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1.
Small ; 20(36): e2401658, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38693074

RESUMO

The formation process of biofouling is actually a 4D process with both spatial and temporal dimensions. However, most traditional antifouling coatings, including slippery liquid-infused porous surface (SLIPS), are limited to performing antifouling process in the 2D coating plane. Herein, inspired by the defensive behavior of sea anemones' wielding toxic tentacles, a "4D SLIPS" (FSLIPS) is constructed with biomimetic cilia via a magnetic field self-assembly method for antifouling. The bionic cilia move in 3D space driven by an external magnetic field, thereby preventing the attachment of microorganisms. The FSLIPS releases the gaseous antifoulant (nitric oxide) at 1D time in response to light, thereby achieving a controllable biocide effect on microorganisms. The FSLIPS regulates the movement of cilia via the external magnetic field, and controls the release of NO overtime via the light response, so as to adjust the antifouling modes on demand during the day or night. The light/magnetic response mechanism endow the FSLIPS with the ability to adjust the antifouling effect in the 4D dimension of 1D time and 3D space, effectively realizing the intelligence, multi-dimensionality and precision of the antifouling process.


Assuntos
Incrustação Biológica , Cílios , Anêmonas-do-Mar , Propriedades de Superfície , Cílios/efeitos dos fármacos , Cílios/fisiologia , Incrustação Biológica/prevenção & controle , Animais , Porosidade , Biônica , Óxido Nítrico/metabolismo
2.
Small ; : e2404605, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39248680

RESUMO

Artificial ion diodes, inspired by biological ion channels, have made significant contributions to the fields of physics, chemistry, and biology. However, constructing asymmetric sub-nanofluidic membranes that simultaneously meet the requirements of easy fabrication, high ion transport efficiency, and tunable ion transport remains a challenge. Here, a direct and flexible in situ staged host-guest self-assembly strategy is employed to fabricate ion diode membranes capable of achieving zonal regulation. Coupling the interfacial polymerization process with a host-guest assembly strategy, it is possible to easily manipulate the type, order, thickness, and charge density of each module by introducing two oppositely charged modules in stages. This method enables the tuning of ion transport behavior over a wide range salinity, as well as responsive to varying pH levels. To verify the potential of controllable diode membranes for application, two ion diode membranes with different ion selectivity and high charge density are coupled in a reverse electrodialysis device. This resulted in an output power density of 63.7 W m-2 at 50-fold NaCl concentration gradient, which is 12 times higher than commercial standards. This approach shows potential for expanding the variety of materials that are appropriate for microelectronic power generation devices, desalination, and biosensing.

3.
Chemistry ; 30(21): e202303096, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38140811

RESUMO

Poly(dimethylsiloxane) (PDMS) is widely used in marine antifouling coatings due to its low surface energy property. However, certain drawbacks of PDMS coatings such as poor surface adhesion, weak mechanical properties, and inadequate static antifouling performance have hindered its practical applications. Herein, condensation polymerization is utilized to prepare PDMS-based polythiamine ester (PTUBAF) coatings that consist of PDMS, polytetrahydrofuran (PTMG), 2, 3, 5, 6-tetrafluoro-1, 4-benzenedimethanol (TBD) as the main chains and isobornyl acrylate(IBA) as the antifouling group. The surface adhesion to the substrate is enhanced due to the hydrogen bond between the coated carbamate group and the hydroxyl group on the surface of the substrate. Mechanical properties of PTUBAF are significantly improved due to the benzene ring and six-membered ring biphase hard structure. The strong synergistic effect of bactericidal groups and low surface energy surface endows the PTUBAF coating with outstanding antifouling performance. Due to the low surface energy surface, the PTUBAF coatings are also found to possess excellent anti-corrosion. Furthermore, since the PTUBAF coatings exhibit a visible light transmittance of 91 %, they can applied as protective films for smartphones. The proposed method has the potential to boost the production and practical applications of silicone-based coatings.

4.
Chemistry ; : e202403116, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39292511

RESUMO

Biofouling and corrosion of submerged equipment caused by marine organisms severely restrict the rapid development of the marine industry. Traditional antifouling or anticorrosion coatings typically serve a sole purpose and exhibit limited degradability upon failure, rendering them inadequate for current demands. Herein, a novel imine-functionalized command-degradable bio-based epoxy coating (SAHPEP-DDM) with enhanced integrated antifouling and anticorrosion performances was synthesized utilizing 1,3-bis (3-aminopropyl)-1,1,3,3-tetramethyldisiloxane and syringaldehyde. Compared with commercial epoxy resins (E51-DDM) and polydimethylsiloxanes (PDMS), the SAHPEP-DDM coating exhibits superior antifouling and anticorrosion properties due to the existence of -C=N- and Si-O-Si chain segments in the cross-linking network. The coating shows promising resistance against bacteria, algae and proteins, as well as excellent corrosion resistance in artificial seawater. The coating also exhibits excellent chemical resistance in organic solvents as well as neutral and alkaline environments. Moreover, its controlled degradation after failure can be achieved in acid aqueous solutions through temperature and acidity adjustments, facilitated by the presence of -C=N-. This work presents a novel degradable coating successfully coupled the dual functions of antifouling and anticorrosion coatings, avoiding the employment of intermediate coat, indicating vast potential for application in marine engineering fields.

5.
Langmuir ; 40(36): 19195-19208, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39192631

RESUMO

The process of spraying water and flavorings on dry tobacco is an important factor in the industrial environment and product quality. Tobacco as a complex porous fiber material, the interfacial transfer process of water is complex. In this study, machine learning and image recognition techniques were utilized to quickly obtain the structural parameters of the tobacco surface and construct a cellular structure model of the tobacco surface. In situ observation of the droplet impact spreading process was carried out using a high-speed camera to explore the droplet dissipation dynamics on different surfaces. And the competing processes of droplet wetting and evaporation under the influence of surface microstructure were determined by combining experimental studies and finite element simulation calculations. Based on the characteristics of tobacco pore size distribution, the infiltration under gas-liquid two-phase action was transformed into single-phase flow transfer under capillary force, and the continuous droplet infiltration process was simulated. A parallel artificial membrane permeability measurement method of bionic tobacco waxy layer was constructed for the screening of spray dosing copenetrant. This study brings new insights into the wetting of porous fibrous materials and is important for exploring the wetting process and additive development process influenced by the microstructure.

6.
Small ; 19(25): e2301164, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36919943

RESUMO

In recent years, growing concerns regarding energy efficiency and heat mitigation, along with the critical goal of carbon neutrality, have drawn human attention to the zero-energy-consumption cooling technique. Passive daytime radiative cooling (PDRC) can be an invaluable tool for combating climate change by dispersing ambient heat directly into outer space instead of just transferring it across the surface. Although significant progress has been made in cooling mechanisms, materials design, and application exploration, PDRC faces challenges regarding functionality, durability, and commercialization. Herein, a silica nanofiber aerogels (SNAs) functionalized poly(vinylidene fluoride-co-hexafluoropropene) (P(VDF-HFP)) membrane (SFP membrane), inspired by constructional engineering is constructed. As-prepared membranes with flexible network structure combined hierarchical structure design and practicability principal. As the host material for thermal comfort management (TCM) and versatile protection, the SFP membrane features a large surface area, porous structure, and a robust skeleton that can render excellent mechanical properties. Importantly, the SFP membrane can keep exceptional solar reflectivity (0.95) and strong mid-infrared emittance (0.98) drop the temperature to 12.5 °C below ambient and 96 W m-2 cooling power under typical solar intensities over 910 W m-2 . This work provides a promising avenue for high performance aerogel membranes that can be created for use in a wide variety of applications.

7.
Langmuir ; 38(38): 11621-11630, 2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36107634

RESUMO

Clathrate hydrate growth, deposition, and plug formation during oil and gas transportation causes blockage of pipelines. An effective strategy to solve this problem is to mitigate the hydrate formation and reduce its adhesion on pipe walls through a coating process. However, durability failure, corrosion, inability to self-heal, high cost, and strong hydrate adhesion remain unsolved issues. To address these challenges, in this work, we present an in situ self-replenishing nonfluorinated durable hydrate-phobic coating of candle soot particles. The candle soot coating reduces hydrate adhesion by promoting a thick barrier film of hydrocarbons between the hydrate and the soot coated substrate. The hydrocarbons permeating the soot coating display a high contact angle for water and inhibit the formation of water bridges between the hydrate and soot coated substrate. The spherical cyclopentane hydrate slides off easily on the candle soot coating inside the cyclopentane environment. The hydrate former, cyclopentane-water emulsion, and THF-water mixture have high contact angles as well as low hydrate adhesion on soot coating simultaneously. In addition, the coating is flow-induced long-term slippery, durable, low cost, anticorrosion, self-cleaning, and suitable for practical applications.

8.
Clin Exp Rheumatol ; 40(12): 2350-2356, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36305348

RESUMO

OBJECTIVES: This study aimed to assess the diagnostic value of labial salivary gland changes in female patients with Sjögren's syndrome (SS) having different European League Against Rheumatism (EULAR) Sjögren's Syndrome Disease Activity Index (ESSDAI) and serological markers using conventional ultrasound and shear wave elastography (SWE). METHODS: A total of 82 female inpatients diagnosed with SS were retrospectively examined at the First Affiliated Hospital of Soochow University from July 2020 to December 2021. The patients were divided into two groups based on the ESSDAI score: remission group (ESSDAI <5) and active group (ESSDAI ≥5). The prognosis of patients was assessed using serological markers. The ultrasound examination of bilateral labial glands was performed in all patients to analyse the quantity and area of the largest single labial gland per unit detection range (Smax). The SWE of labial glands was performed in different groups. RESULTS: The Smax and quantity of labial glands on both sides were correlated with patient age in 82 female patients with SS. Emin, Emean and Emax of the remission group based on ESSDAI were significantly lower than the active group (p<0.001), and the areas under the receiver operating characteristic (ROC) curve for these three in diagnosing were 0.720, 0.728 and 0.734, respectively. The differences in Emean, Emin and Emax values of labial glands between the two groups of immunoglobulin G (IgG) <16g/L and IgG ≥16g/L were statistically significant (p<0.05), and the area under the ROC curve (AUC) for the three values were 0.825, 0.830, and 0.815, respectively. There were statistically significant differences (p<0.05) in Emin, Emean, and Emax of labial glands between the hypocomplementaemic and non-hypocomplementaemic groups, and the AUC for the three values were 0.840, 0.843, and 0.819, respectively. CONCLUSIONS: Conventional ultrasound and SWE of the labial gland can reflect the disease activity and prognosis of patients with SS, and more conveniently assess the progression in the patients and provide imaging evidence.


Assuntos
Técnicas de Imagem por Elasticidade , Síndrome de Sjogren , Humanos , Feminino , Síndrome de Sjogren/diagnóstico por imagem , Técnicas de Imagem por Elasticidade/métodos , Estudos Retrospectivos , Ultrassonografia/métodos , Prognóstico
9.
Langmuir ; 36(37): 10960-10969, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32864968

RESUMO

Polluted water is a worldwide problem; therefore, effective separation of oil/water and removal of dyes, organic micropollutants, and heavy metals in wastewater are the need of the hour. Herein, hydrophilic ß-cyclodextrin-grafted carboxymethyl cellulose, biodegradable polyvinyl alcohol, and chitosan were used as main raw materials to construct a multifunctional aerogel framework by simple sol-gel and directional freeze-drying methods. Featuring intrinsic superamphiphilic wettability in air, robust superoleophobic wettability underwater, and excellent shape-recovery characteristics, the biomass-derived aerogel presents durable oil/water separation even after 10 cycles. The aerogels possess prominent adsorption capacity for methyl blue, 1-naphthylamine, and Cu2+, which was as high as 121.55 mg/g, 33.96 mg/g, and 122.6 mg/g, respectively. In addition, various pollutant mixtures could be effectively adsorbed by the aerogel at the same time with the adsorption capacity of 121.75 mg/g for methyl blue, 0.97 mg/g for bisphenol A, and 20.11 mg/g for Cu2+.

10.
Langmuir ; 35(37): 11959-11967, 2019 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-30912432

RESUMO

Severe water pollution has placed a heavy burden on the ecological environment on which humans rely. Effective approaches to mitigating this worldwide issue are in great demand. Here in this work, an organic-inorganic bacterial cellulose aerogel was fabricated through a freeze-drying technique and a step-by-step coating method. The as-prepared aerogel possessed an intact three-dimensional porous structure, an ultralow density, and shape recovery performance. Ag2O nanoparticles were uniformly and firmly dispersed on the cellulose skeleton, endowing the as-prepared aerogel with an excellent photocatalytic degradation property of methylene blue and great recyclability. The aerogel with zwitterionic compounds attached through the effect of silane exhibited superhydrophilicity, superoleophilicity, and underwater superoleophobicity as well as underoil superhydrophobicity, and it could separate oil/water mixtures with high efficiency. This environmentally friendly bacterial cellulose aerogel equipped with multifunctionality showed great potential for wide application in water treatment fields.


Assuntos
Bactérias/química , Celulose/química , Purificação da Água/métodos , Géis , Óxidos/química , Compostos de Prata/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Molhabilidade
11.
Langmuir ; 34(13): 4052-4058, 2018 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-29528662

RESUMO

High durability, low cost, and superior anti-icing and active deicing multifunctional surface coatings, especially in the extreme environment, are highly desired to inhibit and/or eliminate the detriment of icing in many fields, such as automobile, aerospace, and power transmission. Herein, we first report a facile and versatile strategy to prepare novel slippery polyols-infused porous surfaces (SPIPS's) with the inexpensive polyols as the lubricant liquids. These SPIPS's are fabricated by a spray-coating approach based on amino-modified magnetic Fe3O4 nanoparticles (MNP@NH2) and amphiphilic P(poly(ethylene glycol) methyl ether methacrylate- co-glycidyl methacrylate) copolymer covalent cross-linked hybrids, followed by infusion with various polyols. The as-prepared surface exhibits excellent antifrosting property, that is, it can greatly postpone frost formation as long as 2700 s at -18 °C. Meanwhile, differential scanning calorimetry results clearly demonstrate that SPIPS's show a remarkable freezing point depression capacity and the crystallization point of water can be decreased as low as -36.8 °C. The SPIPS also displays an extremely low ice adhesion strength (0.1 kPa) due to its unique surface characteristics. Moreover, outstanding active thermal deicing property is achieved for these slippery surfaces because of intrinsically photothermal effect of magnetic Fe3O4 nanoparticle. Hence, these results indicate that this kind of multifunctional bioinspired slippery surface, with superb stability, good cost effectiveness, and easy fabrication, can be used as a promising candidate for anti-icing and deicing applications.

12.
Langmuir ; 34(50): 15425-15444, 2018 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-30445813

RESUMO

Ice formation and accretion on surfaces is a serious economic issue in energy supply and transportation. Recent strategies for developing icephobic surfaces are intimately associated with superwettability. Commonly, the superwettability of icephobic materials depends on their surface roughness and chemical composition. This article critically categorizes the possible strategies to mitigate icing problems from daily life. The wettability and classical nucleation theories are used to characterize the icephobic surfaces. Thermodynamically, the advantages/disadvantages of superhydrophobic surfaces are discussed to explain icephobic behavior. The importance of elasticity, slippery liquid-infused porous surfaces (SLIPSs), amphiphilicity, antifreezing protein, organogels, and stimuli-responsive materials has been highlighted to induce icephobic performance. In addition, the design principles and mechanism to fabricate icephobic surfaces with superwettability are explored and summarized.

13.
Langmuir ; 33(39): 10340-10350, 2017 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-28893069

RESUMO

In this work, a novel substrate building block, magnetic Fe3O4 nanoparticles armed with dopamine molecules were developed via mussel-inspired metal-coordination bonds. Combined with glycidyl methacrylate, polydimethylsiloxane propyl ether methacrylate, and diethylenetriamine, the original silicone oil swelling slippery liquid-infused porous surfaces (SLIPS) were first prepared by reversible coordinate bonds and strong covalent bonds cross-linking process. The matrix mechanical characteristics and surface physicochemical properties were systematically investigated. Results showed that the mechanical property of copolymer matrix and surface wettability of SLIPS can be remarkably recovered, which were due to the synergistic interactions of magnetic nanoparticles' intrinsic photothermal effect, reversible Fe-catechol coordination, and diffused lubricating liquid. After irradiating with sunlamp for 2 h and sequentially healing for 10 h under ambient conditions, the crack almost disappeared under optical microscopy with 78.25% healing efficiency (HEf) of toughness, and surface slippery was completely retrieved to water droplets. The efficient self-heal of copolymer matrix (66.5% HEf after eighth cutting-healing cycle) and recovering of slipperiness (SA < 5° and 5° < SA < 17° after fourth and eighth cutting-centrifuging-healing cycles, respectively) would extend longevity of SLIPS when subjected to multiple damages. Moreover, the prepared SLIPS displayed superb self-cleaning and liquid-repellent properties to a wide range of particulate contaminants and fluids.

14.
Langmuir ; 32(5): 1380-8, 2016 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-26780307

RESUMO

A novel amphiphilic fluorinated gradient copolymer was prepared by semibatch reversible addition-fragmentation chain transfer (RAFT) method using poly(ethylene glycol) methyl ether methacrylate (PEGMA) and 3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl acrylate (TFOA) as monomers. The resultant amphiphilic copolymers were then incorporated into the poly(ether sulfone) (PES) to fabricate PES blend membranes via the non-solvent-induced phase separation method (NIPS). During the phase inversion process, both hydrophilic (PEGMA) and low surface energy (TFOA) segments significantly enriched on the membrane surface by surface segregation to form an amphiphilic surface, which was demonstrated by surface wetting properties and X-ray photoelectron spectroscopy (XPS) measurements. According to the filtration experiments of oil-in-water emulsion, the heterogeneous membranes exhibited superior oil-fouling resistant properties, that is, low flux decay (as low as 15.4%) and high flux recovery (almost 100%), compared to the pure PES membrane. The synergistic effect of fouling-resistant and fouling-release mechanisms was found to be responsible for the excellent antifouling capacities. The findings of this study offer a facile and robust strategy for fabricating ultralow oil-fouling membranes that might be used for effective oil/water separation.

15.
Surg Innov ; 23(2): 124-9, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26092564

RESUMO

PURPOSE: The aim of this study was to assess the safety and effectiveness of laparoscopic common bile duct (CBD) exploration with a novel articulating forceps. METHODS: A retrospective analysis was carried out of 90 patients who underwent laparoscopic transcholedochal CBD exploration for choledocholithiasis between May 2006 and June 2014. Forty-five patients underwent laparoscopic choledocholithotomy using the routine instruments (group A). Forty-five patients underwent laparoscopic choledocholithotomy using the routine instruments plus the novel articulating forceps (group B). The 2 group populations were similar with regard to demographic data and clinical presentations. RESULTS: Laparoscopic transcholedochal CBD exploration was successful in all 90 patients. The mean diameter of the CBD was 14.42 mm in group A and 14.73 mm in group B (P > .05). The average number of stones extracted per patient was 4.22 in group A and 4.67 in group B (P > .05). The patients in group A had a significantly longer operative time than the patients in group B (109.38 vs 80.49 minutes; P < .01). The intraoperative blood loss was minimal in both groups, and no major complications were observed in either group. The mean hospitalization stay was 6.60 days in group A and 5.58 days in group B (P < .01). CONCLUSION: Laparoscopic transcholedochal CBD exploration with the novel articulating forceps is a safe and effective approach to the management of choledocholithiasis that offers a short operating time and short postoperative hospital stay.


Assuntos
Coledocolitíase/cirurgia , Coledocostomia/instrumentação , Laparoscopia/instrumentação , Adulto , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
16.
Langmuir ; 31(16): 4752-60, 2015 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-25851270

RESUMO

Novel fluorinated copolymers of stearyl acrylate (SA) and (perfluorohexyl)ethyl acrylate (C6A), (perfluorohexyl)ethyl methacrylate (C6MA), 2-[[[[2-(perfluorohexyl)]-sulfonyl]methyl] amino]ethyl acrylate (C6SA), and methacrylate (C6SMA) were synthesized via miniemulsion copolymerization. The extremely hydrophobic monomers perfluoroalkyl acrylate (FA) and SA acted as the reactive costabilizer in the miniemulsion system. The microstructure and surface wetting properties of the copolymers were characterized by (1)H NMR, FT-IR, and dynamic contact angle test. The crystallization behaviors and fine surface structures of the copolymer films were determined by differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXD) analysis. The self-assembled aggregation and roughness of the copolymer films were investigated by atomic force microscopy (AFM). The results showed that the fluorinated side chains interrupted and impeded the crystallizable side chains of SA from forming complete crystals. And the Tm and ΔHf of the copolymers were decreased as a consequence of this effect. The fluorinated side chains in P(C6A/SA) and P(C6MA/SA) arranged between the crystallizable hydrocarbon side chains of SA, while the crystallization structure of fluorinated and nonfluorinated pendant groups existed all at once in copolymers P(C6SA/SA) and P(C6SMA/SA). The four copolymers exhibited very low surface free energy and excellent dynamic water repellency attributed to the restriction of perfluoroalkyl groups combined with crystallization of stearyl pendant groups.

17.
Soft Matter ; 11(22): 4540-50, 2015 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-25966370

RESUMO

A superhydrophobic surface with anti-icing performance has been the focus of research, but few studies have reported the effective and low cost strategy that met the requirements under overcooled conditions. In this article, the fluorinated sol-gel colloid coatings were simply prepared via hydrolytic condensation of nanosilica sol, methyltriethoxysilane (MTES) and 3-[(perfluorohexylsulfonyl)amino]propyltriethoxysilane (HFTES). The multi scale morphology and chemical composition of the artificial surfaces were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). The influence of the surface roughness structure and fluorinated groups on the wettability and freezing delay time of the colloid surface under overcooled conditions were explored. As the HFTES content was higher than 6 wt%, the prepared colloid surface showed excellent superhydropobicity with a contact angle (CA) of about 166° at room temperature. The CA gradually reduced with the decrease of the temperature. Only the samples with high HFTES contents (above 30 wt%) exhibited special superhydrophobic and anti-icing properties under freeze temperature. Besides the surface roughness structure, the high fluoride enrichment on the surface plays a major role in the superhydrophobic and anti-icing properties under overcooled conditions.

18.
Small ; 10(21): 4249-56, 2014 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-25049062

RESUMO

An alkali-assisted cooperative assembly process of two different templating systems with aluminosilicate precursors is described. A highly ordered mesoporous zeolite with the 2D hexagonal symmetry mesospores and MFI zeolitic framework walls is synthesized. This method also allows the preparation of ZSM-5 with c- or b-axis-aligned mesopores. The materials have promising catalytic activities for organic reactions involving bulky molecules.

19.
ACS Appl Bio Mater ; 7(9): 6297-6305, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39221820

RESUMO

Thermal conduction for electronic devices has attracted extensive attention in light of the development of 5G communication. Thermally conductive materials with high thermal conductivity and extensive mechanical flexibility are extremely desirable in practical applications. However, the construction of efficient interconnected conductive pathways and continuous conductive networks is inadequate for either processing or actual usage in existing technologies. In this work, spherical copper nanoparticles (S-CuNPs) and urchin-inspired fractal-growth CuNPs (U-CuNPs), thermally conductive metal fillers induced by ionic liquids, were fabricated successfully through the electrochemical deposition method. Compared to S-CuNPs, the U-CuNPs shows larger specific surface contact area, thus making it easier to build a continuous conductive pathway network in the corresponding U-CuNPs/liquid silicone rubber (LSR) thermally conductive composites. The optimal loading of CuNP fillers was determined by evaluating the rheological performance of the prepolymer and the mechanical properties and thermal conductivity performances of the composites. When the filler loading is 150 phr, the U-CuNPs/LSR produces optimal mechanical properties (e.g., tensile strength and modulus), thermal conductivity (above 1000% improvement compared to pure LSR), and heating/cooling efficiency. The enhanced thermal conductivity of U-CuNPs/LSR was also confirmed through the finite element analysis (FEA) overall temperature distribution, indicating that U-CuNPs with larger specific surface contact areas exhibit more advantages in forming a continuous network in composites than S-CuNPs, making U-CuNPs/LSR a promising and competitive alternative to traditional flexible thermally interface materials.


Assuntos
Cobre , Teste de Materiais , Nanopartículas Metálicas , Tamanho da Partícula , Propriedades de Superfície , Condutividade Térmica , Cobre/química , Nanopartículas Metálicas/química , Fractais , Materiais Biocompatíveis/química
20.
Adv Mater ; 36(9): e2308972, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37917884

RESUMO

Slippery liquid-infused porous surfaces (SLIPS) have received widespread attention in the antifouling field. However, the reduction in antifouling performance caused by lubricant loss limits their application in marine antifouling. Herein, inspired by the skin of a poison dart frog which contains venom glands and mucus, a porous liquid (PL) based on ZIF-8 is prepared as a lubricant and injected into a silicone polyurethane (SPU) matrix to construct a new type of SLIPS for marine antifouling applications: the slippery porous-liquid-infused porous surface (SPIPS). The SPIPS consists of a responsive antifoulant-releasing switch between "defensive" and "offensive" antifouling modes to intelligently enhance the antifouling effect after lubricant loss. The SPIPS can adjust antifouling performance to meet the antifouling requirements under different light conditions. The wastage of antifoulants is reduced, thereby effectively maintaining the durability and service life of SLIPS materials. The SPIPS exhibits efficient lubricant self-replenishment, self-cleaning, anti-protein, anti-bacterial, anti-algal, and self-healing (97.48%) properties. Furthermore, it shows satisfactory 360-day antifouling performance in actual marine fields during boom seasons, demonstrating the longest antifouling lifespan in the field tests of reported SLIPS coatings. Hence, the SPIPS can effectively promote the development of SLIPS for neritic antifouling.


Assuntos
Incrustação Biológica , Animais , Incrustação Biológica/prevenção & controle , Porosidade , Lubrificantes , Rãs Venenosas , Poliuretanos
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