High-performance Nanocomposites Research Articles

The energy-storage density of Polymers/BNBT6 nanocomposites with high breakdown field

Ceramic/polymer dielectric composites show significant potential for energy storage devices in advanced microelectronic applications. However, an excessive quantity of inorganic nanofillers within the polymeric matrix can lead to a substantially unequal distribution of the electric field, which may impede the improvement of energy storage density. Herein, 0.94Bi0.5Na0.5TiO3-0.06BaTiO3 (BNBT6) nanoparticles were synthesized using a combined solid-phase method followed by sieving. The silane coupling agent KH560 was used to modify the nanoparticles. Additionally, polyphenylene oxide (PPO), polytetrafluoroethylene (PTFE), and perfluoroalkyl (PFA) were utilized as matrices. The surface modification enhanced the interfacial coupling interaction between BNBT6 and the polymers, resulting in a lower concentration of interfacial hole defects. The findings demonstrated that BNBT6@KH560/PPO nanocomposites attained a high Wrec (2.71 J cm−³) and an excellent of η ∼ 81.1 % with 50 wt% BNBT6@KH560 nanofiller at 1550 kV cm−1. Furthermore, the exceptional frequency and thermal stability of BNBT6@KH560/PPO nanocomposites made it a strong contender for future portable energy devices. This work presents a feasible solution for synthesizing high-performance dielectric nanocomposites using straightforward preparation techniques.

Synthesis and evaluation of MMT/TiO2 nanotube photocatalysts for enhanced degradation of organic dyes in wastewater

This study aims to synthesize a nanocomposite photocatalyst from naturally sourced clay (montmorillonite, MMT) and titanium dioxide nanotubes (TNTs) to efficiently degrade organic dyes in wastewater under UVC light. The TNTs were synthesized through the hydrothermal method and were randomly attached to both the surface and interlayer spaces of the MMT sheets. Pristine MMT was found to exhibit good adsorption properties, while the TNTs demonstrated strong photocatalytic activity. The combination of these materials in the MMT/TNT nanocomposite resulted in a material that exhibited both adsorption and photocatalytic properties. The dye degradation efficiency of the MMT/TNT nanocomposite reached 95%, which is significantly higher than that of pristine MMT (50%) and TNTs alone (60%). This enhanced performance can be attributed to the synergistic effect between the adsorption capacity of MMT and the photocatalytic activity of TNTs. The study highlights the potential of using naturally sourced materials like MMT in the development of advanced photocatalysts for environmental remediation. The MMT/TNT nanocomposite offers a sustainable and efficient solution for the removal of organic pollutants from wastewater. These findings provide a pathway for further development of high-performance nanocomposites that combine the dual functional properties of adsorption and photocatalysis, contributing to more efficient wastewater treatment technologies.

Synthesis and Fabrication of Metal Cation Intercalation in Multilayered Ti3C2Tx Composite CNF Electrode for Asymmetric Coin Cell Supercapacitors.

Ti3C2Tx has attracted considerable attention from researchers in energy storage due to its unique structure and beneficial surface functional group characteristics. Recent studies have focused extensively on developing Ti3C2Tx composites to create potential electrode materials for energy storage applications. Carbon nanofiber is often combined with Ti3C2Tx to produce high-performance functional nanocomposites, effectively harnessing the unique properties of Ti3C2Tx nanosheets while ensuring exceptional electrochemical behavior. This work employs an ultrasonication method to prepare a Na-Ti3C2Tx/CNF electrode. Establishing a stable interlayer structure between Ti3C2Tx nanosheets and cationic metal intercalation materials is crucial for expanding the interlayer spacing of Ti3C2Tx and creating multidirectional stable ion transport channels. Consequently, this process exposes more active sites that are accessible to ions. At a current density of 1 A g-1, the resulting Na-Ti3C2Tx/CNF demonstrates an impressive specific capacitance of 680.2 F g-1. Notably, the asymmetric supercapacitor assembled with Na-Ti3C2Tx/CNF as the positive electrode and activated carbon as the negative electrode exhibits remarkable cyclic retention of 83.1% and the Coulombic efficiency of 90.5% after 10,000 cycles at 10 A g-1, a wide voltage window of 1.5 V, a high energy density of 102.5 W h kg-1, and a power density of 2963.7 W kg-1. The fabricated coin cell ASC devices, which include glowing red light-emitting diodes, were demonstrated in practical applications. The optimization strategy for developing Na-Ti3C2Tx/CNF provides essential technical support for integrating Na-Ti3C2Tx/CNF into the next generation of portable and adaptable wearable electrochemical energy storage devices.

Fraction-dependent filler network in silicone rubber: Unraveling abrupt enhancement in rheological properties via solvent extraction and DLS study

A pivotal nanofiller network will be constructed by the filler loading threshold inside the silicone rubber, leading to abrupt enhancement in the rheological properties of the composites. However, the contribution of the nanofiller network to the performance mutation is poorly understood due to lack of direct evidence to recognize the formation of filler networks. This work quantitatively investigated the filler aggregation network of solvent-extracted monodisperse silica-filled polydimethylsiloxane (PDMS) composites to interpret the rheological properties. The results indicated that, when filler loadings reach 60 phr, the size of the filler network reaches its maximum (1280.5 nm), significantly increasing the storage modulus (166 kPa) and Payne effect (163 kPa), due to the formation of a filler network confirmed by Dynamic Light Scattering (DLS) and scanning electron microscope (SEM) observation. The reduction in aggregate size observed with longer extraction times is because of the collapse of the nanofiller network, which occurs as the polymer chains are removed. The aggregates reappear in a monodisperse form as the extraction duration reaches 20 days. This confirms that filler aggregates of interconnected polymer chains can form a well-developed network structure that effectively supports and transfers stresses. This contributes to an in-depth understanding of the formation mechanism of nanofiller networks, aiding the advancement of high-performance polymer nanocomposites.

Modulating interfacial polymerization by combination of organic phase additives and trimesoyl chloride for preparing high-performance thin-film nanocomposite reverse osmosis membranes

Incorporating hydrophilic nanoparticles into organic phase during interfacial polymerization (IP) to establish covalent bonds with organic phase monomers has proven to be a successful approach for fabricating high-performance thin-film nanocomposite (TFN) reverse osmosis (RO) membranes. However, the effect of covalent bonds number on the membrane structure and properties remains uncertain. Herein, hydrochloric acid doped polyaniline (PANI-HCl) with a small amount of amine groups and inherent polyaniline (PANI-base) nanomaterials with a larger amount of amine groups were prepared as organic phase additives for preparing high-performance TFN RO membranes. The amine groups on the nanoparticles can bond covalently with the acyl chloride groups of trimethyl chloride (TMC), leading to the accumulation of TMCs at organic/aqueous interface and accelerates IP reaction rate, resulting in a thinner, denser polyamide layer with more leaf-like structures and free volume. The water permeance of the PANI-base-RO membrane was improved by 62.5 % from 0.8 to 1.3 Lm−2h−1bar−1, and the NaCl rejection was improved from 97.6 % to 99.4 % compared with the pristine membrane. Overall, this work highlights the beneficial impact of organic phase additives with more amine groups on enhancing the desalination performance of RO membranes, providing valuable insights for the structural design of additives and dispersing medium selection.

Facile synthesis of high-performance and self-healing polyurethane-urea nanocomposites reinforced with graphene

In this study, a facile method was employed to synthesize strong, yet highly elastic polyurethane-urea (PUU) with typical characteristics and 94 ​% optical transmittance. Graphene platelets (GNPs) were prepared and modified via a scalable and eco-friendly mechanochemical approach. The produced GNPs is at 1.6-nm thickness with high electrical conductivity of ∼950 ​S/m. The structure-property relations of PUU/GNP nanocomposites were comprehensively investigated through morphology and mechanical properties measurements. The strong interface and high-density hydrogen bonds between modified GNPs (M-GNPs) and PUU significantly enhanced the mechanical properties of the PUU nanocomposite. The PUU composite showed 66.7 ​% and 36.2 ​% increments in tensile and impact strengths, respectively, at 0.2 ​wt% M-GNPs. The reversible hydrogen bond between M-GNPs and PUU endowed the nanocomposite with self-healing properties achieving 97.8 ​% healing efficiency of the strength after 5 ​h at 120 ​°C. This study demonstrates the importance of surface modification and provides a simple yet robust approach for preparing high-performance and functional PUU/graphene composites.

Targeted assembly of hierarchical sea-urchin inspired NiPS@LDH architecture for enhanced toughness, wear-resistance and fire-safety of epoxy composites

Epoxy resin (EP) is a versatile material widely used in fields such as electronic encapsulation, coatings, adhesives, and composites. The targeted assembly of nanomaterials to optimize the flame retardancy, mechanical properties, and interfacial properties of composite materials is a prominent research hotspot in the field of EP. Therefore, a hierarchical sea-urchin inspired architecture (NiPS@LDH), based on layered double hydroxide (LDH) nanosheets grown on nickel phyllosilicate (NiPS), was rationally constructed as a functional filler for EP with a view to building high-performance EP composites. The addition of 1 wt% NiPS@LDH increased the tensile strength, modulus of elasticity, and elongation at break of EP by 44.1 %, 27.6 %, and 66.2 %, respectively, showing excellent strengthening and toughening effects. Meanwhile, under dry friction conditions, the wear rate of the composites was 0.86 mm3·N−1·m−1, reduced by 87.8 % compared to that of pure EP, indicating excellent wear resistance. Besides, the pHRR, THR, pSPR, TSP, pCO and pCO₂ of EP/NiPS@LDH-3 composites were found to be significantly reduced by 54.0 %, 61.9 %, 50.7 %, 54.4 %, 51.2 %, and 58.2 %, respectively. The LOI value of the composites increased to 26.4 %, and the maximum weight loss (Rmax) was reduced by 27.7 %. This study provides an innovative strategy for the targeted assembly of nanomaterials, paving the way for the preparation of high-performance EP nanocomposites.

Enhancing electrical insulation and thermal conductivity in polydimethylsiloxane polymer nanocomposites through silica coating on carbon fibers

Mesophase pitch-based carbon fibers (MPCFs) exhibit high thermal conductivity (∼900Wm−1K−1) and are considered to be an important candidate for future thermal management. However, MPCFs lead to an increase in the electrical conductivity of nanocomposites due to the low volume electrical resistivity (∼10−3 Ω cm). The development of MPCFs nanocomposites with high thermal conductivity and good electrical insulation remains a challenging problem. In order to solve the problem, we utilized the surfactant cetyltrimethylammonium bromide (CTAB) as an anchor for hydrolysis, and employed a sol-gel method to deposit a silica coating on MPCFs (silica@MPCFs). Silica@MPCFs was used as the filler for polydimethylsiloxane (PDMS) matrix. The nanocomposites exhibit commendable thermal conductivity (achieving 1.52 Wm−1K−1) and excellent volume electrical insulation (exceeding 1013 Ω cm) at a 30 vol% concentration. Notably, both the thermal conductivity and volume electrical insulation exceed MPCFs/PDMS. This approach to electrical insulation treatment holds substantial potential for the future preparation of high-performance nanocomposites of electronic devices.

High-performance thermoplastic nanocomposites for aerospace applications: A review of synthesis, production, and analysis

Thermoset polymers are cured under natural or synthetic created conditions and retain their solid form when exposed to heat. Unlike thermosets, thermoplastics melt when exposed to heat after production. Thermoplastics are preferred as raw materials because they can be easily shaped after production, have a high shelf life and are recyclable. In this regard, the prominence of high-performance engineering polymers in recent years has led to the preference of alternative polymers to thermosets. High-performance engineering thermoplastics include thermoplastics such as polyphenylene-sulfide (PPS), polyether-ether-ketone (PEEK), polyether-ketone-ketone (PEKK), polyphenylene-ether, polysulfone,polyoxadiazole, polyimide, polyether-amide, polyether-amide-imide, polynaphthalene, and polyamide-imide. These polymers exhibit application potential in aerospace, defense, automotive, marine, energy, and medical sectors. In challenging conditions such as high pressure, temperature, and corrosive environments, they possess high service temperatures, enhanced mechanical and physical properties, preferable chemical resistance as well as out-of-autoclave and rapid processing properties. In this review article, nanomaterial production methods (bottom-up and top-bottom) are mentioned. In the following sections, PPS, PEEK, and PEKK thermoplastics are explained, and carbon- and boron-based nano additives used in constructing nanocomposites are investigated. In the last section, PPS, PEKK, and PEEK polymer nanocomposites are investigated.

Preparation of High-Performance Polyethylene Nanocomposites with Oleic Acid-Siloxene-Supported Ziegler-Natta Catalysts.

The addition of two-dimensional inorganic nanomaterials can effectively enhance the properties of polyethylene (PE). In the present study, a series of high-performance PE/oleic acid (OA)-siloxene nanocomposites were prepared by in situ polymerization using OA-siloxene-supported Ziegler-Natta catalysts. Compared with the conventional Ziegler-Natta catalyst, the polymerization activity of the OA-siloxene-supported Ziegler-Natta catalyst was enhanced to 100 kg/mol-Ti•h, an increase of 56%. The OA-siloxene fillers exhibited excellent dispersion within the PE matrix through the in situ polymerization technique. Compared to pure PE, PE/OA-siloxene nanocomposites containing 1.13 wt% content of OA-siloxene showed 68.3 °C, 126%, 37%, and 46% enhancements in Tdmax, breaking strength, modulus, and elongation at break, respectively.

Versatile fabrication of palygorskite/diene-based rubber nanocomposites via autogenous-modification and sulfur co-vulcanization strategy

The dispersion and stability of nanofillers in polymer matrices are the main challenges in polymer nanocomposites, especially the rubber nanocomposites. Here, autogenous-modification of nanofillers was proposed for a good dispersion, and therefore a good stability could be achieved via sulfur co-vulcanization with rubber matrix. With the palygorskite (Pal)/nitrile-butadiene rubber (NBR) nanocomposite as an example, NBR chains could be introduced onto the Pal nanorods via surface cross-metathesis reaction, and then the resultant NBR grafted Pal nanorods (NBR-Pal) could be co-vulcanized with NBR matrix. The incorporation of the Pal nanorods in the crosslinked network was revealed by the X-ray photoelectron spectroscopy (XPS) analysis after de-vulcanization. The proposed strategy is expected to impel the mass production and practical application of high-performance diene-based rubber nanocomposites.

Highly Regular Layered Structure via Dual-Spatially-Confined Alignment of Nanosheets Enables High-Performance Nanocomposites.

Assembling ultrathin nanosheets into layered structure represents one promising way to fabricate high-performance nanocomposites. However, how to minimize the internal defects of the layered assemblies to fully exploit the intrinsic mechanical superiority of nanosheets remains challenging. Here, a dual-scale spatially confined strategy for the co-assembly of ultrathin nanosheets with different aspect ratios into a near-perfect layered structure is developed. Large-aspect-ratio (LAR) nanosheets are aligned due to the microscale confined space of a flat microfluidic channel, small-aspect-ratio (SAR) nanosheets are aligned due to the nanoscale confined space between adjacent LAR nanosheets. During this co-assembly process, SAR nanosheets can flatten LAR nanosheets, thus reducing wrinkles and pores of the assemblies. Benefiting from the precise alignment (orientation degree of 90.74%) of different-sized nanosheets, efficient stress transfer between nanosheets and interlayer matrix is achieved, resulting in layered nanocomposites with multiscale mechanical enhancement and superior fatigue durability (100000 bending cycles). The proposed co-assembly strategy can be used to orderly integrate high-quality nanosheets with different sizes or diverse functions toward high-performance or multifunctional nanocomposites.

Dispersion Strategy improves the mechanical properties of 3D-Printed biopolymer nanocomposite

Homogenous dispersion of nanoparticles in polymer matrices is a technical challenge that if overcome can lead to improved mechanical properties of the resulting nanocomposites. In this work, we successfully refined commercially-available nanoscale, calcium deficient, and poorly crystalline hydroxyapatite (nHA) particles and composited them with acrylate and methacrylate functionalized soybean oil (mAESO) and triethylene glycol dimethacrylate (TEGDMA) producing inks for masked stereolithography (mSLA) -based 3D printing. First, we used shear mixing and ultrasonication on nHA/ethanol mixtures to break down agglomerates and then separated the finest nanoparticles from the remaining agglomerates using centrifugation. The refined nanoparticles (termed fine) were then mixed with the resins and UV-initiator to produce inks for 3D printing. Similarly, we prepared one ink using as-purchased nHA particles (termed raw) and another ink using leftover agglomerates after refinement (termed coarse). We compared the rheological properties of the nHA-resin inks. We used mSLA to fabricate nanocomposite specimens and tested them using flexural, and Mode-I fracture toughness testing following ASTM standards. The dispersion of nanoparticles in the polymer matrix was studied by analyzing backscattered mode scanning electron microscopy images. The nHA particle refinement improved the nanoparticle dispersion in the resin matrix while also increasing the viscosity and shear yield strength of the nanocomposite ink. The flexural fracture strength, flexural modulus, and Mode-I fracture toughness of refined nHA-based nanocomposites were increased by 11 %, 71 %, and 12 %, respectively compared to the raw nHA-based nanocomposites. However, the flexural fracture strain of refined nHA-based nanocomposites was lower by 40 % compared to the raw nHA-based nanocomposites. The nanocomposites became stiffer with the incorporation of refined nanoscale nHA. The separation of nanoscale nHA particles, excellent dispersion of these nanoparticles in polymer matrix, and improved flexural strength and modulus opens a new avenue towards the 3D printing of high-performance nHA-based nanocomposites.

Photopolymerization Approach to Advanced Polymer Composites: Integration of Surface-Modified Nanofillers for Enhanced Properties.

The incorporation of functionalized nanofillers into polymers via photopolymerization approach has gained significant attention in recent years due to the unique properties of the resulting composite materials. Surface modification of nanofillers plays a crucial role in their compatibility and polymerization behavior within the polymer matrix during photopolymerization. This review focuses on the recent developments in surface modification of various nanofillers, enabling their integration into polymer systems through photopolymerization. The review discusses the key aspects of surface modification of nanofillers, including the selection of suitable surface modifiers, such as photoinitiators and polymerizable groups, as well as the optimization of modification conditions to achieve desired surface properties. The influence of surface modification on the interfacial interactions between nanofillers and the polymer matrix is also explored, as it directly impacts the final properties of the nanocomposites. Furthermore, the review highlights the applications of nanocomposites prepared by photopolymerization, such as sensors, gas separation membranes, purification systems, optical devices, and biomedical materials. By providing a comprehensive overview of the surface modification strategies and their impact on the photopolymerization process and the resulting nanocomposite properties, this review aims to inspire new research directions and innovative ideas in the development of high-performance polymer nanocomposites for diverse applications.

Strong and Tough MXene Bridging-induced Conductive Nacre.

Nacre is a classic model, providing an inspiration for fabricating high-performance bulk nanocomposites with the two-dimensional platelets. However, the "brick" of nacre, aragonite platelet, is an ideal building block for making high-performance bulk nanocomposites. Herein, we demonstrated a strong and tough conductive nacre through reassembling aragonite platelets with bridged by MXene nanosheets and hydrogen bonding, not only providing high mechanical properties but also excellent electrical conductivity. The flexural strength and fracture toughness of the obtained conductive nacre reach ~282 MPa and ~6.3 MPa m1/2, which is 1.6 and 1.6 times higher than that of natural nacre, respectively. These properties are attributed to densification and high orientation degree of the conductive nacre, which is effectively induced by the combined interactions of hydrogen bonding and MXene nanosheets bridging. The crack propagations in conductive nacre are effectively inhibited through crack deflection with hydrogen bonding, and MXene nanosheets bridging between aragonite platelets. In addition, our conductive nacre also provides a self-monitoring function for structural damage and offers exceptional electromagnetic interference shielding performance. Our strategy of reassembling the aragonite platelets exfoliated from waste nacre into high-performance artificial nacre, provides an avenue for fabricating high-performance bulk nanocomposites through the sustainable reutilization of shell resources.

Ultrastrong Graphene Sheets Assembled with Nanoconfined Water.

Highly ordered assembly of two-dimensional (2D) nanoplatelets plays a key role in enhancing the mechanical properties of layered nanocomposites. Layer-by-layer (LbL) assembly, vacuum-assisted filtration, and blade coating have been used to fabricate layered nanocomposites. However, the intrinsic wrinkles of 2D nanoplatelets and defects derived from assembling approaches make it difficult to align 2D nanoplatelets. Recently, the team of Prof. Qunfeng Cheng at Beihang University and their collaborator, Prof. Ray H. Baughman at the University of Texas at Dallas developed a novel approach for aligning graphene and Ti3C2Tx MXene nanoplatelets by nanoconfined assembly through continuous vacuum-assisted filtration. The resultant MXene-bridged sheet has ultrastrong mechanical properties and low porosity, providing a new concept for assembling 2D nanoplatelets into aligned and compact high-performance layered nanocomposites.

In Situ Processing to Achieve High-Performance Epoxy Nanocomposites with Low Graphene Oxide Loading

Modifying the polymer matrix by nanoparticles can be a promising approach to improve the performance of fiber-reinforced polymer (FRP) composites. Organic solvents are usually used for dispersing graphene oxide (GO) well in the polymer matrix. In this study, a green, facile, and efficient approach was developed to prepare epoxy/GO nanocomposites. In situ polymerization is used for synthesizing nanocomposites, eliminating the need for organic solvents and surfactants. By loading just 0.6 wt% of GO into the epoxy resin, Young’s modulus, tensile strength, and toughness improved by 38%, 46%, and 143%, respectively. Fractography analysis indicates smooth fracture surfaces of pure resin that changed to highly toughened fracture surfaces in this nanocomposite. Plastic deformation, crack pinning, and deflection contributed to improving the toughness of the nanocomposites. FTIR investigations show that amide bonding was created by the reaction of the carboxylic acid groups in GO with some amine groups in the curing agent during the dispersion processes.

High-performance polymer nanocomposites: advanced fabrication methods and critical insights

High-performance polymer nanocomposites: advanced fabrication methods and critical insights

Morphology and electrical conductivity of carbon-coated Nickel reinforced high-performance polymer nanocomposites

Novel nanocomposites of poly (ether-ketone) (PEK) reinforced with carbon-coated Nickel nanoparticles (CCNi) were synthesized through a sequential process involving cost-effective ball milling and hot compaction. Scanning electron microscopy revealed an excellent dispersion and a three-dimensional network of CCNi nanoparticles in the matrix, causing a significant improvement in the electrical conductivity and electromagnetic interference shielding effectiveness (SE). Carbon coating of about 5 nm thick over Ni nanoparticle probably helps in uniform dispersion, avoids its oxidation and reduces its agglomeration in the matrix. An exceptionally low percolation threshold of 2.1 vol.% CCNi was found, and eight-orders of magnitude enhancement in the dc-electrical conductivity was achieved. The highest dc- and ac-electrical conductivities achieved were more than 0.01 S cm−1 at 5.89 vol.% CCNi nanoparticles content which were the highest values amongst reported Ni-filled polymer composites and comparable with those of carbon nanotubes filled PEK nanocomposites. Electromagnetic interference SE of the CCNi/PEK nanocomposites was measured in the X-band, and a total SE (SET) of 17.52 dB was obtained for 5.89 vol.% CCNi reinforced PEK nanocomposite.

Two birds with one stone: By-product HCl consumption and in-situ template formation for high-performance nanofiltration membranes fabrication

Nanofiltration (NF) membrane with good permselectivity is highly desired. However, it often suffers from permeability-selectivity trade-off in practical applications. To overcome this challenge, a novel in-situ template strategy was proposed for the preparation of high-performance thin film nanocomposite (TFN) NF membrane by adding AgNO3 in the aqueous solution. The AgCl nanoparticles can be in-situ incorporated into the polyamide film due to the by-product of HCl from the interfacial polymerization and AgNO3 at the oil/water interface. Besides, water transportation channels can be further constructed in the polyamide film via removal the AgCl template using ammonia as post-treatment solution. The optimized NF-3 membrane with low water transportation resistance shows a two-fold permeance as well as equal salt rejection compared with the controlled NF-1 membrane, indicating that the “trade-off” effect is effectively inhibited. Consequently, the in-situ template strategy provides a new sight for the preparation of high-performance NF membrane.