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Advanced Materials (Deerfield Beach,... Nov 2021Fiber electronics with mechanosensory functionality are highly desirable in healthcare, human-machine interfaces, and robotics. Most efforts are committed to optimize...
Fiber electronics with mechanosensory functionality are highly desirable in healthcare, human-machine interfaces, and robotics. Most efforts are committed to optimize the electronically readable interface of fiber mechanoreceptor, while the user interface based on naked-eye readable output is rarely explored. Here, a scalable fiber electronics that can simultaneously visualize and digitize the mechanical stimulus without external power supply, named self-powered optoelectronic synergistic fiber sensors (SOEFSs), are reported. By coupling of space and surface charge polarization, a new mechanoluminescent (ML)-triboelectric synergistic effect is realized. It contributes to remarkable enhancement of both electrical (by 100%) and optical output (by 30%), as well as novel temporal-spatial resolution mode for motion capturing. Based on entirely new thermoplastic ML material system and spinning process, industrial-level continuously manufacture and recycling processes of SOEFS are realized. Furthermore, SOEFSs' application in human-machine interface, virtual reality, and underwater sensing, rescue, and information interaction is demonstrated.
Topics: Electric Power Supplies; Electrodes; Electronics; Equipment Design; Fluorocarbon Polymers; Luminescent Measurements; Nanofibers; Optical Fibers; Polyvinyls; Wearable Electronic Devices
PubMed: 34558123
DOI: 10.1002/adma.202104681 -
Macromolecular Rapid Communications Aug 2021Currently, high strength nacre-inspired PVA/MMT (polyvinyl alcohol/montmorillonite) nanocomposites with high MMT nanofiller content (50-70 wt%) have been constructed...
Currently, high strength nacre-inspired PVA/MMT (polyvinyl alcohol/montmorillonite) nanocomposites with high MMT nanofiller content (50-70 wt%) have been constructed successfully. However, this seriously sacrifices the elongation and reduces the corresponding transparency. In this paper, high elongation and transparent PVA/MMT nanocomposites with high MMT content are prepared by the evaporation-induced assembly with the introduction of the micro-crosslinking. Results demonstrate that the micro-crosslinking can inhibit the formation of rod-shaped arrays, and contribute to a more ordered layered microstructure, where an elongation of 76.2% in 47.8 wt% MMT content nanocomposites is gained, nearly 19 times of that of non-crosslinked nanocomposites (ultimate strain is 4.1%). This provides a potential approach for compromise between high strength and excellent elongation at the same MMT content. Moreover, disappearance of rod-shaped arrays and resultant ordered layered microstructure make eventual films more transparent.
Topics: Bentonite; Nacre; Nanocomposites; Polyvinyl Alcohol
PubMed: 34240517
DOI: 10.1002/marc.202100229 -
Applied Biochemistry and Biotechnology Mar 2022More and more industries demand environmental friendliness. Silkworm pupae oil (SPO), extracted from the desilked silkworm pupae, can serve as a promising substrate...
More and more industries demand environmental friendliness. Silkworm pupae oil (SPO), extracted from the desilked silkworm pupae, can serve as a promising substrate alternative to use in plasticization. This study aimed to prepare epoxidized silkworm pupae oil (ESPO) and investigate their effects on the thermal stability and plasticization of polyvinyl chloride (PVC) films. A chemo-enzymatic method of ESPO was developed in the presence of Lipase SMG1-F278N and HO in natural deep eutectic solvents (DESs). Lipase SMG1-F278N could initiate the epoxidation reaction effectively at room temperature with a negligible loss of activities 10 batches. A maximum oxirane value of 6.94% was obtained. The formation of oxirane ring in ESPO was confirmed by FTIR and C NMR spectra. Moreover, ESPO showed a better thermal stability and lower freezing point than epoxidized soybean oil (ESO). It was demonstrated that ESPO had a good frost resistance. In addition, ESPO showed a significantly improved plasticizing effect on flexible polyvinyl chloride (PVC). Compared with ESO, ESPO could increase the tensile elongation at break effectively. A significantly lower migration rate of plasticizer was observed in PVC plasticized with ESPO.
Topics: Polyvinyl Chloride
PubMed: 34677760
DOI: 10.1007/s12010-021-03715-5 -
Physical and Engineering Sciences in... Sep 2023TMP is gradually becoming a fundamental element for quality assurance and control in ionizing and non-ionizing radiation imaging modalities as well as in the development...
TMP is gradually becoming a fundamental element for quality assurance and control in ionizing and non-ionizing radiation imaging modalities as well as in the development of different techniques. This study aimed to evaluate and obtain polyvinyl chloride tissue mimicking material for dual-modality breast phantoms in mammography and ultrasound. Breast tissue equivalence was evaluated based on X-ray attenuation properties, speed of sound, attenuation, and acoustic impedance. There are six samples of PVC-plasticizer material with variations of PVC concentration and additives. The evaluation of X-ray attenuation was carried out using mammography from 23 to 35 kV, while the acoustic properties were assessed with mode A ultrasound and a transducer frequency of 5 MHz. A breast phantom was created from TMP material with tissue equivalence and was then evaluated using mammography as well as ultrasound to analyze its image quality. The results showed that samples A (PVC 5%, DOP 95%), B (PVC 7%, DOP 93%), C (PVC 10%, DOP 90%), E (PVC 7%, DOP 90%, graphite 3%), and F (PVC 7%, DOP 90%, silicone oil 3%) have the closest equivalent to the ACR breast phantom material with a different range of 0.01-1.39 in the 23-35 kV range. Based on the evaluation of the acoustic properties of ultrasound, A had high similarity to fat tissue with a difference of 0.03 (dB cm MHz) and 0.07 (10 kg m s), while B was close to the glandular tissue with a difference of 9.2 m s. Multilayer breast phantom images' results showed gray levels in mammography and ultrasound modalities. Therefore, this study succeeded in establishing TMP material for mammography and ultrasound. It can also be used for simple quality assurance and control programs.
Topics: Polyvinyl Chloride; Ultrasonography; Mammography; Phantoms, Imaging; Adipose Tissue
PubMed: 37253939
DOI: 10.1007/s13246-023-01283-y -
European Journal of Pharmaceutics and... Sep 2020Many amorphous solid dispersions (ASDs) are thermodynamically unstable. Thus, the active pharmaceutical ingredient (API) might crystallize over time. The crystallization...
Many amorphous solid dispersions (ASDs) are thermodynamically unstable. Thus, the active pharmaceutical ingredient (API) might crystallize over time. The crystallization kinetics and therewith the long-term stability of ASDs depends on the storage conditions temperature and relative humidity (RH) as they determine the molecular mobility of the API in the polymer. To quantify the molecular mobility, the rheological behavior of two different ASDs with ibuprofen and either poly(vinyl acetate) or poly(vinylpyrrolidone-co-vinyl acetate) was analyzed as function of temperature and relative humidity by means of an oscillatory rheometer. The plasticizing effect of ibuprofen and absorbed water on the zero-shear viscosity of the polymer could be fully explained by the reduction of the glass-transition temperature of the mixture compared to the one of the pure polymer. Moreover, this work proposes an approach to predict the zero-shear viscosity of an ASD based on only the temperature dependence of the zero-shear viscosity of the pure polymer as well as the predicted water content in the ASD at certain RH using the Perturbed-Chain Statistical Associating Fluid Theory (PC-SAFT).
Topics: Anti-Inflammatory Agents, Non-Steroidal; Crystallization; Excipients; Humidity; Ibuprofen; Polyvinyls; Pyrrolidines; Rheology; Solubility; Vinyl Compounds; Viscosity
PubMed: 32717391
DOI: 10.1016/j.ejpb.2020.07.024 -
IEEE Transactions on Ultrasonics,... Mar 2020Up to now, low-frequency ultrasonic transducers have been manufactured using different materials and technologies and have been inspired by the biological world, mainly...
Up to now, low-frequency ultrasonic transducers have been manufactured using different materials and technologies and have been inspired by the biological world, mainly by the biosonar of dolphins and bats. Our research moves in this context, which is dedicated to investigating the feasibility of developing a piezopolymer sensor capable of covering the wide frequency range of a bat's biosonar. We propose an ultrasonic sensor manufactured using a sheet of polyvinylidene fluoride curved according to a logarithmic spiral geometry as it is present in biological models of the cochlea. Experiments were carried out both in transmission and reception, and demonstrated that a spiral-shaped transducer can transmit and receive ultrasonic signals similar to the specific vocalizations of most of the bats in the range between 20 and 80 kHz. The resonant frequencies of the transducer were evaluated through a finite element analysis, in agreement with experimental data covering the entire broadband. During transmission, the sound pressure level showed a maximum value of 90 dB, while during reception, the sensitivity spanned from t103.8 up to t89.1 dB. Directivity measurements demonstrated omnidirectional properties both on horizontal and vertical planes, representing a breakthrough in the field of broadband ultrasonic sensors.
Topics: Animals; Chiroptera; Cochlea; Echolocation; Equipment Design; Finite Element Analysis; Models, Biological; Polyvinyls; Transducers; Ultrasonics
PubMed: 31647427
DOI: 10.1109/TUFFC.2019.2948817 -
Nanomedicine (London, England) Mar 2021Due to the noninvasive nature of boron neutron capture therapy (BNCT), it is considered a promising cancer treatment method. To investigate whether polyvinyl...
Due to the noninvasive nature of boron neutron capture therapy (BNCT), it is considered a promising cancer treatment method. To investigate whether polyvinyl alcohol/boric acid crosslinked nanoparticles (PVA/BA NPs) are an efficient delivery system for BNCT. PVA/BA NPs were synthesized and cocultured with brain and oral cancers cells for BNCT. PVA/BA NPs had a boron-loading capacity of 7.83 ± 1.75 w/w%. They accumulated in brain and oral cancers cells at least threefold more than in fibroblasts and macrophages. The IC values of the brain and oral cancers cells were at least ninefold and sixfold lower than those of fibroblasts and macrophages, respectively. Theoretically, PVA/BA NPs target brain and oral cancers cells and could offer improved therapeutic outcomes of BNCT.
Topics: Boric Acids; Boron; Boron Compounds; Boron Neutron Capture Therapy; Nanoparticles; Polyvinyl Alcohol; Polyvinyls
PubMed: 33599549
DOI: 10.2217/nnm-2020-0401 -
Carbohydrate Polymers Nov 2023Accurate and controlled release of drug molecules is crucial for transdermal drug delivery. Electricity, as an adjustable parameter, offers the potential for precise and...
Accurate and controlled release of drug molecules is crucial for transdermal drug delivery. Electricity, as an adjustable parameter, offers the potential for precise and controllable drug delivery. However, challenges exist in selecting the appropriate drug carrier, electrical parameters, and release model to achieve controlled electronic drug release. To overcome these challenges, this study designed a functional hydrogel using polyvinyl alcohol, chitosan, and graphene oxide as components that can conduct electricity, and constructed a drug transdermal release model using fluorescein sodium salt with proper electrical parameters. The results demonstrated that the hydrogel system exhibited low cytotoxicity, good conductivity, and desirable drug delivery characteristics. The study also integrated the effects of drug release and tissue repair promotion under electrical stimulation. Cell growth was enhanced under low voltage direct current pulses, promoting cell migration and the release of VEGF and FGF. Furthermore, the permeability of fluorescein sodium salt in the hydrogel increased with direct current stimulation. These findings suggest that the carbohydrate polymers hydrogel could serve as a drug carrier for controlled release, and electrical stimulation offers new possibilities for functional drug delivery and transdermal therapy.
Topics: Hydrogels; Polyvinyl Alcohol; Graphite; Chitosan; Delayed-Action Preparations; Fluorescein; Polyvinyls; Drug Delivery Systems; Electricity; Drug Carriers; Oxides
PubMed: 37567713
DOI: 10.1016/j.carbpol.2023.121172 -
Organic Letters Dec 2022()- and ()-isocyanoalkenes were selectively synthesized via the sequential cross coupling of vinyl iodides with formamide, followed by dehydration. The optimal catalyst,...
()- and ()-isocyanoalkenes were selectively synthesized via the sequential cross coupling of vinyl iodides with formamide, followed by dehydration. The optimal catalyst, generated in situ from CuI and -dimethyl-1,2-cyclohexanediamine, rapidly coupled ()- or ()-vinyl iodides with formamide, which minimized the isomerization of the resultant vinyl formamide. The method efficiently provided a range of acyclic, carbocyclic, and heterocyclic isocyanoalkenes; the versatility is illustrated with the selective, stereodivergent syntheses of the diastereomeric isocyanoalkene antibiotics, B371 and -B371.
Topics: Anti-Bacterial Agents; Formamides; Iodides; Polyvinyl Chloride
PubMed: 36399331
DOI: 10.1021/acs.orglett.2c03461 -
Molecules (Basel, Switzerland) Feb 2023Presently, the rising concerns about the fossil fuel crisis and ecological deterioration have greatly affected the world economy and hence have attracted attention to... (Review)
Review
Presently, the rising concerns about the fossil fuel crisis and ecological deterioration have greatly affected the world economy and hence have attracted attention to the utilization of renewable energies. Among the renewable energy being developed, supercapacitors hold great promise in broad applications such as electric vehicles. Presently, the main challenge facing supercapacitors is the amount of energy stored. This, however, does not satisfy the increasing demand for higher energy storage devices, and therefore, intensive research is being undertaken to overcome the challenges of low energy density. The purpose of this review is to report on solid polymer electrolytes (SPEs) based on polyvinyl alcohol (PVA). The review discussed the PVA as a host polymer in SPEs followed by a discussion on the influence of conducting salts. The formation of SPEs as well as the ion transport mechanism in PVA SPEs were discussed. The application and development of PVA-based polymer electrolytes on supercapacitors and other energy storage devices were elucidated. The fundamentals of electrochemical characterization for analyzing the mechanism of supercapacitor applications, such as EIS, LSV and dielectric constant, are highlighted. Similarly, thermodynamic transport models of ions and their mechanism about temperature based on Arrhenius and Vogel-Tammann-Fulcher (VTF) are analyzed. Methods for enhancing the electrochemical performance of PVA-based SPEs were reported. Likely challenges facing the current electrolytes are well discussed. Finally, research directions to overcome the present challenges in producing SPEs are proposed. Therefore, this review is expected to be source material for other researchers concerned with the development of PVA-based SPE material.
Topics: Polyvinyl Alcohol; Polymers; Ethanol; Electrolytes; Salts
PubMed: 36838770
DOI: 10.3390/molecules28041781