Filler Aggregates Research Articles

CoFe2O4-BaTiO3 Core-Shell-Embedded Flexible Polymer Composite as an Efficient Magnetoelectric Energy Harvester

Flexible magnetoelectric (ME) generators gained immense interest due to the broad applications in wearable and Internet of Things (IoT)-based devices. The key to achieving high energy conversion performance of 0-3 type ME composite films is the prevention of filler aggregation in the polymer matrix and accessing the full potential of intrinsic properties of filler. To achieve high performance, a flexible ME composite film was fabricated by homogeneous distribution of magnetostrictive CoFe2O4-BaTiO3 core-shell (CBCS) fillers into piezoelectric polyvinylidene fluoride (PVDF) polymer. The ME composite film generates an enhanced energy conversion efficiency by optimizing the shell thickness of CBCS and maximizing the electroactive β-phase at the BaTiO3 shell-PVDF interfacial region. The observed ME coefficient of the film reached up to 710 mV/cm∙Oe. Multiphysics simulations based on the finite element analysis were adopted to investigate the role of BaTiO3 shell thickness on the performance of ME film. This study paves the way to achieve higher filler loading content in the ME composite films to develop an efficient, flexible ME generator for eco-friendly permanent power sources.

Study on the Properties of All-Solid Waste Fluidized Filling Materials Applied to Mine Void Area Filling Engineering

The extraction of mining resources, as well as processing processes such as ore beneficiation and smelting, generate large amounts of tailings that are difficult to directly utilize. Meanwhile, substantial filling materials are required for the voids formed after mining operations, and the environmental issues and safety hazards brought on by massive solid waste disposal cannot be ignored. By utilizing solid waste with alkaline and pozzolanic activity as the binder component and gold tailings as filler aggregate to prepare filler material to fill up the void areas, the purpose of waste treatment can be achieved. In this study, salt sludge, steel slag, ground granulated blast furnace slag, and gold tailings were used to prepare all-solid waste fluidized filling material for filling mine void areas, which not only solves the engineering safety problem of easy collapse of the mine airspace in the mining process but also ensures a backfill effect with high strength, which continuously guarantees the uninterrupted progress of the mining project. At the same time, the preparation of fluidized materials can consume a large amount of tailings and other solid waste, solving the problem of their stockpiling. The components of the solid wastes used are all general industrial solid wastes, so the preparation of the fluidized materials will not have an impact on the surrounding environment. The effects of binder ratios on the workability of the filling materials were investigated by means of the slump and slump flow tests. Combined with the unconfined compressive strength test, the change in backfill material strength with curing age and the water–binder ratio was studied. The experimental results showed that the slump and slump flow value of the filling material were positively correlated with the water–binder ratio. The water–binder ratio range satisfying a slump value of 180~260 mm and a slump flow value not less than 400 mm was 0.95~1.106. However, the strength decreased with the increase in the water–binder ratio, conforming to a hyperbolic relationship. The all-solid waste fluidized filling material had strengths not less than 0.22, 1.09, and 1.95 MPa at 3, 7, and 28 d, respectively, meeting the workability requirements. Finally, a method for determining the optimal range of water–binder ratio considering both workability performance and strength is proposed based on the relationship between slump value, slump flow value, unconfined compressive strength, and the water–binder ratio.

Microstructure-mechanical property relationships of polymer nanocomposite reinforced with lyophilized montmorillonite/carbon nanotubes hybrid particles

Abstract Introducing multi-walled carbon nanotubes (MWCNT) and montmorillonite (MMT) simultaneously into a polymer can significantly enhance its properties. Meanwhile, choosing the best technique to homogeneously disperse these nanohybrid particles in polymers, without agglomerates, is still a challenge. In this study, a hybrid MMT/MWCNT, prepared by lyophilization process, is introduced in polylactide (PLA). Morphology of the resulting nanocomposites displays synergistic relationships of the MMT/MWCNT, facilitating dispersion in PLA. The analysis of transmission electron microscopy (TEM) specific particle densities of PLA0.5hyb, PLA1.0hyb, and PLA2.0hyb shows values of 77, 64, and 35 µm⁻2, respectively. This suggests that MMT platelets are significantly more exfoliated in PLA0.5hyb compared to the other nanocomposites. It also indicates that filler aggregation increases as the MMT/MWCNT concentration increases. Compared to neat PLA, elastic modulus of nanocomposites increased by up to 46 %, demonstrating the reinforcing effect of MMT/MWCNT hybrid nanofillers. The nanocomposites exhibit viscosity, plasticity and damage phenomena, which are significantly decreased because of the MMT/MWCNT incorporation, compared to neat PLA. Furthermore, the viscoelastic properties, analyzed by dynamic thermal-mechanical analysis, record about 27 % increase in the storage modulus of the nanocomposites compared to PLA, indicating the effectiveness of the hybrid MMT/MWCNT in increasing the resistance of PLA/MMT/MWCNT nanocomposite against thermomechanical aggression.

Fraction-dependent filler network in silicone rubber: Unraveling abrupt enhancement in rheological properties via solvent extraction and DLS study

A pivotal nanofiller network will be constructed by the filler loading threshold inside the silicone rubber, leading to abrupt enhancement in the rheological properties of the composites. However, the contribution of the nanofiller network to the performance mutation is poorly understood due to lack of direct evidence to recognize the formation of filler networks. This work quantitatively investigated the filler aggregation network of solvent-extracted monodisperse silica-filled polydimethylsiloxane (PDMS) composites to interpret the rheological properties. The results indicated that, when filler loadings reach 60 phr, the size of the filler network reaches its maximum (1280.5 nm), significantly increasing the storage modulus (166 kPa) and Payne effect (163 kPa), due to the formation of a filler network confirmed by Dynamic Light Scattering (DLS) and scanning electron microscope (SEM) observation. The reduction in aggregate size observed with longer extraction times is because of the collapse of the nanofiller network, which occurs as the polymer chains are removed. The aggregates reappear in a monodisperse form as the extraction duration reaches 20 days. This confirms that filler aggregates of interconnected polymer chains can form a well-developed network structure that effectively supports and transfers stresses. This contributes to an in-depth understanding of the formation mechanism of nanofiller networks, aiding the advancement of high-performance polymer nanocomposites.

Preparation of mixed matrix membranes with PVP-induced fluorinated Zr-MOF for high-efficiency hydrogen purification under high humidity conditions

Given that hydrogen production often involves impurities such as CO2, CH4, H2O, and alkanes, hydrogen purification is crucial for global green energy applications. Mixed matrix membranes (MMMs) using metal-organic framework (MOF) materials offer a non-thermal, energy-efficient method for hydrogen purification. These membranes have controllable structures and promote environmental sustainability. However, challenges such as filler aggregation and matrix-filler incompatibility during the preparation of MOF-MMMs are difficult to avoid and can adversely affect separation performance. In this study, 4-(trifluoromethyl) benzoic acid (4-TFMBA) was introduced in situ to grow synchronously with polyvinyl pyrrolidone (PVP) on UiO-66-NH2, forming a hydrophobic bifunctional nanoparticle composite, PVP-Zr-MOF-F. Furthermore, in situ loading of PVP-Zr-MOF-F onto a PVDF polymer matrix was achieved using a wet method and the NIPS technique to prepare PVP-Zr-MOF-F@PVDF. The introduction of 4-TFMBA, with highly electronegative F atoms, enhances hydrophobicity and increases H2 affinity through polarization and hydrogen bonding induced by C–F bonds. PVP promotes the formation of smaller Zr-MOF particles, increases the proportion of small pores, prevents aggregation, and acts as a pore-forming agent, facilitating the in situ loading and dispersion of PVP-Zr-MOF-F within PVDF chains. This bifunctionalization not only improves the compatibility and dispersion of the nanofillers but also increases the number of small pores, enhancing van der Waals forces and confinement effects on H2 molecules, making it suitable for gas separation under humid conditions. The results indicate that the H2 permeance of PVP2–Zr-MOF-F@PVDF can reach 114,735 GPU, with selectivities of 19, 21, 24, and 120 for H2/CO2, H2/CH4, H2/C2H4, and H2/n-C6H14, respectively, surpassing the 2008 Robeson's upper bound. Notably, under high humidity conditions, the selectivities for H2/CO2, H2/CH4, and H2/n-C6H14 are 1566 %, 1891 %, and 3264 % higher than those of the original PVDF membrane, achieving high selectivity separation. Additionally, after repetitive experiments with varying humidity, the membrane's selectivity remained almost unchanged, demonstrating the high hydrothermal stability of PVP2–Zr-MOF-F@PVDF. This research provides a new reference for hydrogen purification and holds significant implications for the sustainable development of green energy.

High-value application of kaolin by wet mixing method in low heat generation and high wear-resistant natural rubber composites

In this study, a silane coupling agent and kaolin, a natural mineral resource, were introduced into the wet mixing process of natural rubber latex, the high wear-resistant and low-generation heat natural rubber composites were prepared. The sputtering, collision, and deposition of coupling agent/fillers/natural rubber latex mixed emulsion onto the roller effectively could break up the filler aggregates, enable fillers to be better infiltrated, distributed, and dispersed in the rubber. The effects of dry/wet mixing processes and the ratio of kaolin to silica on the crosslinking density, filler dispersion, extrusion rheological properties, gas barrier properties, dynamic mechanical properties and thermal stability of NR composites were investigated, and the silanization mechanism was summarized by FTIR and XRD. The experimental results showed that kaolin improved the crosslinking density and failure temperature, reduced the Payne effect, extrusion swell, and rolling resistance. Compared with 60 phr silica-filled natural rubber, the gas barrier property and wear resistance of 60 phr kaolin-filled natural rubber were improved by 64 % and 27 %, respectively, and the rolling resistance was reduced by 57 %. When the ratios of silica to kaolin were both 20:40, the crosslinking density, gas barrier property, and wear resistance of wet mixing were improved by 24 %, 45 %, and 9 %, respectively, compared with dry mixing. This study provided a new method for the high-value application of kaolin in wet mixing and green tires.

Utilization of Buton Granular Asphalt (BGA) as Asphalt and Filler Content Substitution Material – in Asphalt Concrete Mixture- Wearing Course

Roads are one of the infrastructure that is urgently needed in improving the accessibility of an area and has a crucial role as a connecting infrastructure that facilitates the transportation of people and goods. This road must be able to handle the volume of traffic according to the plan, so planning must ensure smooth transportation. Asbuton can be used as a binding material on road pavements. However, the use of buton asphalt as a road construction material in Indonesia has not had a significant impact on infrastructure development carried out by the government. The purpose of this study is to analyze the characteristics of Marshall’s test value using Buton Granural Asphalt as a substitute for filler and Fine Aggregate in the mixture of Asphalt Concrete – Wearing Course (AC – WC). The type of data used is primary data obtained from laboratory test results and secondary data obtained from SNI Bina Marga 2018 rev.2. The results showed that with the addition of 19% BGA (Buton Granular Asphalt) as a filler and fine aggregate material, the stability of the mixture could be increased up to 2369,8 kg with the addition of BGA, when compared to aggregate without BGA, the stability value was higher. Based on the test of the characteristics of the 0% BGA mixture marshall obtained a density value of 2,304 t/m³, stability of 1240,6 kg, fatigue of 3.4 mm, Marshall Quotient (MQ) of 366,0 kg/mm, VMA of 16,3%, VFB of 76.2%, VIM of 3.9%. Marshall testing on a mixture of 19% BGA obtained a density value of 2325,0 t/m³, Stability of 2369,8 kg, Fatigue of 3.4 mm, Marshall Quotient(MQ) of 697,1 kg/mm, VMA of 15,4%, VFB of 80,0%, VIM of 3.1%. All test parameters meet the standards set out in the 2018 General Bina Marga specification for revision 2 road and bridge construction work, so that AC-WC asphalt concrete with 0% and 19% BGA substitution can be used.

A covalently integrated ZIF-8/polyamide acid mixed matrix membrane with superior gas separation performance

Zeolitic imidazolate framework-8 (ZIF-8) is a typical filler used to fabricate mixed matrix membranes (MMMs) on account of its attractive advantage of high selective permeability for gas separation. However, the performance is usually affected by filler aggregation due to strong interactions among fillers and weak interactions between the polymer and fillers, However, the performance is usually affected by filler aggregation due to strong interactions among fillers and weak interactions between the polymer and fillers, which will lead to a decrease of selectivity and the performance of gas separation will be strongly influenced. Herein, we modified ZIF-8 with 3-amino-1,2,4-triazole to obtain ZIF-8-NH2, Kapton polyamide acid was selected as the polymer matrix. Results showed that the ZIF-8-NH2/Kapton MMMs has a good compatibility interface between ZIF-8 and Kapton because of the covalent bridging, even the filler loading up to 45% (mass). The 45% (mass) of ZIF-8-NH2/Kapton membrane showed 297 Barrer (1 Barrer = 10−10 cm3 cm·cm−2·s–1·cmHg–1, 1 cmHg = 1333.22 Pa, standard temperature and pressure) of the permeability of H2 and 43.9 and 62.2 of selectivities for H2/N2 and for H2/CH4, respectively, which are beyond the upper limit of Robeson 2008.

Properties of EPDM Nanocomposites Reinforced with Modified Montmorillonite.

Considering the dilemma of obtaining economic and high-performance composites based on non-polar and main-chain-saturated ethylene propylene diene monomer rubber (EPDM), we proposed an effective and universal filler modification and nanocomposite preparation method. Specifically, the montmorillonite (MMT) surface was coated with polydopamine (PDA) to obtain DMMT, which was confirmed by XRD, XPS, FTIR, and TGA. After compounding DMMT gel with the solid EPDM via the gel compounding method, a silane coupling agent, vinyltrimethoxysilane, was introduced to construct covalent interactions between rubber and filler. Compared with the unmodified MMT filler EPDM, the EPDM/DMMT nanocomposite showed much fewer filler aggregates in the matrix. The highest tensile strength of the composites reached 6.5 MPa with 10 phr DMMT, almost 200% higher than that of pure EPDM.

Modulation of Mechanical Properties of Silica-Filled Silicone Rubber by Cross-Linked Network Structure.

Associating molecular structure and mechanical properties is important for silicone rubber design. Although silicone rubbers are widely used due to their odourless, non-toxic, and high- and low-temperature resistance advantages, their application and development are still limited by their poor mechanical properties. The mechanical properties of silicone rubbers can be regulated by designing the cross-link density and cross-linking structure, and altering the molar contents of vinyl in the side groups of methyl vinyl silicone rubber (MVQ) leads to different cross-linking structures and cross-linking densities in the vulcanized rubber. Therefore, this study investigated the differences in molecular parameters and molecular chain structures of unprocessed MVQ rubbers with different vinyl contents. The results showed that MVQ rubbers with high vinyl contents were branched polymers, better facilitating the cross-linking reaction than MVQ rubbers with low vinyl contents. In addition, silicone rubbers with different vinyl contents were co-cross-linked to introduce an inhomogeneous cross-linked network in the silicone rubber to improve its mechanical properties. The cross-linked network properties were analysed by the Flory-Rehner model and Mooney-Rivlin plots, and it was found that the long chains in the sparsely cross-linked domains of the network favoured high elongation at break and the short chains in the densely cross-linked domains contributed to high modulus, which could satisfy the functions of reinforcing and toughening the rubber materials at the same time. It was also found by analysing the filler network and aggregate morphology that the inhomogeneous cross-linked network led to an improvement in the dispersion of silica in the rubber and a significant improvement in the mechanical properties of silicone rubber.

A High-Quality Mixed Matrix Membrane with Nanosheets Assembled and Uniformly Dispersed Fillers for Ethanol Recovery.

A high-quality filler within mixed matrix membranes, coupled with uniform dispersity, endows a high-efficiency transfer pathway for the significant improvement on separation performance. In this work, a zeolite-typed MCM-22 filler is reported that is doped into polydimethylsiloxane (PDMS) matrix by ultrafast photo-curing technique. The unique structure of nanosheets assembly layer by layer endows the continuous transfer channels towards penetrate molecules because of the inter-connective nanosheets within PDMS matrix. Furthermore, an ultrafast freezing effect produced by fast photo-curing is used to overcome the key issue, namely filler aggregation, and further eliminates defects. When pervaporative separating a 5 wt% ethanol aqueous solution, the resulting MCM-22/PDMS membrane exhibits an excellent membrane flux of 1486g m-2 h-1 with an ethanol separation factor of 10.2. Considering a biobased route for ethanol production, the gas stripping and vapor permeation through this membrane also shows a great enrichment performance, and the concentrated ethanol is up to 65.6 wt%. Overall, this MCM-22/PDMS membrane shows a high separation ability for ethanol benefited from a unique structure deign of fillers and ultrafast curing speed of PDMS, and has a great potential for bioethanol separation from cellulosic ethanol fermentation.

Multi-Factor Orthogonal Experiments and Enhancement Mechanisms of Unconfined Compressive Strength of Soda Residue Cement Lime Soil

In order to study the effects of soda residue content, particle size, moisture content, and curing age on the unconfined compressive strength (UCS) of soda residue cement lime soil (SRCLS), a 4-factor, 4-level orthogonal experimental design was employed in this study. Different conditions of SRCLS UCS and their impacts were tested and analyzed. The internal microstructure and hydration products of SRCLS were studied using SEM and XRD to explore the strengthening mechanism of SR in SRCLS. The results indicate that as the soda residue content gradually increased, SRCLS UCS initially increased and then decreased, with a maximum increase of up to 67%. With increasing soda residue particle size and moisture content, the UCS of SRCLS gradually decreased. The optimized mix ratio was determined to be soda residue:cement:lime:soil = 3%:3%:6%:100%, with the soda residue dried naturally and an ideal particle size of 0.15 mm. The factors influencing the unconfined compressive strength (UCS) of SRCLS, in order of importance, are curing age, soda residue content, moisture content, and particle size of SR. Among these, curing age and soda residue content have a significant impact on the UCS. An adequate amount of SR can act as a fine aggregate filler, replace lime, promote cement hydration, and enhance chloride ion binding. This improves the grading of SRCLS materials and facilitates the formation of cementitious products from AFm, AFt, and Friedel’s salt, resulting in denser and stronger SRCLS materials. The research findings provide a reference for the mix design of SRCLS and the large-scale utilization of waste soda residue.

Deterioration micro-mechanism of graded aggregates with different gradations under vibratory compaction using X-CT testing

This study aims to explore the compaction deterioration micro-mechanism of high-speed railway graded aggregate (HRGA) fillers and further improve the compaction quality of HRGA fillers, contributing to improving subgrade service performance. Firstly, based on the vibratory compaction experiments, the compaction deterioration macro-characteristics of HRGA fillers with different gradations were revealed from the mechanical properties (i.e., dynamic stiffness Kd and subgrade reaction modulus K20). Secondly, X-ray Computed Tomography (X-CT) testing was conducted based on the multiple typical compaction stages selected from the Kd curve. The internal microstructure (i.e., particles and voids) characteristics within HRGA fillers with different gradations were measured by high-precision image processing approaches. Finally, the evolution characteristics of Kd, K20, and microstructure were used to reveal the compaction deterioration micro-mechanism of HRGA fillers with different gradations, and further explore the relationship between filler gradation and compaction deterioration. The results indicated that compaction deterioration characteristics of HRGA fillers with different gradations could be characterized by the inflection points of Kd and K20 curves. Besides, during compaction deterioration, particle abrasion crushing and the increase in surface edges and corners of the void reduced the stability of the skeleton structure within HRGA fillers with different gradations, resulting in a gradual decrease of Kd and K20. Furthermore, the relationship between Kd, K20, and microstructure with gradation could be quantitatively characterized by quadratic functions. Hence, based on X-CT measurement, it was feasible to reveal the compaction deterioration mechanism of HRGA fillers from macro- and micro-perspectives. This study contributes to establishing a theoretical framework for revealing the compaction deterioration of high-speed railway subgrade fillers and improving the quality of vibratory compaction for on-site subgrade construction.

Characterization of Asphalt Filler Mastics with Industrial By-Products as Fillers under the Coupled Effect of Aging and Moisture

An asphalt mix comprises asphalt binder and aggregates of different sizes (coarse and fine) and filler. Even with a smaller share, filler plays a crucial role in the performance of asphalt-filler mastics. The study is motivated by the growing need to preserve natural resources and aims to investigate the utilization of four different industrial by-products/wastes (electric arc furnace slag filler, basic oxygen furnace slag filler, tire pyrolysis char filler, and plastic pyrolysis char filler, and one conventional natural stone aggregate filler (NSAF) in asphalt-filler mastics. Four conditioning environments were used to characterize the chemo-rheological properties of the mastics formulated by these five different fillers: unaged, long-term aged, freeze-thaw, and freeze-thaw of long-term aged mastics. To understand the significance of filler attributes in the filler-asphalt mastic performance, a correlation between various filler characteristics (specific surface area, Rigden voids, methylene blue value, and hydrophilic coefficient) and the mastic properties (multiple stress creep and recovery, linear amplitude sweep, binder yield energy test, and Fourier transform infrared spectroscopy) was also attempted. The fatigue life and elastic recovery of the mastics were negatively affected by the combined effects of aging and moisture. The filler characteristics showed a negligible-to-low association with fatigue parameters and a good correlation with rutting performance. The use of these industry co-products/by-products as fillers is supported by the superior rutting and fatigue performance of steel slag and pyrolytic char fillers compared with the traditional NSAF.

Algorithms to create realistic virtual asphalt mixtures

This paper presents a set of algorithms for creating realistic three-dimensional (3D) models of asphalt mixtures based on its composition. The process begins by measuring the shape of the aggregates in the asphalt mixture. Using these measurements, an algorithm creates 3D volumes that approximate the size and shape of the aggregates. These volumes are then added to a virtual mixer in the same proportions as the aggregates in the real mixture and are pressed together until the air void content of the 3D model matches that of the real asphalt. This results in realistic models of aggregate skeletons in the asphalt mixture. Next, sections are taken from the aggregate skeletons and a mortar mixture, made up of bitumen, filler and fine aggregates, is applied to the sections. Geometrical rules are used to determine which areas of the sections are covered in mortar and which are air voids. The validation of virtual aggregates and air voids has demonstrated good correlations with actual ones. The resulting models are highly realistic and can be used to predict the mechanical or physical properties of asphalt mixtures in future studies.

A Comparative Evaluation of The Mechanical Properties of PET and Polystyrene Modified Asphaltic Concrete Containing Rice Husk Ash Filler.

The study evaluated and compared the influence of bitumen modification for sustainable as- phalt using waste plastic (Polyethylene Terephthalate, PET) and waste Polystyrene (PS) at 5–50% modification levels. Rice husk ash (RHA) and desilted sand were used as filler and fine aggregate with crushed granite as coarse aggregate. Tests conducted include; penetration, viscosity, flash point, fire point, specific gravity, ductility and marshal stability test on asphalt. For PET modi- fied-binder a decrease in penetration and ductility was observed while the specific gravity, vis- cosity, flash and fire points of the binder increased. For the PS modified-binder, the penetration, ductility, viscosity and specific gravity decreased with an increase in PS while the flash and fire point increased. Marshall Stability results showed an optimal of 20% PET modification was ade- quate for medium traffic surfaing with stability, flow, density, air void, void in mineral aggregates (VMA), and Void filled with binder (VFB) of 4875N, 3.53 mm, 2.460 g/cm3, 3.30%, 18.20%, and 81.87% respectively. For 10% PS modification content, the stability, flow, density, air void, void in mineral aggregates (VMA), and Void filled with binder (VFB) were found to be 6825N, 3.33 mm, 2.362 g/cm3, 4.52%, 18.21%, and 75.18% respectively which was found to be adequate for heavy traffic surfacing. Hence, it was concluded that the investigated waste plastics could be used in Asphalt pavement courses. If applied, these results could provide low-cost materials for paving roads while also reducing waste-related pollution and environmental issues.

Bio-Composite Filaments Based on Poly(Lactic Acid) and Cocoa Bean Shell Waste for Fused Filament Fabrication (FFF): Production, Characterization and 3D Printing.

In this study, novel biocomposite filaments incorporating cocoa bean shell waste (CBSW) and poly(lactic acid) (PLA) were formulated for application in Fused Filament Fabrication (FFF) technology. CBSW, obtained from discarded chocolate processing remnants, was blended with PLA at concentrations of 5 and 10 wt.% to address the challenge of waste material disposal while offering eco-friendly composite biofilaments for FFF, thereby promoting resource conservation and supporting circular economy initiatives. A comprehensive analysis encompassing structural, morphological, thermal, and mechanical assessments of both raw materials and resultant products (filaments and 3D printed bars) was conducted. The findings reveal the presence of filler aggregates only in high concentrations of CBSW. However, no significant morphological or thermal changes were observed at either CBSW concentration (5 wt.% and 10 wt.%) and satisfactory printability was achieved. In addition, tensile tests on the 3D printed objects showed improved stiffness and load resistance in these samples at the highest CBSW concentrations. In addition, to demonstrate their practical application, several 3D prototypes (chocolate-shaped objects) were printed for presentation in the company's shop window as a chocolate alternative; while retaining the sensory properties of the original cocoa, the mechanical properties were improved compared to the base raw material. Future research will focus on evaluating indicators relevant to the preservation of the biocomposite's sensory properties and longevity.

Near‐infrared light response novel shape memory actuator based on photothermal rGO‐TiO2 filler

AbstractAs an efficient method to realize photoinduced shape memory, photothermal filler has the characteristics of economy and convenience. However, the aggregation of the photothermal filler in the matrix material will reduce the material's shape memory and mechanical properties. In this work, the photothermal filler of reduced graphene oxide (rGO)‐titanium dioxide (TiO2) was prepared by the solvothermal method and then introduced into the polycaprolactone (PCL) matrices to construct a photoresponsive actuator. Because of TiO2 is uniformly loaded on the rGO surface, rGO‐TiO2 disperses well in the composites. When the GO:TiO2 ratio of photothermal filler is 1:1, the mechanical properties of PCL‐GT‐3 are the best, and the tensile strength and elongation at break are 31.8 MPa and 239.5%, respectively, and the crosslinking material under near‐infrared light has a good photothermal effect. Due to the induced difference between the in‐plane stress of the surface and the volume layer, the shape transformation can be controlled by very low energy (808 nm, 700 mW near‐infrared laser). The scheme of controlling the properties of the photoinduced shape memory material by changing only the filler type is conducive to commercial application.

Nano‐BN/Nano‐TiO2 and micro Mg(OH)2 loaded hybrid ethylene propylene diene monomer elastomer composites for outdoor high‐voltage insulation application

AbstractThis work deals with the synthesis, characterization of hybrid ethylene propylene diene monomer (EPDM) composites loaded with nano‐boron nitride (nano‐BN)/nano‐titanium dioxide (nano‐TiO2) and micro Mg(OH)2 particles for its suitability towards high‐voltage insulation application. The elastomer samples were prepared by carefully dispersing the micro and nano fillers during the mastication process of EPDM polymer using a two roll mill, followed by vulcanization. The samples were characterized for mechanical, morphological, thermal, and electrical insulation properties. The highest tensile strength among the composite samples was noted for 1 phr nanoparticles loaded samples. Fourier Transform Infrared (FTIR) results show no change in the chemical moiety upon addition of nano‐BN/nano‐TiO2 in EPDM composites. Enhancement in hydrophobicity is observed for 3 phr nano‐TiO2 loaded composites, which shows a maximum static contact angle of 110°. Meanwhile remarkable enhancement in the thermal conductivity and volume resistance of the composites are contributed to the addition of nano‐BN, thereby achieving maximum dielectric breakdown voltage (i.e., ~21 kV/mm for EMB3). Scanning electron microscope images and atomic force microscopy (AFM) topography highlight that low concentration (i.e., 1 phr) based composites have homogeneous dispersion in matrix and excessive nano filler addition deteriorates properties by forming filler aggregates and increasing surface roughness.

Investigating the Influence of Rigden Void of Fillers on the Moisture Damage of Asphalt Mixtures

Moisture damage and bond loss are major factors in pavement degradation, often stemming from excessive moisture accumulation due to weather events. Water infiltrates the gap between asphalt binder and aggregate, weakening the asphalt bond. Rigden Void (RV) has emerged as a crucial parameter in assessing the susceptibility of asphalt mastic-aggregate systems to moisture-induced damage. However, numerous waste natural fillers have been researched as potential aggregate filler replacements, yet their role in moisture damage remains unexplored. Therefore, this study aimed to understand how different fillers, including waste natural materials like coconut peat and bagasse, affect asphalt mixture performance and moisture damage. Results showed that Rigden Voids were positively correlated with pore size and negatively correlated with surface area. Larger pores contributed to higher Rigden Voids, while greater surface areas led to lower values. Limestone had the highest Rigden Void percentage due to its larger pore size and lower surface area. The research also explored contact parameters between fillers and asphalt, revealing varying interactions based on filler and asphalt types. Moisture damage testing demonstrated that all mixtures, both dense and porous, displayed good resistance to moisture damage. The correlation analysis between Rigden Voids and moisture damage revealed varying degrees of influence, dependent on asphalt type and aggregate gradation. Doi: 10.28991/CEJ-2023-09-12-014 Full Text: PDF