Hybrid Polymer Nanocomposites Research Articles

Physical and Mechanical Characterization of Bamboo Fiber/Groundnut Shell/Copper Particle/MWCNT‐Filled Epoxy Hybrid Polymer Nanocomposites

Current research finds the suitability of natural fiber‐reinforced polymer composites for industrial, automotive, marine, aerospace, and military vehicle applications, among others; they process being lightweight, high strength, ecofriendly, recyclable, and biodegradable. Bamboo fiber (Bambusoideae) mat, groundnut shell (Cocos nucifera) powder, copper particle, and multiwalled carbon nanotubes (MWCNT) fillers with epoxy resin are the primary materials. The key responsibility of MWCNT as a nanofiller is to improve the performance of materials by more than 80% and to attract the desirable properties such as high specific energy absorption of CNTs. An extensive investigation was carried out to determine the weight ratio between the total density and the water absorption rate of the composite. The maximal tensile and flexural strengths derived from EBGCM2 (E: epoxy; B: bamboo; G: groundnut shell; C: copper particle; M: MWCNT) were 50.66 MPa and 59.03 MPa, respectively. Addition of MWCNTs to specimens EBGCM2 and EBGCM3 and bonding the filler matrix by homogeneous mixing, but few nanoparticles are seen agglomerated. Flexural abilities of groundnut fiber/filler loading to strengthen the hybrid nanocomposites and the impact strength both quite improved than EB1 specimen. The neat epoxy and bamboo fiber composite (EB1) achieved 87.5 Shore‐D hardness. SEM revealed (EBGCM3) improved interfacial adhesion between fiber and epoxy resin, but few nanoparticles are agglomerated, small molecules linked between the fibrous matrix, and the binding elements trapped in neighboring atoms, forming structural chains by the polymerization process.

BENDING PROPERTIES OF A FUNCTIONALLY GRADED POLYMERIC COMPOSITE REINFORCED WITH A HYBRID NANOMATERIAL

In this paper, functionally graded polymer hybrid nanocomposites have been produced by silica (SiO2) nanoparticles and alumina (Al2O3) nanoparticles distributed in a matrix of epoxy during the ultra-sonication via hand lay-up method. The variation in nanoparticles volume fraction (Vf.) has been given in the thickness direction for reaching the gradation. Each layer has a thickness of 1.2 mm through various concentrations of nanoparticles and is sequentially cast in acrylic moulds to fabricate the graded composite sheet with a 6 mm thickness. To fabricate the functionally graded layers, various concentrations of different nanoparticles (1.5% SiO2, 1% SiO2, epoxy, 2% Al2O3 and 3% Al2O3) have been used for tensile and compressive testing each isotropic layer of functionally graded material (FGM). The mechanical property that was studied for pure epoxy, isotropic and FGM was the flexural resistance. The flexural properties of FGM, isotropic nanocomposite (1% SiO2 + 2% Al2O3) and pristine epoxy, for evaluating their mechanical properties, including flexural stress-strain criteria and flexural Young's modulus, were determined via a Three-point bending test, with loading from the side of silica and alumina for the hybrid-FGM and at one side for the isotropic hybrid nanocomposite and pristine epoxy. The mechanical properties (tensile and compression) and the density of every layer were obtained for the epoxy resin and nanocomposites. They can benefit from the Finite Element Analysis (FEA) of the Three-point bending test via the Design Modeler (ANSYS workbench). The results of experiments were confirmed via building a detailed 3D FE model. Also, the advanced deformation results from the FE model were found in good agreement with the experimental outcomes.

Structure – properties relationships of graphene and spinel nickel ferrites based poly(vinylidene fluoride) hybrid polymer nanocomposites for improved dielectric and EMI shielding characteristics

Hybrid polymer nanocomposites with poly(vinylidene fluoride) are prepared based on graphene and spinel nickel ferrites (nFE) nanoparticles to investigate their structure-properties relationships. X-ray diffraction and differential scanning calorimetry confirmed the co-existence of α- and β-crystal phases of PVDF by the incorporation of graphene and nFE whereas solely α- crystal phase formed in neat PVDF. The influence of graphene and nFE on the mechanical properties of PVDF is concentration dependant. The modulus of PVDF is enhanced ∼ 128% from 587 to 1340 MPa at the expense of reduction in failure strain from 18% to 6% in PVDF/graphene nanocomposite whereas in PVDF/graphene/nFE hybrid nanocomposites, the mechanical properties are reduced owing to the embrittlement. On the contrary, graphene-nFE-polymer interfacial space charge accumulation has caused the enhancement of dielectric and EMI shielding characteristics as a function of frequency (1kHz-5 MHz). In PVDF/graphene nanocomposites at 3 wt%, the dielectric constant (ε/) value is increased 16-fold while keeping the dielectric loss (ε//) values equivalent to neat PVDF. Whereas, both ε/ and ε// are increased enormously in PVDF/graphene/nFE hybrid nanocomposites along the whole frequency range. Similarly, EMI shielding (SET) of PVDF/graphene and PVDF/graphene/nFE is ∼ 16 and 22 dB, respectively for a film thickness of ∼0.2 mm. Comparatively, PVDF/graphene nanocomposites exhibited the synergistic balance in mechanical, dielectric and EMI shielding properties over PVDF/graphene/nFE hybrid nanocomposites.

Flexible, stretchable and electrically conductive PDMS decorated with polypyrrole/manganese-iron oxide nanocomposite as a multifunctional material for high performance EMI shielding applications

Rapid growth in portable and wearable electronics requires high performance electromagnetic shielding materials that are lightweight, flexible, stretchable and electrically conductive to counter the problems of increasing electromagnetic pollutions. Absorption dominant microwave wrap-on shielding materials are in great demand for mitigating the effect of electromagnetic interference on devices and the environment. In this work we report preparation of a multifunctional composite that effectively combines the outstanding EMI shielding, electrical conductivity mechanical flexibility and magnetic properties of hybrid polymer nanocomposite systems for wearable electronics. Highly conductive Polypyrrole (PPy)/Manganese-Iron oxide (MnFe2O4) nanocomposites treated with para toluene sulphonic acid (PTSA) were incorporated into polydimethylsiloxane (PDMS) matrix to obtain a multifunctional hybrid structure. The incorporation of PTSA treated PPy- MnFe2O4 nanoparticles forms excellent conductive network and improves the electrical and magnetic properties of the composites. The PDMS based nanocomposite exhibit superior conductivity of 24.03 S/cm with robust mechanical properties such as Young’s modulus (0.93 MPa) and tensile strength (2.62 MPa). Due to improved conductivity and magnetic attributes this PDMS based nanocomposite with 0.5 mm thickness shows absorption dominated superior electromagnetic shielding performance (EMI-SE of −21 dB corresponds to 99.21% of shielding efficiency) in X-band microwave frequencies. Further, these nanocomposite shields exhibit excellent stability in conductivity and EMI-SE values under mechanical stretching and bending. Apart from being an excellent shielding material, this PDMS based nanocomposite serves as a superior strain sensor, indicates multifunctional dimensions of this material. Owing to the features such as light weight, flexibility, stretchability, high conductivity, excellent EMI-SE as and superior strain sensing performance, these composites can be used in flexible and foldable devices as smart wrap-on shield.

Experimental investigation of shape memory polymer hybrid nanocomposites modified by carbon fiber reinforced multi-walled carbon nanotube (MWCNT)

This paper presents the effect of the variations of multi-walled carbon nanotube (MWCNT) modification in shape memory polymer hybrid composites concerning their mechanical, thermomechanical, and shape memory characterizations. The process of fabrication includes preparation of the MWCNT/epoxy hybrid nanocomposites by shear mixing, ultrasonication, magnetic stirring, and subsequent molding by hand layup method. The appropriate post-processing was performed for the curing and cutting to prepare the samples for the mechanical and thermomechanical characterizations as per the ASTM standards. An enhancement in the thermomechanical properties was noticed due to the incorporation of the MWCNT. These observations were also validated with improvement in the interfacial bonding between the carbon fiber and the modified matrix, as shown in the morphological fractography. The tensile strengths were improved by 18%, 39%, and 26% with the incorporation of 0.4%, 0.6%, and 0.8% modified MWCNT nanocomposites as compared to pure unmodified SMPC. However, the shape recovery of all the configurations of the shape memory polymer hybrid composites was not compromised on polymer-modified remaining almost unchanged at 94%.

Emerging MXene-Polymer Hybrid Nanocomposites for High-Performance Ammonia Sensing and Monitoring.

Ammonia (NH3) is a vital compound in diversified fields, including agriculture, automotive, chemical, food processing, hydrogen production and storage, and biomedical applications. Its extensive industrial use and emission have emerged hazardous to the ecosystem and have raised global public health concerns for monitoring NH3 emissions and implementing proper safety strategies. These facts created emergent demand for translational and sustainable approaches to design efficient, affordable, and high-performance compact NH3 sensors. Commercially available NH3 sensors possess three major bottlenecks: poor selectivity, low concentration detection, and room-temperature operation. State-of-the-art NH3 sensors are scaling up using advanced nano-systems possessing rapid, selective, efficient, and enhanced detection to overcome these challenges. MXene–polymer nanocomposites (MXP-NCs) are emerging as advanced nanomaterials of choice for NH3 sensing owing to their affordability, excellent conductivity, mechanical flexibility, scalable production, rich surface functionalities, and tunable morphology. The MXP-NCs have demonstrated high performance to develop next-generation intelligent NH3 sensors in agricultural, industrial, and biomedical applications. However, their excellent NH3-sensing features are not articulated in the form of a review. This comprehensive review summarizes state-of-the-art MXP-NCs fabrication techniques, optimization of desired properties, enhanced sensing characteristics, and applications to detect airborne NH3. Furthermore, an overview of challenges, possible solutions, and prospects associated with MXP-NCs is discussed.

Broadband Radio Frequency Dielectric Permittivity and Electrical Conductivity of Dispersed Tin Oxide and Silica Nanoparticles in Poly(Ethylene Oxide)/Poly(Methyl Methacrylate) Blend Matrix-Based Nanocomposites for Nanodielectric Applications

In regards to the advances in hybrid polymer nanocomposite (HPNC) materials for high-frequency nanodielectric applications, herein we report the broadband radio frequency range (1 MHz to 1 GHz) dielectric permittivity and electrical conductivity of composites of poly(ethylene oxide) (PEO)/poly(methyl methacrylate) (PMMA) blend matrices and oxide nanofillers (tin oxide (SnO2) and silica (SiO2)), in the form of PEO/PMMA/SnO2 and PEO/PMMA/SiO2 films at ambient temperature. The results confirmed that these HPNCs have low dielectric permittivity values which decrease slightly, from 3.4 to 2.8, with increasing nanofillers concentrations and the applied electric field frequency. The dependency of the dielectric permittivity on the different oxide nanoparticles sizes and their dielectric constant was explored. The dielectric loss tangent spectra of these hybrid materials indicated that they were reasonably low loss nanodielectrics having a dipolar orientation relaxation in the higher frequency region. The radiofrequency electrical conductivity of the HPNCs was found to increase linearly from ∼10−8 to 10−4 S/cm with the increase of frequency, and it was less dependent on the fillers concentrations. Considering the dielectric and electrical properties, it is proposed that these PEO/PMMA/SnO2 and PEO/PMMA/SiO2 composites could be highly useful materials for dielectric substrates and insulators in the development of radiofrequency operative flexible-type electrical and electronic components and devices.

Structure, optical and photoluminescent properties of hybrid polymer nanocomposites on the base PP+CdS/ZnS

In this work, PP+CdS/ZnS transparent hybrid polymer nanocomposites were synthesized and studied. The nanocomposites were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive (EDS), and UV-spectroscopy analysis. It was found that the bandgap of PP+1%CdS/ZnS; PP+3%CdS/ZnS, and PP+5%CdS/ZnS; PP+10%CdS/ZnS nanocomposites is 5.2 eV, 5.1 eV, 4.6 eV, respectively. SEM analysis showed that the ZnS and CdS nanoparticles are evenly distributed in the polymer matrix. Furthermore, the average size of nanoparticles in the PP+3%CdS/ZnS, PP+5%CdS/ZnS nanocomposite is 40-54 nm, 29-56 nm, respectively. Photoluminescence properties of hybrid PP+CdS/ZnS nanocomposites were also investigated. It was established that introduction of ZnS and CdS semiconductor nanoparticles into the polypropylene matrix leads to expanding the region of the spectral sensitivity of hybrid nanocomposites. The photosensitivity of PP+CdS/ZnS nanocomposite films was also investigated.

Synergic effect of graphene nanoplatelets and carbon nanotubes on the electrical resistivity and percolation threshold of polymer hybrid nanocomposites

Synergic effect of graphene nanoplatelets and carbon nanotubes on the electrical resistivity and percolation threshold of polymer hybrid nanocomposites

Polymeric hybrid nanocomposites processing and finite element modeling: An overview.

Polymeric hybrid nanocomposites, due to improved mechanical, thermal, and electrical properties, are key factors in recent technologies. Because of anisotropic characteristics of polymeric hybrid nanocomposites, mechanical properties and their behavior are very difficult to predict. If they are fabricated with complicated woven fabric patterns, it becomes more difficult to predict. This review discusses in detail the properties and manufacturing methods of various fibers, focuses on different manufacturing, processing, and characterization techniques used for polymeric hybrid nanocomposites. Theoretical composite models and some recent advances in modeling and simulation techniques for polymer nanoparticle composites are discussed and thus this review can provide significant guidelines for the development of manufacturing, characterization, testing, modeling, and simulation techniques for high performance hybrid polymer nanocomposites as current state of art.

All in one: The preparation of polyester/silica hybrid nanocomposites via three different metal-free click reactions

The development of innovative routes for the preparation of hybrid polymer nanocomposites is an active area of research for engineering applications. In this study, we have utilized three different click chemistry reactions; aza-Michael, thiol-Michael, and metal-free azide-alkyne cycloaddition reactions, and prepared hybrid nanocomposites through the reactions between electron-deficient alkyne-containing polyester and modified silica nanoparticles bearing either azide, thiol, or amine groups. The modification of the silica nanoparticles was characterized by Fourier transform infrared spectroscopy and thermogravimetric analysis. The formation of the hybrid nanocomposites was verified by measuring their gel contents. The mechanical, thermal, and optical properties of the hybrid nanocomposites were also determined. The gel content of the prepared hybrid nanocomposites reached almost 88%. Modified silica nanoparticles showed a much uniform dispersion in the polymer matrix when compared to neat silica nanoparticles. A dramatic increase both in modulus and Tg values was observed for the hybrid nanocomposites.

PVA/MMT and (PVA/PVP)/MMT hybrid nanocomposites for broad-range radio frequency tunable nanodielectric applications

Electrical and electronic device applications of the hybrid nanocomposite materials are primarily identified from their frequency dependent dielectric properties. In this context, herein, we report the complex dielectric permittivity of poly(vinylalcohol)(PVA)/montmorillonite(MMT) and PVA/poly(vinylpyrrolidone)(PVP)/MMT nanocomposites with varying MMT nanoclay amounts up to 10 wt% and the frequency from 1 MHz to 1 GHz, in order to address their nanodielectric uses in biodegradable electronic devices operative at ultrahigh frequencies. These melt compounded prepared hybrid polymer nanocomposites (PNCs) showed an increase in dielectric permittivity by about 20% at 1 MHz when the MMT concentration was increased, and a gradual decrease with the rise in frequency which revealed their nanofiller concentration and frequency tunable nanodielectric behaviour. The PVA/MMT nanocomposites have high dielectric permittivity as compared to that of the (PVA/PVP)/MMT nanocomposites confirming that the dielectric properties of these PNCs can also be controlled by considering an appropriate composition polymer blend matrix.

Mechanical and Thermal Properties of Graphene based Hybrid Polymer Nanocomposites - A Review

Graphene-based materials are platelets of one or several layers that can be supplied by substance techniques in mass quantities. Therefore we present a report on polymer nanocomposites, including late work using graphite nanoplatelet fillers, using graphite-based fillers. In addition to techniques for the dispersion of these materials in various polymer grids, various courses used to manufacture graphemic materials are discussed. In addition, the mechanical and thermal characteristics of these composites are examined and The characteristics of graphene-based materials and their dispersion condition in the grid will be studied. A diagram of possible uses for these composites and existing challenges in the field is geared to the future and is aimed at enhancing the materials that are promising. In this review, the analysis of a few decent articles focused on half and half of the composites of graphene and The adaptive impact of graphene with the other nanoparticles in order to calculate its effects on the composite mechanical properties.

Nanostructured Polymer Composite Electrolytes with Self-Assembled Polyoxometalate Networks for Proton Conduction

Nanostructured Polymer Composite Electrolytes with Self-Assembled Polyoxometalate Networks for Proton Conduction

The mechanisms behind the tribological behaviour of polymer matrix composites reinforced with TiO2 nanoparticles

In this present work, the sliding wear behaviour of hybrid polymer nanocomposites was investigated under different loading conditions and against different counterface roughness. Two different polymers matrices, epoxy and polyamide 66, with classic micro-sized short carbon fiber and graphite flakes as tribo-fillers were investigated with and without TiO2 reinforcing nanoparticles. It was found that the synergistic effect between nanoparticles and micro-sized fillers on friction and wear performance depended on the tribological system involved. In particular, for epoxy-based composites, the incorporation of TiO2 nanoparticles was only beneficial against a sufficiently rough disc but detrimental otherwise. Whilst for polyamide nanocomposites, the combination of nanoparticles and other fillers resulted in low friction and wear against both rough and smooth disks, particularly at higher applied contact pressures. When the cross-sections of the transfer films were analysed using a high-resolution SEM, it was found that TiO2 nanoparticles are only beneficial if they can blend with other wear debris to form a TiO2-enriched transfer film. The strengthened film provides the support required for other dislodged TiO2 nanoparticles to achieve the rolling effect, thus reducing friction and wear. In contrast, if TiO2 cannot effectively blend into the transfer film, TiO2 nanoparticles act as an abrasive that readily abrades away the comparatively softer film, thus exposing the polymer to fresh asperities on the steel counterface, a detrimental outcome to both friction and wear. Hence, to design high wear resistant composite materials, it is important to understanding the interactions between different tribo-fillers for particular circumstances or contact conditions.

Signal Conditioning provided by Sensitive Elements of Electric Bioimpedance Sensors

Dry polarizable electric bioimpedance sensors for ECG (electrocardiogram) monitoring requires the use of signal conditioning electronic circuits that take over alternating ΔU voltages with a frequency of 40 kHz and peak-to-peak amplitude in the range of 10-50 mV. The sensitive elements of these sensors are made of sensitive materials like as conductive polymer polypyrrole or hybrid nanocomposite with 10 and 20% Ag incorporated in the polypyrrole polymer. The useful signal is picked up in differential mode by an instrumentation amplifier. The gain of the instrumentation amplifier is set to A = 100 by connecting a single external resistor, RG. The problem of eliminating the mass loops and obtaining a common mode signal is solved by using an amplifier with galvanic isolation, with the amplification factor A = 1, supplied with double differential voltage. To reject any parasitic signals that may accompany the useful signal, an electronic bandpass filtering module is used. Electrical measurements were performed which showed the accuracy of the signal amplified by the electronic instrumentation amplifier module used in the "differential mode" connection.

The synergistic effect on the thermomechanical and electrical properties of carbonaceous hybrid polymer nanocomposites

In this work, nanocomposites, based on linear low‐density polyethylene (mLLDPE), produced by metallocene catalyst, were prepared and experimentally investigated by means of thermomechanical-electrical properties and Raman spectroscopy. In particular, scanning electron microscopy (SEM), broadband dielectric spectroscopy (BDS), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), tensile and creep testing have been carried out. Several types of carbonaceous nanomaterials, including carbon nanotubes (CNTs), carbon nanofibers (CNFs) and graphene nano-fillers (GO), which have attracted significant attention for a variety of applications, were employed for the preparation of hybrid and non-hybrid nanocomposites at various loadings. It was found that the simultaneous incorporation of two different nanofiller types into a polymeric matrix, revealed better thermomechanical performance, while in particular the combination of CNTs and GO exhibited a synergistic effect between the nanofillers, supported also by BDS and Raman results. Therefore, the results of the present study offer a new perspective for the potential of mLLDPE/hybrid nanocomposites in targeted applications.

ICMMS-2: Application of Cs/ZnO/GO Hybrid Nanocomposite for Enhanced Inter-behavior of Electronic Properties and Thermal Stability as Corrosion Inhibitor

Polymer hybrid nanocomposites are considered to be one of the most promising materials which in turn acquires new, multiple and improved properties such as optical properties and electrical conductivity used for various applications in the fields of optical integrated circuits, sensors, adhesives, coatings and corrosion inhibitors for metal protection. At the present time graphene oxide hybridization with metal oxide modified carbohydrate polymers performance for corrosion inhibition for metal. Hybrid nanocomposite Cs/ZnO/GO was considered to be studied by DFT theory. The considered Cs/ZnO/GO model structure were studied in the two interaction states once as adsorb state and once as complex state. Hybrid nanocomposite electronic properties and thermal stability in all designated states have been evaluated. B3LYP/LANL2DZ was used to calculate TDM, HOMO/LUMO band gap energy and MESP for hybrid Cs/ZnO/GO nano composite assumptions. Additionally, QSAR descriptors for thermal stability study were also calculated for the same interactions. The most certainly stable structure of the hybrid nanocomposite Cs/ZnO/GO was found to occur through OH of the carboxyl group COOH of GO in complex mechanism and through O of the carboxyl group COOH of GO in adsorb mechanism. It is also found that the structure Cs/ZnO/GO occurs by O of the carboxyl group COOH of GO in adsorb mechanism has a significant improvement in electronic properties and thermal stability with band gap 0.1750 eV that it could be used as Corrosion Inhibitor.

Optical characterization of different oxide nanomaterials dispersed PVA/PEO blend matrix-based hybrid polymer nanocomposites for advances in optoelectronic device technologies

Optical properties of different oxide nanomaterials (viz. zinc oxide (ZnO), tin oxide (SnO2), silica (SiO2), and alumina (Al2O3)) as nanofillers (NFs) and a host polymer matrix of poly(vinyl alcohol) (PVA)/poly(ethylene oxide) (PEO) blend based hybrid polymer nanocomposites (HPNCs) have been investigated by employing ultraviolet-visible (UV-Vis) spectroscopy. The UV-Vis absorbance spectra over the photons wavelength range 200-800 nm, and the absorption coefficient, energy bandgap, and Urbach energy of the PVA/PEO/NFs HPNC films are determined and reported. The dependence of the optical characteristics of these HPNCs on the type of oxide nanofillers and their concentration have been studied which is found correlated with the optical properties of the nanofillers. Considering the results, suitability of PVA/PEO/NFs materials as potential candidates for UV-shielder, light diffuser, bandgap tuner, and photo-sensor/detector in the design and evolution of various flexible-type optoelectronic devices/components have been discussed.

The Effects of Unbleached and Bleached Nanocellulose on the Thermal and Flammability of Polypropylene-Reinforced Kenaf Core Hybrid Polymer Bionanocomposites.

The thermal, thermo-mechanical and flammability properties of kenaf core hybrid polymer nanocomposites reinforced with unbleached and bleached nanocrystalline cellulose (NCC) were studied. The studied chemical composition found that unbleached NCC (NCC-UB) had 90% more lignin content compared to bleached NCC (NCC-B). Nanocelluloses were incorporated within polypropylene (PP) as the matrix, together with kenaf core as a main reinforcement and maleic anhydride grafted polypropylene (MAPP) as a coupling agent via a melt mixing compounding process. The result showed that the thermal stability of the nanocomposites was generally affected by the presence of lignin in NCC-UB and sulfate group on the surface of NCC-B. The residual lignin in NCC-UB appeared to overcome the poor thermal stability of the composites that was caused by sulfation during the hydrolysis process. The lignin helped to promote the late degradation of the nanocomposites, with the melting temperature occurring at a relatively higher temperature of 219.1 °C for PP/NCC-UB, compared to 185.9 °C for PP/NCC-B. Between the two types of nanocomposites, PP/NCC-B had notably lower thermo-mechanical properties, which can be attributed to the poor bonding and dispersion properties of the NCC-B in the nanocomposites blend. The PP/NCC-UB showed better thermal properties due to the effect of residual lignin, which acted as a compatibilizer between NCC-UB and polymer matrix, thus improved the bonding properties. The residual lignin in PP/NCC-UB helped to promote char formation and slowed down the burning process, thus increasing the flame resistance of the nanocomposites. Overall, the residual lignin on the surface of NCC-UB appeared to aid better stability on the thermal and flammability properties of the nanocomposites.