Nanoparticles In Polymer Matrix Research Articles

Enhancing the cell viability and antibacterial properties of alginate-based composite layer by adding active particulates

Because of their exceptional biological, mechanical, and structural capabilities, polymer matrix composite materials are immensely appealing in the biomedical industry, particularly for surface activation of metallic implants and tissue engineering. The purpose of this research is to investigate the effect of adding 5% active metallic particles (Mg particles and Ag nanoparticles) to an alginate matrix on cell survival (fibroblast MG-36 cells), antibacterial activity, surface texture, roughness, and wettability. The incorporation of 5% Mg particles and Ag nanoparticles in polymeric matrix employed composite material with outstanding properties. The adding of Mg and Ag particles boosted wettability by decreasing the contact angle from 56.83° to 0°. The activity of Candida albicans and Porphyromanoas gingivalis was significantly reduced, particularly with Ag nanoparticles, which fight bacteria by blocking cell development and improving the antimicrobial properties of composite materials. The use of Ag nanoparticles to strengthen alginate resulted in higher fibroblast proliferation for MG-63 cell at the outer layer, which resulted in superior cell viability (24, 48, and 72). Meanwhile, due to Mg's high activity, the reverse effect was found when Mg particles were used, making the composite surface more active (enriched with Mg ions).

ФОРМУВАННЯ ТА ВЛАСТИВОСТІ СТРУКТУРОВАНИХ ПОЛІАКРИЛАМІДНИХ ГІДРОГЕЛІВ З НАНОЧАСТИНКАМИ CdS

The new method of obtaining nanocomposite hydrogels with embedded mineral nanoparticles has been proposed. CdS nanoparticles have been synthesized in situ in hydrogel matrix based on the copolymer of acrylamide and acrylic acid under the conditions of diffusion fluxes of Cd2+ та S2- structure-forming ions. The formation of CdS nanoparticles in polymeric matrix has been approved by the methods of XRD, energy- dispersive analysis, UV-spectroscopy. The influence of the content of polymer matrix onto physico- mechanical properties of hydrogel has been studied.

Comparing the flexural and morphological properties of dissimilar FFF-fabricated polymer composites

Additive manufacturing is becoming more and more significant for the production of engineering products. The global community of designers and manufacturers will undoubtedly benefit from identifying the process factors that could lead to superior mechanical behaviour. The incorporation of fibres and nanoparticles in polymer matrix is one of the most significant advancements in polymer fabrication. This study intends to investigate how the flexural behaviour of dissimilar polymer composites viz carbon fibre reinforced poly lactic acid (CF-PLA), carbon fibre reinforced poly ethylene terephthalate glycol (CF-PETG) and multi walled carbon nano tubes reinforced PLA (MWCNTs-PLA) are affected by process parameters viz nozzle diameter (0.2 mm, 0.4 mm, 0.6 mm), and infill pattern (triangular, honeycomb, rectilinear) through fused filament fabrication (FFF). Flexural testing was carried out on the fabricated specimens, and post to the testing, fractography has been carried out and statistical analysis of the observations is performed utilizing analysis of variance and Taguchi method. According to the observations, flexural strength of the polymer composite specimen increases with increase in nozzle diameter (ND). The flexural behaviour is also directly impacted with the variation of infill pattern (IP). Process parameter variations affect target factors differently depending on the fabricating material. For flexural behaviour, IP contributes 68.27% to CF-PLA, while ND contributes 88.96% to CF-PETG and 77.59% to MWCNTs-PLA. Overall, the highest flexural strength, 70.372 MPa, is exhibited by the specimen with ND 0.6 mm and rectilinear IP for MWCNTs-PLA as fabricating filament material. This study will aid researchers and designers in developing FFF-fabricated electrochemical energy storage devices with improved flexural behaviour of functional parts for a wide range of applications.

Direct Synthesis of Gold Nanoparticles in Polymer Matrix.

We report an original method for directly fabricating gold nanoparticles (Au NPs) in a polymer matrix using a thermal treatment technique and theoretically and experimentally investigate their plasmonic properties. The polymeric-metallic nanocomposite samples were first prepared by simply mixing SU-8 resist and Au salt with different concentrations. The Au NPs growth was triggered inside the polymer through a thermal process on a hot plate and in air environment. The Au NPs creation was confirmed by the color of the nanocomposite thin films and by absorption spectra measurements. The Au NPs sizes and distributions were confirmed by transmission electron microscope measurements. It was found that the concentrations of Au salt and the annealing temperatures and durations are all crucial for tuning the Au NPs sizes and distributions, and, thus, their optical properties. We also propose a simulation model for calculations of Au NPs plasmonic properties inside a polymer medium. We realized that Au NPs having large sizes (50 to 100 nm) play an important role in absorption spectra measurements, as compared to the contribution of small NPs (<20 nm), even if the relative amount of big Au NPs is small. This simple, low-cost, and highly reproducible technique allows us to obtain plasmonic NPs within polymer thin films on a large scale, which can be potentially applied to many fields.

Dramatically enhanced energy harvesting capability in sandwich-structure modulated piezoelectric nanocomposites

Piezoelectric energy harvesting devices (PEHs) offer great potential for diverse electronic applications. However, it is still a great challenge to well combine appropriate mechanical strength and high output performance in composite-type PEHs. Herein, the sandwich-structured composite-type PEHs for high-output mechanical energy harvesting using piezoelectric Barium titanate nanoparticles and poly(vinylidenefluoride-co-trifluoroethylene) (P(VDF-TrFE)) copolymers matrix is reported. By intentionally modulating the distribution of piezoelectric nanoparticles in polymer matrix, a highest output of ∼60 V (open-circuit voltage), and ∼65 μW/cm3 (power density at load resistance of 50 MΩ), respectively, was obtained. Via mechanical property and energy harvesting capability quantification, the dramatically improved energy harvesting capability is determined to be stemmed from the stress-enforcement in embedded piezoelectric nanoparticles and optimized piezoelectric response. Besides, the device presents a sufficient mechanical durability, which endows it the ability for long time stable operation. This work sheds light on a universal strategy for fabricating high-performance composite-type PEHs by constructing a gradient distribution of piezoelectric active nanoparticles in polymer matrix.

In-situ etching MOF nanoparticles for constructing enhanced interface in hybrid membranes for gas separation

Metal-organic frameworks (MOFs) based hybrid membranes have great potential for energy-efficient gas separation. However, the defective interface structure greatly depresses their separation performance. In this work, a distinctive interfacial design strategy via in-situ etching ZIF-8 nanoparticles is proposed to construct hybrid membranes with nearly defect-free interfaces. The nanoscale etching of ZIF-8 nanoparticles in polymer matrix with acid group (PI-COOHx) is well controlled by the amount of carboxyl group and reaction time. Owing to the strong coordination interaction between Zn2+ ions and –COOH groups, the residual ZIF-8 nanoparticles are tightly wrapped by polymer matrix. Molecular simulation was performed to study the in-situ etching ZIF-8 in PI-COOHx matrix in molecular level. The resulted hybrid membranes (PI-COOHx/E-ZIF-8) exhibit simultaneously enhanced permeability and selectivity with increasing filler loading content. Benefiting from the rational interfacial design, the effective loading content of ZIF-8 nanoparticles is up to 50 wt% for PI-COOH20/E-ZIF-8 membrane. The H2, CO2, and O2 permeability of the membrane are 3058.6, 1429.0, and 459.0 Barrer, increasing by 468.5%, 288.3% and 348.2%, respectively, of pristine PI-COOH20 membrane, and the gas selectivity for H2/N2, H2/CH4, O2/N2, and CO2/CH4 gas pairs are greatly improved from 20.3, 23.4, 3.9 and 16.0 of pristine PI-COOH20 membrane to 30.7, 37.6, 4.6 and 17.6. The comprehensive separation performance for H2/N2, H2/CH4, and O2/N2 gas pairs surpass the 2008 upper bound and approach the 2015 upper bound. Meanwhile, the CO2 plasticization resistance of PI-COOH20/E-ZIF-8 membrane also achieves significant improvement from 6 bar of PI-COOH20 membrane to 27 bar. This work provides an effective and robust strategy to effectively enhance the interfacial compatibility of hybrid membranes.

Nanoparticle layer via UV-induced directional migration of iron-doped titania nanoparticles in polyvinyl butyral films and superior UV-stability

The migration of nanoparticles in polymer matrix is significant for the structure and performance of polymer nanocomposites after the initial formation. However, the understanding and controlling of migration of nanoparticles in polymer matrix remains a challenge. Herein, we report using ultraviolet (UV) light to perform the directional migration of inorganic nanoparticles in polymer film, generating an ultrathin (100–200 nm) nanoparticle layer on the light exposure surface of the film. The prepared iron-doped titania nanoparticles (Fe–TiO 2 ) are initially uniformly dispersed into polyvinyl butyral (PVB) film, and homogeneous distribution remains unchanged even after thermal treatment. However, the UV irradiation induces the directional migration of nanoparticles towards the illuminated surface. The mechanism indicates that the directional migration of nanoparticles is related with the increase of interfacial energy and conformational entropic effect between Fe–TiO 2 and PVB upon UV irradiation. The formed nanoparticle layer endowed the PVB/Fe–TiO 2 film with superior UV-stability. Our work extends the study of controlling migration of nanoparticles in polymer matrix by applying external stimuli, and provides a novel strategy for the functionalization of polymer nanocomposite materials. • Iron-doped TiO 2 nanoparticles with low photocatalytic activity is prepared. • UV-induced unidirectional migration of iron-doped TiO 2 nanoparticles in polyvinyl butyral is firstly reported. • The mechanism of UV-induced migration of nanoparticles is investigated in detail. • A nanoparticle layer formed on the exposed surface by UV-induced unidirectional migration of nanoparticles. • Nanoparticle layer imparted superior UV-stability to polymer nanocomposite film.

Optical Active Thermal Stable Nanocomposites Using Polybutadiene-Based Polyurethane and Graphene Quantum Dot-MnO2

Synthesis and characterization of new polybutadiene-based polyurethane, graphene quantum dot-MnO2 nanoparticles, and relative nanocomposites were set as the aim of current artwork. For this purpose, a one-pot polymerization approach was employed in preparation of polyurethane through the reaction of amine polyol and toluene diisocyanate (TDI) in presence of DBTDL catalyst. Nanocomposites were synthesized using 1 to 3 incorporation percent of graphene quantum dot-MnO2 nanoparticles in polymer matrix. 1H-NMR and FT-IR spectroscopies confirmed successful synthesis of reaction products including graphene quantum dot-MnO2, polyurethane, and nanocomposites. UV-vis and PL spectrophotometry techniques were applied for achieving optical information of samples. Optical properties of nanocomposites were reserved properly with no great quenching. Thermal stabilities, degradation rates, and thermal characteristics of polyurethane and nanocomposites were investigated using TGA/DTG and DSC analysis. Thermal stability showed direct relationship to nanoparticle content, and 3%wt nanocomposite showed improved thermal behaviour in comparison with pure PU. SEM, XRD, and AFM techniques proved successful nanocomposite synthesis with detecting nanoparticle species and fine nanoparticle dispersion with improved topographic and morphologic characteristics making GQD-MnO2 polyurethane nanocomposites a good candidate for using in optical active and thermal stable coatings.

Effects of Hydrophilic Silica Nanoparticles on Morphology and Mechanical Properties of a Typical Tyre Compound

This research aimed to study the effects of adding hydrophilic silica nanoparticles as nanofiller on tread properties of a typical tyre compound. In this respect, four compounds were prepared as a representative of the tread of the tyre. The amount of 0, 1, 3, and 5 phr (parts of filler per hundred parts of rubber) of nanofiller were added by melt mixing method. Physical and mechanical properties of compounds were measured. The structure and morphology of the fractured surface of the compounds were characterized using field emission scanning electron microscopy (Fe-SEM). The results of cure and mechanical analysis of the compound series showed that the sample containing 3 phr of nanofiller possesses better properties. This observation is due to higher interaction between nanofiller and polymer macromolecules that causes better dispersion of the nanoparticles in polymer matrix.

Simultaneous improvements in antibacterial and flame retardant properties of PET by use of bio-nanotechnology for fabrication of high performance PET bionanocomposites

Recently, attentions to the applications of biotechnology and nanotechnology in the polymer industries have been greater than before. Hybrid nanocomposites containing multi-type of nano structures are widely established, but application of biotechnology for in-situ embedment of nanoparticles in polymer matrix is rarely reported. In this study, poly (ethylene terephthalate) (PET) based ternary bionanocomposites containing modified chitosan (phosphorylated chitosan) and nanosilver particles were prepared by simple eco-friendly method. Chitosan was selected as a biopolymer with respect to the biological activity and compatibility with PET. Phosphorylation of chitosan was achieved in order to introduce the phosphorus moieties as a flame retardant agent in PET matrix by using chemical approach. Also a cost-effective and environmentally friendly method was used for the in-situ fabrication and decoration of silver nanoparticles on to phosphorylated chitosan in PET matrix. Effects of the hybrid system (phosphorylated chitosan and silver nanoparticles) on the morphology, thermal behavior and antibacterial properties of the PET samples were investigated by different methods. The microstructure and homogeneity of the samples were analyzed by studying of dispersion of nanoparticles in PET via scanning electron microscopy. The antibacterial properties of PET nanocomposites can be improved by insertion of silver nanoparticles into the bulk of polymer matrix. Obtained results indicated that the PET/phosphorylated chitosan/silver nanocomposites showed a significantly higher growth inhibition rate compared with the PET and PET/phosphorylated chitosan blend. Also the flame retardant properties of PET nanocomposites were drastically enhanced.

Diffusion-assisted ultrashort laser pulse induced photothermal growth of core-shell nanoparticles in polymer matrix.

Light-to-heat conversion that occurs when irradiating a metal nanoparticle within a polymer matrix with ultrashort laser pulses initiates photothermal destruction of dissolved precursor molecules just near the nanoparticle. Extracted elementary species deposit on the nanoparticle surface, forming a core-shell structure. We construct an approximate analytical model for this process. The necessary step here is the diffusion of the precursor molecules towards the nanoparticle surface, replacing the broken ones. This diffusion can be a limiting factor for the rate of the shell growth. However, we show that because of the sharp localization of the process the precursor diffusion can successfully supply the growing shell with elementary species at realistic values of the precursor diffusion coefficient if the sample is kept in viscoelastic state at a temperature near the glass transition between the laser pulses. The main restriction on the obtained shell thickness comes from the requirement of matrix stability during the laser processing. Taking this restriction into account, the model allows estimating reachable shell thicknesses depending on the kinetic parameters of the precursor destruction reaction. This paper relies on numerous publications on photo/laser-induced growth of homogeneous metal or semiconductor nanoparticles within polymer matrices; however, this type of growth for compound core-shell nanoparticles is studied for the first time, to our knowledge.

Photochemical synthesis of bimetallic gold/silver nanoparticles in polymer matrix with tunable absorption properties: Superior photocatalytic activity for degradation of methylene blue

Bimetallic nanoparticles are widely used in chemical catalysis. Their practical performance can be better exploited through morphological control by adjusting the synthetic strategy. Herein, a photochemical synthesis route was used to achieve the controlled preparation of bimetallic Au/Ag BNps. Size and shape control is achieved depending on the type of initiating radical therefore synthesized new one-component Type II photoinitiator, namely 2-thioxanthone thioacetic acid-dioxide was employed for the synthesis of Au/Ag BNp both in solution and polymer matrix. The effect of the gold/silver ratio on the nanoparticle size, shape and distribution was investigated, and the characterization of the obtained nanoparticles was performed by UV–Vis spectrophotometry, DLS and SEM techniques. Additionally, photocatalytic oxidative degradation of methylene blue was achieved with the prepared Au/Ag bimetallic nanocomposite films. By evaluating the photocatalytic oxidation degradation of methylene blue under UV–Vis light irradiation, 2:1 ratio of Au/Ag nanoparticles containing nanocomposite film exhibit the best activity compared with other composition of Au/Ag. The size and high SPR absorption band are thought to be responsible for superior photocatalytic activity.

Formation of CdS/ZnS nanoparticles in polymer matrix by SILAR method: Experiments and exploring its optical properties with DDA calculations

Composite nanostructures of Cadmium Sulfide (CdS) and Zinc sulfide (ZnS) were formed within the Cellulose Acetate matrix using successive ionic layer adsorption and reaction (SILAR) method, and their morphological and elemental characterizations were done employing field emission electron microscopy (FESEM) and energy dispersive X-ray (EDX) analyses. Experimental and theoretical investigations of the optical absorbance spectra of the prepared samples were performed by Uv-Visible spectroscopy and discrete dipole approximation (DDA) calculations respectively. The results show that when the absorbing part of the polymer matrix is composed of only CdS, increasing the number of SILAR cycles results in enlarging the absorbing part and a redshift in the wavelength of the maximum of the absorbance spectra. On the contrary, when the two materials CdS and ZnS have a contribution in the formation of the absorbing part, without paying attention to material distribution topology, and the absorbing part size, the abovementioned wavelength will remain unchanged.

Dispersion of nanoparticles in optically transparent polymer matrices

Search and analysis of results of theoretical and experimental studies, materials of dissertations, literature sources and patents in the field of optical and optoelectronic instrumentation were carried out. Obtained data and recommendations on the development of methods for dispersing nanoparticles into polymer matrices for the creation of optically transparent nan composites for use in many fields of science and technology are generalized. Analysis of considered results makes it possible to conclude that for creating hybrid organic-inorganic composites with high level of dispersion of inorganic component, it is necessary to solve problems relating to compatibility of components and stabilization of filler nanoparticles in polymer matrix. Due to the limited range of hydrophilic polymers capable of forming composites with nanoparticles without stabilizers, the main approaches to the preparation of hybrid composites are using modifying additives of surfactants, as well as complex chemical reactions on the surface of inorganic filler nanoparticles. Such methods of obtaining nanocomposites with nanoparticles are laborious and involve formation of by-products and additional purification. It is shown that titanium dioxide (TiO2) and zinc oxide (ZnO) are of great interest among a large number of nanodispersed fillers of polymer matrices in preparing composite materials. There are many methods for synthesis of ZnO and TiO2 nanoparticles with various shapes and sizes, including laser ablation method, which is convenient and universal method for preparing nanosuspensions of solid-phase materials in liquid. Advantages over other methods for nanoparticle synthesis, such as the simplicity of method, environmental friendliness, low cost, and the ability to obtain cleaner colloidal solutions without using surfactants and other impurities, have made laser ablation in a liquid medium very popular among researchers.

Metal incorporated Philippine Abaca fiber (Manila hemp) as a potential novel filter for water disinfection

The contamination of water sources by pathogenic bacteria poses a threat both in the environment and in human health. The incorporation of metal nanoparticles in polymer matrix which is abundantly available in a country can be improved to enhance its antimicrobial property. This study was focused on the development of a novel antibacterial water filter from synthesized silver-copper nanoparticles (Ag-CuNPs) incorporated into Philippine abaca fiber (Manila Hemp). Pre-treatment method and determination of adsorption capacity of abaca fiber towards metal ions, Ag+ and Cu2+ were done prior to synthesis of Ag, Cu and Ag-Cu nanocomposites. Alkali treatment of the fiber confirms OH, C-O and C=O of a cellulose, pectin and lignin in the FTIR analysis. These groups effectively altered the nature of the abaca fiber to hydrophobic, thus, increasing its adsorption capacity up to 80%. Morphological and structural properties of the formed nanoparticles were confirmed using scanning electron microscopy (SEM) revealing polymeric matrices of the fiber in the particle size of 80 nm – 100nm. UV-Vis spectra revealed a broadening of the absorption spectra of a bimetallic Ag-Cu nanoparticles at 410 nm. The antimicrobial assay results revealed promising synergism of the combined silver and copper nanoparticles against both Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) bacterial strains in synthetically prepared water. Also, a relatively proximate bactericidal efficiency was attained between the CuNPs and Ag-CuNPs abaca fiber composites. The developed Ag-CuNPs abaca fiber composite can act as novel antibacterial water filter for water disinfection.

Synthesis and characterization of polypyrrole-Ce0.05CoSb3 nanocomposites

Filled Skutterudite CeyCoSb3 (y = 0.05) nanoparticles synthesized by Solvothermal method are incorporated into conducting Polypyrrole (PPy) via in-situ Chemical Polymerization technique to form Polymer Inorganic Nanocomposites (PINs). Further, studies on different weight percent (10, 20, 30 and 40%) of the nanocomposites with respect to pure PPy are conducted. Field Emission Scanning Electron Microscopy (FESEM) equipped with Energy Dispersive X-Ray Spectrometer (EDS), powder X-Ray Diffractometer (pXRD), Fourier Transform Infrared (FTIR) Spectroscopy techniques were employed to study morphological, structural and optical properties of as-synthesized PINs. FESEM confirms uniform distribution of nanoparticles in polymer matrix and increase in atomic weight % of CeyCoSb3 (y = 0.05) shown in EDS analysis confirms the successful fusing of nanoparticles into the PPy chains. pXRD analysis justifies the formation of PPy-Ce0.05CoSb3 nanocomposites indicating the presence of Ce0.05CoSb3 diffraction peaks with broad amorphous background of polypyrrole. FTIR spectra reveal the vibrational modes and the chemical bonds of pure PPy and PPy fused with Ce0.05CoSb3 justifying the formation of expected nanocomposites.

Electric properties of Ni-C and Co-C core–shell nanoparticles in polymer matrix

A number of the nanocarbon-metal Ni x -C and Co50-C core–shell structures were obtained from phenol-formaldehyde resin as a carbon precursor using a mechanochemical method and pyrolysis at 1034 °K. The morphology of the obtained core–shell structures was characterized by scanning electron microscopy. The magnetic hysteresis loops of Ni25-C and Co50-C core–shell structures were investigated by using a vibrating sample magnetometer. The work presents the results of investigations of electrical resistivity of nanocarbon-metal Ni x -C and Co50-C core–shell structures embedded in polyvinyl acetate (PVA). Electrophysical properties of the composite materials (CMs) have been studied in a wide temperature range: 77–293 K. It was found that morphology and composition (the content of the metal phase and its relation to the carbon phase) of Ni x -C core–shell structures embedded in PVA influences the value of electrical resistivity, its temperature dependence ρ(Т) and δρ/ρ parameter of composites. The materials with the higher content of core–shell structures (Ni75-C and Co50-C) are characterized by the lower electrical resistivity, while the materials with the significant content of separate carbon phase in the form of nanotubes are characterized by the weaker ρ(Т) dependence.

Surface modification of zinc oxide nanoparticles by vinyltriethoxy silane (VTES)

Zinc oxide (ZnO) nanoparticles are hydrophilic in nature and difficult to disperse in polymer matrix due to agglomeration behavior. To disperse the zinc oxide nanoparticles in polymer matrix, it is necessary to modify their surface with hydrophobic groups such as silanes or surfactants. In this article, zinc oxide nanoparticles were modified with various concentration of vinyl triethoxysilane (VTES). To investigate the effect of different concentrations of VTES, on surface modification of zinc oxide nanoparticles, these were characterized using physical characterization techniques such as Fourier-transform infrared spectroscopy (FTIR), thermo-gravimetric analysis (TGA), scanning electron microscopy (SEM), Energy Dispersive X-rays Spectroscopy (EDX), X-ray diffraction (XRD) and contact angle. The results of FTIR, TGA, SEM, EDX and contact angle confirm the surface modification of zinc oxide nanoparticles by VTES. The XRD results show that the crystalline behavior of ZnO nanoparticles was not changed after surface modification by VTES. The crystallite size of surface modified ZnO nanoparticles was calculated using Debye-Scherrer equation and it was found approx 20 nm. In FTIR results, some new peaks at 1409, 1014 and 970 cm−1 were observed as compare to unmodified zinc oxide nanoparticles. In contact angle analysis, it was observed that the surface modified zinc oxide nanoparticles have very high contact angle (greater than150°) in comparison with hydrophilic behavior of unmodified zinc oxide nanoparticles. SEM analysis also showed the improved dispersity of ZnO nanoparticles. Based on characterization results, it was observed that the 15 wt% VTES concentration is suitable to carry out surface modification of ZnO nanoparticles.

Polymer Based ZnO–SiO2 Nanocomposite Flexible Sheets as High Dielectric Materials

Flexible dielectric polymer nanocomposites (NCs) with high dielectric permittivity and low loss factor have numerous applications in light emitting and storage devices. In this research work, polymer based NCs in the form of flexible sheets containing 5% ZnO and 15, 20% SiO2 nano-fillers, are synthesized by using co-precipitation method. X-ray diffraction analysis reveals the development of various diffraction planes related to ZnO and SiO2 phases confirms the synthesis of polycrystalline PB–ZnO–SiO2 NCs flexible sheets corresponding to various compositions. Morphology and compositional analysis show the uniform distribution of nanoparticles in polymer matrix with estimated elemental contents in each composition. Dielectric measurements demonstrate a sharp increase in dielectric permittivity with relatively low dissipation factor in synthesized compositions having ZnO and SiO2 nano-fillers. The static value of dielectric constant at 100 Hz is found to be 10.79 for sample having 20% SiO2 nano-fillers that is 3.4 times greater than pure PVA and it shows relatively low value of dissipation factor. The observed AC conductivity of synthesized NCs flexible sheets having 5% ZnO, 20% SiO2 nano-fillers is 2.15 × 10–5 S/m that is 3.3 times greater than pure PVA at 1 × 106 Hz. Complex impedance spectroscopy further confirms, these materials as promising candidates for better capacitive performance.

Poly(Butylene Terephthalate) Filled with Sb2O3 Nanoparticles: Effects of Particle Surface Treatment, Particle Size, Particle Morphology and Particle Loading on Mechanical Properties of Composites

Poor dispersion of nanoparticles in polymer matrix would limit the development and application of particulate-filled polymer composites. Therefore, the Sb2O3 nanoparticles were functionalized by a combination of cetyltrimethyl ammonium bromide (CTAB) and silane coupling agent KH-560 via water bath modification method so as to improve the dispersion of Sb2O3 nanoparticles in poly(butylene terephthalate) (PBT) matrix and enhance the interfacial adhesion between nanoparticles and polymer matrix. Besides, the coating efficiency of compound modifiers on the surface of Sb2O3 nanoparticles was characterized by Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA). The Sb2O3 nanoparticles with different morphologies were systemically measured using transmission electron microscopy and dynamic light scattering measurement. The effects of particle surface treatment, particle size, particle morphology and particle loading on mechanical properties of composites were studied by the X-ray diffraction (XRD), tensile test machine and impact strength machine. The tensile strength of nanocomposites gradually increases with decreasing the particle size at the same amount of Sb2O3 nanoparticle fillers, which is attributed to improvement of interfacial contact area and stronger interfacial adhesion between Sb2O3 nanoparticles and PBT matrix. And the compound modified Sb2O3 nanoparticles are homogeneously dispersed in PBT matrix and play an important role in the properties enhancement. Moreover, taking consideration of the tensile and impact strengths, the optimal loading is 3 wt%.