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In this study, bisphenol A epoxy resin, 1,6-Hexanediol diacrylate (HDDA), and 2,4,6-Trimethylbenzoyl-diphenylphosphine oxide (TPO) were utilized as a prepolymer, diluent, and photoinitiator, respectively, to prepare a light curing system with different amount of phosphor, which was used in place of conventional inorganic fillers. Phosphor was utilized to improve the precision of the material molded parts during the light curing process and enhance the mechanical properties of the molded parts owing to the ultraviolet (UV) absorption properties of phosphor, which prevented UV damage to the material, thus improving the light aging resistance and stability of the molded parts. Results revealed that the addition of 3% phosphor optimized the mechanical properties of the material (a maximum tensile strength of 42.43 MPa). Additionally, the material achieved the lowest linear (4.1%) and volumetric (0.58%) shrinkage at a phosphor content of 6%. This study provides a new insight into three-dimensional (3D) printing resin for stereolithography and provides a reference for the improvement of 3D printing products. KEYWORDS fluorescent resin, phosphor, photocurable resin, stereolithography 3D printing, 1 | INTRODUCTION Three-dimensional (3D) printing technology [1-6] is a flexible and powerful advanced manufacturing technology that emerged in recent years. This technology has been widely used in numerous countries [...]

Herein, the performance of silicone-modified 3D printing photosensitive resin was examined. Bisphenol-A epoxy acrylate (EA) was used as the substrate and isophorone diisocyanate, hydroxy-silicone oil, and hydroxyethyl acrylate were used as the raw materials. A silicone intermediate was synthesized to modify the substrate to prepare the 3D printing photosensitive material. The as-synthesized materials were characterized using Fourier transform infrared spectroscopy and scanning electron microscopy. The tensile fracture morphology was also analyzed. The effects of the addition of silicone intermediates on the mechanical properties, thermal stability, and shrinkage of the prepared 3D printing photosensitive resins were investigated. The results showed that an organosilicone group was successfully introduced into the side chain of EA. When the ratio of n(silicone):n(EA) is 0.3:1, the material has a high impact strength of 19.4 kJ·m−2, which is 32.8% higher than that of the pure resin; in addition, the elongation at break is 8.65% (compared to 6.56% of the pure resin). The maximum thermal weight loss temperature is 430.33°C, which is 6°C higher than that of the pure resin.

Removal of Cu2+ ions from contaminated water is an important but challenging task. This study reports the synthesis of a composite hydrogel from two natural polysaccharides, namely, sodium alginate and chitosan, using inexpensive kaolin as a raw material and polyacrylamide as a modifier. The hydrogel had a high adsorption capacity and selectivity for Cu2+. The composite hydrogel was characterized by Fourier transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy. The pseudo-second-order kinetic model was the most suitable model for the kinetic results, and the Langmuir isotherm model was the most representative of the sorption system. The results revealed that the adsorption process was mainly controlled by chemisorption. The maximum adsorption capacity of the adsorbent was 106.4 mg·g−1. Therefore, this study presents a new perspective on the application of composite hydrogels as Cu2+ adsorbents.

Dynamic tracking of spinal instrumentation could facilitate real-time evaluation of hardware integrity and in so doing alert patients/clinicians of potential failure(s). Critically, no method yet exists to continually monitor the integrity of spinal hardware and by proxy the process of spinal arthrodesis; as such hardware failures are often not appreciated until clinical symptoms manifest. Accordingly, herein, we report on the development and engineering of a bio-adhesive metal detector array (BioMDA), a potential wearable solution for real-time, non-invasive positional analyses of osseous implants within the spine. The electromagnetic coupling mechanism and intimate interfacial adhesion enable the precise sensing of the metallic implants position without the use of radiation. The customized decoupling models developed facilitate the precise determination of the horizontal and vertical positions of the implants with incredible levels of accuracy (e.g., <0.5 mm). These data support the potential use of BioMDA in real-time/dynamic postoperative monitoring of spinal implants. No method exists for real-time evaluation of the status of spinal implants. Here, the authors developed a bio-adhesive metal detector array (BioMDA) that provides a wearable, non-invasive solution for positional analyses of osseous implants within the spine. [ABSTRACT FROM AUTHOR]

In this study, H4Ti5O12@CNT ion sieves with an encapsulated structure were fabricated by combining pretreated carbon nanotubes (CNTs) as a template and carbon source, C16H36O4Ti as a titanium source, and CH3COOLi as a lithium source. By characterizing and analyzing the pretreated and untreated CNTs, numerous COOH and OH functional groups were introduced into the pretreated CNTs, which improved their dispersion in aqueous solutions and ethanol and facilitated the adsorption of lithium ions. The ion sieves prepared with the precursor roasted at 700 °C showed the best adsorption performance. Moreover, the structural integrity of the ion sieves was not affected by acid washing. For the first adsorption cycle, the ion sieves had a lithium‐ion saturated adsorption capacity of 32.32 mg/g. After five adsorption–desorption cycles, the adsorption capacity only decreased by 5.1% to 30.68 mg/g, which shows that they had good cycling stability. [ABSTRACT FROM AUTHOR]

Flexible and bio‐integrated electronics have attracted great attention due to their enormous contributions to personalized medical devices. Power sources, serving as one of the most important components, have been suffering from many problems, including deficient biocompatibility, poor stretchability, and unstable electrical outputs under deformed conditions, which limits the practical applications in flexible and bio‐integrated electronics. Here, we reported a fully stretchable magnesium (Mg)–air battery based on dual‐ions‐conducting hydrogels (SDICH). The high‐performance battery enables long‐term operation with lighting 120 lighting emitting diodes (LEDs) for over 5 h. Benefiting from the advanced materials and mechanical designs, the battery exhibits stability electrical outputs under stretching, which allows to operate ordinarily under various mechanical deformations without performance decay. Furthermore, the great biocompatibility of the battery offers great opportunity for biomedical applications, which is demonstrated by a self‐adaption wound dressing system. The in vitro and in vivo results prove that the self‐adaption wound dressing can effectively prevent wound inflammation and promote wound healing. By exploiting thermal feedback mechanics, the system can adjust antibiotic release rate and dosage spontaneously according to the real‐time wound conditions. The proposed fully stretchable Mg–air battery and self‐adaption wound dressing display great potential in skin‐integrated electronics and personalized medicine. [ABSTRACT FROM AUTHOR]

Multimodal force identification by electronic skin (E‐skin) provides comprehensive and precise tactile information that can enhance elaborated functions of fine tactile discrimination, robotic manipulation, and gesture recognition. However, it remains a great challenge to realize such complicated functions from a highly simplified E‐skin sensing system. Here, mimicking the multi‐mechanoreceptor synergistic effect in human skin, a simple, thin, soft, intelligent tactile sensor composed of an asymmetrically arrangement of strain sensing units array for multimodal tactile information decoding is reported. The E‐skin type tactile sensor exhibits good performance with excellent sensitivity for shear force (2.5 N–1), vertical force (0.11 kPa–1), that enables 3D force refactoring, as well as accurate recognition of sliding force for direction tracking. Another unique feature of the E‐skin type tactile sensor is the side force screen effect, that allows the tactile sensor to yield great accuracy and a gauge factor of 1492 in strain measuring. Furthermore, integration of the sensors into E‐skin array offers the capability of capturing dynamic and real‐time stress distribution on the hand in various conditions. This work provides a new route for complex force‐sensing from the simple structure and shows great potential in robotics, human‐machine interface, and virtual reality/augmented reality (VR/AR). [ABSTRACT FROM AUTHOR]