Filler In Poly Research Articles

Interfacial polarization regulation of ultrathin 2D nanosheets inducing high energy storage density of polymer-based nanocomposite with opposite gradient architecture

High discharge energy density (Udis) has been achieved via regulating the interfacial polarization of ultra-thin 2D Sr2Nb2O7 nanosheets (SNO NSs) and constructing opposite gradient architecture. To further increase the dielectric constant (εr) of SNO NSs and therefore motivate high interfacial polarization, core-shell structured 2D nanosheets include Sr2Nb2O7@TiO2 NSs and Sr2Nb2O7@BaTiO3 NSs are successfully prepared and utilized as fillers in poly(vinylidene fluoride) (PVDF)/ polymethyl methacrylate (PMMA) blend polymer matrix (BPM). In addition, opposite gradient architecture, include high polarization layer (PL), high insulating layer (IL) filled with large size BN nanosheets (BN NSs) and middle transition layer, are constructed to depress the electric breakdown strength (Eb) degradation. As expected, the SNO@BTO NSs filled films with an optimal composition achieve excellent Udis of 32.51 J cm−3 with charge-discharge efficiency (η) of 0.64 near the Weibull Eb of 651.52 MV m−1. This Udis value is the most prominent in dielectric polymer nanocomposites under equivalent applied electrical field. The opposite gradient architecture can effectively depress the Eb degradation by preventing the electric trees evolution, which is confirmed by finite element simulations. This work provides a novel paradigm to fabricate high Udis energy storage polymer-based nanocomposites filled with 2D nanofillers.

Synthesis and Physicochemical Properties of Poly(vinyl) Alcohol Nanocomposites Reinforced with Nanocrystalline Cellulose from Tea (Camellia sinensis) Waste.

The purpose of this study was to utilize cellulose from tea waste as nanocrystalline cellulose (NCC), which is used as a filler in poly(vinyl) alcohol (PVA) nanocomposites. To obtain the NCC, a chemical process was conducted in the form of alkali treatment, followed by bleaching and hydrolysis. Nanocomposites were formed by mixing PVA with various NCC suspensions. With chemical treatment, lignin and hemicellulose can be removed from the tea waste to obtain NCC. This can be seen in the functional groups of cellulose and the increase in crystallinity. The NCC had a mean diameter of 6.99 ± 0.50 nm. Furthermore, the addition of NCC to the PVA nanocomposite influenced the properties of the nanocomposites. This can be seen in the general increase in opacity value, thermal and mechanical properties, and crystallinity, as well as the decrease in the value of the swelling ratio after adding NCC. This study has revealed that NCC from tea waste can be used to improve the physicochemical properties of PVA film.

Three-way evolved gas analysis-mass spectrometry combined with principal component analysis (EGA-MS-PCA) to probe interfacial states between matrix and filler in poly(styrene-b-butadiene-b-styrene) (SBS) nanocomposites

We have developed a three-way evolved gas analysis-mass spectrometry technique combined with principal component analysis (EGA-MS-PCA) to probe the interfacial state between matrix and filler in poly(styrene-b-butadiene-b-styrene) (SBS) nanocomposites containing graphene nanoplatelets (GNPs). Although the peaks arising from the polystyrene and polybutadiene components present in the system were readily captured, the different patterns of peak intensities, which vary according to the applied temperature and GNP content, make interpretation of the data difficult. The data sets are thus subjected to mathematical decomposition based on principal component analysis (PCA) to selectively derive essential information. The EGA-MS-PCA process reveals that the inclusion of GNPs essentially works to restrict the decomposition of the polystyrene component in the SBS sample, mostly indicating the formation of a π–π stacking interaction between the SBS and GNPs. This observation, in turn, provides in-depth understanding that is likely to lead to stiffness of SBS by incorporation of GNPs.

Enhanced energy density in sandwich-structured P(VDF-HFP) nanocomposites containing Hf0.5Zr0.5O2 nanofibers

Ceramic/polymer composites with high energy density attract great interest due to their application in micro-electric power systems. However, the large permittivity mismatch between ceramic fillers and polymer matrix will largely decrease the breakdown strength and energy density of nanocomposites. Herein, one-dimensional Hf0.5Zr0.5O2 nanofibers (HZO-NFs) with very low permittivity were proposed as the loading fillers in poly (vinylidene fluoride - hexafluoro propylene) (P(VDF-HFP)) copolymer for energy-storage applications for the first time via a simple scalable method of electrospinning technique. P(VDF-HFP) nanocomposites with 3 wt% HZO-NFs (3 wt% HZO/P) showed a high discharged energy density (Ud) of 13.68 J/cm3 with a high breakdown strength (Eb) of 508.66 kV/mm. Sandwich-structured P-3 wt% HZO/P-P nanocomposite achieved an excellent Ud of 21.63 J/cm3 and a high η of ∼ 65.68% at ultrahigh Eb of 706.71 kV/mm, which are much higher than those of the commercial BOPP, i.e. 2 J/cm3 at 640 kV/mm. Moreover, the COMSOL simulations revealed that the introduction of 1D nanofibers and charge traps could effectively improve the local distribution of electric field, and finally increased the breakdown strength. The major contribution to the improved Ud originates from the large breakdown strength (4 ∼ 8 MV/cm), because of the large band width of HZO and the existence of multi-interfaces. This work can provide a new perspective for promoting the performance of polymer nanocomposites.

Photopolymerization of Pollen Based Biosourced Composites and Applications in 3D and 4D Printing

AbstractPollen have the potential to be effective plant‐based biorenewable reinforcing fillers for polymers due to their chemical stability and unique micro‐ or nano‐structured surfaces. Pollen‐polymer composites can form the basis for a new class of light‐weight and sustainable materials if compatible polymer‐filler systems can be engineered through photopolymerization, but this idea is previously unexplored. The first demonstration of photopolymerization and 3D printing with the incorporation of pine pollen as filler in poly(ethylene glycol) diacrylate are presented. The filler properties affecting the related depth of cure and the mechanical, thermal, and functional properties are examined in detail. In addition, the lithography technique is applied to the photocomposites for the production of 3D patterns. 4D printing behavior is also possible through the water swelling and dehydration induced actuation of the 3D printed composites with spatial resolution features. This work is expected to provide a new way to a field for photopolymerization reactions in natural material‐resin composites and thereby to expand potential applications in 3D and 4D printing.

Polypyrrole‐aided surface decoration of graphene oxide nanosheets as fillers for poly(ether‐ b ‐amid) mixed matrix membranes to enhance CO 2 capture

Polypyrrole‐aided surface decoration of graphene oxide nanosheets as fillers for poly(ether‐ <i>b</i> ‐amid) mixed matrix membranes to enhance <scp> CO ₂ </scp> capture

Bio‐Based Poly(3-hydroxybutyrate)/Thermoplastic Starch Composites as a Host Matrix for Biochar Fillers

Biochar is an excellent, but less-used candidate to serve as an alternative filler in poly(3-hydroxybutyrate) (PHB)-based composites. Increasing amounts of biochar between 20 and 50 wt% were incorporated in PHB/char and PHB/thermoplastic starch (TPS)/char composites and its effects on the microstructure, crystallization and thermal properties were investigated. PHB shows a significant reduction in molecular weight after processing and the increasing amounts of biochar decreases this even stronger. From thermogravimetric analysis, it was clear that the onset degradation temperature of the PHB/char composites (255 °C) is only slightly influenced by the biochar particles up to 40 wt%. Contrastingly, this temperature reduces to 245 °C when 50 wt% of biochar is added. Additional data confirm that morphology and crystallization kinetics are enhanced up to 40 wt% of biochar, while even higher percentages of filler clearly have an opposite effect. Finally, this work reveals the ability of TPS to work as an excellent intermediator between biochar and PHB at biochar concentrations up to 20 wt%, where degradation and resulting reduction in molecular weight remains limited as compared to that of the PHB/char sample. Furthermore, like biochar, TPS acts as a nucleation agent in the composites and removes the influence of the biochar on the thermal stability of the composites.

Hydroxylated BiFeO3 as efficient fillers in poly(vinylidene fluoride) for flexible dielectric, ferroelectric, energy storage and mechanical energy harvesting application.

Here we report the effect of surface hydroxylation of BiFeO3 fillers on the dielectric, ferroelectric, energy storage and mechanical energy harvesting performance of poly(vinylidene fluoride). Surface hydroxylation helped to improve the interfacial interaction between the filler and PVDF matrix by introducing a strong hydrogen bonding between the -OH group of the hydroxylated BiFeO3 filler surface and the -CF2 dipole of PVDF in place of electrostatic interfacial interaction between non-hydroxylated BiFeO3 and the -CH2 dipole of PVDF. The amount of polar phase increased to around 91% for a 7 wt% hydroxylated BiFeO3 loaded PVDF film (7BFOH) by this new type of interfacial interaction. The dielectric, ferroelectric, energy storage and mechanical energy harvesting performance of the PVDF based composite films also improved by the above said technique. Upon repeated human finger tapping, the 7BFOH film delivered ∼18 V output peak to peak open circuit ac voltage (VOC). After rectification, the VOC of the 7BFOH film was able to charge a 10 μF capacitor up to ∼3 V which was able to light up some LEDs (connected in parallel) together instantaneously, which proved the real life applicability of the composite films in low power consuming self-powered electronic devices.

Polydopamine-Coated Garnet Particles Homogeneously Distributed in Poly(propylene carbonate) for the Conductive and Stable Membrane Electrolytes of Solid Lithium Batteries.

Flexible membrane electrolytes consisting of Li6.4La3Zr1.4Ta0.6O12 (LLZTO) fillers in poly(propylene carbonate) (PPC) are considered promising for developing solid lithium batteries with high energy density and safety. However, LLZTO particles tend to agglomerate owing to their high surface energy, especially concerning their distribution in PPC that has low surface energy. Moreover, basic LLZTO particles attack PPC, resulting in its decomposition. Such problems make it difficult to achieve membrane electrolytes of PPC/LLZTO with high conduction and stability. In this work, continuous polydopamine (PDA) layers with a thickness of 4 nm are coated on LLZTO particles. Characterized by synchrotron X-ray microtomography and scanning electron microscopy, the PDA-coated LLZTO particles show homogeneous dispersion in PPC, which is attributed to the reduced surface energy of the LLZTO particles. Besides, this coating hinders the reaction between LLZTO and PPC, which improves the chemical stability of the membrane electrolytes. Consequently, the cells based on membrane electrolytes with PDA-coated LLZTO particles in PPC show improved electrochemical performance and cycling stability. These results demonstrate that the strategy of coating basic LLZTO particles is powerful for enhancing their usability in the high-performance membrane electrolytes for solid lithium batteries.

Valorization of oat hull fiber from agri-food industrial waste as filler for poly(3-hydroxybutyrate-co-3-hydroxyhexanoate)

Oat hull fibers are an agri-food industrial waste used in this research as a filler for a poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) matrix, to obtain a fully bio-based polymer-matrix composite material. The compounding process was carried out with a twin-screw extruder, avoiding chemical solvents and employing a technology commonly used by the industrial field. Silanization procedure was run to improve the affinity between the matrix and the filler. Compounds were structurally, microstructurally, mechanically and thermally characterized. Results denote that also at 8 v/v%, oat hull fibers work not only as inert filler, but also they have a slightly improving effect on mechanical properties of neat biopolymer, increasing of almost 12% the Young’s modulus, without a loss in tensile elongation at break. Therefore, this research study is a noteworthy approach which reduces the material costs and PHBH volumes, while valorizing waste biomasses.

Graphitic-carbon nitride nanosheets as a new inorganic filler for improving energy storage density of PVDF-based dielectric composites

Graphitic-phase carbon nitride (g-C3N4) nanosheets with lateral size of 1000 nm, 500 nm, and 100 nm have been fabricated by a one-step thermal condensation method at different thermal treating temperatures and used as filler for poly(vinylidene fluoride) (PVDF)-based dielectric composites. The effects of its size and content on energy storage density of g-C3N4/PVDF composites are discussed. The experimental results show that the energy storage density of the composites containing 3 wt% g-C3N4 increases with the decrease of lateral size and could reach to 11.7 J cm−3 at 522 kV mm−1, much higher than pure PVDF of 5.8 J cm−3 at 386 kV mm−1. A finite element simulation is employed to describe electric field distribution within the composites and reveal further the role of g-C3N4 nanosheets on the energy storage behavior of the composites. This work provides a new inorganic filler for high energy storage density PVDF-based dielectric composites.

Biodegradable Poly (lactic acid)/ Poly (ethylene glycol) Reinforced Multi-Walled Carbon Nanotube Nanocomposite Fabrication, Characterization, Properties, and Applications.

This paper presents the electromagnetic interference properties of multi-walled carbon nanotubes (MWCNTs) as a novel nano-reinforcement filler in poly (lactic acid) (PLA)/poly (ethylene glycol) (PEG) polymer matrix that was prepared via melt blending mode. Plasticization of PLA was first carried out by PEG, which overcomes its brittleness problem, in order to enhance its flexibility. A waveguide adapter technique was used to measure the dielectric properties , and S-parameters reflection (S11) and transmission (S21) coefficients. The dielectric properties, microwave attenuation performances, and electromagnetic interference shielding effectiveness (EMISE) for all the material under test have been calculated over the full X-Band (8–12 GHz) due to its importance for military and commercial applications. The prepared samples were studied while using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), Fourier transforms infrared spectroscopy (FTIR), mechanical properties measurements, as well as thermogravimetric analysis (TGA). The results showed that the dielectric properties increased with increased multi-walled carbon nanotubes (MWCNTs) filler, as well as the shielding effectiveness of the MWCNT/PLA/PEG nanocomposites increased with the increasing of MWCNTs. The highest SE total value was found to be 42.07 dB at 12 GHz for 4 wt.% filler content. It is also observed that the attenuation values of the nanocomposites increased with an increase in MWCNTs loading, as well as the power loss values for all of the samples increased with the increase in MWCNTs loading, except the amount of the transmitted wave through the nanocomposites.

Multifunctional Carbon Nanotubes Enhanced Structural Composites with Improved Toughness and Damage Monitoring

The potential of carbon nanotubes (CNT) as multifunctional filler in poly(epoxy)-based structural composites has been investigated. In a first step the reinforcement effect of CNT has been studied by tensile and three points bending tests, which evidenced significant improvements of stress and strain at break (respectively +17% and +30% for tensile tests on unidirectional carbon fibre-epoxy composites). Moreover, fracture experiments have also revealed a positive effect of CNT on the toughness (G1c) of carbon fibres-epoxy composites (+105% of improvement at the initial stage). In a second step, the health monitoring capability quantum resistive strain sensors (sQRS) made of CNT filled epoxy nanocomposite, incorporated in the core of glass fibres-epoxy composites has been studied. It was shown that during cyclic tensile tests, following the evolution of the relative resistance amplitude (Ar) of sQRS with strain gives a pertinent information on non-reversible phenomena such as plastic deformation and cracks’ development within the composite. In particular, the evolution of the sQRS sensitivity (gauge factor GF) under and over the elastic limit, allows to track damage accumulation throughout the composite. These results suggest a possible use of sQRS for the structural health monitoring (SHM) of composites in fields such as boating, wind energy, aeronautics and automotive.

Polymers and cyclic compounds based on a side‐opening type cage silsesquioxane

ABSTRACTPolymers having polyhedral oligomeric silsesquioxane (POSS) in the main chains are an important class of organic–inorganic hybrid materials. Despite the increasing attention to the POSS polymers, variation of the monomers is still limited. Herein, we have proposed side‐opening POSS (SO‐POSS) monomers. Platinum‐catalyzed hydrosilylation polymerization proceeded to produce polysiloxanes having SO‐POSS in the main chains. The obtained polysiloxanes showed good solubility, high thermal stability, high transparency, and tunable reflective index. In addition, cyclic compounds were obtained during the investigation of the polymerization, and were synthesized with high selectivity under the slightly diluted conditions. The obtained cyclic compounds showed high thermal stability due to the silsesquioxane backbone, and the high dispersibility as a filler in poly(methyl methacrylate) was demonstrated. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 2243–2250

Enhanced dielectric and ferroelectric properties of cobalt ferrite (CoFe2O4) fiber embedded polyvinylidene fluoride (PVDF) multiferroic composite films

One-dimensional, ferromagnetic cobalt ferrite fibers were synthesized through electrospinning technique and were used as the fillers in poly(vinylidene fluoride) (PVDF) matrix to fabricate flexible, free-standing homogeneous PVDF/CoFe2O4 films. The structural properties of the composite films were analyzed through x-ray diffraction (XRD) whereas the functional groups were identified using FTIR studies, and a maximum enhancement of 76% of electroactive β-phase was observed with the incorporation of CoFe2O4 fibers. Morphological studies confirmed the formation of spherulites of diameter ranging from 5.2 to 15 μm. The roughness parameters of the PVDF/CoFe2O4 composite films were analyzed by atomic force microscopy (AFM). The variation in the dielectric constant and loss, and ferroelectric characteristics of the composite films at room temperature were investigated with respect to the fiber concentration. The enhanced dielectric constant of 29 with a tangent loss 0.21 was observed for 20 wt% filler loading at 100 Hz. The ferromagnetic nature of the composite films was analyzed with vibrating sample magnetometer (VSM), and the maximum saturation magnetization of 10.7 emu cm−3 was obtained for 20 wt% of the composite film. Further, the ferroelectric nature of the films was examined by the domain switching behavior using DC-EFM.

Poly(ε-caprolactone)-based biocomposites reinforced with nanocrystalline cellulose grafted with poly(L-lactic acid)

The modification of nanocrystalline cellulose with poly(L-lactic acid) was carried out using the “grafting from” approach based on the ring-opening polymerization of L-lactide initiated with cellulose hydroxyls. The modification was proved by FTIR spectroscopy, thermogravimetric analysis and dynamic light scattering. Samples of native and modified cellulose were applied as fillers for poly(ε-caprolactone) films that were studied for their mechanical properties. A significant increase of Young’s modulus was observed for composite material based on PCL containing nanocrystalline cellulose modified with poly(L-lactic acid).

Recycled Glass Fibres from Wind Turbines as a Filler for Poly(Vinyl Chloride)

This paper presents the method of using glass fibre with carbon deposit (GFCD), derived from the recycling of wind turbine blades, for production of composite materials based on poly(vinyl chloride) (PVC). Composite materials containing from 1 to 15 wt% of GFCD were produced by plasticising with a plastographometer and then by pressing. The processability and performance were studied. Mechanical properties in static tension, impact strength, and thermal stability were determined. Glass transition temperature was also determined by means of the dynamic mechanical thermal analysis (DMTA). The GFCD percentage of up to 15 wt% was found not to slightly affect the change in the processability, thermal stability, and glass transition temperature. PVC/GFCD composite materials are characterised by a definitely greater elastic modulus with simultaneous decrease of tensile strength and impact strength. An analysis with scanning electron microscopy revealed good adhesion between the filler and the polymer matrix.

Significantly Enhanced Electrostatic Energy Storage Performance of Flexible Polymer Composites by Introducing Highly Insulating‐Ferroelectric Microhybrids as Fillers

AbstractA hybrid nanoparticle, consisting of BaTiO3 nanoparticles tightly embedded in bronnitride (BN) nanosheets, has been fabricated based on a daring supposition that BN may act as a host to incorporate ferroelectric nanoparticles to improve insulation and polarization under a high electric field. Using the hybrids as fillers in poly(vinylidene fluoride) (PVDF) composites, a high electric breakdown strength (Eb ≈580 kV/mm), which is 1.76 times of the PVDF film, is obtained when the filler content is 5 wt%. A large displacement (9.3 µC/cm2 under 580 kV/mm) is observed so as to obtain a high discharged energy density (Ud ≈17.6 J/cm3) of the BT@BN/PVDF composites, which is 2.8 times of the PVDF film. The enhancement ratio of Eb achieved in this study demonstrates the highest among the reported results. This hybrid structure of fillers provides an effective way to adjust and improve the energy storage properties of the polymer‐based dielectrics.

The delayed degradation mechanism and mechanical properties of β-TCP filler in poly(lactide-co-glycolide)/beta-tricalcium phosphate composite suture anchors during short-time degradation in vivo

Abstract

On the Correlation of Lignocellulosic Filler Composition with the Performance Properties of Poly(\u03b5-Caprolactone) Based Biocomposites

In this work, three types of agricultural waste: olive stones (OS), date seed (DS) and wheat bran (WB) were applied as potential lignocellulosic fillers in poly(ε-caprolactone) (PCL) based biocomposites. Differences in composites’ performance were related to the higher content of proteins, noted for WB comparing to other fillers applied, which enhanced plasticization of PCL matrix. The mechanical properties of biocomposites were significantly affected by the agricultural waste fillers. Use of WB caused an obvious, even 25% decrease of tensile strength and hardness, which could be explained on account of glass transition temperature depletion and weaker matrix–filler interfacial interactions. Such phenomenon also increased water uptake of PCL/WB composites by more than 100%, while for PCL/OS and PCL/DS systems only for about 50%. Thermogravimetric analysis revealed that all investigated composites can be effectively processed without thermal decomposition. Generally, the outcome of this work demonstrated that OS, DS, and WB could be applied as promising lignocellulosic fillers used in manufacturing of high-performance polymer biocomposites.