽

Vol 21 (1) ◽

pp. 391-397

Author(s):

Tao Liu ◽

Ripeng Zhang ◽

Jianzhi Liu ◽

Ling Zhao ◽

Yueqin Yu

Keyword(s):

Mechanical Performance ◽

Three Dimensional ◽

High Strength ◽

Extreme Environment ◽

Natural Polymers ◽

Conductive Hydrogel ◽

Wide Range ◽

Interpenetrated Structure ◽

Conductive Hydrogels ◽

Conductive Properties

Abstract Highly stretched and conductive hydrogels, especially synthetized from natural polymers, are beneficial for highly stretched electronic equipment which is applied in extreme environment. We designed and prepared robust and tough alginate hydrogels (GMA-SA-PAM) using the ingenious strategy of fully interpenetrating cross-linking, in which the glycidyl methacrylate (GMA) was used to modify sodium alginate (SA) and then copolymerized with acrylamide (AM) and methylenebisacrylamide (BIS) as cross-linkers. The complete cross-linked structures can averagely dissipate energy and the polymer structures can maintain hydrogels that are three-dimensional to greatly improve the mechanical performance of hydrogels. The GMA-SA-PAM hydrogels display ultra-stretchable (strain up to ∼407% of tensile strain) and highly compressible (∼57% of compression strain) properties. In addition, soaking the GMA-SA-PAM hydrogel in 5 wt% NaCl solution also endows the conductivity of the hydrogel (this hydrogel was named as GSP-Na) with excellent conductive properties (5.26 S m−1). The GSP-Na hydrogel with high stability, durability, as well as wide range extent sensor is also demonstrated by researching the electrochemical signals and showing the potential for applications in wearable and quickly responded electronics.

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Stimuli-responsive conductive hydrogels: design, property and applications

Materials Chemistry Frontiers ◽

10.1039/d0qm00868k ◽

2021 ◽

Author(s):

Zexing Deng ◽

Rui Yu ◽

Baolin Guo

Keyword(s):

Conductive Polymers ◽

Research Field ◽

Stimuli Responsive ◽

Conductive Hydrogel ◽

Design Property ◽

Conductive Hydrogels

Stimuli-responsive conductive hydrogel has been emerged as a new surging concept in hydrogel research field due to its combined advantages of stimuli-responsivity and conductivity from conductive polymers (such as polyaniline,...

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Robust Conductive Hydrogels with Ultrafast Self-Recovery and Nearly Zero Response Hysteresis for Epidermal Sensors

Nanomaterials ◽

10.3390/nano11071854 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1854

Author(s):

Xiuru Xu ◽

Chubin He ◽

Feng Luo ◽

Hao Wang ◽

Zhengchun Peng

Keyword(s):

Guar Gum ◽

Strain Range ◽

Sio2 Nanoparticles ◽

Fast Response ◽

Gauge Factor ◽

Practical Applications ◽

Hydroxypropyl Guar ◽

Stable Chemical ◽

Conductive Hydrogel ◽

Conductive Hydrogels

Robust conductive hydrogels are in great demand for the practical applications of smart soft robots, epidermal electronics, and human–machine interactions. We successfully prepared nanoparticles enhanced polyacrylamide/hydroxypropyl guar gum/acryloyl-grafted chitosan quaternary ammonium salt/calcium ions/SiO2 nanoparticles (PHC/Ca2+/SiO2 NPs) conductive hydrogels. Owing to the stable chemical and physical hybrid crosslinking networks and reversible non-covalent interactions, the PHC/Ca2+/SiO2 NPs conductive hydrogel showed good conductivity (~3.39 S/m), excellent toughness (6.71 MJ/m3), high stretchability (2256%), fast self-recovery (80% within 10 s, and 100% within 30 s), and good fatigue resistance. The maximum gauge factor as high as 66.99 was obtained, with a wide detectable strain range (from 0.25% to 500% strain), the fast response (25.00 ms) and recovery time (86.12 ms), excellent negligible response hysteresis, and good response stability. The applications of monitoring the human’s body movements were demonstrated, such as wrist bending and pulse tracking.

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Preparation of Carbon Fiber-Polyacrylamide Composite Hydrogel Based on Surface Electric-Initiated Polymerization

Journal of Nanoelectronics and Optoelectronics ◽

10.1166/jno.2021.3028 ◽

2021 ◽

Vol 16 (6) ◽

pp. 861-868

Author(s):

Mengge Lv ◽

Xinfang Wei ◽

Liwen Peng

Keyword(s):

Composite Material ◽

Carbon Fiber ◽

Electrochemical Polymerization ◽

Crosslinking Agent ◽

Monomer Concentration ◽

Conductive Filler ◽

Composite Effect ◽

Conductive Hydrogel ◽

Graft Modification ◽

Conductive Hydrogels

Conductive hydrogels have shown excellent application prospects in the fields of bioelectronics, tissue engineering, wearable devices, etc. However, its poor compatibility at the organic-inorganic interface affects its mechanical strength and limits its wide application. We prepared carbon fiber-polyacrylamide organic-inorganic composite material by electrochemical polymerization using N,N-methylenebisacrylamide as the crosslinking agent, acrylamide as the monomer, and carbon fiber as the conductive filler. It forms a conductive hydrogel after absorbing water. The effects of monomer concentration, reaction time, and current on the composite material were investigated in this article. The experimental results show that a large number of irregular bumps are produced on the surface of carbon fiber, and various characterization tests show that it is polyacrylamide (PAM) that successfully attached to carbon fiber. Under the same electrochemical polymerization time, the current density and monomer concentration have little effect on the molecular weight which mainly concentrated around 6.2 × 105. The graft modification of PAM reduces the defects on the surface of the carbon fiber, and the composite effect is good.

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