Soft and Flexible Bilayer Thermoplastic Polyurethane Foam for Development of Bioinspired Artificial Skin

Li, Huan; Sinha, Tridib Kumar; Oh, Jeong Seok; Kim, Jin Kuk

doi:10.1021/acsami.8b01026

Cited by 50 publications

(31 citation statements)

References 63 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Alternatively, dielectric foams offer high contact electrification area with facile processing and scalability. [94] A hierarchical porous structure of the TENG delivers higher output efficiency when compared to the conventional molded microporous counterparts. [95] 3.1.9.…”

Section: Dielectric Foamsmentioning

confidence: 99%

Energy Harvesting and Storage with Soft and Stretchable Materials

et al. 2021

View full text Add to dashboard Cite

Soft robotics can interact with humans safely. 3) Devices built from stretchable materials have a greater mechanical degree of freedom. This allows electronics, displays, and sensors to be integrated into places that would be difficult or impossible with rigid devices and enables new types of human-computer interfaces. It also allows robotics to have enhanced levels of dexterity and complexity in movement (consider the octopus as an inspiring example). 4) Devices that can be deformed elastically can be engineered to have new or emerging properties, such as antennas that change frequency with elongation, [21] intelligent materials that can perform unconventional forms of logic, [22,23] or composites that change thermal conductivity, [24] electrical conductivity, [25] or dielectric properties with deformation. [26][27][28] Most robotic and electronic devices require electricity to function, as shown on the left side of Figure 1A. Electricity can power sensors, enable computation, drive locomotion, and transmit information. Although most devices use electricity from an outlet, such "tethered" devices create notable limitations. In addition to limiting the degree of freedom of robotic materials, plug-in devices must be within a chords-length of a functioning outlet, thereby confining the range of use of such devices. Although battery operated devices can operate for some time without being plugged-in, the need to do so periodically is at best a nuisance that limits the operating time of a device. At worst, it can lead to issues such as lack of compliance with wearable devices (that is, the device is taken off for charging and never put back on) or disruptions in operation (a particular problem for health care devices or remotely deployed devices). Thus, there is a compelling interest in harvesting energy from the ambient to create tetherless devices or even devices that need less charging. Figure 1A (right side) provides examples of applications that may benefit from harvesting, such as internetof-things (IOT) devices, soft robots, wearables, implantables, and deployables (that is, devices sent to remote locations that do not have electrical outlets). Energy Harvesting CategoriesStrategies to harness energy typically convert waste or otherwise unused energy from the ambient into electricity. Although This review highlights various modes of converting ambient sources of energy into electricity using soft and stretchable materials. These mechanical properties are useful for emerging classes of stretchable electronics, e-skins, bio-integrated wearables, and soft robotics. The ability to harness energy from the environment allows these types of devices to be tetherless, thereby leading to a greater range of motion (in the case of robotics), better compliance (in the case of wearables and e-skins), and increased application space (in the case of electronics). A variety of energy sources are available including mechanical (vibrations, human motion, wind/fluid motion), electromagnetic (radio frequency (RF), solar), and ther...

show abstract

Section: Dielectric Foamsmentioning

confidence: 99%

Energy Harvesting and Storage with Soft and Stretchable Materials

et al. 2021

View full text Add to dashboard Cite

show abstract

“…For example, microcellular polyurethane (PU) foam and thermoplastic polyurethane (TPU) foam were used as positive materials. [79][80][81] Saadatnia et al 82 used the polyurethane aerogel (PUA) that they have developed as the main contact material of TENG systems. Figure 5J shows the manufacturing process of PUA.…”

Section: Organic Aerogelmentioning

confidence: 99%

Aerogel based nanogenerators: Production methods, characterizations and applications

Korkmaz

Kariper

2020

Int J Energy Res

View full text Add to dashboard Cite

Thanks to the nanogenerators known as state-of-the-art energy collecting devices, the mechanical energy in every environment can be converted into electrical energy. Some studies on the improvement of the performance of triboelectric and piezoelectric nanogenerators that convert mechanical energy to electrical energy revealed that aerogels brought significant outcomes in the development of nanogenerators. Aerogels, the lightest solid material known, provides a large surface area as the contact area of the nanogenerators, its adjustable porosity allows to improve electronic properties of the nanogenerators, showing its significance in electronics once again. At the same time, the use of aerogels, which is the best candidate in terms of flexibility and mechanical strength required in wearable electronics, in the production of nanogenerators continues to attract the attention of researchers. This study includes an introduction of aerogels and the discussions on the studies involving aerogel based nanogenerators. In the paper, the studies in the literature, focusing on the advantages of aerogel based nanogenerators and their current applications were collected. Three different types of aerogel nanogenerators production were observed to be produced. They are all based on aerogel electrodes produced from different materials, and the paper outlines them with basic working principles. This classification of aerogel nanogenerators and outlining the results will make a significant contribution to the literature and will be a good source for researchers who want to work in this field.

show abstract

“…Thermoplastic polyurethane (TPU) is widely used in elastomers, adhesives, foams and other fields 1–4 due to its excellent performances, such as high strength, good wear resistance, adjustable performance and convenient synthesis 5–9 ; it also has the advantages of repeatable processing 10 . However, the fatal defect is also obvious that the mechanical properties are damaged during the processing at high‐temperature 11,12 .…”

Section: Introductionmentioning

confidence: 99%

Thermoplastic polyurethane with good mechanical and processing performances via blocking and deblocking of isocyanates

Han

Pei

et al. 2021

J of Applied Polymer Sci

View full text Add to dashboard Cite

Increasing the molecular weight of polyurethanes (PU) is an effective way to improve its mechanical properties, while, it is at the expense of sacrificing processability. Congruent modification in both mechanical and processing performances is still a challenge. Here, bis‐phenol‐A (BPA) derivatives, including tetrachlorobisphenol‐A and tetrabromobisphenol‐A, were chosen as the extender to synthesize thermoplastic PUs (TPU) containing blocked isocyanate units. This blocked isocyanate has a temperature‐responsive reversible reaction due to phenol urethane bonds, so as to ensure the good mechanical properties at the service temperature and better processing performance via deblocking into smaller molecular weight at the processing temperature; in addition, negative induction effect of the halogen substituents endow BPA derivatives with deblocking reaction at lower temperature. The experimental results confirmed that the blocking reaction carried out completely at 70°C, and accompanying by the dramatical increase of molecular weight. The obvious deblocking reaction happened at 140°C, where the average molecular weight of TPUs decreased from 22,600 g/mol to 13,690 g/mol. Meanwhile, the melt flow index increased significantly with the extension of heating time, indicating that the PU has good processing properties. After the deblocking and re‐blocking reactions were repeated alternatively, there is almost no change in its tensile properties, molecular weight and melt outflow index within two cycles under air atmosphere. This article proposes a strategy of congruent modification in both mechanical and processing performances of TPU.

show abstract

Soft and Flexible Bilayer Thermoplastic Polyurethane Foam for Development of Bioinspired Artificial Skin

Cited by 50 publications

References 63 publications

Energy Harvesting and Storage with Soft and Stretchable Materials

Energy Harvesting and Storage with Soft and Stretchable Materials

Aerogel based nanogenerators: Production methods, characterizations and applications

Thermoplastic polyurethane with good mechanical and processing performances via blocking and deblocking of isocyanates

Contact Info

Product

Resources

About