• Applied Chemistry for Engineering
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• v.34 no.4
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• pp.347-356
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• 2023

Liquid crystal elastomer (LCE) fibers have been widely applied in various fields, such as soft robots and biomimetic actuators, in a one-dimensional form. LCEs possess the characteristics of both fluidity and solid order, as well as the elasticity of rubber, and exhibit stimulus-response based on these properties. In particular, by programming the responsiveness to various stimuli such as heat, light, electric fields, and magnetic fields in terms of shape-changing, various movements such as lifting, twisting, and rotating can be realized with high degrees of freedom. Therefore, LCE fibers have the potential for application in various fields such as artificial muscles, soft robots, wearable technologies, and sensing technologies. The research on liquid crystal elastomer fibers is evaluated to have high applicability in various fields in the Fourth Industrial Revolution as a smart material that can include various functionalities beyond simple fibers. In this review, we introduce the structure and basic characteristics of liquid crystal elastomer fibers, the latest research trends on orientation-based fabrication methods, and various applications such as artificial muscles, smart fabrics, and soft robots.

• Journal of the Korean Magnetic Resonance Society
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• v.5 no.1
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• pp.19-28
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• 2001

Miscibility and morphology in blends of bisphenol-A type polycarbonate and poly (ester-ether) elastomer with different compositions are studied by solid-state NMR spectroscopy. $^{13}$ C Solid-state NMR of CP/MAS/TOSS/DD, CP/MAS/DD, inversion recovery CP/MAS/DD, and 2D rotor driven spin diffusion techniques are used to identify the miscibility, morphology, and transesterification in blends. The blends of PC /BT elastomer with 15% to 42% of soft segment seem to be single phase miscible mixing and those of PC/PBT and PC/PBT elastomer with 62% of soft segment are cocontinuous two phase immiscible mixing. No significant transesterification reactions are observed in blends with different compositions.

• Proceedings of the Materials Research Society of Korea Conference
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• 2009.05a
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• pp.15.1-15.1
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• 2009

Nano transfer printing and micro contact printing is well known printing method based on soft lithography which uses conformal soft elastomer with designed surface relief structures. Here I introduce another class of novel 3D nanofabrication technique by using the same elastomer but in a different manner. The approach, which we refer to as proximity field nanopatterning, uses the surface-reliefed elastomers as phase masks to pattern thick layers of transparent, photosensitive materials. Aspects of the optics, the materials, and the physical chemistry associated with this method are outlined. A range of 3D structures illustrate its capabilities, and several application examples demonstrate possible areas of use in technologies ranging from microfluidics to photonic materials to density gradient structures for chemical release and high-energy density science.

• Fisheries and Aquatic Sciences
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• v.10 no.4
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• pp.226-229
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• 2007

Survival, tag retention and tag readability were compared among the control and three treatment groups of soft-shelled turtles, Pelodiscus sinensis Crother, 2000 (mean body $weight{\pm}SD$: $182.6{\pm}13.7\;g$), marked with visible implant fluorescent elastomer (VIFE) tags for 16 months. Mortality 4 to 16 months after tagging was attributed to collection and handling stress rather than to the tagging itself. Tags applied to the web surface between the fourth and fifth dactyl of the hindfoot appeared to have the highest retention rates, while adipose eyelid tagging had high tag readability but a high loss rate. We conclude that in soft-shelled turtles, the most suitable region for VIFE tagging is on the web surface between the fourth and fifth dactyls of the hindfoot.

• Proceedings of the Korean Aquaculture Society Conference
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• 2006.05a
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• pp.306-307
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• 2006

• Composites Research
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• v.26 no.5
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• pp.289-294
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• 2013

A thinner is used to improve the multi-walled carbon nano-tube (CNT) and carbon black (CB) dispersion in a polymer matrix and to make a soft electrode. The electrical and mechanical properties of the soft electrodes are investigated as functions of CNT, CB and thinner content. The optimal mixing condition for the electrode is thinner 80, CNT 3.5, CB 18 (phr) on the basis of matrix (KE-12). The specific resistance of that is 73 (${\Omega}{\cdot}cm$), and tensile strength, tensile modulus, and elongation of that is 0.45 MPa, 0.21 MPa, and 184%, respectively. Also, a simple structure of the actuator with an optimized electrode and elastomer is fabricated and its characteristic is evaluated. At the operating voltage 25 kV, the displacement of an elastomer KE-12 is 2.24 mm, and that of an elastomer KE-12 with thinner 50 (phr) is 4.05 mm. It shows a higher displacement compared to that of 3M 4910 which has similar modulus. The actuator made with elastomer and electrode of the same material (KE-12) may have advantages for fatigue life and application.

• Journal of Information Processing Systems
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• v.18 no.5
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• pp.688-700
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• 2022

A composite bionic soft gripper integrated with electromagnets and magneto-active elastomers is designed by combining the structure of the human hand and the snake's behavior of enhancing friction by actively adjusting the scales. A silicon-based polymer containing magnetized hard magnetic particles is proposed as a soft finger, and it can be reversibly bent by adjusting the magnetic field. Experiments show that the length, width, and height of rectangular soft fingers and the volume ratio of neodymium-iron-boron have different effects on bending angle. The flexible fingers with 20 vol% are the most efficient, which can bend to 90° when the magnetic field is 22 mT. The flexible gripper with four fingers can pick up 10.51 g of objects at the magnetic field of 105 mT. In addition, this composite bionic soft gripper has excellent magnetron performance, and it can change surface like snakes and operate like human hands. This research may help develop soft devices for magnetic field control and try to provide new solutions for soft grasping.

• Journal of the Semiconductor & Display Technology
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• v.5 no.4 s.17
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• pp.41-45
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• 2006

Micro vibration isolation, typically originated from ground, is always a prime concern for the nano-measurement instruments such as Atomic Force Microscopes. A four mount active vibration isolation system is proposed in this paper. Modeling and control of such a four mount system was analyzed. Combined active-passive isolation principle is used for vibration isolation by mounting the instrument on a passively damped isolation system made of Elastomer along with the active stage in parallel that consists of very soft actuation system, the Voice Coil Motor. The active stage works in combination with the passive stage for working as a very low frequency vibration attenuator.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.40 no.9
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• pp.815-820
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• 2016

An elastic polymer (e.g., PDMS) blended with EFG particles is a promising conductive composite for fabricating soft sensors that can detect an object's deformation up to or more than 50%. Here, we develop large-strain, sprayable soft sensors using a mixture of PDMS and EFG particles, which are used as a host elastomer and electrically conductive particles, respectively. A solution for a conductive composite mixture is prepared by the microwave-assisted graphite exfoliation, followed by ultrasonication-induced fragmentation of the exfoliated graphite and ultrasonic blending of PDMS and EFG. Using the prepared solutions for composite and pure PDMS, 1-, 2-, and 3-axis soft sensors are fabricated by airbrush stencil technique where composite mixture and pure PDMS are materials for sensing and insulating layers, respectively. We characterize the soft strain sensors after investigating the effect of PDMS/EFG wt% on mechanical compliance and electrical conductance of the conductive composite.

• Proceedings of the Korean Fiber Society Conference
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• 1998.04a
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• pp.1-4
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• 1998

Segmented Polyurethanes Elastomers are a class of polymers having interesting properties which arise from their unique phase-separated structures resulting from the thermodynamic incompatibility of the ingredients[1]. Segmented polyurethane Elastomer generally consists of a segment derived from a polymeric diol and a hard segment from a diisocyanate and a low molecular weight diol(chain extender).(omitted)