Introduction to Ionic Polymers, Ionic Gels and Stimuli-Responsive Materials and Artificial Muscles

Biological muscles exhibit a high level of integration, in which actuators, sensors and transmission elements can be included in one component. Artificial muscles or actuators refer to intelligent stimuli-responsive materials that could reversibly deform with the trigger of various external stimuli. These materials, which have attracted tremendous attention, produce natural muscle-like actuation performance and show promising applications in robotics. After an introduction of various actuator technologies that contribute to robotic applications, a comparative analysis of the main actuation parameter is provided. The comprehensive comparisons of each kind of artificial muscle are summarised, and the promising properties that are required in robotics are presented, which highlight the development of their actuation performances and the challenges that limit their further employments. Future developmental prospects and perspectives of artificial actuators are discussed.

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Helical Actuators Inspired by Chiral Seedpod Opening and Tendril Coiling

10.20944/preprints201807.0094.v1 ◽

2018 ◽

Author(s):

Guangchao Wan ◽

Congran Jin ◽

Ian Trase ◽

Shan Zhao ◽

Zi Chen

Keyword(s):

Multiwall Carbon Nanotubes ◽

Artificial Muscles ◽

Stimuli Responsive ◽

Helical Structures ◽

Responsive Materials ◽

Intelligent Machines ◽

Essential Components ◽

Potential Applications ◽

External Stimuli ◽

Tendril Coiling

Actuators are essential components for intelligent machines that can fulfill certain tasks in response to environmental stimuli. In recent years, actuators that can transform from a 2D ribbon shape to a 3D helical configuration under certain external stimuli have attracted significant attention due to the potential applications of the targeted helical structures in springs, propulsion generation, and artificial muscles. Inspired by the chiral opening of Bauhinia variegate‘s seedpods and the coiling of the Towel Gourd tendril with perversions, researchers have made significant breakthroughs in synthesizing state-of-the-art actuators capable of mimicking helical transformations. In this review, we give a brief overview of the shape evolution mechanisms of these two plant structures and then review recent progress in the fabrication of biomimetic helical actuators. These structures are categorized by the stimuli-responsive materials involved, including hydrogels, liquid crystal networks/elastomers, shape memory polymers, and multiwall carbon nanotubes. By providing this survey on important recent advances along with our perspectives, we hope to solicit new inspirations and insights on the development and fabrication of smart actuators, as well as the future development of interdisciplinary research at the interface of physics, engineering, and biology.

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Smart Polymers and their Applications: A Review

International Journal of Current Pharmaceutical Review and Research ◽

10.25258/ijcprr.v8i03.9220 ◽

2017 ◽

Vol 8 (03) ◽

Author(s):

Gore S. A. ◽

Gholve S. B. ◽

Savalsure S. M. ◽

Ghodake K. B. ◽

Bhusnure O. G. ◽

...

Keyword(s):

Oil Recovery ◽

Water Soluble ◽

Solution Temperature ◽

Smart Polymers ◽

Stimuli Responsive ◽

Responsive Materials ◽

Water Soluble Polymers ◽

Commercial Applications ◽

Stimuli Sensitive ◽

External Stimuli

Smart polymers are materials that respond to small external stimuli. These are also referred as stimuli responsive materials or intelligent materials. Smart polymers that can exhibit stimuli-sensitive properties are becoming important in many commercial applications. These polymers can change shape, strength and pore size based on external factors such as temperature, pH and stress. The stimuli include salt, UV irradiation, temperature, pH, magnetic or electric field, ionic factors etc. Smart polymers are very promising applicants in drug delivery, tissue engineering, cell culture, gene carriers, textile engineering, oil recovery, radioactive wastage and protein purification. The study is focused on the entire features of smart polymers and their most recent and relevant applications. Water soluble polymers with tunable lower critical solution temperature (LCST) are of increasing interest for biological applications such as cell patterning, smart drug release, DNA sequencing etc.

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Sensitive Mechanocontrolled Luminescence in Cross-Linked Polymer Films

10.26434/chemrxiv.9943943.v1 ◽

2019 ◽

Author(s):

Ayumu Karimata ◽

Pradnya Patil ◽

Eugene Khaskin ◽

Sébastien Lapointe ◽

robert fayzullin ◽

...

Keyword(s):

Mechanical Stress ◽

Polymer Films ◽

Soft Matter ◽

Small Strain ◽

Visual Methods ◽

Photoluminescence Intensity ◽

Stimuli Responsive ◽

Responsive Materials ◽

Highly Sensitive ◽

Mechanical Stretching

Direct translation of mechanical force into changes in chemical behavior on a molecular level has important implication not only for the fundamental understanding of mechanochemical processes, but also for the development of new stimuli-responsive materials. In particular, detection of mechanical stress in polymers via non-destructive methods is important in order to prevent material failure and to study the mechanical properties of soft matter. Herein, we report that highly sensitive changes in photoluminescence intensity can be observed in response to the mechanical stretching of cross-linked polymer films when using stable, (pyridinophane)Cu-based dynamic mechanophores. Upon stretching, the luminescence intensity increases in a fast and reversible manner even at small strain (< 50%) and applied stress (< 0.1 MPa) values. Such sensitivity is unprecedented when compared to previously reported systems based on organic mechanophores. The system also allows for the detection of weak mechanical stress by spectroscopic measurements or by direct visual methods.<br>

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Redox-State Dependent Spectroscopic Properties of Porous Organic Polymers Containing Furan, Thiophene, and Selenophene

Australian Journal of Chemistry ◽

10.1071/ch17335 ◽

2017 ◽

Vol 70 (11) ◽

pp. 1227 ◽

Cited By ~ 2

Author(s):

Carol Hua ◽

Stone Woo ◽

Aditya Rawal ◽

Floriana Tuna ◽

James M. Hook ◽

...

Keyword(s):

Solid State ◽

Redox State ◽

Spectroscopic Properties ◽

Structural Features ◽

Organic Polymers ◽

Stimuli Responsive ◽

Porous Organic Polymers ◽

Paramagnetic Resonance ◽

Responsive Materials ◽

State Dependent

A series of electroactive triarylamine porous organic polymers (POPs) with furan, thiophene, and selenophene (POP-O, POP-S, and POP-Se) linkers have been synthesised and their electronic and spectroscopic properties investigated as a function of redox state. Solid state NMR provided insight into the structural features of the POPs, while in situ solid state Vis-NIR and electron paramagnetic resonance spectroelectrochemistry showed that the distinct redox states in POP-S could be reversibly accessed. The development of redox-active porous organic polymers with heterocyclic linkers affords their potential application as stimuli responsive materials in gas storage, catalysis, and as electrochromic materials.

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Shape memory polymer network with thermally distinct elasticity and plasticity

Science Advances ◽

10.1126/sciadv.1501297 ◽

2016 ◽

Vol 2 (1) ◽

pp. e1501297 ◽

Cited By ~ 232

Author(s):

Qian Zhao ◽

Weike Zou ◽

Yingwu Luo ◽

Tao Xie

Keyword(s):

Shape Memory ◽

Molecular Design ◽

Shape Change ◽

Shape Memory Polymer ◽

Polymer Network ◽

Stimuli Responsive ◽

Responsive Materials ◽

Device Applications ◽

Temperature Ranges ◽

Rational Molecular Design

Stimuli-responsive materials with sophisticated yet controllable shape-changing behaviors are highly desirable for real-world device applications. Among various shape-changing materials, the elastic nature of shape memory polymers allows fixation of temporary shapes that can recover on demand, whereas polymers with exchangeable bonds can undergo permanent shape change via plasticity. We integrate the elasticity and plasticity into a single polymer network. Rational molecular design allows these two opposite behaviors to be realized at different temperature ranges without any overlap. By exploring the cumulative nature of the plasticity, we demonstrate easy manipulation of highly complex shapes that is otherwise extremely challenging. The dynamic shape-changing behavior paves a new way for fabricating geometrically complex multifunctional devices.

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