Polymer Nanocomposite Materials Research Articles

Fabrication, surface characterization and optical behavior of flexible PVA/Nd2O3 polymer nanocomposites materials for optoelectronics applications

The nanocomposite PVA/Nd2O3 with novel properties, that composed of Neodymium (III) oxide (Nd2O3) and polyvinyl alcohol (PVA), was synthesized by the casting preparation method for applied as flexible films for optoelectronic. The techniques of the FTIR, XRD, SEM and EDX showed that the PVA/Nd2O3 were successfully synthesized. The successful inclusion of Nd2O3 into PVA is indicated by a reduction in PVA/Nd2O3 peak intensities as observed by the FTIR and XRD. Additionally, the UV/Vis technique was used to record the optical behavior at wavelengths between 200 and 1100 nm. The measurements of carbon clusters, band gap, absorption edge, and band tail were determined. The band gap decreases from 5.01 eV to 4.60 eV and the band tail changes from 1.8 eV to 2.85 eV when the Nd2O3 is raised from 5 % to 20 %. In addition, the absorption edge reduced from 5.06 eV for PVA to 4.92, 4.81, 4.72, and 4.49 eV, accordingly, when 5 %, 10 %, 15 %, and 20 % of Nd2O3 are introduced in the composite. The result showed the composites made with PVA and Nd2O3 have excellent optical characteristics, especially in the UV–visible spectrum, where they are highly reflective and absorbent. The study emphasizes the fabricated composites enhanced optical transparency and absorption properties, which make it a good materials for uses in photonic devices, sensors, and optical instruments.

Effect of Bismuth Ferrite Nanoparticles on Physicochemical Properties of Polyvinylidene Fluoride-Based Nanocomposites

Bismuth ferrite (BiFeO3, BFO) is one of the few single-phase crystalline compounds exhibiting strong multiferroic properties at room temperature, which makes it promising for use in various fields of science and technology. The remarkable characteristics of BFO at the nanoscale position it as a compelling candidate for enhancing the functionalities of polymeric nanocomposite materials. In this study, we explore the fabrication of polyvinylidene fluoride (PVDF) nanocomposites with a variable content of BFO nanopowders (0, 5, 10, 15, 20, and 25 wt%) by solution casting in the form of thin films with the thickness of ~60 µm. Our findings reveal that the presence of BFO nanoparticles slightly facilitates the formation of β- and γ-phases of PVDF, known for their enhanced piezoelectric properties, thereby potentially expanding the utility of PVDF-based materials in sensors, actuators, and energy harvesting devices. On the other hand, the increase in filler concentration leads to enlarged spherulite diameter and porosity of PVDF, as well as an increase in filler content above 20 wt% resulting in a decrease in the degree of crystallinity. The structural changes in the surface were found to increase the hydrophobicity of the nanocomposite surface. Magnetometry indicates that the magnetic properties of nanocomposite are influenced by the BFO nanoparticle content with the saturation magnetization at ~295 K ranging from ~0.08 emu/g to ~0.8 emu/g for samples with the lowest and higher BFO content, respectively.

Rational Design of Oil-Resistant and Electrically Conductive Fluorosilicone Rubber Foam Nanocomposites for Sensitive Detectability in Complex Solvent Environments.

Recent years have witnessed the explosive development of highly sensitive smart sensors based on conductive polymer foam materials. However, the design and development of multifunctional polymeric foam composites as smart sensors applied in complex solvent and oil environments remain a critical challenge. Herein, we design and synthesize vinyl-terminated polytrifluoropropylmethylsiloxane through anionic ring-opening polymerization to fabricate fluorosilicone rubber foam (FSiRF) materials with nanoscale wrinkled surfaces and reactive Si-H groups via a green and rapid chemical foaming strategy. Based on the strong adhesion between FSiRF materials and consecutive oxidized ketjen black (OKB) nano-network, multifunctional FSiRF nanocomposites were prepared by a dip-coating strategy followed by fluoroalkylsilane modification. The optimized F-OKB@FSiRF nanocomposites exhibit outstanding mechanical flexibility in wide-temperature range (100 cycle compressions from -20 to 200 °C), structure stability (no detached particles after being immersed into various aqueous solutions for up to 15 days), surface superhydrophobicity (water contact angle of 154° and sliding angle of ∼7°), and tunable electrical conductivity (from 10-5 to 10-2 S m-1). Additionally, benefiting from the combined actions of multiple lines of defense (low surface energy groups, physical barriers, and "shielding effect"), the F-OKB@FSiRF sensor presents excellent anti-swelling property and high sensitivity in monitoring both large-deformation and tiny vibrations generated by knocking the beaker, ultrasonic action, agitating, and sinking objects in weak-polar or nonpolar solvents. This work conceivably provides a chemical strategy for the fabrication of multifunctional polymeric foam nanocomposite materials as smart sensors for broad applications.

Mechanical properties of polymer composite films with ZnO nanoparticles synthesized in low-temperature plasma under ultrasonic cavitation

Abstract In this study, polymer nanocomposite materials consisting of the copolymer of ethylene and vinyl acetate as a matrix and nanoparticles of zinc oxide as a filler have been obtained and examined by physicochemical and mechanical methods. Zinc oxide nanoparticles used in this study were fabricated using the plasma discharge under the effect of intensive ultrasonic cavitation. To ensure that resulting nanocomposites will acquire homogeneous distribution of filler nanoparticles, solution technology was utilized followed by the melt compounding technique, and also nanoparticles treated and non-treated with ultrasound were applied. The fabricated samples of nanocomposite material films were examined by X-ray phase analysis, then X-ray fluorescence analysis as well as scanning electron microscopy. The differences between the samples were demonstrated: when the nanoparticles without ultrasonic treatment were used, the particles were found to be more strongly aggregated within the bulk of the composite material and the average size of particles was visually larger in comparison to the sample filled with nanoparticles subjected to ultrasonic action. Finally, studies of the tensile strength and relative deformation of the samples were carried out. From the results of mechanical tests, it can be seen that, according to both studied parameters, there is an optimal concentration of ZnO nanoparticles. For tensile strength, the highest result was obtained at a concentration of nanoparticles of 3%, and for the relative elongation to rupture of the sample, the highest value was achieved at a concentration of nanoparticles of 2%.

Utilizing a novel green ternary polymeric nanocomposite material to remove tetracycline antibiotic effectively from aqueous solutions

Utilizing a novel green ternary polymeric nanocomposite material to remove tetracycline antibiotic effectively from aqueous solutions

In Ukrainian

Due to the variety of their forms and properties, silver nanoparticles (AgNPs) are promising for obtaining nanomaterials with various functional applications. Today, regardless of the method of obtaining AgNPs, there is a problem of stabilizing their surface to prevent aggregation, which significantly reduces their activity and prevents uniform distribution during the preparation of nanomaterials. The aim of this work was the synthesis of silver nanoparticles using an oligomeric ionic liquid (OIL) and the study of their structure and antimicrobial properties. In this work, for the first time, an anionic OIL with a hyperbranched structure developed by us was used as a surface stabilizer in the synthesis of AgNPs. The synthesis of AgNPs was carried out by the reduction of Ag ions in the composition of AgNO3 with trisodium citrate in the presence of this OIL. Using the methods ofUV-vis and FTIR spectroscopy, X-ray analysis, electron microscopy and the disc-diffusion method, the peculiarities of the structural organization of AgNPs and their antimicrobial properties were studied. UV-visible spectroscopy data indicate the formation of silver nanoparticles and their spherical or quasi-spherical shape. It was found that there are adsorbed ionic and carbonyl groups on the surface of the formed AgNPs, and the formation of host-guest complexes between OIL and silver ions was revealed using FTIR. The formation of AgNPs and complexes between OIL and silver ions is also confirmed by X-ray diffraction. According to electron microscopy, the size of the synthesized nanoparticles varies from 5 to 16 nm, with an average value of 10.2 nm. This average value is very close to the value of 9.3 nm obtained from the results of X-ray analysis. The synthesized silver nanoparticles showed a very high antimicrobial activity against C. albicans fungi, while the width of the inhibition zone (d) was 34 mm. Also, the AgNPs powder shows very high activity against gram-positive bacteria S. aureus (d = 30 mm) and gram-negative bacteria E. coli (d = 12 mm). The approach developed by us to the synthesis of AgNPs in the presence of OIL as a surface stabilizer with certain functionalization of the latter opens up new opportunities in the synthesis of AgNPs and the preparation of highly dispersed related systems, including functionalized nanocomposite polymer materials with antimicrobial properties.

Using Magnetic Molecularly Imprinted Polymer Technology for Determination of Fish Serum Glucose Levels.

In this study, a highly efficient magnetic molecularly imprinted polymer nanocomposite material was prepared using multi-walled carbon nanotubes as carriers. The characterization of the obtained nanocomposite material was conducted using Fourier transform infrared spectroscopy, a vibrating sample magnetometer, a thermogravimetric analyzer, a scanning electron microscope, and a transmission electron microscope. The adsorption properties of the nanocomposite material were evaluated through adsorption experiments, including static adsorption, dynamic adsorption, and selective recognition studies. The prepared nanocomposite material, serving as a selective adsorbent, was applied in magnetic solid-phase extraction. Subsequently, the derivatized samples were analyzed for glucose in fish serum using liquid chromatography-tandem mass spectrometry. Under optimal conditions, the detection limit was 0.30 ng/mL, the quantitation limit was 0.99 ng/mL, satisfactory spiked recovery rates were obtained, and the relative standard deviation was less than 1.1%. Using 2-deoxy-D-ribose as the template molecule and a structural analog of glucose allowed us to eliminate the potential template leakage in qualitative and quantitative analyses, effectively avoiding the issues of false positives and potential quantitative errors, compared to traditional methods. A method for detecting glucose levels in fish serum based on molecularly imprinted polymer technology has been successfully developed to determine the stress and health levels of fish.

Review on the Encapsulation, Microencapsulation, and Nano- Encapsulation: Synthesis and Applications in the Process Industry for Corrosion Inhibition

Background: Surfaces of materials often corrode and deteriorate due to environmental conditions. There are various widely used methods of reducing corrosion rates to increase the lifetime of materials and equipment. Recently, there has been a growth in the use of nanotechnology to protect metals against corrosion. The application of nano-encapsulation techniques in the process industry is one of the important eras of nanotechnology. This review paper focuses on encapsulation, microencapsulation, and nano-encapsulation methods, emphasizing nanoencapsulation applications as corrosion inhibitions in the process industry. Methods: Materials based on the self-healing mechanism were used in advanced applications such as structures, batteries, and coatings. These technologies may be studied in two ways: compounds with intrinsic self-healing properties and extrinsic self-healing materials with additives such as microcapsules filled with healing agents. Nano-coatings have advantages, like accelerated ground hardness, adhesive energy, long-time period and/or high-temperature corrosion resistance, tribological residence enhancement, etc. Nano-coatings can also be carried out in thinner and smoother layers, considering flexibility, accelerated performance, decreased fuel costs, and smaller carbon footprints, as well as occasional maintenance. The review of corrosion characteristics of polymeric nanocomposite material was discussed in this paper. Results: This review paper presents an updated overview summarizing the latest advances in the various micro/nanocarriers used for self-healing corrosion protective coatings. Conclusion: With this information, the investigators will be able to modify the structure of the inhibitor to get the necessary corrosion inhibition capabilities. The need for a physical examination is rising as a result.

Experimental and molecular dynamics simulation based investigation to understand tribological performance of graphene reinforced thermoplastic polyurethane (Gr/TPU) nanocomposites

Ongoing innovative research in tribology aims to develop high-performance polymer nanocomposite (PNC) materials that offer significant improvements in efficiency, reliability, and durability across various engineering systems. Selection of appropriate nanoreinforcements is crucial for maximizing the tribological behavior in PNCs. The primary objective is to investigate how various factors, such as graphene (Gr) loadings, processing techniques, normal loading, and sliding velocity influence the tribological behavior of thermoplastic polyurethane (TPU) and graphene reinforced thermoplastic polyurethane (Gr/TPU) nanocomposites using molecular dynamics (MD) simulation and experiments. Nanocomposite materials fabricated by ultrasonication methods, test specimens are prepared in appropriate dimensions as per ASTM (American Society for Testing and Materials) and DIN (Deutsches Institut für Normung) standard. MD simulations are conducted on the developed plate and rod models under different sliding velocity, pressing and stabbing depth conditions to understand fundamental insights into the friction and wear mechanisms of Gr/TPU nanocomposites at the atomic level. Morphological studies using scanning electron microscopy (SEM) micrographs indicate no case of Gr agglomeration up to 3 wt% Gr/TPU nanocomposite. Energy dispersive spectroscopy (EDS) analysis confirms presence of Carbon (c), Nitrogen (N) and Oxygen (O) in Gr/TPU nanocomposites. Finally the obtained results from MD simulation and experiments show a significant trend of similarity.

Silicone Nanocomposites with Enhanced Thermal Resistance: A Short Review.

Continuous technological progress places significant demands on the materials used in increasingly modern devices. An important parameter is often the long-term thermal resistance of the material. The use of heat-resistant polymer materials worked well in technologically advanced products. An economically justified direction in searching for new materials is the area of polymer nanocomposite materials. It is necessary to appropriately select both the polymer matrix and the nanofillers best able to demonstrate the synergistic effect. A promising area of exploration for such nanocomposites is the use of organosilicon polymers, which results from the unique properties of these polymers related to their structure. This review presents the results of the analysis of the most important literature reports regarding organosilicon polymer nanocomposites with increased thermal resistance. Particular attention was paid to modification methods of silicone nanocomposites, focusing on increasing their thermal resistance related to the modification of siloxane molecular structure and by making nanocomposites using inorganic additives and carbon nanomaterials. Attention was also paid to such important issues as the influence of the dispersion of additives in the polymer matrix on the thermal resistance of silicone nanocomposites and the possibility of modifying the polymer matrix and permanently introducing nanofillers thanks to the presence of various reactive groups. The thermal stability mechanism of these nanocomposites was also analysed.

ZnO nanofiller concentrations modified P(VDF-HFP)/PEO polymer matrix-based nanocomposites of enhanced optical and dielectric properties for emerging optoelectronic and energy storage devices

Wide bandgap metal oxide nanoparticles incorporated polymer blend matrix-based polymer nanocomposites (PNCs) are established as innovative multifunctional and properties tunable materials in the dimensional design and fabrication of promising performance extensive flexible type advanced devices. For further progress in these materials, herein, the detailed structural and promising properties of solution-cast prepared ternary PNC films, composed of poly(vinylidene fluoride-co-hexafluoropropylene) P(VDF-HFP)/ poly(ethylene oxide) PEO (50/50 wt%) host matrix and zinc oxide (ZnO) nanofiller (0, 1, 2, 5, and 10 wt%), are characterized. A sequence of employed experimental techniques, namely SEM, XRD, FTIR, and DSC, confirm that the surface morphology, polymorphic crystallographic character, polymer-polymer interactions, polymer-nanoparticle interfaces, crystalline phase thermal transitions, and degree of crystallinity of these PNCs largely affected with varying nanofiller concentrations. The optical study conducted with a UV–Vis spectrophotometer revealed high photo sensing and UV shielding characteristics with an energy bandgap of about 3.0 eV, demonstrating widespread applications of these semiconducting PNC materials in emerging optoelectronic device technologies. The broadband dielectric spectroscopic (BDS) characterization over the 20 Hz–1 GHz range explained harmonic field frequency and nanofiller concentration tunable dielectric permittivity (about 3 to 13) with low losses and multiple relaxation processes, predominantly ruled by microstructural interfaces and interactions developed in these ternary hybrid complex materials. The meaningful broadband dielectric characteristics of P(VDF-HFP)/PEO/ZnO materials demonstrated that they could be used as innovative nanodielectrics for energy storage purposes in capacitive devices, and flexible dielectric substrate and insulators for the fabrication of frequency-adjustable discrete and integrated microelectronic devices.

Synergistic effect of polymer blend compositions on the structural, thermal, optical, and broadband dielectric properties of P(VDF-HFP)/PEO/ZnO polymer nanocomposites

Polymer nanocomposites (PNCs) composed of poly(vinylidene fluoride-co-hexafluoropropylene) (P(VDF-HFP))/ poly(ethylene oxide) (PEO) blend host matrix of varying compositions i.e., xP(VDF-HFP)/(100–x)PEO with x values 20, 50, and 80 wt%, and zinc oxide (ZnO) as nanofiller (2 wt%) are prepared by state-of-the-art homogenized solution cast method. The SEM micro-images of these PNC films revealed that the polymer blend compositions considerably affect the polymers miscibility, spherulitic morphologies, and crystalline phases. FTIR spectra demonstrated that the P(VDF-HFP) and PEO chain interactions in these PNCs change significantly with the polymer blend compositions. The DSC results revealed a decrease in PEO crystallite temperature and degree of crystallinity with the increase of P(VDF-HFP) amount in the blend matrix of these PNC materials. Analysis of UV-Vis spectra categorized these PNCs of wide band gap (∼ 3.1 eV) semiconductive optical materials. Broadband frequency range (20 Hz–1 GHz) dielectric dispersion demonstrated that 50P(VDF-HFP)/50PEO-2 wt% ZnO composition based nanodielectric film has a relatively high dielectric constant, whereas the chain segmental and dipolar reorientation relaxation processes are strongly polymer blend composition dependent for these PNC materials. The experimental results are discussed in detail concerning the multifunctionality of these PNCs as promising candidates for innovation in flexible optoelectronic and nanodielectric-based microelectronic devices.

Fe-nanoparticle effect on polypropylene for effective radiation protection: Simulation and theoretical study

An evaluation of the gamma-neutron shielding capabilities of polymer nanocomposite materials based on polypropylene and iron nanoparticles is presented in this study. The chemical composition of the materials is (100-x) PP-Fex, (where x = 0.1, 0.3, 0.5, 1, 2 and 5 wt percent). For the proposed polymer samples with photon energies ranging from 30 to 2000 KeV, the mass attenuation coefficient (MAC), a crucial parameter for studying gamma-ray shielding capability, was calculated using the Geant4 Monte Carlo code. Results were compared with those predicted by EpiXS. The values of the Geant4 code and the EpiXS software were both found to be in excellent agreement. Using the mass attenuation coefficient values, we determined the linear attenuation coefficients, electron density, effective atomic number, and half value layer for all the samples. The shielding properties of the polymer samples were also evaluated by estimating both the fast neutron removal cross-section and the mean free path of the fast neutron at energies between 0.25 and 5.5 keV. The study's findings indicate a positive correlation between the Fe nanoparticle content and the gamma-ray shielding performance of PP-Fe polymer samples. Out of the several glasses that were evaluated, it was found that the PP-Fe5 polymer sample demonstrates the highest efficacy in terms of gamma-ray shielding. Moreover, the polymer sample PP-Fe5, which consists of 5 mol% of iron (Fe), exhibits the highest value of ∑R (1.10650 cm-1) and the lowest value of the mean free path for fast neutrons. This indicates that the PP-Fe5 possesses better gamma-neutron shielding efficiency.

In vivo validation of a mechanically adaptive microfluidic intracortical device as a platform for sustained local drug delivery

Introduction: Intracortical microelectrodes (IME) are vital to properly functioning brain-computer interfacing (BCI). However, the recording electrodes have shown a steady decline in performance after implantation, mainly due to chronic inflammation. Compliant materials have been explored to decrease differential strain resulting in lower neural inflammation. We have previously developed a fabrication method for creating mechanically adaptive microfluidic probes made of a cellulose nanocrystal (CNC) polymer nanocomposite material that can become compliant after implantation. Here, we hypothesized that our device, would have a similar tissue response to the industry standard, allowing drug delivery therapeutics to improve neural inflammation in the future.Methods: RNA expression analysis was performed to determine the extent of neural inflammation and oxidative stress in response to the device compared to controls and to naïve shame tissue.Results: Results presented for both four- and eight-weeks post-implantations suggest that our device offers a promising platform technology that can be used to deliver therapeutic strategies to improve IME performance.

Electrospray deposited plant-based polymer nanocomposite coatings with enhanced antibacterial activity for Ti-6Al-4V implants

The present study was designed to apply the Electrospray Deposition (ESD) coating on metallic biomaterials used in dentistry with plant-based polymer nanocomposite materials. Nano silvers (AgNPs) were produced with an average size of 34 nm and homogenous distribution. As the nanosilver modification rate in the coatings increased, the surface roughness decreased compared with that of the neat sample. The most mechanically and chemically stable coating samples were the 0.1 %, 0.3 %, and 0.5 % nanosilver-modified samples. In addition, plant extracts increased the mechanical strength of Polyvinyl Alcohol (PVA) coatings by at least two times compared to that of neat coatings. Atomic Force Microscopy (AFM) images revealed that the surface roughness of the nanosilver-modified coatings was lower than that of the plant extract-modified and neat samples. It was observed that bacterial growth could be reduced by up to 100 times with increasing nano‑silver ratio in all nano-silver-modified coatings. Toxicity tests confirmed that the green synthesized nano-silvers did not show toxic effects on HaCaT live cells and A549 lung cancer cells, with the use of concentrations of 62 μg/mL and below in coatings.

Comparative analysis of the structural, optical, mechanical, and electrical properties of PMMA/PU blend‐based nanocomposites with FeVO4 nanofiller for energy storage devices

AbstractThe best materials for enhanced energy storage capacitors in electrical systems are polymer nanocomposites films. Therefore, using the solution casting approach, we created a unique series of FeVO4 nanofiller‐embedded polyurethane (PU) and polymethyl methacrylate (PMMA)‐based composites. Various techniques were used to describe the prepared films. XRD spectra were used to assess the crystallinity and crystallite size of nanocomposites. The XRD spectra were used to assess the crystallinity and crystallite size of nanocomposites. With rising nanoparticles (NPs) content up to samples with 1.5 weight percent of FeVO4, XRD demonstrated an increase in the amorphous phase of the polymer mixture, which was further supported by UV–Vis measurements. FTIR was used for determining the complexation of the FeVO4 with the polymer mixture. Calculations were used to determine optical properties such as the Urbach energy and energy bandgap. With a rise in FeVO4 NP concentration, the energy bandgap decreases while the Urbach energy increases. All samples' AC conductivity spectra exhibit Jonscher's power law (JPL) behavior. Studies on dielectric permittivity and electric modulus have also been conducted in order to comprehend the charge storage characteristics and conductivity relaxation. Whereas the frequency‐dependent increase in AC electrical conductivity, the ε′ and ε″ of PU/PMMA–FeVO4 nanocomposites drop with the rising of the electric field frequency. The high level of FeVO4 was shown to improve the AC conductivity, ε′ and ε″ values of the nanocomposites. Tensile strength was improved by 38% with the addition of FeVO4 NPs into the PU/PMMA blend. Experimental outcomes show that these polymer nanocomposites materials are multifunctional and can be used as low‐permittivity nanodielectric insulators and substrates to design the next generation of flexible electronic devices and also there can be used to create a variety of advanced optoelectronic and organic electronic devices.

A short review on machine learning for the purpose of optimizing and predicting the properties of polymeric nanocomposites

The mechanical, electrical, and thermal properties of nanocomposite materials are vastly superior to those of their bulk counterparts. Adding nanoparticles (sometimes called nanofillers or nano reinforcing) to a material is a common way to make the polymeric matrix more robust. The automobile, aviation, aerospace, maritime, and municipal industries can all benefit greatly from these materials. Common types of carbon-based nanomaterials include graphene sheets and carbon nanotubes. Their mechanical, electrical, and optical qualities are unparalleled.This material has the potential to be used in the development of synthetic scaffolding. According to their properties, nanofillers can be broken down into one of three broad categories. In this paper, we provide an overview of recent advances in the application of machine learning (ML)-driven approaches for the logical design of polymer nanocomposite materials. It has been found that nanocomposites in this setting can take on one of three distinct morphologies: phase separated, intercalated, or exfoliated. This is because the resulting mechanical and thermal properties are intimately tied to the particular morphologies that are developed. Melt mixing, compression moulding, and in-situ polymerization are common techniques for creating polymeric nanocomposites. When it comes to the toughness and rigidity of composites, stress transfer from the continuous phase to the dispersed phase is a crucial occurrence. Polymer nanocomposites are a class of nanomaterials that have the potential to be used in a variety of applications such as tissue engineering.

Fabrication, Structural Properties, and Electrical Characterization of Polymer Nanocomposite Materials for Dielectric Applications.

This research paper aims to fabricate flexible PVA/Cs/TiO2 nanocomposite films consisting of polyvinyl alcohol (PVA), chitosan (Cs), and titanium oxide (TiO2) for application in energy storage devices. The samples were analyzed using X-ray diffraction (XRD), atomic force microscope (AFM), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and energy dispersive X-ray (EDX) techniques. The impact of TiO2 on the electrical impedance, conductivity, permittivity, and energy efficiency of the PVA/Cs was determined in a frequency range of 100 Hz to 5 GHz. The XRD, FTIR, and EDX results showed the successful fabrications of the PVA/Cs/TiO2. The SEM and AFM images illustrated that the TiO2 was loaded and distributed homogenously in PVA/Cs chains. In addition, the electrical conductivity was enhanced from 0.04 × 10-7 S.cm-1 of PVA/Cs to 0.25 × 10-7 S.cm-1 and 5.75 × 10-7 S.cm-1, respectively, for the composite PVA/Cs/0.01TiO2 and PVA/Cs/0.1TiO2, and the dielectric constant grew from 2.46 for PVA/Cs to 7.38 and 11.93, respectively. These results revealed that modifications were made to the produced films, paving the way for using the composite PVA/Cs/TiO2 films in different energy applications, such as electronic circuits and supercapacitors.

Molecular Origin of the Reinforcement Effect and Its Strain-Rate Dependence in Polymer Nanocomposite Glass.

We investigate the molecular origin of mechanical reinforcement in a polymer nanocomposite (PNC) under a glass state via molecular dynamics simulations. The strength of the PNC system is found to be reinforced mainly via reduced plastic deformations of the nanoparticle neighborhood (NN). Such a reinforcement effect is found to decay with an increase in the strain rate. The Arrhenius-Eyring relation is used to analyze its origin. The amplitude of the reinforcement is found to be determined by the difference between the energy barrier (ΔE) for the activation of NN and the work (W) done by the applied stress to conquer that barrier. A larger strain rate is found to result in a larger W and, hence, a weaker reinforcement effect. Such a strain-rate dependence is verified in the experimental tensile tests of a poly(vinyl alcohol)/SiO2 composite system. These results not only provide a new understanding of the molecular origin of the reinforcement effect in the PNC system, but also pave the way for a better design of the PNC material properties.

Effective Changes In Polymer Nanocomposite Materials When They Are Modified with γ-Rays

Effective Changes In Polymer Nanocomposite Materials When They Are Modified with γ-Rays