Light-fuelled freestyle self-oscillators

Abstract Self-oscillation is a phenomenon where an object sustains periodic motion upon non-periodic stimulus. It occurs commonly in nature, a few examples being heartbeat, sea waves and fluttering of leaves. Stimuli-responsive materials allow creating synthetic self-oscillators fuelled by different forms of energy, e.g. heat, light and chemicals, showing great potential for applications in power generation, autonomous mass transport, and self-propelled micro-robotics. However, most of the self-oscillators are based on bending deformation, thereby limiting their possibilities of being implemented in practical applications. Here, we report light-fuelled self-oscillators based on liquid crystal network actuators that can exhibit three basic oscillation modes: bending, twisting and contraction-expansion. We show that a time delay in material response dictates the self-oscillation dynamics, and realize a freestyle self-oscillator that combines numerous oscillation modes simultaneously by adjusting the excitation beam position. The results provide new insights into understanding of self-oscillation phenomenon and offer new designs for future self-propelling micro-robots.

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4D printing technology, modern era: A short review

International Journal of Energy Technology ◽

10.32438//ijet.203015 ◽

2020 ◽

pp. 92-111

Author(s):

Khodadad Mostakim ◽

Nahid Imtiaz Masuk ◽

Md. Rakib Hasan ◽

Md. Shafikul Islam

Keyword(s):

Smart Materials ◽

Computer Aided Design ◽

Short Review ◽

Stimuli Responsive ◽

4D Printing ◽

Space Applications ◽

Printing Technology ◽

Practical Applications ◽

Biomedical Technologies ◽

Novel Material

The advancement in 3D printing has led to the rapid growth of 4D printing technology. Adding time, as the fourth dimension, this technology ushered the potential of a massive evolution in fields of biomedical technologies, space applications, deployable structures, manufacturing industries, and so forth. This technology performs ingenious design, using smart materials to create advanced forms of the 3-D printed specimen. Improvements in Computer-aided design, additive manufacturing process, and material science engineering have ultimately favored the growth of 4-D printing innovation and revealed an effective method to gather complex 3-D structures. Contrast to all these developments, novel material is still a challenging sector. However, this short review illustrates the basic of 4D printing, summarizes the stimuli responsive materials properties, which have prominent role in the field of 4D technology. In addition, the practical applications are depicted and the potential prospect of this technology is put forward.

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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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Ferro-self-assembly: magnetic and electrochemical adaptation of a multiresponsive zwitterionic metalloamphiphile showing a shape-hysteresis effect

Chemical Science ◽

10.1039/d0sc05249c ◽

2021 ◽

Vol 12 (1) ◽

pp. 270-281

Author(s):

Stefan Bitter ◽

Moritz Schlötter ◽

Markus Schilling ◽

Marina Krumova ◽

Sebastian Polarz ◽

...

Keyword(s):

Magnetic Field ◽

Light Scattering ◽

Dynamic Light Scattering ◽

Real Time ◽

Self Assembly ◽

Hysteresis Effect ◽

The Self ◽

Self Organization ◽

Stimuli Responsive ◽

Optical Birefringence

The self-organization properties of a stimuli responsive amphiphile can be altered by subjecting the paramagnetic oxidized form to a magnetic field of 0.8 T and monitored in real time by coupling optical birefringence with dynamic light scattering.

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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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