The Effect of Polydopamine on an Ag-Coated Polypropylene Nonwoven Fabric

A practical method for preparing multifunctional polypropylene (PP) nonwoven fabrics with excellent stability and durability was explored. First, the PP nonwoven fabric was sputtered by a magnetron sputtering system to form an Ag film on the surface of the fabric. Subsequently, the coated fabric was treated with dopamine. The fabrics were characterized by scanning electron microscopy (SEM), an energy dispersive spectrometer (EDS), electrical conductivity, electromagnetic interference shielding effectiveness (EMI SE), antibacterial activity, stability, and laundering durability. The results of the study revealed that the fabric was coated with Ag, and after the treatment with dopamine, the surfaces of Ag-coated fibers were coated with polydopamine (PDA). The fabrics still had a sheet resistance below ~15 Ω/sq and exhibited excellent EMI SE above ~25 dB, though few differences existed from the single Ag-coated sample. After the treatment with dopamine, the antibacterial activity of the fabric was enhanced. Meanwhile, the treated samples exhibited excellent resistance against sodium sulfide corrosion, which could enhance the stability of the Ag-coated fabric. Moreover, the laundering durability of the treated fabric was improved in the same process, whose lowest sheet resistance was ~18 Ω/sq and the EMI SE was ~8 dB more than single Ag-coated PP nonwoven fabrics. In conclusion, this method was considered to be effective in fabricating multifunctional, stable, and durable fabrics.

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Sheet Resistance of Continuous Filament Nonwoven Fabrics

Journal of Engineered Fibers and Fabrics ◽

10.1177/155892501200700109 ◽

2012 ◽

Vol 7 (1) ◽

pp. 155892501200700

Author(s):

Thomas Godfrey ◽

Benoit Maze ◽

Kris Senecal ◽

Pearl Yip

Keyword(s):

Sheet Resistance ◽

Nonwoven Fabric ◽

Number Density ◽

Electrically Conductive ◽

Nonwoven Fabrics ◽

Modeling Techniques ◽

Continuous Filament ◽

Conduction Behavior ◽

Perfect Bonding ◽

Filament Networks

Two modeling techniques are introduced to predict the sheet resistance of electrically conductive continuous filament nonwoven fabric: a two-dimensional (2–D) discrete filament stochastic resistor network simulation, and a simple analysis using a laminate analogy. The effects of anisotropy and sample size are considered. Results are compared with experiments on a silver coated point bonded nylon nonwoven fabric. For this particular sample, experimental sheet resistance results are significantly under-predicted by the 2–D analytical and simulation approaches where perfect inter-filament bonding is assumed. The utility of the 2–D perfect bonding predictions as an ultimate lower bound on the sheet resistance that may be achieved by extremely well-bonded continuous filament networks is discussed. Simulations of 2–D filament webs with poor inter-filament bonding and moderate anisotropy are shown to agree well with the present experiments. Taken together, the present results suggest that modeling of the in-plane conduction behavior of a general continuous filament nonwoven fabric requires a 3–D structural approach to capture the effect of an appropriate number density of inter-filaments bonds.

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Interface Engineered Microcellular Magnetic Conductive Polyurethane Nanocomposite Foams for Electromagnetic Interference Shielding

Nano-Micro Letters ◽

10.1007/s40820-021-00677-5 ◽

2021 ◽

Vol 13 (1) ◽

Author(s):

Guolong Sang ◽

Pei Xu ◽

Tong Yan ◽

Vignesh Murugadoss ◽

Nithesh Naik ◽

...

Keyword(s):

Electromagnetic Interference ◽

Magnetic Loss ◽

Interfacial Polarization ◽

Conductive Network ◽

Shielding Effectiveness ◽

Electromagnetic Interference Shielding ◽

Multiple Reflections ◽

Conduction Loss ◽

Composite Foams ◽

Emi Se

Abstract Lightweight microcellular polyurethane (TPU)/carbon nanotubes (CNTs)/ nickel-coated CNTs (Ni@CNTs)/polymerizable ionic liquid copolymer (PIL) composite foams are prepared by non-solvent induced phase separation (NIPS). CNTs and Ni@CNTs modified by PIL provide more heterogeneous nucleation sites and inhibit the aggregation and combination of microcellular structure. Compared with TPU/CNTs, the TPU/CNTs/PIL and TPU/CNTs/Ni@CNTs/PIL composite foams with smaller microcellular structures have a high electromagnetic interference shielding effectiveness (EMI SE). The evaporate time regulates the microcellular structure, improves the conductive network of composite foams and reduces the microcellular size, which strengthens the multiple reflections of electromagnetic wave. The TPU/10CNTs/10Ni@CNTs/PIL foam exhibits slightly higher SE values (69.9 dB) compared with TPU/20CNTs/PIL foam (53.3 dB). The highest specific EMI SE of TPU/20CNTs/PIL and TPU/10CNTs/10Ni@CNTs/PIL reaches up to 187.2 and 211.5 dB/(g cm−3), respectively. The polarization losses caused by interfacial polarization between TPU substrates and conductive fillers, conduction loss caused by conductive network of fillers and magnetic loss caused by Ni@CNT synergistically attenuate the microwave energy.

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A Textile Waste Fiber-Reinforced Cement Composite: Comparison between Short Random Fiber and Textile Reinforcement

Materials ◽

10.3390/ma14133742 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3742

Author(s):

Payam Sadrolodabaee ◽

Josep Claramunt ◽

Mònica Ardanuy ◽

Albert de la Fuente

Keyword(s):

Construction Material ◽

Drying Shrinkage ◽

Cement Composite ◽

Nonwoven Fabric ◽

Textile Waste ◽

Nonwoven Fabrics ◽

Potential Applications ◽

Reinforced Cement ◽

The One ◽

Garment And Textile

Currently, millions of tons of textile waste from the garment and textile industries are generated worldwide each year. As a promising option in terms of sustainability, textile waste fibers could be used as internal reinforcement of cement-based composites by enhancing ductility and decreasing crack propagation. To this end, two extensive experimental programs were carried out, involving the use of either fractions of short random fibers at 6–10% by weight or nonwoven fabrics in 3–7 laminate layers in the textile waste-reinforcement of cement, and the mechanical and durability properties of the resulting composites were characterized. Flexural resistance in pre- and post-crack, toughness, and stiffness of the resulting composites were assessed in addition to unrestrained drying shrinkage testing. The results obtained from those programs were analyzed and compared to identify the optimal composite and potential applications. Based on the results of experimental analysis, the feasibility of using this textile waste composite as a potential construction material in nonstructural concrete structures such as facade cladding, raised floors, and pavements was confirmed. The optimal composite was proven to be the one reinforced with six layers of nonwoven fabric, with a flexural strength of 15.5 MPa and a toughness of 9.7 kJ/m2.

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Ultrathin, Lightweight, and Flexible CNT Buckypaper Enhanced Using MXenes for Electromagnetic Interference Shielding

Nano-Micro Letters ◽

10.1007/s40820-021-00597-4 ◽

2021 ◽

Vol 13 (1) ◽

Author(s):

Rongliang Yang ◽

Xuchun Gui ◽

Li Yao ◽

Qingmei Hu ◽

Leilei Yang ◽

...

Keyword(s):

Electromagnetic Interference ◽

High Performance ◽

Electronic Devices ◽

Deposition Process ◽

Shielding Effectiveness ◽

Emi Shielding ◽

Emi Shielding Effectiveness ◽

X Band ◽

Wearable Electronic Devices ◽

Emi Se

AbstractLightweight, flexibility, and low thickness are urgent requirements for next-generation high-performance electromagnetic interference (EMI) shielding materials for catering to the demand for smart and wearable electronic devices. Although several efforts have focused on constructing porous and flexible conductive films or aerogels, few studies have achieved a balance in terms of density, thickness, flexibility, and EMI shielding effectiveness (SE). Herein, an ultrathin, lightweight, and flexible carbon nanotube (CNT) buckypaper enhanced using MXenes (Ti3C2Tx) for high-performance EMI shielding is synthesized through a facile electrophoretic deposition process. The obtained Ti3C2Tx@CNT hybrid buckypaper exhibits an outstanding EMI SE of 60.5 dB in the X-band at 100 μm. The hybrid buckypaper with an MXene content of 49.4 wt% exhibits an EMI SE of 50.4 dB in the X-band with a thickness of only 15 μm, which is 105% higher than that of pristine CNT buckypaper. Furthermore, an average specific SE value of 5.7 × 104 dB cm2 g−1 is exhibited in the 5-μm hybrid buckypaper. Thus, this assembly process proves promising for the construction of ultrathin, flexible, and high-performance EMI shielding films for application in electronic devices and wireless communications.

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A Healable and Mechanically Enhanced Composite with Segregated Conductive Network Structure for High-Efficient Electromagnetic Interference Shielding

Nano-Micro Letters ◽

10.1007/s40820-021-00693-5 ◽

2021 ◽

Vol 13 (1) ◽

Author(s):

Ting Wang ◽

Wei-Wei Kong ◽

Wan-Cheng Yu ◽

Jie-Feng Gao ◽

Kun Dai ◽

...

Keyword(s):

Electromagnetic Interference ◽

Diels Alder ◽

Electrostatic Attraction ◽

List Type ◽

Shielding Effectiveness ◽

Emi Shielding ◽

Electromagnetic Interference Shielding ◽

Elongation At Break ◽

High Efficient ◽

Emi Se

Highlights The cationic waterborne polyurethanes microspheres with Diels-Alder bonds were synthesized for the first time. The electrostatic attraction not only endows the composite with segregated structure to gain high electromagnetic-interference shielding effectiveness, but also greatly enhances mechanical properties. Efficient healing property was realized under heating environment. Abstract It is still challenging for conductive polymer composite-based electromagnetic interference (EMI) shielding materials to achieve long-term stability while maintaining high EMI shielding effectiveness (EMI SE), especially undergoing external mechanical stimuli, such as scratches or large deformations. Herein, an electrostatic assembly strategy is adopted to design a healable and segregated carbon nanotube (CNT)/graphene oxide (GO)/polyurethane (PU) composite with excellent and reliable EMI SE, even bearing complex mechanical condition. The negatively charged CNT/GO hybrid is facilely adsorbed on the surface of positively charged PU microsphere to motivate formation of segregated conductive networks in CNT/GO/PU composite, establishing a high EMI SE of 52.7 dB at only 10 wt% CNT/GO loading. The Diels–Alder bonds in PU microsphere endow the CNT/GO/PU composite suffering three cutting/healing cycles with EMI SE retention up to 90%. Additionally, the electrostatic attraction between CNT/GO hybrid and PU microsphere helps to strong interfacial bonding in the composite, resulting in high tensile strength of 43.1 MPa and elongation at break of 626%. The healing efficiency of elongation at break achieves 95% when the composite endured three cutting/healing cycles. This work demonstrates a novel strategy for developing segregated EMI shielding composite with healable features and excellent mechanical performance and shows great potential in the durable and high precision electrical instruments.

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Electrically conductive and electromagnetic interference shielding of polyethylene composites with devisable carbon nanotube networks

Journal of Materials Chemistry C ◽

10.1039/c5tc01822f ◽

2015 ◽

Vol 3 (36) ◽

pp. 9369-9378 ◽

Cited By ~ 147

Author(s):

Li-Chuan Jia ◽

Ding-Xiang Yan ◽

Cheng-Hua Cui ◽

Xin Jiang ◽

Xu Ji ◽

...

Keyword(s):

Carbon Nanotube ◽

Electromagnetic Interference ◽

Electromagnetic Interference Shielding ◽

Electrically Conductive ◽

Carbon Nanotube Networks ◽

Emi Se ◽

Segregated Structure ◽

Polyethylene Composites

A segregated structure results in an EMI SE up to 46.4 dB in CNT/polyethylene composites with only 5 wt% CNTs.

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Electromagnetic interference shielding effectiveness of polypyrrole-silver nanocomposite films on silane-modified flexible sheet

High Performance Polymers ◽

10.1177/09540083211064535 ◽

2021 ◽

pp. 095400832110645

Author(s):

Karim Benzaoui ◽

Achour Ales ◽

Ahmed Mekki ◽

Abdelhalim Zaoui ◽

Boudjemaa Bouaouina ◽

...

Keyword(s):

Surface Treatment ◽

Electromagnetic Interference ◽

Nanocomposite Films ◽

Electrical Characteristics ◽

Shielding Effectiveness ◽

Emi Shielding ◽

Electromagnetic Interference Shielding ◽

Silver Nanocomposite ◽

Electromagnetic Interference Shielding Effectiveness ◽

Emi Se

The conventional electromagnetic interference (EMI) shielding materials are being gradually replaced by a new generation of supported conducting polymer composites (CPC) films due to their many advantages. This work presents a contribution on the effects of silane surface–modified flexible polypyrrole-silver nanocomposite films on the electromagnetic interference shielding effectiveness (EMI-SE). Thus, the UV-polymerization was used to in-situ deposit the PPy-Ag on the biaxial oriented polyethylene terephthalate (BOPET) flexible substrates whose surfaces were treated by 3-aminopropyltrimethoxysilane (APTMS). X-ray Photoelectron Spectroscopy (XPS) analyzes confirmed the APTMS grafting procedure. Structural, morphological, thermal, and electrical characteristics of the prepared films were correlated to the effect of substrate surface treatment. Thereafter, EMI-SE measurements of the elaborated films were carried out as per ASTM D4935 standard for a wide frequency band extending from 50 MHz to 18 GHz. The obtained results confirmed that the APTMS-treated BOPET film exhibit higher EMI shielding performance and better electrical characteristics compared to the untreated film. In fact, a 32% enhancement of EMI-SE was noted for the treated films compared to the untreated ones. Overall, these results put forward the role played by the surface treatment in strengthening the position of flexible PPy-Ag supported films as high-performance materials in electronic devices and electromagnetic interference shielding applications.

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A green in situ synthesis of silver nanoparticles on cotton fabrics using Aloe vera leaf extraction for durable ultraviolet protection and antibacterial activity

Textile Research Journal ◽

10.1177/0040517516671124 ◽

2016 ◽

Vol 87 (19) ◽

pp. 2407-2419 ◽

Cited By ~ 17

Author(s):

Qingqing Zhou ◽

Jingchun Lv ◽

Yu Ren ◽

Jiayi Chen ◽

Dawei Gao ◽

...

Keyword(s):

Silver Nanoparticles ◽

Antibacterial Activity ◽

Aloe Vera ◽

Cotton Fabrics ◽

In Situ Synthesis ◽

Uv Protection ◽

X Ray ◽

Jcpds File ◽

Laundering Durability

This study presented a simple and environmentally friendly method of in situ synthesis of silver nanoparticles (AgNPs) on cotton fabrics for durable ultraviolet (UV) protection and antibacterial activity using Aloe vera leaf extraction (AVE) as a reducing and stabilizing agent. Cotton fabrics were pretreated in water, and then immersed in AgNO3 and AVE, respectively. Cotton fabrics were characterized by small angle X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis, UV protection, antibacterial activity, and laundering durability. Comparing with the smooth surface of the control cotton fabric, SEM and energy dispersive X-ray spectrometry (EDX) results showed that there were a considerable number of Ag2O and AgNPs loading on the surface of the pretreated and Ag loaded cotton fabrics. The XRD pattern indicated, respectively, the existence of Ag2O and AgNPs, the structures of which were similar to JCPDS File No.65-3289 and JCPDS File No. 01-071-4613 on the pretreated and Ag loaded cotton fabrics. The pretreated and Ag loaded cotton fabrics showed excellent UV protection, antibacterial activity, and laundering durability, especially the Ag loaded cotton fabric, of which the UV protection factor value and transmission of UVA were 148 and 1.11%, respectively, after 20 washing cycles, and the clear zone width was more than 4 mm against E. coli or S. aureus. AgNPs facilitated the improvement of the thermal property of the cotton fabrics. Thus this facile in situ reduction of AgNPs with AVE may bring a promising and green strategy to produce functional textiles.

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A Study on the Entanglement and High-Strength Mechanism of Spunlaced Nonwoven Fabric of Hydrophilic PET Fibers

Journal of Engineered Fibers and Fabrics ◽

10.1177/155892501300800415 ◽

2013 ◽

Vol 8 (4) ◽

pp. 155892501300800 ◽

Cited By ~ 2

Author(s):

Hong Wang ◽

Jingjing Zhu ◽

Xiangyu Jin ◽

Haibo Wu

Keyword(s):

Tensile Strength ◽

High Strength ◽

Nonwoven Fabric ◽

Fiber Content ◽

Nonwoven Fabrics ◽

Pull Out ◽

Fundamental Research ◽

Pet Fibers ◽

Set Up

Spunlaced nonwoven fabrics have been widely used recently, but fundamental research on the spunlaced nonwoven process is relatively weak. It is inexplicit until now how fibers are entangled with each other during the hydroentangling process. In this paper, a pull-out experiment designed to study the entanglement properties of spunlaced nonwoven fabrics using common and hydrophilic PET fibers as objects is described. It was found that the broken fiber content can be used to represent the entanglement intensity of the spunlaced nonwoven fabrics. In addition, a formula was set up to calculate the tensile strength of the spunlaced nonwoven fabric based on its pull-out behavior.

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Robust Design of PC/ABS Filled with Nano Carbon Black for Electromagnetic Shielding Effectiveness and Surface Resistivity

Processes ◽

10.3390/pr8050616 ◽

2020 ◽

Vol 8 (5) ◽

pp. 616

Author(s):

Wipoo Sriseubsai ◽

Arsarin Tippayakraisorn ◽

Jun Wei Lim

Keyword(s):

Carbon Black ◽

Electromagnetic Interference ◽

Electrostatic Discharge ◽

Acrylonitrile Butadiene Styrene ◽

Surface Resistivity ◽

Shielding Effectiveness ◽

Electromagnetic Interference Shielding Effectiveness ◽

Electromagnetic Shielding Effectiveness ◽

Emi Se ◽

Butadiene Styrene

This study focuses on the electromagnetic interference shielding effectiveness (EMI SE), dissipation of electrostatic discharge (ESD), and surface resistivity of polymer blends between polycarbonate (PC) and acrylonitrile–butadiene–styrene (ABS) filled with carbon black powder (CBp) and carbon black masterbatch (CBm). The mixtures of PC/ABS/CB composites were prepared by the injection molding for the 4-mm thickness of the specimen. The D-optimal mixture design was applied in this experiment. The EMI SE was measured at the frequency of 800 and 900 MHz with a network analyzer, MIL-STD-285. The result showed that the EMI SE was increased when the amount of filler increased. The surface resistivity of the composites was determined according to the ASTM D257. It was found that the surface resistivity of the plastic with no additives was 1012 Ω/ square. When the amount of fillers was added, the surface resistivity of plastic composites decreased to the range of 106–1011 Ω/square, which was suitable for the application without the electrostatic discharge. The optimization of multi-response showed using high amounts of PC and CB was the best mixture of this research.

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