Hybrid Fillers Research Articles

Effects on microhardness, tensile strength, deflection, and drop weight impact resistance with the addition of hybrid filler materials for enhancing GFRP composites.

The work evaluated the usage of various filler materials, namely aluminium oxide (Al2O3), magnesium (Mg), and glass powder, in the bidirectional glass fibre reinforced polymer (GFRP) composites. The required samples were fabricated using the hand lay-up technique by varying the filler material proportions from 0%wt. to 7.5%wt., including individual and hybrid mixture combinations. The prepared samples were evaluated for their microhardness, tensile strength, deflection characteristics, and drop-weight impact resistance. It was observed that the optimal addition of individual filler material improved the microhardness and tensile strength more than that of neat composites. In contrast, hybrid compositions at higher proportions exhibited brittleness and lower enactment due to their poor interfacial bonding and particle agglomerations. The deflection characteristics and drop-weight impact tests also showed enhanced stiffness and impact resistance with the addition of hybrid mixtures of filler materials to the composites. The study supports the potential use of adding filler materials to the composites for lightweight structural applications.

Clinical Outcomes and Safety Profile of a Dextranomer-Hyaluronic Acid Hybrid Filler: A Case Series Analysis.

The demand for aesthetic treatments targeting the middle and lower face is on the rise, especially because of changes in appearance associated with aging. This study aimed to assess the use of a hybrid filler for sculpting and contouring of the chin, jaw, and malar region. A retrospective analysis was performed on patients who underwent jaw and chin contouring and cheek augmentation using a hybrid filler (hyaluronic acid and dextranomer). The evaluation focused on the naturalness of appearance, enhancement in volume, and the durability of the results, employing a 5-point scale. Both patient satisfaction and physician evaluations were measured using the Likert scale and the Global Aesthetic Improvement Scale (GAIS), respectively. Follow-up with patients extended up to 6 months after treatment, during which any treatment-related adverse events (AEs) were meticulously recorded and analyzed. Nineteen patients participated in the study, receiving an average injection volume of 2.4 ± 0.9 mL to attain the desired outcomes. The evaluation of natural appearance, volumizing effects, and durability at the analyzed time point consistently scored above 4. All 19 patients' aesthetic improvement was evaluated as "very much improved" and "much improved", at the GAIS score. All patients report improvement in their appearance, with 89.5% rating it as "very much improved" or "much improved" on the Likert scale. Only expected AEs such as mild pain and lower swelling were registered. The hybrid filler proved effective and safe for facial contouring, with significant patient satisfaction and minimal adverse effects.

The Low-Temperature Thermal Conductivity of Epoxy Resin Composites Enhanced by Graphene and Modified Alumina Hybrid Fillers

In recent years, polymer/ceramic composites with high thermal conductivity have been widely used in microelectronic devices, superconducting magnets and aviation, and further improving their thermal conductivity is a great challenge. In this work, spherical alumina nanoparticles were modified with 3-aminopropyltriethoxy-silane (APTES) successfully. Furthermore, the modified Al2O3(M-Al2O3)/Epoxy(EP) and Graphene(Gr)/M-Al2O3/EP composites were prepared and their properties were tested in the temperature range of 70 K-300 K. The results showed that the thermal conductivity of the composite with 1 wt% Gr and 60 wt% M-Al2O3 hybrid filler is 15 times higher than that of pure epoxy at 70 K, which indicates its application prospect in thermal interface materials.

Construction of multi-functional silicone rubber/reduced graphene oxide/multi-walled carbon nanotube composites with segregated structure by surfactant-free Pickering emulsion method

Polymer composites with segregated structure (PC–S) have the advantages of low filler usage and excellent functionality. Emulsion blending combined with direct molding technology is the main method for the preparation of PC-S. However, due to the high fluidity of low-viscosity silicone rubber (SR), PC-S cannot be prepared by this technique. In addition, surfactants affect the heat resistance of the final SR composites (SRC). In order to solve the above problems, in this study, a Pickering emulsification combined with pre-crosslinking technology for SR was successfully developed by using graphene oxides (GO)/multi-walled carbon nanotubes (MWCNTs) hybrid fillers (GM) as emulsifiers, and SR/reduced GO (RGO)/MWCNTs composites with segregated structure (SSGM) were prepared. When RGO content is 4.5 wt%, MWCNTs content is 3.2 wt%, SSGM shows the highest electrical conductivity of 12.5 S/m, the highest electromagnetic interference shielding efficiency (EMI SE) of 41.4 dB, and an excellent flame retardant performance. The whole preparation process avoids the use of organic solvents and surfactants, which reduces the production cost of SSGM and the environmental pollution, and provides a feasible preparation route for the industrialized production of SSGM.

Improved mechanical, thermal, and barrier properties of halloysite nanotubes and nanocellulose incorporated PVA-PEO films: For food packaging applications

This work presents a novel polyvinyl alcohol (PVA)-polyethylene oxide (PEO) nanocomposite with halloysite nanotube (HNT)-nanocellulose (NC) hybrid filler to tailor the mechanical, thermal, and barrier properties. PVA-PEO/ HNT-NC nanocomposites are characterized using various analytical techniques such as FTIR, XRD, TGA, DSC, and SEM. The study evaluated the impact of hybrid filler on water vapor transmission rate (WVTR), moisture retention capacity (MRC), peroxide value (POV), and mechanical properties. The simultaneous application of 3 wt% HNT and 5 wt% NC resulted in a 20 % increase in tensile strength and approximately two-fold increase in Young's modulus, with a maximum degradation temperature increase of 22° C and 16° C in the second and third stages, respectively. Compared to the pure blend, the nanocomposite exhibited a 67 % (26.7 ± 0.6 mEq/kg) improvement in oxygen barrier performance, while maintaining a low WVTR and good MRC, demonstrating their suitability for packaging applications.

Tailoring the properties for composites based on xGNP, TiC and nursing their biocompatibility for wearable technologies

Recently, the balance of stiffness, response time, output voltage, and nursing their biocompatibility are hot research topics and thus developed in the present work. Here, the configurations show the importance of harvesting mechanical energy into electric energy through the piezoelectric mechanism. Some basic strategies to achieve this work's goal involve using stretchable and dielectric elastomers such as silicone rubber (SR) as host matrix to fabricate the device. Then, the addition of 2-dimensional reinforcing and electrically conductive fillers such as exfoliated graphene nanoplatelets (xGNPs) or Titanium carbide (TiC) into the SR matrix was fabricated. Results show that at 5 phr of xGNP-filled composites, the compressive load was ∼275 N for 1 sample, ∼550 N for 2 replicas, and ∼ 650 N for 3 replicas. Similarly, the stretchability was 92 % (unfilled), and at 5 phr, it was 114 % (xGNP), 154 % (TiC), and 106 % (hybrid filler). For an electrode area of 235.5 mm2 (3 replicas), the output voltage was ∼1.6 mV (xGNP), ∼0.95 mV (TiC), and ∼ 0.45 mV (Hybrid). Similarly, for an electrode area of 235.5 mm2 (3 replicas), the response time was ∼283 ms (xGNP), ∼297 ms (TiC), and ∼ 307 ms (Hybrid). The durability tests were also performed and the results show that the voltage drop was negligible from initial to final cycles. Finally, the biocompatible tests were performed. The results show that the samples tested in the present work are biocompatible and can be useful for wearables or as implants for biomedical applications.

Thermally conductive, mechanically robust alumina-incorporated polyurethane films prepared by ultraviolet light curing

Abstract The development of heat dissipating composite materials for electronic systems can be expedited using alumina particles as modifiable polymer-matrix fillers. However, these composites are difficult to synthesize given the tradeoffs between thermal conductivity, insulating characteristics, and conduciveness to processing. To that end, the present study is focused on synthesizing environmentally friendly polyurethane films that could be cured by ultraviolet light within minutes, without requiring high-temperature heat treatment. Through the optimization of alumina modification, hybridization of thermally conductive fillers, filler content, and stirring time on the thermal conductivity of the polyurethane composites, this study improves the process for sustainability, low-cost, and convenient preparation. The experimental results confirmed that the use of surface modification and hybrid fillers is effective for enhancing the thermal conductivity, with the value of the polyurethane integrated with 50 wt% Al2O3 and 5 wt% Al2O3–poly (catechol/polyamine) being 76.40 wt% higher than that of pure PU (0.44 W/mK). Additionally, the use of hybrid fillers resulted in superior mechanical and thermal properties (such as tensile strain, tensile strength, thermal expansion coefficient, and temperature resistance) compared with those of pure PU and films incorporated with only a single filler.

Diffusion Behavior of Organic Solvents in Graphene Oxide/Nano Silica Hybrid Natural Rubber Latex Nanocomposite: Experimental and Theoretical Approach

AbstractThis study explores the impact of a graphene oxide (GO)/nano silica (NS) hybrid (GO/NS) filler on the diffusion characteristics of natural rubber (NR) composites when exposed to toluene, xylene, and hexane solvents. The lowest solvent uptake is observed for NR GO/NS 3 (3 phr), which is attributed to forming a robust filler network within the composite. The calculation of crosslink density using the Flory‐Rehner equation reveals significantly higher values for NR GO/NS 3, indicating good crosslinking density in the presence of the hybrid filler. Furthermore, molecular mass between crosslinks (Mc) is calculated, demonstrating a favorable fit with the Affine model. The investigation extends to theoretical modeling, where the Korsemeyer–Peppas and Peppas–Sahlin models are employed to predict solvent uptake behavior. Strikingly, the experimental values exhibit a strong alignment with the Peppas–Sahlin model. This comprehensive analysis provides valuable insights into the diffusion behavior of graphene oxide/nano silica (GO/NS) hybrid‐reinforced natural rubber latex in organic solvents, highlighting potential applications in areas such as solvent‐resistant coatings, barrier materials for chemical storage, and enhanced performance in protective gloves and seals used in harsh chemical environments.

Nanocellulose‐polypropylene composites with novel antimicrobial complex salt

AbstractPolypropylene composites with different contents of zinc‐ammonium salts (3, 5 and 7 wt%) and nanocellulose (1 wt%) after enzymatic bioconversion were characterized by structural, dispersion‐morphological, thermal, antimicrobial and mechanical analysis. It was shown that the use of a newly synthesized salt significantly affected the formation of the supermolecular structure of the polymer matrix and increased the nucleation activity, thermostability and flexibility of the composite materials. Moreover, the addition of the inorganic filler allowed to obtain composites with very good antimicrobial properties against Staphylococcus aureus, Escherichia coli and Candida albicans. An interesting relationship between the degree of filler dispersion in the polymer matrix and the formation of polymorphic varieties was elucidated in the study, which contributes to the improvement of final performance characteristics of composite materials. It is noteworthy that a hybrid filler in the form of nanometric cellulose and a biocidal additive containing zinc‐ammonium complex salt was used for the first time. Research has shown that such polymer composites can find application during the manufacture of smart packaging materials with enhanced barrier properties against oxygen and water vapor as well as improved biocidal characteristics, which will notably extend food storage time. At the same time, the presented process of obtaining the innovative composite materials is an excellent example of sustainable technologies for the design of antimicrobial treatments, while guaranteeing the possibility of further processing of these composite materials through material recycling.Highlights Zinc‐ammonium complex with antimicrobial properties was obtained The strength properties and thermal stability of the composites were improved Degree of filler dispersion in polymer affects formation of polymorphic varieties The composites can be applied in the production of smart packaging materials

Structural Design of Hybrid Fillers in a Polymer Matrix for Advanced Electromagnetic Interference Shielding

The rapid development of modern advanced electronic systems has created a pressing need for multifunctional polymer composites that can withstand external adversities such as electromagnetic waves, flames, and mechanical stresses. Although these requirements can be satisfied by incorporating different types of fillers, high filler loadings often lead to issues such as poor processability and increased material costs. Herein, a multifunctional polyamide‐6 composite is introduced using a carbon‐fiber flame‐retardant hybrid filler to design a next‐generation electromagnetic interference (EMI) shielding system. Based on the synergistic effect of the functionality and structural arrangement of these fillers in the composite, the EMI shielding system demonstrates high EMI shielding performance, improved mechanical properties, and excellent flame retardancy despite the low filler content. The scalability and multifunctionality of the proposed system highlight its potential for use in next‐generation applications, such as electric vehicles, aerospace, and 5G/6G telecommunications.

HArmonyCa™ hybrid filler to restore connective tissue: An Italian real-life retrospective study.

Facial aging and dermal conditions may negatively influence the quality of life, leading patients to seek aesthetic procedures to restore a more satisfying appearance. HArmonyCa™ is a recently developed hybrid filler that combines the actions of the most common dermal fillers, hyaluronic acid (HA) and calcium hydroxylapatite (CaHA). This study investigates the efficacy and safety of HArmonyCa™ in patients affected by chrono- and photoaging and several facial skin conditions. One hundred and twenty-nine patients, affected by chrono- and photoaging, and skin conditions such as oily and acne-prone skin, rosacea, or scarring, were treated with HArmonyCa™. Injections followed the retrograde linear fanning technique. A physicians' consensus identified five optimal entry points. The physician and patients assessed treatment outcomes using the Global Aesthetic Improvement Scale (GAIS) 9 months after treatment (including immediate lift effect, skin firmness, and elasticity), and 3D images were taken for documentation. Adverse events (AEs) were evaluated immediately after the procedure and after 9 months. According to the physician's assessments, all patients displayed an improvement in facial appearance, particularly during movement, with the patients' evaluation showing agreement. Only minor AEs were reporte, which resolved spontaneously. Moreover, HArmonyCa™ treatment proved compatible with different medications and aesthetic procedures. This study shows that one treatment with HArmonyCa™ yields highly satisfactory outcomes in patients affected by skin conditions. For the first time, we show that HArmonyCa™ is a dynamic filler that improves facial laxity during movement. The treatment proved to be safe and fully compatible with other cosmetic procedures and medications.

Flexural strength and viscosity of dental luting composite reinforced with zirconia and alumina

Objectives Optimum flexural strength and viscosity are essential for longevity while efficiently handling dental luting composite. This study aims to investigate the effects of zirconia and alumina on the flexural strength (FS)and viscosity of dental cement made of silica rice husk. Materials and Methods Study groups with different percentages of weight (wt.): Group 1 (3 wt.% zirconia), Group 2 (3 wt.% alumina), and Group 3 (3 wt.% zirconia and 2 wt.% alumina), negative control specimen (0 wt.% zirconia/ alumina) and Rely-X U200 (3M ESPE). A universal testing machine and a rheometer were used to test FS and viscosity, respectively. One-way ANOVA and post-hoc Bonferonni test were used for data analyses. Results and Discussion FS and viscosity for Group 3 (3 wt.% zirconia and 2 wt.% alumina) were significantly higher compared to the negative control (p<0.05). Conclusion: Adding zirconia and alumina improved flexural strength without compromising the viscosity of dental luting composite. This experimental dental luting cement using hybrid fillers could be an alternative to resin luting cement. Bangladesh Journal of Medical Science Vol. 23 No. 04 October’24 Page : 1048-1053

Fabrication and comparison of interlaminar fracture toughness behaviour of glass epoxy composites with recycled milled Kevlar-carbon hybrid fillers

Current research uses a novel recycled milled carbon (rmCF), recycled milled Kevlar (rmKF), and innovative Hybrid fillers (rmHF) of both to increase glass/epoxy composite laminate delamination resistance. This study examines how crack propagation and fibre orientation affect laminated composite delamination fracture toughness. Recycled milled Fillers in the interlayer increase stiffness, delamination resistance, and fracture toughness by increasing the energy needed to crack the interlaminar domain. Here, Mode I, Mode II, and Mixed Mode (I/II) with GIGII = 25 %, 50 % and 75 % were studied for four different Interface fibre orientations. It appears [06/902/06] increased delamination toughness. Adding the novel recycled milled fillers improved delamination resistance. Among the three fillers, rmCF increased fracture toughness by 271 % and rmHF and rmKF composites had 220 % and 182 % higher fracture toughness. The synergy compensated for Kevlar's lower fracture toughness in the hybrid (rmHF). SEM analysis of fractured surfaces revealed crack deflection, individual debonding, and filler/matrix interlocking, all of which increase fracture toughness on different levels.

Effect of natural hybrid fillers reinforced vinyl ester composites on mechanical and physical properties

Effect of natural hybrid fillers reinforced vinyl ester composites on mechanical and physical properties

Environmentally Benign High‐Performance Composites‐Based Hybrid Microcrystalline Cellulose/Graphene Oxide

ABSTRACTA novel silane functionalization prepared by a solution mixing approach of epoxy composites filled with eco‐friendly reinforcement filler, that is, graphene oxide (GO) and microcrystalline cellulose (MCC). The developed composites were subjected to comprehensive analysis using various characterization techniques, encompassing mechanical testing, water absorption analysis, thermal stability assessment, and scanning electron microscopy (SEM). The tensile strength and Young's Modulus of the epoxy composite filled with 1.0 wt.% of GO (EGO1.0) demonstrated the highest value viz. 29.83 MPa and 1991.71 MPa, respectively, when compared to neat epoxy composite (E0). Meanwhile, the thermal gravimetry analysis (TGA) studies, particularly char yield, highlight improvements in the thermal stability of the EGO2.5 composite, that is, 23.39% representing a 33.73% increment compared to the E0 composite. The synergistic effect of hybrid filler, achieved by a combination of micro and nanoparticle fillers within an epoxy matrix, was investigated as a virtuous alternative to the conventional epoxy nanocomposites. A uniform dispersion of GO on the MCC surface leads to significant improvements in the mechanical properties and thermal stability of the epoxy‐reinforced composite. The maximum tensile strength, Young's Modulus, and break strain of 39.77 MPa, 2591.27 MPa, and 2.90%, respectively, were observed for the modified EGO1.0MCC1.5 composite. The synergistic effect of hybrid eco‐friendly reinforcement fillers (GO/MCC) and a strong interfacial adhesion between the matrix and filler reduces the formation of defects, thereby resulting in good stress transfer from matrix to fillers.

Hybrid Carbon Black/Silica Reinforcing System for High-Performance Green Tread Rubber.

Silica, as a high-quality reinforcing filler, can satisfy the requirements of high-performance green tread rubber with high wet-skid resistance, low rolling resistance, and low heat generation. However, the silica surface contains abundant silicon hydroxyl groups, resulting in a severe aggregation of silica particles in non-polar rubber matrix. Herein, we explored a carbon black (CB)/silica hybrid reinforcing strategy to prepare epoxidized natural rubber (ENR)-based vulcanizates. Benefiting from the reaction and interaction between the epoxy groups on ENR chains and the silicon hydroxyl groups on silica surfaces, the dispersion uniformity of silica in the ENR matrix was significantly enhanced. Meanwhile, the silica can facilitate the dispersity and reinforcing effect of CB particles in the ENR matrix. By optimizing the CB/silica blending ratios, we realized high-performance ENR vulcanizates with simultaneously improved mechanical strength, wear resistance, resilience, anti-aging, and damping properties, as well as reduced heat generation and rolling resistance. For example, compared with ENR vulcanizates with only CB fillers, those with CB/silica hybrid fillers showed ~10% increase in tensile strength, ~20% increase in elongation at break, and ~20% increase in tensile retention rate. These results indicated that the ENR compounds reinforced with CB/silica hybrid fillers are a promising candidate for high-performance green tread rubber materials.

Hybrid polymer composites of Terminalia chebula filler reinforced thermal and mechanical characterization of bagasse/tamarind seed

The development of manufacturing industries is crucial for national progress, with a growing emphasis on green and sustainable practices. This study investigates the development and performance of hybrid polymer composites based on poly lactic acid (PLA) reinforced with lignocellulosic fillers: bagasse fiber (BF), tamarind seed fiber (TSF), Terminalia chebula fiber (TCF), and a hybrid filler of bagasse, tamarind seed, and Terminalia chebula (BTSTCF). Five types of composites were fabricated with varying filler compositions: PLA, PLA/BF, PLA/TSF, PLA/TCF, and PLA/BTSTCF, consisting of 30% BF, TSF, or TCF with 70% PLA, and an additional 10% of each filler in the BTSTCF composite. The results demonstrated that the PLA/BTSTCF hybrid composite outperformed others regarding mechanical strength, thermal stability, and interfacial adhesion. Specifically, it exhibited superior flexural strength, impact strength, and tensile strength. The findings indicate that incorporating a combination of bagasse, tamarind seed, and Terminalia chebula fillers into PLA significantly enhances its properties and performance. This study contributes to advancing sustainable and green manufacturing practices and holds promise for economic growth through the development of high-performance, eco-friendly materials.

The Hybrid Filler Technique: A 5-Year Retrospective Analysis.

The combination of calcium hydroxylapatite (CaHA) and hyaluronic acid fillers (CPM-HA, cohesive polydensified matrix-based hyaluronic acid fillers, Belotero® range, Merz Pharmaceuticals GmbH, Frankfurt, Germany), known as hybrid fillers, has emerged as a popular approach in aesthetic medicine. Premixed CaHA with CPM-HA offers several advantages, including enhanced tissue elevation and reduced early volume loss after injection. The objective of the present study is to assess the safety of premixing CaHA and CPM-HA fillers for rejuvenation purposes or as an aesthetic harmonization treatment. This retrospective study presents the clinical experience of two expert injectors who consistently used premixed CaHA and CPM-HA fillers for aesthetic treatments between March 2018 and December 2023. The premixed hybrid formulation was standardized and administered following a published protocol. A total of 2112 patients were treated, with meticulous follow-up over a minimum of one year. In the 2112 patients treated, only 5 minor adverse events (0.24%) were reported. The adverse events consisted of 4 non-inflammatory nodules of which 2 completely resolved with hyaluronidase, and 1 case of transient edema. Secondary findings consist of the treated areas, type of CPM-HA used and mixing ratios that were applied. The results from the current retrospective study, with the largest published cohort so far, are consistent with prior publications and strongly support a good safety profile of the CaHA:CPM-HA hybrid blend. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Advanced carbon-silica hybrid fillers for enhanced rubber compounds in tires

Advanced carbon-silica hybrid fillers for enhanced rubber compounds in tires

Covalent and non‐covalent action‐enhanced cellulose‐based thermally conductive composite (TCC) films fabricated via vacuum‐assisted self assembly with high thermally conductivity and superior mechanical performance

AbstractAs is known, to establish covalent or non‐covalent interaction between filler and matrix, which helps to reduce the interface thermal resistance (ITR) as well as construct good thermal conduction channels, is a good strategy for dealing with the risk of thermal runaway in the extreme service environment of electronic equipment. In this paper, carboxylated nanocellulose fiber (c‐CNF) was used as matrix, and a hybrid filler (M‐CoNPs@GNP) was fabricated by coating cobalt‐nanoparticles (CoNPs) and grafting maleimide on graphene nanosheets (GNPs). M‐CoNPs@GNP/c‐CNF thermally conductive composite (TCC) films were successfully fabricated by combining with c‐CNF. As zero‐dimensional particles, CoNPs can effectively prevent GNPs agglomeration due to surface effects, and “‐NH” in maleimide dehydrates with “‐COOH” in c‐CNF to form “C‐N‐C” covalent bonds, with strong hydrogen bond formed between filler and matrix, which remarkably enhances the interface compatibility between matrix and filler. The ITR has been reduced to form a well‐defined three‐dimensional thermal conduction path, achieving an ultra‐high in‐plane TC (35.9 W·m−1·K−1) for MCGC40, which is 7.9 times that of pure c‐CNF film, in addition to a sufficiently high tensile strength of 123.3 MPa. The combination of high in‐plane TC, excellent mechanical flexibility and good electrical insulation jointly justifies the potential application of M‐CoNPs@GNP/c‐CNF TCC films in effective thermal management of flexible electronic products.Highlights CoNPs effectively inhibit GNPs agglomeration. GNPs exhibit hydrophilicity after modification. Modified fillers interact fairly well with the matrix. High tensile strength and exceptional flexibility are achieved. TCC films exhibit both electrical insulation and hydrophobicity.