Application Of Smart Materials Research Articles

Parallel Manipulation and Flexible Assembly of Micro-Spiral via Optoelectronic Tweezers.

Micro-spiral has a wide range of applications in smart materials, such as drug delivery, deformable materials, and micro-scale electronic devices by utilizing the manipulation of electric fields, magnetic fields, and flow fields. However, it is incredibly challenging to achieve a massively parallel manipulation of the micro-spiral to form a particular microstructure in these conventional methods. Here, a simple method is reported for assembling micro-spirals into various microstructures via optoelectronic tweezers (OETs), which can accurately manipulate the micro-/bio-particles by projecting light patterns. The manipulation force of micro-spiral is analyzed and simulated first by the finite element simulation. When the micro-spiral lies at the bottom of the microfluidic chip, it can be translated or rotated toward the target position by applying control forces simultaneously at multiple locations on the long axis of the micro-spiral. Through the OET manipulation, the length of the micro-spiral chain can reach 806.45 μm. Moreover, the different parallel manipulation modes are achieved by utilizing multiple light spots. The results show that the micro-spirulina can be manipulated by a real-time local light pattern and be flexibly assembled into design microstructures by OETs, such as a T-shape circuit, link lever, and micro-coil pairs of devices. This assembly method using OETs has promising potential in fabricating innovative materials and microdevices for practical engineering applications.

Synergistic Effect of Amino-Functionalized Multiwalled Carbon Nanotube Incorporated Polyurethane Nanocomposites for High-Performance Smart Materials Applications

Synergistic Effect of Amino-Functionalized Multiwalled Carbon Nanotube Incorporated Polyurethane Nanocomposites for High-Performance Smart Materials Applications

Random forest-based physical activities recognition by using wearable sensors

Physical activity recognition (PAR) is a topic worthy of attention. In order to improve the practicality of wearable sensors for recognition, in this study, we propose an approach to create a classifier of PAR based on the collected data. At first, we discuss how features extracted from the accelerometer and gyroscope contribute to distinguish different activities, including walking, walking upstairs, walking downstairs, sitting, standing, laying, and also provide an analytical method employed for this purpose. Then, a supervised machine learning method, random forest algorithm, is adopted to create a classifier to recognize physical activities based on the extracted features. Lastly, the performances of the constructed classifier are evaluated and compared with other methods. The performance evaluation shows the classifier trained by random forest algorithm are better than other algorithms, and its overall recognition rate reaches 93.75%. In addition, our approach also has strong potential for applications in smart textiles.

Progress in the development of photoactivated materials for smart and active food packaging: Photoluminescence and photocatalysis approaches

Damage, contamination, or waste of foods during their storage, transportation and sale are serious challenges to global food security. Innovative packaging materials are being developed to tackle these problems. Active packaging materials are being developed to extend the shelf life of foods by including antimicrobials or antioxidants. Smart packaging materials are being developed to monitor the quality, maturity, and safety of foods in real time. Photoactivated materials capable of photoluminescence or photocatalysis are being utilized to fabricate these smart and active food packaging. Photoluminescence-based sensors can be used to monitor environmental changes in food packaging, such as gas leakage, freshness, and the presence of specific microorganisms. Photocatalysis-based devices can be used as color indicators, as well as to inhibit a broad spectrum of microbes and for gas removal. This review summarizes the latest research on the application of photoactivated materials in smart and active food packaging. The preparation, operating principles, applications of photoactivated materials in food packaging materials are discussed, as well as their potential advantages and disadvantages. The knowledge presented may stimulate more research on the development and application of innovative smart and active food packaging materials in the food industry.

Investigation of Resilience of Eccentrically Braced Frames Equipped with Shape Memory Alloys

Abstract Nowadays, the use of smart materials in structures is a major concern to structural engineers. The act of benefiting from numerous advantages of these materials is the main objective of researches and studies focused on seismic and structural engineering. In the present study, in addition to the development of finite element models of several steel frames using ABAQUS software, the effect of shape memory alloys (SMAs) on superelastic behavior and the various types of eccentric braces will be checked. Moreover, it was observed that the use of SMAs within various types of bracing systems of steel frames leads to a decrease in the reduction factor of the frames. Also, the eccentric bracing in which SMAs are utilized in the middle of bracing led to the highest effect on reduction of lateral drift of the frames and decrease of reduction factor. The obtained results indicated that the application of smart materials led to increasing of strain energy and base shear of the first plastic hinge, which is followed by a decrease in the reduction factor of the frame.

Bamboo-inspired cell-scale assembly for energy device applications

Rapid advances in flexible and wearable smart textiles demand low-cost, high-energy/power-density fiber-shaped supercapacitors (FSCs). The performance of FSCs is determined by the fabrication and assembly of fiber-shaped electrodes (FSEs), where an active charge-storage material is always clad around flexible charge transmission current collectors. Inspired by the tissue structure of natural bamboo, wherein parenchyma cells (PCs) that store nutrients are clad around bamboo fibers (BFs), we propose a strategy for converting bamboo cells into FSEs using conductive BFs and activated PCs as current collectors and active materials, respectively. The assembled electrode has a high specific capacitance of 1454 mF cm−2 at 0.64 mA cm−2. A solid-state FSC with a pair of bamboo-structured electrodes exhibited a substantially high energy density. Its mechanical flexibility enabled the knitting of wearable wristbands to drive ultra-small voltmeter indicators. This lightweight, low cost, and high-energy-density bamboo-structured FSC could enable numerous smart textile applications.

Smart Materials- Types & Applications

Abstract: Smart Materials are also known as advanced materials or intelligent materials or responsive materials. These materials can be defined as advanced materials that can respond smartly to environmental changes. The general feature of all smart materials is the fact that one or more properties might be significantly altered under controlled conditions by external stimuli such as stress, moisture, electric fields, magnetic fields, light, temperature etc.. This study focuses on Smart Materials types and applications in various fields. Keywords: Actuator, Piezoelectric, Sensors, Shape Memory Alloys, Smart Materials.

5D Printing : A future beyond the scope of 4D printing with application of smart materials

The aim of the study is to present the technique currently used in 3D and 4D printing and add a 5D Printing dimension in the existing printing technique. This study illustrates the ways in which the fifth dimension could be implemented in present printing techniques in various fields. The methodology of study was a combination of review of research articles in 3D printing process, discussion with experts in 3D printing industry, field study to see the industrial applications of 3D printers, investigation of various materials used for 3D printing and documenting the various make-believe ideas of authors which can be implemented. The result of this investigation unearths some materials which have the ability to change shape during printing process, where the shape of an object changes when exposed to different environments. These materials can be termed as smart materials. These materials have helped in the evolution of 4D Printers. The industrial applications of 4D printing make clear that the needs of the future can be catered by the 4D Printed objects by utilizing smart and intelligent materials. The study concludes explaining that morphing is the main characteristics added to a 3D printed object giving rise to 4D printers and further if these shape changing characteristics of 4D printed objects can be controlled either by some sensors or actuators, then it can give rise to 5D printers.

Significant applications of smart materials and Internet of Things (IoT) in the automotive industry

This paper discusses the significant applications of Smart materials and the Internet of Things (IoT) in the automobile industry. These are the two technologies most tech companies are working on right now. These both have resulted in the game-changing technologies of this era. Firstly, the various IoT solutions from companies like Airbus, Boeing, Amazon, John Deere, Bosch, Shell, and many more are discussed. Technologies like Advanced Driver-Assistance Systems, Connected Cars, V2V, V2I, V2P, V2X, and CV2X have also been discussed. Then we discussed the ongoing research in developing nations like India. We have discussed collaborations by different companies like Robert Bosch Engineering India Ltd., Renault Nissan Technical Center, Mercedes Benz Research and Development India, and Tata Elxsi. Then we talked about other properties smart materials possess (like transiency, immediacy and self-actuation, selectivity, self-diagnostic, and self-healing). Finally, various ongoing projects and inventions in smart materials by General Motors, Chevrolet Corvette, Hyundai Motor Group, KIA Corporation, and Lamborghini (Sián FKP 37 and Roadster) are discussed.

Tunable Circularly Polarized Luminescence of Excited‐State‐Proton‐Transfer‐Based Chiral Guanidine

Circularly polarized luminescence (CPL) of chiral materials responsive to external stimuli has drawn widespread attention due to their important applications in smart photonic materials. Here, a CPL‐active chiral emitter derived from guanidine‐substituted 1,8‐naphthalimide (R/S‐1) is reported, which could emit tunable circularly polarized light through regulating the situation of protonation/deprotonation in aqueous, as well as the solvent polarity. Tunable fluorescence emission from the protonated compound can be observed, which is contributed to excited‐state proton transfer of guanidine moiety, as well as the intramolecular charge transfer of naphthalimide group. Subsequently, color‐tunable CPL is obtained, enabling a single‐molecule‐white‐color circularly polarized light emission. Additionally, by introducing R/S‐1 into chiral nematic liquid crystal film, CPL emission is adjusted by exposing to acid/alkaline environment, which can be directly distinguished by naked eyes due to the extremely large dissymmetry factor (|glum| = 1.1). This work opens new venues for photonic applications of CPL active materials.

Plant-Based Structures as an Opportunity to Engineer Optical Functions in Next-Generation Light Management.

This review addresses the reconstruction of structural plant components (cellulose, lignin, and hemicelluloses) into materials displaying advanced optical properties. The strategies to isolate the main building blocks are discussed, and the effects of fibrillation, fibril alignment, densification, self-assembly, surface-patterning, and compositing are presented considering their role in engineering optical performance. Then, key elements that enable lignocellulosic to be translated into materials that present optical functionality, such as transparency, haze, reflectance, UV-blocking, luminescence, and structural colors, are described. Mapping the optical landscape that is accessible from lignocellulosics is shown as an essential step toward their utilization in smart devices. Advanced materials built from sustainable resources, including those obtained from industrial or agricultural side streams, demonstrate enormous promise in optoelectronics due to their potentially lower cost, while meeting or even exceeding current demands in performance. The requirements are summarized for the production and application of plant-based optically functional materials in different smart material applications and the review is concluded with a perspective about this active field of knowledge.

Photocatalytic self-cleaning and antibacterial activity of cotton fabric coated with polyaniline/carbon nitride composite for smart textile application

We have demonstrated the efficacy of a carbon nitride/polyaniline coated cotton fabric, as a smart self-cleaning material. The preparation of carbon nitride (CN) was carried out by thermal polymerization method and polyaniline (PANI) by chemical polymerization technique. The carbon nitride blended conducting polyaniline composite was coated over cotton fabric by using pad dry cure method. The carbon nitride polyaniline composite coated cotton fabrics show improved photocatalytic decomposition efficiency of 90% toward Rhodamine-B dye. The enhanced photocatalytic self-cleaning properties were achieved by using different colored dye stains under simulated solar light irradiation. The carbon nitride polyaniline composite has also shown good antimicrobial activity against gram negative bacteria.

Alginate-Based Smart Materials and Their Application: Recent Advances and Perspectives.

Nature produces materials using available molecular building blocks following a bottom-up approach. These materials are formed with great precision and flexibility in a controlled manner. This approach offers the inspiration for manufacturing new artificial materials and devices. Synthetic artificial materials can find many important applications ranging from personalized therapeutics to solutions for environmental problems. Among these materials, responsive synthetic materials are capable of changing their structure and/or properties in response to external stimuli, and hence are termed "smart" materials. Herein, this review focuses on alginate-based smart materials and their stimuli-responsive preparation, fragmentation, and applications in diverse fields from drug delivery and tissue engineering to water purification and environmental remediation. In the first part of this report, we review stimuli-induced preparation of alginate-based materials. Stimuli-triggered decomposition of alginate materials in a controlled fashion is documented in the second part, followed by the application of smart alginate materials in diverse fields. Because of their biocompatibility, easy accessibility, and simple techniques of material formation, alginates can provide solutions for several present and future problems of humankind. However, new research is needed for novel alginate-based materials with new functionalities and well-defined properties for targeted applications.

Asymmetric chiral disazo dopants with high anisotropy for versatile modulation of liquid crystal optics

As key elements, anisotropic chiral dopants determine the helical twisting power (HTP) of doped cholesteric liquid crystal (CLC) system by the host–guest interaction. To reveal the intrinsic structure–function relationship, we developed 3 novel asymmetric and photo-responsive chiral derivatives bearing axial chiral binaphthol moiety and disazo chromophore. They exhibited reversible photoisomerization, and rapidly induced helical degeneration of the doped CLC mixture under UV irradiation. Furthermore, highly asymmetric (R)-2′-hydroxy-[1,1′-binaphthalen]-2-yl 3,5-bis((E)-(4-butoxyphenyl)diazenyl)benzoate (molar absorption coefficient: 28,090 L⋅mol−1⋅cm−1; half-life period: 10.28 h; HTP: −34 um−1 in E7) was adopted to construct the CLC film with excellent NIR-reflection adjusted by light, heat, and electric field. It is a promising photoswitch agent for application in advanced smart materials and optical devices.

From Mesoscopic Functionalization of Silk Fibroin to Smart Fiber Devices for Textile Electronics and Photonics.

Bombyx mori silk fibers exhibit significant potential for applications in smart textiles, such as fiber sensors, fiber actuators, optical fibers, and energy harvester. Silk fibroin (SF) from B. mori silkworm fibers can be reconstructed/functionalized at the mesoscopic scale during refolding from the solution state into fibers. This facilitates the mesoscopic functionalization by engaging functional seeds in the refolding of unfolded SF molecules. In particular, SF solutions can be self‐assembled into regenerated fiber devices by artificial spinning technologies, such as wet spinning, dry spinning, microfluidic spinning, electrospinning, and direct writing. Meso‐functionalization manipulates the SF property from the mesoscopic scale, transforming the original silk fibers into smart fiber devices with smart functionalities, such as sensors, actuators, optical fibers, luminous fibers, and energy harvesters. In this review, the progress of mesoscopic structural construction from SF materials to fiber electronics/photonics is comprehensively summarized, along with the spinning technologies and fiber structure characterization methods. The applications, prospects, and challenges of smart silk fibers in textile devices for wearable personalized healthcare, self‐propelled exoskeletons, optical and luminous fibers, and sustainable energy harvesters are also discussed.

Application of Smart Materials in the Actuation System of a Gas Injector.

This paper presents the results of research related to the selection of materials for passive and active components of a three-layer piezoelectric cantilever converter. The transducer is intended for use in a low-pressure gas-phase injector executive system. To ensure the functionality of the injector, its flow characteristics and the effective range of valve opening had to be determined. Therefore, a spatial model of the complete injector was developed, and the necessary flow analyses were performed using computational fluid dynamics (CFD) in Ansys Fluent environment. The opening and closing of the injector valve are controlled by a piezoelectric transducer. Thus, its static electromechanical characteristics were found in analytical form. On this basis, the energy demand of the converter, required to obtain the desired valve opening, was determined. Assuming a constant transducer geometry, 40 variants of material combinations were considered. In the performed analyses, it was assumed that the passive elements of the actuator are made of typical materials used in micro-electromechanical systems (MEMSs) (copper, nickel, silicon alloys and aluminum alloys). As for the active components of the converter, it was assumed that they could be made of polymeric or ceramic piezoelectric materials. On the basis of the performed tests, it was found that the energy demand is most influenced by the relative stiffness of the transducer materials (Young’s modulus ratio) and the piezoelectric constant of the active component (d31). Moreover, it was found that among the tested material combinations, the transducer made of silicon oxide and PTZ5H (soft piezoelectric ceramics) had the lowest energy consumption.

Preparation of self-healing shape memory polymer based on crystalline side chain

In this study, a new type of a brush polyurethane containing long carbon side chains is prepared using hexamethylene diisocyanate (HDI), tetraethylene glycol (TEG), and a quaternized dihydroxyl glycol, which is previously synthesized from N-methyldiethanolamine (MDEA) and brominated alkanes. Results revealed that the brush-like polyurethane exhibits a good shape memory performance, with a shape recovery of 85%. The quaternization of long-chain alkanes onto tertiary ammonium nitrogen renders good self-healing properties to the brush polyurethane. Therefore, these thermal-induced self-healing properties are expected to make shape memory polyurethanes a good potential candidate for applications in smart coatings, smart surfaces, and other smart materials.

Investigation of the Dyeability of Cotton Fabrics with a Halochromic Dye According to Exhaust and Padding Methods

ABSTRACT Smart textiles are an important field in textile since these products are high-added value. One of the applications of smart textiles is chromic textiles, which can be used as a sensor. As is known, exhaust and padding dyeing are the basic methods and for this reason in this study process optimization for application of a halochromic dye (bromcresol purple) to cotton by these methods was carried out. According to experimental results, it can be said that dyeings according to exhaust method using wool dyeing process was successful for cationized cotton. On the other hand, pigment dyeing process used by garment dyers did not give satisfactory results in terms of fastness. In addition, the optimum conditions for padding method were determined as 5 g/L dye and 20 g/L binder. Fabrics showed very good color changing ability with regard to pH both with acid-base solutions and acid-base vapors. Accordingly, it can be said that both exhaust and padding methods can be used for dyeing with halochromic dyes, if optimum conditions are determined.

Smart Textiles Based on MoS2 Hollow Nanospheres for Personal Thermal Management.

Two-dimensional transition metal dichalcogenides are of particular interest in high-performance photothermal conversion, yet there remains a huge challenge in their practical application in smart textiles for healthcare, energy, and personal protection. Herein, we controllably prepared MoS2 hollow nanospheres with a high photothermal conversion efficiency of 36% via a microemulsion-hydrothermal method, which was further applied to construct photothermal fibers for personal thermal management after a hot-blast dip-drying process. Because of the prominent photothermal effect, the temperature of the photothermal fibers sharply increases from the room temperature value of 25.0 to 55.5 °C in 60 s under near-infrared illumination with a power density of 500 W/cm2. Furthermore, the photothermal fiber pad demonstrated an obvious temperature enhancement of 38.0 °C from a skin temperature of 22.0 °C after it was irradiated by natural sunlight for 60 s. Significantly, the antibacterial elimination rates of the photothermal fibers for Escherichia coli and Staphylococcus aureus are ∼99.9 and ∼99.8%, respectively. This strategy affords an avenue toward the practical application of photothermal materials in smart fibers for personal thermoregulation.

Development of upholstery electro-fabric for smart textile applications

Smart textile products developed by evaluating the human body’s data through sensors have become widespread in recent years. The majority of these products include textile-based information and communication technologies that integrate electronic components into clothing. People use seats, chairs, armchairs, etc., to sit constantly in vehicles, work or at home. The use of these items varies according to the requirements and purposes. In this study, an electro-textile-based upholstery fabric design was carried out to be used in sitting furniture. Electronic components containing capacitive sensors were placed in the designed fabric structure to make it usable in different areas where upholstery fabrics are used. In addition, the sensor connection circuit was developed to receive data from the fabric surface. The data taken from the fabric surface were made meaningful using the calibration and normalization algorithm. The 3D pressing map of the reaction on the fabric surface for different sitting positions was drawn. Electromagnetic field and vibration tests were carried out to examine the response behaviour in different environments where the fabric can be used. According to the findings, it was observed that the pressing areas formed on the surface were displayed in a significant way over the 3D pressing map, and the system was not affected by the electromagnetic field and vibrations. Besides, the fabric was applied on the various surfaces to test calibration and threshold algorithm. Obtained results and circumstances showed that the designed calibration and threshold algorithm were successful to obtained significant results. As a result of the study, upholstery electro fabric with a response time of 0.01 seconds in data collection was developed, which can be used in different environments such as home, workplace and vehicle. It can be used over furniture and in wet and dry conditions and is not affected by the electromagnetic field and vibration in the environment.