Organic Fillers Research Articles

Acid-derived bacterial cellulose nanocrystals as organic filler for the generation of high-oxygen barrier bio-nanocomposite coatings

This study investigates the effect of the hydrolysis process on bacterial cellulose (BC) to obtain bacterial cellulose nanocrystals (BCNCs) used to create high oxygen barrier nanocomposite coatings for food packaging applications.

A Study on Applicability of Wood Flour Spacers Made from Woody Waste

Recently, the importance of wastepaper recycling has been emphasized and accordingly, several studies have been conducted to improve the quality of the Korean old corrugated container. A representative example is the application of wood flour-based organic fillers as the spacer. Therefore, if domestic woody waste, which is most commonly used as power plant fuels, can be applied to produce organic fillers, it is expected to become a new economic resource. In this study, we evaluated whether it is possible to manufacture wood flour from woody waste and use it as a spacer for papermaking. This study confirmed that if the wood flour made from woody waste is applied as the spacer for papermaking, the drying load can be reduced by the hydrophobic properties of lignin and securing bulk. In addition, from the analysis of the behavior of wood flour in the paper structure, the shape of the wood flour was found to bend after compression. Moreover, the wood flour was shown to adhere more flatly to the fibers or was located in-between, which minimized the interferences between fibers and stably increased the volume and the strength loss simultaneously. Based on the IR spectral analysis of the handsheets with wood powder being applied, it was confirmed that the intensity of the peaks weakened for the hydroxyl groups, such as OH bending and OH in-plane bending. Therefore, it can be concluded that the application of wood flour manufactured from unused forest resources can effectively increase the associated drying efficiency without chemical heterogeneity.

Preparation of Mixed Matrix Membranes Containing COF Materials for CO<sub>2 </sub>Removal from Natural Gas/Review

Gas separation membranes are one of the most important processes in purifying natural gas. CO2 reduction of natural gas is essential for purifying the gas and increasing its calorific value. A covalent organic framework (COF) has been developed as a filler in mixed-matrix membranes (MMM) to separate gases. COF materials were chosen because of their economical rate, good thermal and chemical stability, and flexible microporous structure. Mixed matrix membranes (MMMs) have received significant interest for their improved permeability and selectivity in natural gas purification. The results of using COF combined with other chemicals added to MMM. It has been observed that CO2 permeability increases as the COF content in the MMM increases, which enhances the gas-separation performance of the MMM. This review evaluated and analyzed the current scientific and the technical breakthroughs in developing MMMs, especially the unique type of organic fillers, which has been the basis of numerous new research for CO2 separation.

Vacuum 3D printing of highly filled polymeric matrix composites

In this contribution, we have investigated how polymeric matrix composites for aerospace applications are affected, when fabricated at low pressure, by the additive manufacturing process. Commercial filaments have been selected based on their representativeness of materials derived from lunar resources. Standard samples of thermoplastic polymers reinforced by organic fibers and inorganic fillers have been printed inside a vacuum chamber, and their mechanical and thermal properties have been characterized and discussed based on the printing conditions. The reported study represents a preliminary investigation of the potential applicability of the 3D printing technology on highly filled polymers for extraterrestrial applications.

ОСОБЛИВОСТІ ВПЛИВУ ЕПОКСИДОВАНОЇ СОЄВОЇ ОЛИВИ НА ВЛАСТИВОСТІ ПОЛІЛАКТИДНИХ МАТЕРІАЛІВ

Polylactide composite materials with the plasticizer-compatibilizer epoxidized soybean oil, which are filled with organic filler starch and inorganic – calcium carbonate, have been developed. Based on instrumental methods of analysis, the influence of epoxidized soybean oil on the features of physicochemical interactions in the system was investigated. A change in the rheological and thermophysical properties of the developed polylactide materials was established depending on the component composition.

Research on Microstructure and Mechanical Properties of Nylon6/Basalt Fiber/High-Density Polyethylene Composites.

As a representative polyolefin, high-density polyethylene (HDPE) has become one of the most commonly used commercial plastics with a wide range of applications in the world. However, its applications are limited due to poor mechanical properties. Hence, it is indispensable to develop composites with improved mechanical properties to overcome this disadvantage. In our work, basalt fiber (BF) and polyamide 6 (PA6)-reinforced HDPE composites were prepared. The effects of adding fiber, organic filler, and polar component maleic anhydride (MAH) on the microstructural characteristics of composites were investigated. Microstructural characterization evidenced that the binary-dispersed phase (PA6/BF) possesses a core-shell structure in which the component PA6 encapsulates the component BF, and the extent of encapsulation declines with the increase of MAH addition. It has been confirmed by scanning electron microscopy (SEM) observation that the microstructure is related to the interfacial tension of components. The effects of multicomponents on the crystallization behavior of composites were studied. The differential scanning calorimeter (DSC) analysis exhibited a significant change in the HDPE microstructure. Results showed that, as nucleating agents, PA6 and BF improve the crystallization rate in the cooling process. Furthermore, the rheological behavior of multicomponent composites was studied. With the increase of MAH, a clear improvement of complex viscosity and storage modulus was observed, of which the mechanism has been discussed in detail. The relationship between microstructure and heat resistance of composites was studied by a thermal deformation test under static fore. It is confirmed that the thermally conductive fiber BF and other components can form a thermally conductive network and channels, thus improving the heat resistance. It can become a composite material, which is suitable for special environments.

Preparation of Low Volatile Organic Compounds Silver Paste Containing Ternary Conductive Fillers and Optimization of Their Performances.

Conductive silver paste is a key material in the fields of printed circuits and printed electronic devices. However, the preparation of conductive silver paste with low-cost and volatile organic compounds (VOCs) is still a challenge. In this work, conductive silver pastes with excellent comprehensive performances were developed by using water-borne polyurethane (WPU) as the bonding phase and using the ternary mixture of Ag microflakes (Ag MFs), Ag nanowires (Ag NWs), and Ag nanoparticles (Ag NPs) as the conductive phase. WPU endowed conductive silver pastes with the adhesion along with releasing a few VOCs during the curing. Results showed that a small amount of Ag NPs or Ag NWs dramatically enhanced the electrical conductivity of silver paste paint film filled only with Ag MFs. The electrical resistivity for optimal ternary mixture conductive silver paste was 0.2 × 10-3 Ω∙cm, and the conductive phase was composed of 20.0 wt% Ag MFs, 7.5 wt% Ag NWs, and 2.5 wt% Ag NPs. Meanwhile, the adhesive strength and hardness of silver paste paint film were effectively improved by increasing the curing temperature. The optimal overall performance of the conductive silver pastes was achieved at the curing temperature of 160 °C. Therefore, this work can provide a new route for preparing conductive silver pastes with high performances.

Technical Surfactant Effect on Precipitation Method of Glutinous Rice Flour Filler Size Reduction

Most of the materials used in dentistry contain fillers as part of their composition to modify their chemical and mechanical properties. Filler size reduction needs economic and environmentally friendly materials to control the viscosity on a simple precipitation method using surfactant. Technical surfactants with more affordable prices also could develop filler size reduction. The study aims to analyse different technical surfactant effects on the glutinous rice flour precipitation method of filler size reduction used as an organic filler in dental applications. Precipitation technique is used by preparing the mixture by adding glutinous rice solution of bi-distilled water or sodium hydroxide with different 4% technical surfactant (Span 80 and Tween 80) dropwise to absolute ethanol. Samples were centrifuged at 3000 and 6000 rpm, then washed and characterized using Scanning Electron Microscope (SEM), Fourier Transform Infra-Red (FTIR), X-ray Diffraction (XRD), and Dynamic Light Scattering (DLS). As the result of this study, a size reduction of 714.8 nm with spherical and rod-like shapes could be generated from glutinous rice flour with the addition of Span 80 technical surfactant in 3000 rpm centrifugation speed for organic filler materials using sodium hydroxide solvent. This study suggested an opportunity for the country’s available source improvement in determining dental materials viscosity and its reinforcement.

Synthesis and characterization of biocomposites based polypropylene/thermoplastic starch- reinforced with natural STIPA TENACISSIMA fibers and PP-g-MA

The current work aims to develop environmentally friendly plastic materials by preparing a composite polypropylene/thermoplastic starch (PP/TPS) using a melt-compounding process. In order to improve the compatibility of the two naturally incompatible polymers, natural Stipa tenacissima fibers treated on their surfaces and polypropylene (PP) pellets grafted with Maleic Anhydride (MA) were added to the mixture (PP and TPS). The mixture was then prepared using the melt-mixing method in various concentrations. X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA)/Differential thermal analysis (DTA), and mechanical tensile tests were then used to characterize the various formulations. SEM images revealed that the addition of (PP-g-MA) and natural fibers resulted in good starch plasticization and higher thermoplastic starch dispersion in the polypropylene matrix. It was also discovered that increasing the TPS concentration over the PP concentration tends to reduce the mechanical tensile properties. However, the composite with 15% TPS had the best mechanical properties. The thermogravimetric analysis (TGA) results revealed that the organic filler used acted as a reinforcing agent, increasing the thermal stability of the polypropylene/thermoplastic starch (PP/TPS) compound.

Functionalized POSS-Modified SEBS-Based Composite Anion-Exchange Membranes for AEMFCs

Inspired by the strategy of rubber reinforcement, the N-methylpiperidium functionalized POSS was designed and synthesized to improve the ion conductivity as well as the mechanical and thermal properties of SEBS-based anion-exchange membranes (AEMs). A series of Pi-POSSx%/Pi-SEBS AEMs were prepared and assembled into MEAs for the fuel cell performance test. The addition of Pi-POSS fillers significantly enhanced the comprehensive performance of the AEMs. Especially, the Pi-POSS15%/Pi-SEBS composite membrane with the highest IEC value exhibited ion conductivities of 30.70 mS cm–1 at 30 °C and 69.11 mS cm–1 at 80 °C and the best alkaline stability. The Pi-POSS15%/Pi-SEBS composite membrane showed a maximum power density of 219 mW cm–2 at 80 °C, which was higher than the original Pi-SEBS membrane (117 mW cm–2). This work discloses a promising approach for improving the AEM performance with well-designed inorganic–organic composite fillers.

Electric field‐assisted preparation of PANI/TPU all‐organic composites with enhanced dielectric permittivity and anisotropic optical properties

AbstractTo meet the demands of multifunctional applications, developing functional composites with excellent properties (such as high dielectric permittivity, good mechanical properties, and anisotropic optical transmittance) is urgent. In this regard, preparing composites with all‐organic components is a promising strategy. Herein, we demonstrated a simple and time‐saving method for assembling and aligning polyaniline (PANI) particles in the TPU matrix by an AC electric field. The alignment of PANI in the polymer matrix not only obviously enhances dielectric permittivity but also effectively increases optical anisotropy. At the same filler loading content, the dielectric permittivity of aligned composites prepared under 10 Hz electric fields is 10.63 (10−1 Hz), which is higher than the dielectric property of random composites (8.58). The kinetics of aligning process of PANI particles are systematically studied by in situ optical microscope while an AC electric field is applied. We believe that this research work provides a potential solution to increase both dielectric permittivity and optical anisotropy of composites by the alignment of organic fillers via an electric field, which is essential for future flexible wearable electronics.

Spent-coffee grounds as a zero-burden material blended with bio-based poly(butylene succinate) for production of bio-composites: Findings from a Life Cycle Assessment application experience

This paper was conceived in consideration of the emerging trend of the composite industry's transition into organic filler application in materials and exploitation of organic wastes, to draw attention to the case of spent coffee grounds (SCG), namely the solid waste resulting from the popular beverage coffee. Life Cycle Assessment (LCA) analysis of SCG has been mainly focussed on oil extraction, which fails to address the value-added potential of solid waste and does not address the full life cycle of coffee. The study discussed in this paper aims at exploring the Carbon Footprint (CF) and the Cumulative Energy Demand (CED) of a set of composites through the application of LCA on a lab-scale dimension, which is comparable to small start-up production levels. Using the previously proven concept of the melt-blended SCG and bio-based poly (butylene succinate) (PBS) composites, the authors assessed a range from 20 to 60 wt% filler content suitable for a large variety of applications. Results from the study proved that the SCG/PBS ratio increased from 0.25 to 1.5 and reduced the whole-system related CED and CF by 7.4–8.4%. Overall, the study allowed to understand that, already in the phases of lab-scale design, testing, and assessment, it is possible to find material recovery paths that have the potential to lead to implementing sustainable circular models of the economy.

Development and optimization of lattice structure on the walnut shell reinforced PLA composite for the tensile strength and dimensional error properties

The organic fillers and honeycomb lattice structure intruded novel bio-composite materials for the 3D printing application is a practical and eco-friendly approach for developing lightweight biopolymeric components. The present work investigates the impact of incorporation of hexagon lattice structure on the walnut shell/PLA polymeric composite material using the Fused Deposition Modelling method. The printing process parameters such as nozzle temperature, layer height, infill density, and printing speed are varied to optimize the tensile and dimensional area error properties. Taguchi optimization technique is employed to find the optimal printing condition for the effective experimental output responses. The results from the experiments clearly show that the maximum tensile strength of 2.684 MPa was observed on the optimized printing condition of nozzle temperature of 210℃, a layer height of 0.1 mm, an infill density of 100 %, and a printing speed of 20 mm/sec. The developed mathematical model from the regression analysis depicted the R-square value concerning the output responses like tensile strength will be 92.24, and dimensional area error will be 87.48. It proclaims that; the model is fit for the large-scale production of the hexagon lattice structure in the walnut shell/PLA composite. Furthermore, the macrographs of the tested composites fabricated at higher infill density exhibited lower sidewall edge failure than the samples fabricated at the lowest infill density percentages.

The influence of accelerated aging on selected mechanical properties of polypropylene with organic fillers

The aging effect aging in water at the temperature of 100±2°C on selected mechanical properties of polypropylene with organic fillers (hemp chaff, a mixture of oak, birch and maple leaves) was investigated. A significant influence of the aging process on the impact strength and elongation at break was observed. The degradation processes were also visible on the surface of the samples.

Functionalized organic filler based integrated membranes for environmental remediation.

Mixed matrix membranes (MMMs) are synthesized for efficient CO2 separation released from various anthropogenic sources, which are due to global environmental concerns. The synergetic effect of porous nitrogen-rich, CO2-philic filler and polymer in mixed matrix-based membranes (MMMs) can separate CO2 competent. The development of various loadings of porphyrin poly(N-isopropyl Acryl Amide) (P-NIPAM)as functionalized organic fillers (5-20%) in polysulfone (PSU) through solution casting is carried out followed by the various characterizations including field emission scanning electron microscopy (FESEM), X-ray diffraction analysis (XRD), Fourier Transform Infrared Spectrometer(FT-IR) analysis and pure and mixed gas permeations ranging from 2 to 10bar feed pressure. Due to both organic species interactions in the matrix, well-distributed fillers and homogenous surfaces, and cross-sectional structures were observed due to π-π interactions and Lewis's basic functionalities. The strong affinity of porous nitrogen-rich and CO2-philic fillers through gas permeation analysis showed high CO2/CH4 and CO2/N2 gas performance that surpassed Robeson's upper bound limit. Comparatively, MMMs showed improved CO2/CH4 permeabilities from 87.5±0.5 Barrer to 88.2±0.9 Barrer than pure polymer matrix. For CO2/N2, CO2 permeabilities improved to 75±0.8 Barrer than pure polymer matrix. For both gas pairs (CO2/CH4, CO2/N2), respective pureselectivities (84%; 86%) and binary selectivities (85% and 85%)were improved. Various theoretical gas permeation models were used to predict CO2 permeabilities for MMMs from which the modified Maxwell-Wagner-Sillar model showed the least AARE% of 0.87. The results showed promising results for efficient CO2 separation due to exceptional functionalized P-PNIPAM affinitive properties. Finally, cost analysis reflected the inflated cost of membranes production for industrial setup using indigenous resources.

Bio-composites and bio-hybrid composites reinforced with natural fibers: Review

The need to adapt to sustainable development, green chemistry, and industrial ecology, which appear later, leads to the development of new materials. Among this new generation of materials are composites that are characterized by high performance. Several types of research are studying the evolution of bio-composites to obtain efficient and less expensive products, especially since the availability of petroleum and conventional materials seem to be exhausted, and their cost is high. This literature review presents a summary of bio-composite materials reinforced with natural organic and inorganic fillers. Besides, it describes the bio-hybrid composites materials with “natural/synthetic fibers” or with “natural fibers”. These materials with natural reinforcement have a great capacity to replace conventional composites thanks to their low cost, lightness, and ecological advantages. In addition, it reports an idea about the resources of natural reinforcements, as well as their mechanical and chemical properties and their application domains. Thus, the last part summarizes the modelling approaches.

Enhancement of SO2 high temperature depolarized electrolysis by means of graphene oxide composite polybenzimidazole membranes

In the present work, Polybenzimidazole-composite membranes with graphene oxide as organic filler with different contents (0.5, 1.0, 2.0 and 3.0 wt%) were prepared and tested in a sulfur depolarized electrolyzer. The composite Graphene Oxide/Polybenzimidazole membranes show greater electrolyzer performance than a standard membrane. For the first time, actual hydrogen production is reported at high temperature in the range of 110 °C–140 °C for the sulfur dioxide depolarized electrolysis. In general, composite Graphene Oxide/Polybenzimidazole membranes showed superior performance, obtaining the highest hydrogen generation with the composite membrane with a content of 2 wt%. Furthermore, sulfur dioxide crossover is reported to decrease by increasing the amount of graphene oxide into the membrane, demonstrating the benefit of adding Graphene Oxide to a Polybenzimidazole matrix for the sulfur dioxide depolarized electrolysis.

Advances in polybenzimidazole based membranes for fuel cell applications that overcome Nafion membranes constraints

High-temperature proton exchange membrane fuel cells (PEMFCs) are becoming more appealing to researchers around the world due to several advantages such as high energy conversion efficiency, lightweight due to the use of polymeric materials, low noise due to the lack of mechanical components, zero or low emission of harmful greenhouse gases, simple design, first reaction kinetics, and simple water management. The performance, limitations, and possibilities for the practical implementation of different high-temperature proton exchange membranes (PEMs) utilized in fuel cells are discussed in this review paper. A suitable PEM must be developed to improve the performance of membrane electrode assemblies for high-temperature PEMFCs (working temperature above 100 °C). Various PEMs such as sulfonated poly(ether ether ketone) (SPEEK), sulfonated polystyrene (SPS), sulfonated polyimide (SPI), sulfonated polysulfone (SPSU), phosphoric acid doped polybenzimidazole (PA-PBI), perfluorosulfonic acid (PFSA) polymer-based membranes have been investigated as PEMs for fuel cell applications by several research groups. Among the various PEMs, PA-PBI membranes are the most promising high-temperature PEM for fuel cell applications because of their higher proton conductivity at high temperatures and anhydrous conditions, good chemical and thermal, mechanical stability, and high durability. However, the performance of high-temperature PEMs based on pristine PA-PBI is insufficient to fulfill the need for practical implementation of high-temperature PEMFCs, which needs to be enhanced further before they can be used commercially. Therefore, PA-PBI composite membranes containing various multifunctional inorganic, organic, and hybrid fillers are being actively explored to produce high-temperature PEMs. The PA-PBI composite membranes’ proton conductivity increases with rising temperature and maintains conductivity in anhydrous conditions, as well as chemical, thermal, and oxidative stability under operating conditions and long-term performance stability.

<strong>Centrifugation effect on size distribution of organic dental filler made from glutinous rice flour</strong>

ABSTRACTIntroduction: Organic fillers made from the green-synthesis process can be utilized in dental treatment due to their non-toxic characteristic of the oral environment. Dental fillers must be smaller to improve their mechanical, physical, and biological properties. Material processing and centrifugation contribute to the size of processed materials. This study evaluates the effect of different centrifugation speeds on the size and distribution of glutinous rice flour as organic dental filler. Methods: This experimental study uses glutinous rice flour suspended in water and then centrifuged at different speeds of 3000 and 6000 rpm compared to untreated glutinous rice flour as control. The particle size was examined using Scanning Electron Microscope (SEM) and Dynamic Light Scattering (DLS). Next, Fourier Transform Infra Spectroscopy (FTIR) and X-ray Diffraction (XRD) were performed to evaluate whether there were structure and crystallinity changes. Finally, the cytocompatibility of fillers was examined by a cell viability test. Results: Centrifugation of glutinous rice flour at 3000 rpm resulted in smaller average size particles, evenly distributed, and higher crystallinity than other groups. There were no changes in functional groups, as shown by FTIR spectra. However, the processed samples were more amorphous compared to the control. Importantly, the processed samples appeared to be non-toxic, with a range of cell viability of 82.75-86.67% after 24 h incubation. Conclusion: Centrifugation speed of 3000 rpm has decreased in size, and a more homogenous particle size of organic filler made from glutinous rice flour. Importantly, it improved the cytocompatibility of particles compared to untreated control. Altogether, we proposed this organic material as a new potential material in the dental application that can be further investigated. Keywords: centrifugation speed; size distribution; organic dental filler; glutinous rice flour

Hemp Stem Epidermis and Cuticle: From Waste to Starter in Bio-Based Material Development.

Nowadays, hemp farmers are facing an urgent problem related to plant stem disposal after seed harvesting. In this work, the commonly discarded epidermis and cuticle of hemp stems were valorized, turning them towards a sustainable recycling and reuse, contributing to the circular economy concept. Cellulose deprived of amorphous regions was obtained by a green process consisting of an ethanolic ultrasound-assisted maceration followed by mild bleaching/hydrolysis. The obtained hemp cellulose was esterified with citric acid resulting in a 1.2-fold higher crystallinity index and 34 °C lower Tg value compared to the non-functionalized hemp cellulose. Green innovative biocomposite films were developed by embedding the modified cellulose into PLA by means of an extrusion process. The structural and morphological characterization of the obtained biocomposites highlighted the functionalization and further embedment of cellulose into the PLA matrix. Attenuated Total Reflectance–Fourier Transform Infrared spectroscopy (ATR-FTIR) results suggested physical and chemical interactions between PLA and the organic filler in the biofilms, observing a homogeneous composition by Field Emission-Scanning Electron Microscopy (FESEM). Moreover, some increase in thermal stability was found for biocomposites added with 5%wt of the hemp cellulose filler. The obtained results highlighted the feasible recovery of cellulose from hemp stem parts of disposal concern, adding value to this agro-waste, and its potential application for the development of novel biocomposite films to be used in different applications.