Filler Morphology Research Articles

Effect of morphology and particle size of bismuth ferrite filler on the surface insulation of epoxy resin composites

AbstractThe morphology and particle size of nanofillers have specific effects on their micro‐distribution parameters in the polymer matrix and macro‐properties of composites. In this study, bismuth ferrite nanoparticles (BFO) with different particle sizes were prepared by the sol‐gel route, and bismuth ferrite nanofibers (fBFO) were synthesized by electrospinning method, then were blended with epoxy resin as a filler to prepare the epoxy composites with multiple filler concentrations. The morphology and crystal structure of the filler were characterized by SEM and XRD. The effect of filler morphology and particle size on the surface insulation of composites was studied. We found that fBFO nanofibers have better dispersion in epoxy matrix, and fBFO/EP composites have more excellent surface insulation properties. Meanwhile, as the particle size of the filler increases, the flashover voltages of the BFO/EP composites increase. Finally, the simulation model of electric field inside EP composites were established and the trap distribution was calculated by isothermal surface potential decay method. The influence mechanism of filler morphology and particle size on the surface insulation properties of EP composites was further analyzed. BFO particles and nanofibers as fillers blended with epoxy resin have a great engineering application potential.

Comparative study on the mechanical, tribological, and thermal properties of POM composites filled with different PTFE

In this study, two different types of polytetrafluoroethylene (PTFE) fillers (i.e. fibrillar and particulate PTFE) were utilized to improve the tribological properties of polyoxymethylene (POM). POM/PTFE composites with various filler contents were tested on a commercial block-on-ring tester. To further probe the tribological properties of POM/PTFE composites under severe sliding conditions, a homemade pin-on-disc tester was employed. Results showed that the lowest coefficient of friction and wear rate are obtained from PTFE particle–filled POM composites at 20 wt%, which is attributed to the formation of uniform transfer film at the sliding interface thanks to the well distribution of PTFE particles. The mass wear rate of POM/PTFE fiber composites is lower than that of PTFE particle–containing counterparts due to the better load transfer of high aspect ratio fibers. The tensile properties of POM/PTFE composites deteriorate with the addition of PTFE fillers; however, the impact strength is significantly enhanced for PTFE fiber filled POM composites. Moreover, both the melting and crystallization properties of POM are affected by the morphology of PTFE fillers and filler concentration, as characterized by differential scanning calorimetry analysis.

Mechanical anisotropy in polymer composites produced by material extrusion additive manufacturing

Extrusion-based additive manufacturing technologies, such as direct ink writing of filled polymer resins, have shown a great potential for the development of printed components with superior structural and functional properties. However, the associated extrusion process induces preferred orientation on high-aspect-ratio filler materials as they extrude through the deposition nozzle, causing strong mechanical anisotropy in printed components. Printing-induced anisotropy is a critical issue that complicates the straightforward design of additively manufactured components. The goal of this work is to gain a better understanding of the anisotropy in printed polymer composites by investigating the effects of filler morphology and print parameters on the mechanical properties of printed composites. Inks are formulated using fumed silica particles or nanoclay platelets as the primary viscosifying agent, and silicon carbide (SiC) whiskers as the primary mechanical reinforcement. Mechanical anisotropy is characterized via 3pt-flexural tests for epoxy ink formulations utilizing fumed silica or nanoclay, with or without SiC whiskers, and printed at three different print speeds, using three different nozzle sizes. Orientation of nanoclay is also characterized using small- and wide-angle x-ray scattering. Results show that smaller nozzle diameters and higher deposition rates lead to greater anisotropy when nanoclay or SiC fillers are utilized, while the use of fumed silica alone results in mechanical behavior that is independent of print parameters and print path. Superior flexure strength values up to 215 MPa are obtained with SiC whisker-reinforced composites when tested parallel to the print direction.

Synergy effect in hybrid nanocomposites based on carbon nanotubes and graphene nanoplatelets

Hybrid nanocomposites reinforced with a mixture of graphene nanoplatelets (GNPs) and carbon nanotubes (CNTs) have shown improvement in filler dispersion while providing a cost-effective alternative to CNT monofiller composites. Depending on their composition, hybrid composites can exhibit electrical performance superior to either of the constituent monofiller composites due to synergistic effects. In this work, we develop a three-dimensional tunneling-based continuum percolation model for hybrid nanocomposites filled with hardcore particles of elliptical GNPs and cylindrical CNTs. Using Monte Carlo simulations, parametric studies of the filler content, composition and morphology are carried out to analyze the conditions required for synergy in percolation onset and electrical conductivity. Our results suggest that for hybrid systems with well-dispersed fillers, the electrical performance is linked to the number of tunneling junctions per filler inside the percolated network of the nanocomposites. More importantly, hybrid composites filled with specific morphology of GNP and CNT, exhibit synergy in their electrical performance when the monofiller composites of each of those exact fillers have similar percolation onset values. The simulations results are in agreement with relevant experimental data on hybrid nanocomposites.

Comparative study of gelatin cryogels reinforced with hydroxyapatites with different morphologies and interfacial bonding

Gelatin cryogels are good candidate scaffolds for tissue engineering because of their interconnected macroporous structure. For bone regeneration, inorganic components are chosen to reinforce gelatin cryogels: (i) to mimic the compositions of natural bone tissue and (ii) to meet the mechanical requirements of bone repairing. Cryogels were prepared from methacrylated gelatin (GelMA) in this study, and hydroxyapatite nanorods (HANRs) with surface-grafted acrylate groups (D-HANRs) were synthesized to reinforce the cryogels, in which, the crosslinking between GelMA and D-HANRs was expected. In parallel, HANRs and hydroxyapatite nanowires (HANWs) were also composited with the GelMA cryogels to investigate the effects of filler morphology and interfacial bonding on the overall properties of the resulting composite cryogels comparatively. All these composite cryogels demonstrated potential as bone repairing materials by displaying excellent performances such as high porosity, appropriate water retention, shape recovery, and fast resilience features, as well as good biocompatibility and cell affinity. In comparison with the HANR composited GelMA cryogel, the HANWs were able to ameliorate the compression and the rheology performances of the resulting composite cryogels more efficiently due to the fact that the one-dimensional HANWs played a bridging role in the gelatin matrix. Among all the preparations, however, it was the D-HANRs that achieved the strongest reinforcement efficiency in mechanical properties because the double bonds on their surface could be photo-crosslinked with GelMA to form interfacial bonding. With these findings, we concluded that it was preferable for inorganic fillers designed for cryogel-type bone repairing materials to be in a one-dimensional morphology with surface functional groups to strengthen their interfacial bonding with the polymeric matrix.

Thermal conductivity and mechanical properties of polyimide composites with mixed fillers of BN flakes and SiC@SiO2 whiskers

AbstractPolyimide (PI) composites with mixed fillers of BN flakes and SiC whiskers exhibit enhanced thermal conductivity and mechanical properties. In order to improve dispersion and interaction of these mixed fillers within the PI matrix, BN flakes were modified by a titanate coupling agent while SiC whiskers were oxidized at 750°C for 60 minutes to produce SiC@SiO2 followed by silane coupling agent modification. PI composites reached a maximum thermal conductivity of 0.95 W/m K at volume fraction of mixed fillers of 27.6 vol% when the weight ratio of BN flakes to SiC@SiO2 whiskers was 1:4. The enhanced thermal conductivity is likely attributed to the formation of heat conductive networks constructed by BN flakes and SiC@SiO2 whiskers and the improved interfacial affinity between fillers and matrix. The optimized Nielsen‐mold confirms the distribution and morphology of fillers affect the thermal conductivity of PI composites. In addition, SiC whiskers enhanced the mechanical property of PI composites and the influence of fillers on the mechanical property was further elaborated.

Enhanced CO2 selectivity of polyimide membranes through dispersion of polyethyleneimine decorated UiO‐66 particles

AbstractBranched polyethyleneimine (PEI) functionalized UiO‐66 were synthesized and used as fillers to fabricated mixed‐matrix membranes (MMMs) for CO2/CH4 separation. The purpose of introducing amino‐functional groups in the filler is to improve the interfacial compatibility of the filler with the polymer through the formation of hydrogen bonds with the carbonyl group of 6FDA‐ODA. Additionally, the amino group can facilitate CO2 transport through a reversible reaction, enhancing the CO2/CH4 separation properties of MMM. The chemical structure and morphology of fillers and membranes were characterized by employing X‐ray photoelectron spectroscopy (XPS), Fourier transform infrared spectrometer (FTIR), X‐ray diffraction (XRD), thermogravimetric (TGA), Derivative thermogravimetry (DTG) and scanning electron microscope (SEM). Furthermore, the effects of filler loading and feed pressure on CO2 permeability and CO2/CH4 selectivity have been investigated. MMMs present higher gas separation performance than pure 6FDA‐ODA due to the presence of amino groups and the improvement of interface morphology. In particular, the MMM with 15 wt% loading of UiO‐66‐PEI shows optimum CO2 permeability of 28.23 Barrer and CO2/CH4 selectivity of 56.49. Therefore, post‐synthetic modification of UiO‐66 particle with PEI is a promising alternative to improved membrane performance.

Ultrafast removal of Cu(II) by a novel hierarchically structured faujasite-type zeolite fabricated from lithium silica fume

Novel hierarchically structured Faujasite Type (FAU) zeolite was fabricated from industrial waste lithium silica fume (LSF) via hydrothermal method without the addition of templates. The FAU zeolites exhibited spherical filler morphology with maximum surface area of 372.8 m2/g, enriched microporosity (0.164 cm3/g), and abundant mesoporosity. Owing to its unique structure, the FAU zeolite allowed ultrafast diffusion and rapid trap of copper ion inside the cages of zeolite crystals, and achieved maximum removal (78.76%) of Cu(II) within the very first 2 min, with adsorption rate constant 5.46–6.27 times greater than that of mesoporous commercial zeolite (CZ) between 15 and 45 °C. The physico-chemical structures of the FAU zeolites were carefully studied by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), Fourier Transform Infrared Spectrometry (FT-IR), surface area analyzer (BET) and X-ray photoelectron spectroscopy (XPS). The maximum qe toward Cu(II) achieved by FAU zeolite (i.e., Z9, S/A of 9) featuring a qe of 94.46 mg/g at 25 °C as per calculated from Langmuir model, which is more than twice amount achieved by CZ (39.15 mg/g). Z9 also showed outstanding selectivity for Cu(II) over various coexisting ions. The saturated Z9 can be regenerated with a mild washing procedure, and the spent zeolite can be reused as effective antibacterial agent. This work proposes a cost-effective and green synthesis route for the hierarchically structured zeolite with high copper selective removal capacity from industrial waste.

Friction, Abrasion and Crack Growth Behavior of In-Situ and Ex-Situ Silica Filled Rubber Composites.

The article focuses on comparing the friction, abrasion, and crack growth behavior of two different kinds of silica-filled tire tread compounds loaded with (a) in-situ generated alkoxide silica and (b) commercial precipitated silica-filled compounds. The rubber matrix consists of solution styrene butadiene rubber polymers (SSBR). The in-situ generated particles are entirely different in filler morphology, i.e., in terms of size and physical structure, when compared to the precipitated silica. However, both types of the silicas were identified as amorphous in nature. Influence of filler morphology and surface modification of silica on the end performances of the rubbers like dynamic friction, abrasion index, and fatigue crack propagation were investigated. Compared to precipitated silica composites, in-situ derived silica composites offer better abrasion behavior and improved crack propagation with and without admixture of silane coupling agents. Silane modification, particle morphology, and crosslink density were identified as further vital parameters influencing the investigated rubber properties.

Influence of Filler Morphology on Electrical Conductivity Variations of Stretchable Wires Printed with Electrically Conductive Pates

Variation in electrical resistivity of stretchable wires printed with electrically conductive pastes containing silver flakes or silver particles was examined during uniaxial cyclic tensile tests. Viscoelastic deformation of the specimens can contribute to suppress increase in electrical resistivity of the wires during loading. Electrical resistivity of the wires significantly increased during unloading not only during loading. This increase in electrical resistivity during unloading is believed to occur related to Mullins effect. Electrical resistivity significantly increases during unloading when the silver micro-particles are used as fillers dispersed in the wires although increase in resistivity can be suppressed during first loading step. Mechanical behavior of the wires that depend on filler morphology plays an important role in determining electrical resistivity variations during the cyclic tensions.

ТЕОРЕТИЧНІ ПЕРЕДУМОВИ ЕКСПЛУАТАЦІЇ КОНСТРУКЦІЙ З МЕТАЛ-СКЛЯНИМИ ЗАХИСНИМИ ПОКРИТТЯМИ В УМОВАХ СУДНОВИХ ВІБРАЦІЙ

The article is devoted to looking for a solution for the scientific and technical issue of reducing vibrations on vessels. It is considered to be achieved with the application of the vibration-absorbing composite coatings. The purpose of the work is to theoretically substantiate the possibility of operation of structures with metal-glass coatings taking into consideration the vibration environment of a vessel. The formulation of the research includes the discovery of the solution for the micromechanics issue set up on the model of a two-layer plate St3 ‒ metal-glass coatings, taking into account their structural features, and experimental tensile tests. The influence of the polydisperse structure of coatings on the mechanisms of absorption of elastic-plastic waves of dynamic oscillations has been analyzed with the help of the analytical description of microdisplacement deformations. The influence of morphology and volume content of glass fillers, specifically hollow glass microspheres, powders of sodium silicate and lead-containing glass on the vibration coefficient, strength limit and yield strength has been investigated. Calculations have shown the feasibility of using metal-glass coatings in conditions of vessel vibration, which is due to the absorption of energy by glass inclusions of spherical and angular shape. It has been experimentally proven that coated plates are slightly inferior in tensile strength to samples with St3; the destruction of coatings occurs between glass inclusions. The obtained results have scientific and practical significance for the design of ship structures using composite materials and coatings.

Comparative study of carbon-based nanofillers for improving the properties of HDPE for potential applications in food tray packaging

High-density polyethylene (HDPE)/carbon filler composites for potential applications in food tray packaging were prepared by melt compounding HDPE with one-dimensional (1D)-multiwalled carbon nanotubes (MWCNT), two-dimensional (2D)-graphene oxide (GO) and three-dimensional (3D)-carbon black (CB) on a twin-screw extruder. The morphology of fillers inside the HDPE matrix was characterized and correlated to the mechanical, thermal and barrier properties of the nanocomposites. The results showed the distinct effect of CB on the mechanical, thermal and barrier properties of HDPE from MWCNT and GO. The morphological analysis revealed uniform dispersion for all the fillers, but the agglomerate formation was a lot more evident in MWCNT-based nanocomposites. Ball milling solved the large agglomerate formation for MWCNT and produced nanocomposites with improved mechanical properties. In comparison to 1D and 2D nanofillers, the 3D-CB filler showed remarkable contribution to tensile toughness but caused a reduction in barrier properties of HDPE, the increase in tensile toughness was attributed to uniform dispersion of the filler, enhanced mechanical interlocking between filler and polymer, appearance of high degree of crazing on tested samples and increase in nanocomposite internal temperature during tensile testing.

Synthesis and swelling behavior of environmentally friendly starch-based superabsorbent hydrogels reinforced with natural char nano/micro particles

Herein, the proficiency of natural char (NC) as cost-effective and biocompatible filler for the synthesis of high-performance starch-based superabsorbent composites was evaluated. To this goal, NC powder, ball-milled natural chars (BMNCs) and chemically modified NC nanoparticles (NCNPs) were synthesized and then utilized as fillers for preparation of starch-g-poly(acrylic acid-co-acrylamide) superabsorbent composites. The morphology and surface functionalities of the as-synthesized fillers and their composites were scrutinized using FTIR, FESEM, elemental mapping, AFM, Boehm titration and TGA analyses. The results proved that the composite performance was controlled by the filler’s properties (i.e., morphology, size, surface chemistry and functionalities) and NCNPs with the smallest particle sizes (14.8 ± 3.0 nm) and the highest oxygen functionalities was selected as the best filler candidates. Coexistence of the physical and covalent cross-linkage in the NCNPs/Hydrogel nanocomposite could be proposed as a reason for its two-fold water absorbency (389.9 g/g) in comparison with the neat hydrogel (202.1 g/g). However, the addition of NC and BMNC in the polymer matrix could not significantly improve the water absorption performance of the composite. Absorbency under load (AUL) results showed that the gel strength of samples displayed the following descending order of NCNPs/Hydrogel > BMNC/Hydrogel > NC/Hydrogel > neat hydrogel > commercial hydrogel. All synthesized starch-based superabsorbent (nano)composites showed a Fickian water diffusion mechanism and pseudo-second-order swelling kinetic model. Moreover, after 14 days, NCNPs/Hydrogel nanocomposite showed three-fold water-retention (%) capability compared with the neat hydrogel (23.1 % vs. 7.1 %, respectively).

Experimental investigation of a hybrid nickel-carbon black polydimethylsiloxane conductive nanocomposite

This paper presents an experimental investigation of single and hybrid carbon black and spiky nickel-filled conductive composite to understand the synergy effect when different types and shapes of fillers are combined in a silicone polymer matrix. The electrical and mechanical properties of the conductive composites are measured under a compressive loading cycle. The results showed that the electrical properties of the hybrid conductive polymer composites have a better repeatability at low filler ratio as compared to the virgin nickel or carbon black composite. The new hybrid composite piezoresistive behavior is similar to a high filler ratio nickel composite. This study provided insights to develop a tailored conductive composite with a low mass-ratio and different morphology of fillers.

Silver (Ag) nanoparticle-decorated expanded graphite (EG) epoxy composite: evaluating thermal and electrical properties

Synthesized expanded graphite (EG) was decorated with Ag nanoparticles using solid-state decomposition by a simple ‘mix and heat’ technique. The epoxy composite was fabricated by a stir casting method with an ultrasonic procedure in order to enhance the thermal conductivity (TC). The morphology of filler (EG–Ag) studied under X-ray diffraction (XRD) technique and scanning electron microscopy (SEM) confirms the attachment of Ag nanoparticles on EG surfaces. The TC of the composite containing 10 wt% of EG–Ag hybrid filler (EG–Ag(10)-Ep(90)) measured using guarded heat flow meter technique was found to be 2.52 W/mK, which is almost 13-fold enhancement as compared to the neat epoxy. The thermo-gravimetric analysis (TGA) of EG–Ag(10)-Ep(90) confirmed thermal stability which enhanced from 289 to 327 °C at 5% weight loss, in N2 atmosphere. The improvement in TC was ascribed to the synergistic effect of micro-nano (EG–Ag) hybrid filler, in which Ag nanoparticles acted as ‘spacer’ between EG threads by reducing interfacial Kapitza resistance as evidenced from fracture surface analysis. After attaining 3D percolation limit, the hybrid composite at 10% filler fraction (EG–Ag) entered the electrical conductivity of the semiconducting range which was enhanced by fourteen orders from neat epoxy.

Electrical Properties of Silver-Attached Amine Functionalized Carbon Black/Polyethylene Terephthalate Fibers Prepared by Melt-Spinning.

In this study, amine functionalized carbon black (ABCB) was synthesized using 4-aminobenzoic acid in a phosphoric acid (PPA)/phosphorus pentoxide (P2O5) medium, and silver-attached carbon black (Ag-ABCB) was prepared by reducing AgNO3 with NaBH4 in the presence of ABCB in ethanol. Elemental, thermogravimetric, and Fourier transform-infrared analyses showed that carbon black (CB) had a well-functionalized 4-aminobenzoic acid. In addition, X-ray photoelectron spectroscopy and X-ray diffraction were used to examine the crystal structure of Ag nanoparticles. Conductive fibers were prepared by melt-spinning using ABCB, Ag-ABCB as a conductive filler, and polyethylene terephthalate (PET) as a polymer matrix. Results confirmed that the fiber that had Ag-ABCB as a conductive filler exhibited the best electrical conductivity. The dispersibility and morphology of the conductive filler in the PET matrix were confirmed through scanning electron microscopy analysis, and Ag-ABCB was the most uniformly dispersed filler in the PET matrix, with good structure.

Printer orientation effects and performance of novel 3-D printable acrylonitrile butadiene styrene (ABS) composite filaments for thermal enhancement

This study presents a fabrication method to create various 3-D printable acrylonitrile butadiene styrene (ABS) composite filaments designed for thermal applications and improved heat transfer versus typical plastics. Thermal conductivity data and scanning electron microscope (SEM) images are presented and discussed to discern filler morphology and alignment. The effects of different printer orientations on thermal conductivity are established. Results indicate nanotube and flake fillers align with filament print direction, and structures printed in the vertical print orientation can improve thermal conductivity by as much as 70% over a horizontal print orientation.

Lignin from second-generation biorefinery for pressure-sensitive adhesive tapes

In this work, the potential of lignin as a filler additive and anti-aging agent in a pressure-sensitive adhesive (PSA) based on natural rubber (NR) was investigated. Herein, different approaches to incorporate lignin into NR matrix by adaptation of a two-step compounding process were evaluated. At first, a twin-screw extruder (TSE) was utilized to prepare pre-formulations followed by the secondary finalization of adhesive mass inside a planetary roll extruder (PRE). For the industrial production of PSAs, the adhesive mass is required to have well-distributed additive materials and adequate adhesion, cohesion, and longevity. The impact of the added lignin was evaluated concerning optical appearance, compatibility between lignin and rubber/resin, adhesion performance, shear strength, thermal stability, antioxidant capability, dynamic-mechanical behavior, aging behavior at elevated temperature and under UV exposure, and filler morphology. It was found that the PSAs including aquasolv (AS) lignin after the spray-drying post-treatment exhibited excellent thermal, mechanical, and antioxidative properties. Thus, it was shown that the sustainably producible lignin can be utilized both as filler and antioxidant in natural rubber-based pressure-sensitive adhesive masses with comparable performance properties as commercially available products.

Thermal, nanoindentation and dielectric study of nanocomposites based on poly(propylene furanoate) and various inclusions

In this work, we investigate polymer nanocomposites (PNCs) based on a poly(propylene furanoate) (PPF), a relatively new biobased polymer, envisaged for various application, e.g. exploiting its exceptional gas barrier properties. PPF exhibits extremely slow crystallization and subsequently poor mechanical performance, therefore, targeting at improving its properties, PPF is filled here with five fillers of different geometries, i.e. Carbon Nanotubes (CNT), Halloysite nanotubes, Graphene nanoplatelets, and two Montomorillonite (MMT) clays. Crystallization, glass transition and mechanical performance are investigated employing differential scanning calorimetry (DSC) and mechanical nanoindentation tests supplemented by X-ray diffraction (XRD), on both amorphous and semicrystallized samples. Moreover, we attempt to investigate the structure (filler morphology, semicrystalline morphology) / properties relationship also in combination with recording molecular dynamics via broadband dielectric spectroscopy (BDS). For the fixed filler content of 1 wt%, the majority of the inclusions were found to increase the rate of PPF crystallization at the relatively mild temperature of 100 °C, which is desirable in industrial polymer processing. However the impact of the fillers on the degree of crystallinity is quite low, the latter being expected to correlate with semicrystalline morphology alternations in the composites as compared to the unfilled PPF. The nanoindentation tests showed clear beneficial effects of the various inclusions on the elastic modulus and indentation hardness, being, as expected, more profound in the case of semicrystallized PPF matrix. Additionally, the full-temperature dielectric-calorimetric map was constructed, showing that the effects on local and segmental polymer dynamics (β and α relaxations, respectively) by the PNC composition are insignificant whereas those by crystallization are dominant. Finally, an additional filler-related process (αf relaxation) was recorded in two cases of PNCs, showing non cooperative character and independency from crystallization, the origins of this process being still under investigation.

Surface roughness and filler particles characterization of resin-based composites.

The purpose of this study was to evaluate the surface roughness (Ra), and the morphology and composition of filler particles of different composites submitted to toothbrushing and water storage. Disc-shaped specimens (15 mm × 2 mm) were made from five composites: two conventional (Z100™, and Filtek™ Supreme Ultra Universal, 3M), one "quick-cure" (Estelite ∑ Quick, Tokuyama), one fluoride-releasing (Beautiful II, Shofu), and one self-adhering (Vertise Flow, Kerr) composite. Samples were finished/polished using aluminum oxide discs (Sof-Lex, 3M), and their surfaces were analyzed by profilometry (n = 5) and scanning electron microscopy (SEM; n = 3) at 1 week and after 30,000 toothbrushing cycles and 6-month water storage. Ra data were analyzed by two-way analysis of variance and Tukey's test (α = 0.05). Filler particles morphology and composition were analyzed by SEM and X-ray dispersive energy spectroscopy, respectively. Finishing/polishing resulted in similar Ra for all the composites, while toothbrushing and water storage increased the Ra of all the tested materials, also changing their surface morphology. Beautifil II and Vertise Flow presented the highest Ra after toothbrushing and water storage. Filler particles were mainly composed of silicon, zirconium, aluminum, barium, and ytterbium. Size and morphology of fillers, and composition of the tested composites influenced their Ra when samples were submitted to toothbrushing and water storage.