Amount Of Filler Research Articles

Application of a New Carbon Black Filler in SBR Composites

The microstructure and properties of a new type of carbon black produced by a domestic company through a new process were systematically characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), Raman spectroscopy, and X-ray diffraction (XRD). The vulcanization properties, mechanical properties, and electrical conductivity of the new carbon black with different filler amounts were investigated in styrene butadiene rubberstyrene–butadiene rubber (SBR), using the traditional reinforcing filler N660 carbon black as a control. The experimental results demonstrate that the new carbon black exhibits a stratified structure with a specific surface area of 345.96 m2/g, and its particle size distribution is primarily concentrated within the 0.1–1 μm range. When the filling ratio was 30 phr/100 phr, the tensile strength of SBR composites filled with the new carbon black increased by 12.3% and the tear strength increased by 9.6% compared with those filled with N660 carbon black. In summary, the new carbon black can significantly improve the comprehensive performance of SBR composites and reduce the production cost. This provides a new type of material for the rubber industry that takes into account both economy and performance while also providing reference data for basic research in the field of SBR.

Thoughts on the Service Life of Internally Cured Concrete Considering ASR and FT

Internal curing has been proven as a solution to reduce early-age shrinkage and related cracking in concrete. Internal curing can reduce the risk of built in stress, cracking, and curling in concrete pavements. However, the benefits of internal curing go beyond just shrinkage and cracking mitigation. Research by the author’s has shown the incorporation of fine lightweight aggregate-FLWA can significantly reduce the risk of deleterious alkali-silica reaction. When the FLWA replaces a reactive aggregate a dilution effect occurs, but other benefits also exist. The curing provided by internal curing can react a greater percentage of cementitious material allowing a reduction in cement and an increase in the amount of binder fillers thereby reducing the alkali loading of the mixture. Additionally, the internal curing was shown to reduce the pH of the internal concrete pore solution and led to a refinement of the interfacial transition zone, possibly due to a pozzolanic reaction. The FLWA provides a porous inclusion which appears to enable a reaction product, similar to ASR gel to form however with limited expansion.

Electrically conducting porous hydrogels by a self-assembled percolating pristine graphene network.

This study introduces a method for synthesizing electrically conductive hydrogels by incorporating a self-assembled, percolating graphene network. Our approach differs from previous approaches in two crucial aspects: using pristine graphene rather than graphene oxide and self-assembling the percolation network rather than creating random networks by blending. We use pristine graphene at an oil-water interface to stabilize a water-in-oil emulsion, successfully creating hydrogel foams with conductivities up to 15 mS m-1 and tunable porosity. Our approach avoids the need for the conductivity-degrading oxidation process to form GO and decreases the amount of graphitic filler needed for percolation, leading to superior mechanical properties. The concentration of monomer and graphite in the emulsion was optimized to control the cell size, stability, and swelling behavior of the final hydrogels, offering versatility in structure and functionality. Electrical conductivity and thermogravimetric analysis (TGA) confirmed the stability and conductive properties imparted by the graphene network. This method demonstrates a cost-effective route to conductive hydrogels, making them promising candidates for applications in sensors, energy storage, bioelectronics, and other advanced technologies.

Upcycling Calcium Carbonate as an Alternative Filler in Layered Wood Composite Technology.

Chicken eggshells are a useful waste that may be used somewhere rather than being placed in landfills. They are created in poultry hatcheries, the food sector (making pasta, cakes, and egg products), or our homes. In this project, this study aimed to investigate the possibility of producing plywood using a filler in the gluing process in the form of ground eggshells. This study includes the production of plywood with 0, 1, 5, 10, and 20 parts by weight (pbw) of eggshell filler (called E0, E1, E5, E10, and E20, respectively) and one reference variant with rye flour (10 pbw; hereafter called REF10). This research also includes investigating the produced panels' selected physical and mechanical properties. The results show that chicken eggshells can be used to produce plywood if the right amount of filler is chosen to improve specific mechanical and physical properties. Promising properties were obtained in the determination of the modulus of elasticity under bending (MOE) for samples E5 (11,310 N mm-2) and E10 (11,394 N mm-2) and modulus of rupture (MOR) for sample E5 (130 N mm-2). The results for the internal bond (IB) show that the addition of 5 pbw of filler in the form of ground shells shows good properties with as much as 5.23 N mm-2, but still, the reference sample with the addition of filler in the form of rye flour has higher results of 6.22 N mm-2. In the test of water absorption of fillers, the absorption of calcium carbonate is 207% and is lower than that of rye flour (224%). For the swelling thickness results, the E10 sample showed the weakest results of 7.6% after 2 h and 8.9% swelling after 24 h.

Evaluation of mechanical properties and ion-releasing of 3D printing resins containing S-PRG filler: A preliminary study.

This study aimed to evaluate ionic release, flexural strength and water absorption of UDMA resins containing 0-30 wt% surface pre-reacted glass-ionomer (S-PRG) filler fabricated by a DLP 3D printer. Release of Al, B, Na, Sr and F ions were measured by inductively coupled plasma (ICP) and an ion meter. Flexural strength test and water absorption measurements were performed according to the International Organization for Standardization (ISO) 4049 standard and ISO 1567 standard, respectively. Sr ions were released the most, followed by F, B, Na and Al ions. The highest flexural strength was recorded with the S-PRG filler amount 0 wt%, followed by the S-PRG filler amounts 30, 20 and 10 wt%. Water absorption after one week was below the 32 µg/mm3 mark specified by ISO 1567. The release of ions was confirmed using UDMA-based photopolymerized resin containing S-PRG filler. Furthermore, the results suggest that this resin could be used for provisional restoration.

Improving the thermophysical properties of polymer composites

To improve the thermophysical properties of polymer composites, their physicochemical modification was carried out by introducing a microdispersed filler of synthesised aluminium-copper charge into the epoxy resin. Based on the dynamics of thermophysical properties depending on the amount of filler in the synthesised aluminium-copper charge, the optimal content of the additive in the epoxy compound was determined, which is 2...2.5 mass%. The introduction of filler into the epoxy oligomer ensures the production of composites with maximum values of thermal properties. The mechanism of formation of a heterogeneous structure of composites in the presence of microdispersed filler is substantiated. There are three structural levels that are formed after the polymerisation of the material: micro-, meso- and macrostructure. It is shown that in the formation of heterogeneous composites, there is a hierarchical combination of structural levels, and the dominant influence of one of them is determined by the nature and content of the filler. It is substantiated that the structure and properties of the composites are determined by the course of structure formation processes: within a single level, between different levels in a cluster, and between clusters.

The Influence of the Solid Phase on the Properties of Foam Concrete

An overview of literary sources related to the formation and development of the technology of aerated concrete is given. It is shown and systematized in which directions scientific research aimed at improving their functional properties was conducted. It is noted that almost all researchers associate the dependence of the properties of porous concrete with the character of their porosity. The conducted analysis allowed the authors to hypothesize that the properties of aerated concrete are exclusively determined by the nature of the distribution of the solid phase, that is, by the nature of its structure. Determination of the influence of the solid phase and its nature on the properties of aerated concrete is devoted to experimental studies. They were conducted in two stages. At the first, when applying physical modeling, the effect of the total porosity and water consumption of the dry mixture on the change in the nature of the solid phase of the model was studied. Internal interfaces between structural elements are taken as characteristics of the solid phase - their total length and width. It is shown that the water consumption of the mixture has different effects on materials with a dense and porous structure. At the next stage of experimental research, the influence of the water consumption of the mortar mixture on its strength (strength of the matrix material) and the strength of foam concrete was studied. The initial rheological conditions of the formation of the structure were changed by changing the size and amount of filler, changing the amount of liquid and plasticizing additives. The results of the experiments confirmed that the initial rheological conditions have different effects on the materials of dense and porous structure. Under certain conditions, in materials with a porous structure (in foam concrete), an increase in the water-solid ratio leads to an increase in the strength of concrete. Which indicates that with such water consumption, more favorable conditions are created for the formation of a porous structure, which is reproduced on the character of the solid phase. The given results confirm the given hypothesis and can be used in the synthesis of new building materials, including with the use of artificial intelligence.

Progress of material degradation: metals and polymers in deep-sea environments

Abstract Given the critical need for ocean exploration, improving the durability of materials in the deep-sea has become a paramount concern. The harshness of deep-sea, such as high pressure, variable seawater flow rates, and corrosive media, lead to premature aging and failure. This work examines the utilization of metals and polymer coatings in deep-sea applications, detailing the characteristics of the deep-sea and its influence on these materials. In particular, chloride ions in seawater pose significant hazards to metal corrosion, which is the main reason for metal failure. Then, the degradation process and the latest research advances of various materials in the deep-sea environment are summarized, and the failure mechanism of the metal/coating system in the deep-sea is analyzed. It was found that the failure of polymer coatings can be divided into three processes, and adding an appropriate amount of fillers to the coating (such as adding 0.2 % graphene to water-based polyurethane) can extend the service life of the coating. Finally, the development trend of the company in the future is predicted. It has guiding and reference significance for the study of the failure behavior of metals and polymers in the deep-sea environment.

Improving water barrier properties of starch based bioplastics by lignocellulosic biomass addition: Synthesis, characterization and antibacterial properties.

Global population growth has led to an increase in the demand for polymers, along with concerns about environmental pollution caused by solid polymers (such as consumer plastics), as well as the threat of global warming resulting from the production of polymer feedstock. Therefore, the polymer industry must develop sustainable and innovative strategies. The present study focuses on testing the potential of corn starch (CS) to produce bioplastic films and the impact of olive pits powder (OPP) addition, a natural agricultural waste material mainly containing lignocellulose, as filler on their properties. The developed bioplastic films containing starch, plasticizer, crosslinker and different amounts of OPP natural filler were prepared by casting solvent method according to a "green chemistry" process. The chemical, morphological, and thermal characterization of the prepared films was investigated using transformed infrared spectroscopy (FTIR), X-rays diffraction (XRD), atomic force microscopy (AFM) and thermogravimetric analysis (TGA). The physico-chemical, optical, water and oxygen barrier properties of the developed bioplastic films were evaluated as a function of OPP concentrations. Moreover, attention was paid to evaluate their biodegradability and their antibacterial activity. The addition of OPP from 10 to 70% w/w led to an improvement of oxygen and water barrier properties (contact angle, water adsorption and moisture adsorption) due to specific interactions between starch matrix and lignocellulosic biopolymers present in OPP filler. The soil-biodegradability tests revealed that the control film was totally decomposed and the weight loss of all other films was upper than 70% after only 14days of exposure to soil. Antibacterial tests showed that the developed bioplastic films had an affective activity against both gram positive and gram negative bacteria strains.

Studies on the Enzymatic Degradation Process of Epoxy-Polyurethane Compositions Obtained with Raw Materials of Natural Origin.

Along with the development of technology and the increasing consumption of polymeric materials, which have become an integral part of man's everyday life, problems related to their disposal are arising. The presented research concentrates on the studies on the enzymatic degradation of selected epoxy-polyurethane materials filled with 2 or 5 wt.% of waste unmodified or chemically modified through mercerization wood flour. Composites, subjected to the degradation process, contained up to 60% of raw materials of natural origin. The enzymatic degradation was carried out for 28 days, in three environmental conditions, differing in the type of applied buffer, pH, process temperature, the amount, and the type of applied enzyme. In this study, the influence of two lipases was tested (specifically: lipase of microbiological origin-Rhizopus Oryzae Lipase, and one of animal origin-Porcine Pancreas Lipase). There were seven compositions tested, based on the polyaddition product of epoxidized soybean oil with bisphenol A, differing in the amount of filler and the type of modification to which wood flour was subjected before the application in the polymer composite. After enzymatic degradation, the greatest progress of biodegradation was observed at T = 30 °C, in a complex phosphate buffer with pH = 6.8, in the presence of the Porcine Pancreas enzyme. Under these conditions, a slightly smaller effect was also observed in the presence of the Rhizopus Oryzae enzyme. At the same time, the compositions containing mercerized wood flour turned out to be the most susceptible to biodegradation with the above-mentioned enzymes. After conducting the process in the full 4-week cycle numerous changes were noticed within the tested sample, such as (1) 7.0 %wt. of the overall weight loss of samples, (2) reducing the value of the static contact angle (e.g., from 116.7° before degradation to 27.2° at the end of the study), and (3) morphological appearance of the sample (sample's surface had suffered erosion noticed as smoothest roughnesses and numerous empty holes throughout its entire volume), concerning sample's condition before enzymatic degradation.

Effect of Cement Substitution with Mineral Fillers on NOx Air-Purification Efficiency and Photocatalytic Reaction Selectivity of Nano-TiO2-Modified Cementitious Composites.

This research investigated the properties of photocatalytic cementitious composites, including their air-purification efficiency. A method of characterizing the removal of airborne pollutants (nitrogen oxides), simulating the actual NOx concentration and irradiation conditions in Warsaw, Poland, in the autumn/winter season was established. The study analyzed the impact of changes in the composition of cement mortars-partial substitution of the binder with mineral fillers-on the properties of the external photoactive surface of the composite. The designed experimental plan included both quantitative and qualitative variables (type and amount of fillers used). It was found that the photocatalytic performance of the composite was correlated with its pore total content and pore size distribution-the higher the content of mineral fillers, the lower the porosity and the less effective its photocatalytic properties. The selectivity of the photocatalytic NOx reactions also deteriorated as the content of the mineral fillers increased. The study confirmed the validity of increasing the binder content in cementitious composites to enhance their photocatalytic performance.

Study on the Properties and Mechanism of m‐FACs/f‐Fe3O4/Epoxy Wear‐Resistant Magnetic Coating

ABSTRACTIn view of the wear problem of key parts of magnetic fluid seal device, epoxy resin (EP) composite coatings reinforced with Fe3O4 and fly ash cenospheres (FACs) were fabricated successfully. The structural and morphological features of the fillers and the composite coatings were characterized by Fourier transform infrared and scanning electron microscopy. CFT‐I material surface performance comprehensive tester was used to investigate the tribological behaviors of the as‐prepared composite coatings. Vibrating sample magnetometer was used to investigate the coatings' magnetic property. The formation mechanism of the composite coating was analyzed by the infrared spectrum results combined with molecular dynamics simulations. The results demonstrated that adding a certain amount of double fillers will have a synergistic effect, and its mechanical properties are better than those of single fillers. The tribological property of the m‐FACs/f‐Fe3O4/EP composite coatings was optimal under magnetic fluid friction, which is about an order of magnitude lower than the wear rate under dry friction. The saturation magnetization of the m‐FACs/f‐Fe3O4/EP composite coating is 2.77 emu/g, and the magnetic susceptibility reaches 4.64 × 10−4 m3/kg. Therefore, the m‐FACs/f‐Fe3O4/EP composite coating will be expected to solve the wear problem of equipment components in complex environments of magnetic field and friction.

Experimental Investigation of Indirect Tensile Strength of Hot Mix Asphalt with Varying Hydrated Lime Content at Low Temperatures and Prediction with Soft-Computing Models

If asphalt pavements are exposed to cold weather conditions and high humidity for long periods of time, cracking of the pavement is an inevitable consequence. In such cases, it would be a good decision to focus on the filler material, which plays an important role in the performance variation in the hot asphalt mixtures used in the pavement. Although the use of hydrated lime as a filler material in hot asphalt mixtures is a common method frequently recommended to eliminate the adverse effects of low temperature and to keep moisture sensitivity under control in asphalt pavements, the sensitivity of the quantities of the material cannot be ignored. Therefore, in this study, an amount of filler in the mixture was replaced with hydrated lime (HL) filler additive at different rates of 0%, 1%, 2%, 3% and 4%. These asphalt briquettes, designed according to the Marshall method, have optimum asphalt contents for samples with specified HL content. In this study, where the temperature effect was examined at five different levels of −10 °C, −5 °C, 0 °C, 5 °C and 25 °C, the samples were produced in two different groups, conditioned and unconditioned, in order to examine the effect of water. The indirect tensile strength (ITS) test was applied on the produced samples. Experimental study showed that HL additive strengthened the material at low temperatures and made it more resistant to cold weather conditions and humidity. In the second part of the study, two different prediction models with varying configurations were introduced using nonlinear regression and feed-forward neural networks (FFNNs) and the best prediction performance among these was investigated. Examination of the performance measures of the prediction models indicated that ITS can be accurately predicted using both methods. As a result of comparing the developed models with the experimental data, the model provides significant contributions to the evaluation of the relationship between the ITS values obtained with the specified conditioning, temperature changes and HL contents.

Surgical and Non-Surgical Approach for Tear Trough Correction: Fat Repositioning Versus Hyaluronic Acid Fillers.

Objective: This paper compares two popular techniques for tear trough correction-fat repositioning and hyaluronic acid (HA) fillers-highlighting their efficacy, safety profiles, patient satisfaction, and associated complications. Methods: A narrative review of 20 studies comparing fat repositioning and HA fillers was conducted, focusing on parameters such as duration of results, volume restoration, complication rates, and patient satisfaction. Results: Fat repositioning provides long-lasting results but carries higher surgical risks compared with HA fillers. The transconjunctival approach is suitable for patients with minimal skin excess. The supraperiosteal plane allows for a quicker procedure and, despite postoperative edema and temporary irregular contouring, shows no difference in final cosmetic outcomes compared with other planes. Internal fixation reduces the risk of fat relapse and skin scarring but carries the risk of suboptimal positioning. HA fillers offer immediate, minimally invasive results but require periodic maintenance. The use of a cannula reduces the risk of vascular occlusion. Combining a high G' filler for the midface with a low G' with low hydrophilicity for the tear trough reduces the amount of filler needed and prolongs the results. Both surgical and non-surgical methods are effective, depending on patient needs and anatomical considerations. Conclusions: Fat repositioning is ideal for patients seeking long-term correction and are willing to undergo surgery, while HA fillers suit those preferring non-invasive treatments with customizable, short-term effects. Both techniques have pros and cons that must be matched to patient goals and conditions.

Optimization of Starch-Based Bioplastic from Sweet Potato using Box-Behnken Design with Plasticizer and Filler for Reduced Water Absorption

Plastic is a ubiquitous material used in a wide range of applications, but its disposal has become a significant environmental concern. Bioplastics, which offer several advantages over conventional plastics, including a smaller carbon footprint, greater biodegradability, and adaptability, are being explored as a potential alternative. Among the bioplastics, starch-based polymers have gained significant attention due to their natural abundance, biocompatibility, low cost, and renewability. In this study, a starch-based bioplastic was developed using glycerol and sorbitol as plasticizers and wood dust as a filler through the casting method. Starch was extracted from sweet potato (Ipomoea batatas). The optimal conditions for preparing the bioplastic with minimum water adsorption were determined using a three-level Box-Behnken design. The amount of starch, plasticizer, and filler were the key parameters for this study. The percentage of water absorption was determined by immersing the prepared bioplastic in distilled water for 24 hours and weighing it. The result of the Fourier Transform Infrared (FTIR) spectroscopy of extracted starch showed a similar observation peak pattern when compared to the FTIR spectrum of commercial starch. The linear response model produced a good coefficient of determination (R2 = 0.8237), indicating that the chosen parameters implicitly affect the percentage of water absorption. The prediction percentage of water absorption after optimization is 20.069 with a desirability value of 0.806. This study shows that the response surface approach helps in determining the optimum conditions for the minimum percentage of water adsorption from starch-based bioplastic.

Copper selenide as a facile nanomaterial for triboelectric nanogenerator: Self-powered Braille code keyboard

The development of triboelectric nanogenerators (TENGs) for sustainable energy harvesting has garnered significant interest, especially in integrating advanced materials to enhance device performance and exploring applications. Herein, the present study investigates the use of copper selenide (Cu2Se) as a robust material for TENGs fabrication. Cu2Se nanorods are synthesized using a facile hydrothermal method and subsequently embedded in a polyvinyl alcohol (PVA) matrix to form a nanocomposite, which is then utilized as tribopositive film. The procured Cu2Se and nanocomposites with varying filler quantities (0.1, 0.2, 0.4, and 0.8 wt%) are analyzed using powder X-ray diffraction, scanning electron microscopy, dielectric measurements, Fourier transform infrared spectroscopy, and ultraviolet–visible spectroscopy to evaluate their structural, morphological, dielectric, and optical properties, and their impact on TENG performance. Interestingly, the device with 0.2 wt% Cu2Se generated peak-to-peak voltage and current of 394.35 V and 83.45 µA respectively, which is about 2.5- and 41-times higher output compared to pristine PVA-TENG. Integrating Cu2Se as filler enhances charge generation, transfer, and retention, due to increased surface roughness, and ability to facilitate better charge separation within the polymer matrix leading to more efficient energy conversion in TENGs. In practical demonstration, the optimized PVA@ Cu2Se-TENG is employed as a self-powered Braille keyboard to generate electrical signals from mechanical interactions, offering a promising solution for energy-efficient, user-friendly Braille technology. Thus, the current study highlights the synergistic effects of integrating Cu2Se with polymer, resulting in enhanced triboelectric performance for innovative energy harvesting applications and self-powered sensory devices.

Sewage sludge ash as filler in asphalt mastic: Low-temperature towards high-temperature performance

The sewage sludge ash (SSA) is characterized as a by-product used in the pavement industry to mitigate the environmental risks, enhance the landfill capacity and conserve the non-renewable resources. This research utilized SSA as a filler substitute in asphalt mastic, and its performance-based properties from low towards high temperatures were evaluated. For this goal, the physical and chemical properties of SSA and rock powder (used as base filler) were determined using BET surface area measurement, X-ray fluorescence, and scanning electron microscopy tests. The performance of base and SSA-modified asphalt mastics in four filler/bitumen weight ratios (0.6, 0.8, 1, and 1.2) was investigated using dynamic shear rheometer, multiple stress creep and recovery, linear amplitude sweep, and bending beam rheometer tests across a wide temperature range. The results indicate that SSA has a higher specific surface area, better bitumen absorption, and lower density compared to the base filler. Additionally, unlike the acidic nature of the base filler, SSA possesses strong basic properties, leading to a stronger chemical bond with bitumen and enhanced resistance to aging, particularly at high temperatures. Moreover, the lower density of SSA escalates the amount of filler per unit volume of the SSA-modified asphalt mastic, leading to the increased stiffness and elasticity. This trend improves resistance to permanent deformation and cracking at medium temperatures, although it has an adverse effect on performance of mastic at low temperatures. Moreover, due to the improved performance of SSA-modified asphalt mastic, this study can contribute to the sustainable development of the pavement industry.

From nano to macro in graphene-polymer nanocomposites: A new methodology for conductivity prediction

A two-step approach is proposed to forecast the conductivity of graphene polymer composites using simple models reflecting the tunneling mechanism and interphase part. Firstly, graphene and the adjacent interphase are presumed as figurative particles, and their conductivity is estimated. In the second stage, the conductivity of the nanocomposite containing figurative particles is predicted, considering the tunneling size between adjacent particles. The advanced methodology is used to forecast the conductivity for real examples. Additionally, the implications of all terms on the nanocomposite conductivity are assessed and explained. The estimations of conductivity acceptably agree with the measured data, which justifies the predictability of the suggested methodology. Thick interphase and short tunnels produce desirable conductivity, because they positively influence the net dimensions and tunneling resistance. Among the studied parameters, the thicknesses of graphene nanosheets and interphase have the highest impacts on the nanocomposite conductivity. The highest conductivity of nanocomposite as 7 S/m is obtained by the thickest interphase (ti = 10 nm) and the thinnest nanosheets (t = 1 nm), while t > 2 nm or ti < 5.5 nm cannot improve the conductivity. Furthermore, graphene volume fraction of 0.03 with the graphene diameter of 4 μm maximizes the nanocomposite conductivity to 3 S/m, but less filler amount and shorter nanosheets weaken the conductivity of nanocomposites.

Early Biological Response to Poly(ε-Caprolactone)/Alumina-Toughened Zirconia Composites Obtained by 3D Printing for Peri-Implant Application.

The improvement of the mucosal sealing around the implant represents a challenge, one that prompted research into novel materials. To this purpose, a printable poly(ε-caprolactone) (PCL)-based composite loaded with alumina-toughened zirconia (ATZ) at increasing rates of 10, 20, and 40 wt.% was prepared, using a solvent casting method with chloroform. Disks were produced by 3D printing; surface roughness, free energy and optical contact angle were measured. Oral fibroblasts (PF) and epithelial cell (SG) tests were utilized to determine the biocompatibility of the materials through cell viability assay and adhesion and spreading evaluations. The highest level of ATZ resulted in an increase in the average roughness (Sa), while the maximum height (Sz) was higher for all composites than that of the unmixed PCL, regardless of their ATZ content. Surface free energy was significantly lower on PCL/ATZ 80/20 and PCL/ATZ 60/40, compared to PCL and PCL/ATZ 90/10. The contact angle was inversely related to the quantity of ATZ in the material. PF grew without variations among the different specimens at 1 and 3 days. After 7 days, PF grew significantly less on PCL/ATZ 60/40 and PCL/ATZ 80/20 compared to unmixed PCL and PCL 90/10. Conversely, ATZ affected and improved the growth of SG. By increasing the filler amount, PF cell adhesion and spreading augmented, while PCL/ATZ 80/20 was the best for SG adhesion. Overall, PCL/ATZ 80/20 emerged as the best composite for both cell types; hence, it is a promising candidate for the manufacture of custom made transmucosal dental implant components.

Kinetic of Light Transmission during Setting and Aging of Modern Flowable Bulk-Fill Composites.

The current development of dental materials aims to improve their properties and expand their clinical application. New flowable bulk-fill composites have been released which, unlike what was previously common in this material category, are intended to be used alone and without a top layer, in various cavities. The study compares their kinetic of light transmission during monomer-to-polymer conversion on a laboratory-grade spectrometer, as well as their elastoplastic and aging behavior under simulated clinical conditions. Major differences in the kinetic of light transmission was observed, which is related to the degree of mismatch between the refractive indices of filler and polymer matrix during polymerization and/or the type of initiator used. Compared to the literature data, the kinetic of light transmission do not always correlate with the kinetic of functional group conversion, and therefore should not be used to assess polymerization quality or to determine an appropriate exposure time. Furthermore, the initial mechanical properties are directly related to the volumetric amount of filler, but degradation during aging must be considered as a multifactorial event.