scholarly journals Dye Clicked Thermoplastic Polyurethane as a Generic Platform toward Chromic-Polymer Applications

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Eunbyeol Seo ◽  
Jihyun Choi ◽  
Bumjae Lee ◽  
Young-A Son ◽  
Kyung Jin Lee

AbstractChromic dyes responding against external stimuli are useful in various field of applications especially to colorimetric sensors. However, there have been several limitations in generic application because of its cost, stability and reliability. Here, we introduced highly functionalizable polymeric materials as a supporter covalently modified with controlled amount of chromic dyes. The photochromic organic dye (spiropyran) and highly functional thermoplastic polyurethanes (TPU) have been adopted as a representative example. Conventional polymeric solution processes such as film processing, wet-spinning, electrospinning and ink-writing are readily applicable because dye-TPU maintains its own solubility in various organic solvents. Additionally, since the concentration of dye on TPU are precisely controllable, these dye-TPU solution can be adopted in broad range of specific applications, such as secret coding, smart fabric, and chromic polymeric film layer.

2007 ◽  
Vol 2 (4) ◽  
pp. 155892500700200 ◽  
Author(s):  
Jaewoong Lee ◽  
R. M. Broughton ◽  
S. D. Worley ◽  
T. S. Huang

Cellulose and m-aramid were dissolved in an ionic liquid, and dry-jet wet spinning was employed to prepare composite fibers which could be rendered antimicrobial through exposure to chlorine bleach. The small domains of the m-aramid allowed a much higher accessibility and degree of chlorination than has been reported even for 100% m-aramid fibers. The mechanical properties including denier, tenacity, and strain at break were evaluated. The chlorinated composite fiber inactivated both Gram-positive and Gram-negative bacteria. The antimicrobial activity was retained after repeated washing and recharging.


Nanoscale ◽  
2019 ◽  
Vol 11 (13) ◽  
pp. 5884-5890 ◽  
Author(s):  
Zuoli He ◽  
Gengheng Zhou ◽  
Joon-Hyung Byun ◽  
Sang-Kwan Lee ◽  
Moon-Kwang Um ◽  
...  

In this manuscript, we report a novel highly sensitive wearable strain sensor based on a highly stretchable multi-walled carbon nanotube (MWCNT)/Thermoplastic Polyurethane (TPU) fiber obtained via a wet spinning process.


2020 ◽  
Vol 10 (24) ◽  
pp. 9057
Author(s):  
Paula Veske ◽  
Pieter Bauwens ◽  
Frederick Bossuyt ◽  
Tom Sterken ◽  
Jan Vanfleteren

The smart textiles and wearable technology markets are expanding tirelessly, looking for efficient solutions to create long-lasting products. The research towards novel integration methods and increasing reliability of wearables and electronic textiles (e-textiles) is expanding. One obstacle to be tackled is the washability and the endurance to mechanical stresses in the washing machine. In this article, different layering of thermoplastic polyurethane (TPU) films and knit fabrics are used to integrate three different designs of stretchable copper-based meander tracks with printed circuit boards. The various combinations are washed according to the ISO 6330-2012 standard to analyze their endurance. Results suggest that one meander design withstands more washing cycles and indicate that the well-selected layer compositions increase the reliability. Higher stretchability together with greater durability is accomplished by adding an extra meander-shaped TPU film layer.


Materials ◽  
2019 ◽  
Vol 12 (19) ◽  
pp. 3065 ◽  
Author(s):  
Kim ◽  
Park ◽  
Won ◽  
Jeon ◽  
Wie

In recent years, jointless soft robots have demonstrated various curvilinear motions unlike conventional robotic systems requiring complex mechanical joints and electrical design principles. The materials employed to construct soft robots are mainly programmable anisotropic polymeric materials to achieve contactless manipulation of miniaturized and lightweight soft robots through their anisotropic strain responsivity to external stimuli. Although reviews on soft actuators are extensive, those on untethered soft robots are scant. In this study, we focus on the recent progress in the manipulation of untethered soft robots upon receiving external stimuli such as magnetic fields, light, humidity, and organic solvents. For each external stimulus, we provide an overview of the working principles along with the characteristics of programmable anisotropic materials and polymeric composites used in soft robotic systems. In addition, potential applications for untethered soft robots are discussed based on the physicochemical properties of programmable anisotropic materials for the given external stimuli.


2019 ◽  
Vol 13 (4) ◽  
pp. 343-348
Author(s):  
Adam Gnatowski ◽  
Rafał Gołębski ◽  
Piotr Sikora

A comparative analysis of the thermomechanical properties of semicrystalline and amorphous polymeric materials was carried out. Samples were produced by using a 3D printing technology on the SIGNAL printer - ATMAT. The following polymeric materials were used to make the samples: TPU-thermoplastic polyurethane elastomer, ABScopolymer acrylonitrile-butadiene-styrene, Nosewood, PET-ethylene terephthalate, PLA-poly (lactic acid). The research included a thermal analysis of the dynamic properties (DMTA) of manufactured materials.


Author(s):  
Nga Thi-Hong Pham

Ductility and tensile strength are among the basic mechanical properties of polymers. Generally, it is difficult to enhance the ductility without significantly reducing the tensile strength. In this study, thermoplastic polyurethane (TPU) is mixed with 0%, 2.5%, 5%, 7.5%, 10%, and 12.5% polyamide 6 (PA6). The results show that the sample containing 100% TPU has the largest elongation of 690.5%. When PA6 is added, the elongation decreases gradually to 635.0%, 623.1%, 529.5%, 476.0%, 391.3%, and 242.8%, corresponding to 2.5%, 5%, 7.5%, 10%, 12.5%, and 100% PA6, respectively. The tensile strengths are 36.7, 33.8, 29.4, 26.5, 23.1, and 24.9 MPa, corresponding to 0%, 2.5%, 5%, 7.5%, 10%, and 12.5% PA6 samples, respectively. The tensile strength decreases gradually when the PA6 content is increased. Notably, the tensile strength of the 12.5% PA6 sample increases compared to the 10% PA6 sample. In addition, the hardness of the TPU/PA blend increases slightly as the PA6 ratio is increased. Finally, scanning electron microscope images demonstrate that PA6 particles act as particles dispersed or dissolved in TPU/PA blends.


Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2334
Author(s):  
Ewa Głowińska ◽  
Paulina Kasprzyk ◽  
Janusz Datta

Bio-based polymeric materials and green routes for their preparation are current issues of many research works. In this work, we used the diisocyanate mixture based on partially bio-based diisocyanate origin and typical petrochemical diisocyanate for the preparation of novel bio-based thermoplastic polyurethane elastomers (bio-TPUs). We studied the influence of the diisocyanate mixture composition on the chemical structure, thermal, thermomechanical, and mechanical properties of obtained bio-TPUs. Diisocyanate mixture and bio-based 1,4-butanediol (as a low molecular chain extender) created bio-based hard blocks (HS). The diisocyanate mixture contained up to 75 wt % of partially bio-based diisocyanate. It is worth mentioning that the structure and amount of HS impact the phase separation, processing, thermal or mechanical properties of polyurethanes. The soft blocks (SS) in the bio-TPU’s materials were built from α,ω-oligo(ethylene-butylene adipate) diol. Hereby, bio-TPUs differed in hard segments content (c.a. 30; 34; 40, and 53%). We found that already increase of bio-based diisocyanate content of the bio-TPU impact the changes in their thermal stability which was measured by TGA. Based on DMTA results we observed changes in the viscoelastic behavior of bio-TPUs. The DSC analysis revealed decreasing in glass transition temperature and melting temperature of hard segments. In general, obtained materials were characterized by good mechanical properties. The results confirmed the validity of undertaken research problem related to obtaining bio-TPUs consist of bio-based hard building blocks. The application of partially bio-based diisocyanate mixtures and bio-based chain extender for bio-TPU synthesis leads to sustainable chemistry. Therefore the total level of “green carbons” increases with the increase of bio-based diisocyanate content in the bio-TPU structure. Obtained results constitute promising data for further works related to the preparation of fully bio-based thermoplastic polyurethane elastomers and development in the field of bio-based polymeric materials.


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