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Cellulose fibers were modified via aqueous silane-graphene oxide (GO) coordination by flash drying and extrusion dispersion process. The adsorption of GO reduced the polarity of the cellulose fiber surface and attenuated the agglomeration effect between the cellulose fibers, thus facilitating the dispersion of fibers in the rubber matrix. Adding aqueous 3-aminopropylsilane oligomer (8150) incorporated active sites on the surface of cellulose fibers, thereby improving the interfacial binding properties of cellulose nano fibers (CNFs) and natural rubber (NR). After blending the modified CNFs with NR latex, high-temperature flocculation was performed using an atomised flash device. Finally, CNF/NR was pre-dispersed through a twin-screw extruder, after which a CNF/NR masterbatch with excellent performance was prepared. Experimental results revealed that composites prepared using GO-8150 via the flash drying-twin-screw dispersion process exhibited excellent dispersion characteristics, processing properties, mechanical properties, rolling resistance, wear resistance, and heat generation properties. Compared with traditional dry mixing, the composites prepared by flash drying-twin-screw dispersion process showed a 16.95% increase in tensile strength, 16.07% increase in 300% constant elongation, 19.01% reduction in abrasion consumption, 42.26% reduction in rolling resistance, and a reduction in the Payne effect. This study offers an efficient and environmentally friendly method for the high-value utilization of natural fibers and the preparation of NR composites with excellent properties, while providing a green and nonpolluting modification process with no acidic liquid discharge. Highlights * GO-8150 reduces the polarity of the fibers and promotes dispersion. * The flash extrusion dispersion process achieves green flocculation. * 42% lower rolling resistance for rubber composites. KEYWORDS aqueous silane, cellulose fiber, graphene oxide, natural rubber, rolling resistance, 1 1 INTRODUCTION Carbon black, silica, wollastonite, and calcium carbonate are commonly used as fillers in the rubber industry. In recent years, efforts have been made to limit the use [...]

Purpose: To measure zirconia-to-zirconia microtensile bond strength (µTBS) using composite cements with and without primer. Materials and Methods: Two Initial Zirconia UHT (GC) sticks (1.8x1.8x5.0 mm) were bonded using four cements with and without their respective manufacturer's primer/adhesive (G-CEM ONE [GOne] and G-Multi Primer, GC; Panavia V5 [Pv5]), and Panavia SA Cement Universal [PSAu], and Clearfil Ceramic Plus, Kuraray Noritake; RelyX Universal (RXu) and Scotchbond Universal Plus [SBUp], 3M Oral Care). Specimens were trimmed to an hour-glass shaped specimen whose isthmus is circular in cross-section. After 1-week water storage, the specimens were either tested immediately (1-week µTBS) or first subjected to 50,000 thermocycles (50kTC-aged µTBS). The fracture mode was categorized as either adhesive interfacial failure, cohesive failure in composite cement, or mixed failure, followed by SEM fracture analysis of selected specimens. Data were analyzed using linear mixed-effects statistics (α = 0.05; variables: composite cement, primer/adhesive application, aging). Results: The statistical analysis revealed no significant differences with aging (p = 0.3662). No significant difference in µTBS with/without primer and aging was recorded for GOne and PSAu. A significantly higher µTBS was recorded for Pv5 and RXu when applied with their respective primer/adhesive. Comparing the four composite cements when they were applied in the manner that resulted in their best performance, a significant difference in 50kTC-aged µTBS was found for PSAu compared to Pv5 and RXu. A significant decrease in µTBS upon 50kTC aging was only recorded for RXu in combination with SBUp. Conclusion: Adequate bonding to zirconia requires the functional monomer 10-MDP either contained in the composite cement, in which case a separate 10-MDP primer is no longer needed, or in the separately applied primer/adhesive. [ABSTRACT FROM AUTHOR]

Highlights Blends of natural rubber (NR)/chlorobutyl rubber (CIIR) (50/50), along with their nanocomposites containing varying amounts of graphene nanoparticles (GNPs) with and without silane, were prepared using different feeding sequences and mixers. The results indicated that when GNP was first mixed with NR before adding CIIR, the highest GNP content was found in NR; the oxygen permeability and diffusion coefficient decreased significantly by 37% and 55%, respectively. Conversely, when graphene was initially added to CIIR, it was distributed in both rubbers and at the interface, enhancing phase interaction and achieving a finer morphology. This sample exhibited the greatest improvement in mechanical properties due to specific localization of GNP and increased crosslink density. Using an internal mixer instead of a two‐roll mill improved graphene dispersion, reduced curing time, and enhanced mechanical properties. Although the presence of silane reduced graphene dispersion, it improved mechanical and barrier properties due to increased crosslink density. Oxygen permeability was reduced by up to 36% at 3 phr of GNP content with silane. This research proves that the mixing order and the type of mixing equipment are crucial in determining the final performance of rubber composites, as they significantly influence the dispersion and localization of fillers. NR/CIIR/GNP nanocomposites were prepared by different methods and evaluated. Adding NR/GNP to CIIR led to more presence of GNP in NR and lower permeability. By adding CIIR/GNP to NR, GNP were placed more at interface, modulus improved. Mixing in an internal mixer improved GNP dispersion compared to a two‐roll mill. Silane improved mechanical and barrier properties of NR/CIIR/GNP nanocomposite. [ABSTRACT FROM AUTHOR]

Given the substantial emissions of CO2 into the atmosphere, there is a critical need for effective CO2 adsorbents at scale, ideally derived from abundant and sustainable natural resources. In this work, microcrystalline cellulose derived from cotton is used to fabricate cellulose aerogel as porous support via a NaOH/urea‐based dissolution and regeneration process, followed by surface modification with a series of amino silane coupling agents to produce aminated cellulose aerogel as CO2 adsorbent. The as‐synthesized optimal adsorbent exhibits a high CO2 sorption capacity of up to 1.5 and 1.3 mmol g−1 at 0 °C and 25 °C at 1 bar, respectively. Notably, in‐depth analysis shows that the adsorbent achieves an impressive capacity of CO2 uptake of 0.29 mmol g−1 at 25 °C at an exceptionally low CO2 pressure of 0.4 mbar, i.e., under ambient CO2 pressure. It implies its potential use as adsorbent both for the traditional point‐source capture and the direct air capture as an emerging negative emission technology. This study underscores the environmentally friendly, cost‐effective, and biosourced attributes of aminated cellulose aerogel as a compelling alternative for carbon capture, contributing to global initiatives combating CO2 emissions and stressing the key role of sustainable materials in tackling this global environmental challenge. [ABSTRACT FROM AUTHOR]

Highlights This study investigates the impact of coupling agent‐modified resistance welding heating elements on the welding strength of carbon fiber‐reinforced polyamide 6 (PA6) thermoplastic composites. Silane coupling agent KH550 and titanate coupling agent UP‐201 were used to modify heating elements made of 304 stainless steel mesh. Optimal modification parameters for KH550‐modified stainless steel mesh (SSM) were determined using orthogonal experiments, resulting in maximum single lap shear strength (LSS) of 17.05 MPa under specific welding conditions. Comparative tests demonstrated the enhancement effect of UP‐201‐modified SSM on LSS. Additionally, two experimental schemes were used to study the synergistic enhancement effect of KH550 and UP‐201 on the LSS of resistance welded joints. The findings indicate that both coupling agents improve the welding strength, with significant differences in their individual and combined effects. This study explores carbon fiber reinforced Nylon 6, an innovative thermoplastic. Analyzed effects of modified heating elements on joint shear strength. Examined silane and titanate coupling agents' effects on weld joint shear strength. Investigated synergistic effects of silane and titanate agents on weld joint strength. Investigated the synergistic enhancement mechanism of silane and titanate agents. [ABSTRACT FROM AUTHOR]

This study investigates the preparation of natural rubber latex (NRL) composites with varying nanosilica contents of 5, 15, 30, and 45 phr, using both interfacial and conventional mixing techniques. Analysis focused on viscosity, plasticity, morphology, and FTIR spectra to evaluate the impact of these methods on composite properties. The interfacial technique maintained lower viscosity values, indicating better latex stability, and achieved higher silica yields and conversion rates (94 - 99%) at elevated TEOS contents. Plasticity analysis revealed that the interfacial method produced more uniform and stable plasticity values, suggesting improved resistance to oxidation and enhanced mechanical properties. SEM and FTIR analyses confirmed superior dispersion with the interfacial technique, especially at higher silica contents. These findings highlight the efficacy of the interfacial technique in optimizing the properties of NRL composites, making it a promising approach for advanced material applications. [ABSTRACT FROM AUTHOR]

High crystalline quality and flat a‐plane aluminum gallium nitride (AlGaN) films are obtained on Si‐doped AlN templates with a moderate silane (SiH4) flow rate by metal‐organic chemical vapor deposition (MOCVD). The effects of the SiH4 flow rate on the surface morphology, crystalline quality, stress state, and optical property of a‐plane AlN templates and AlGaN films are comprehensively investigated. As the SiH4 flow rate increases from 0 to 7.0 nmol min−1, the full width at half maximum of X‐ray rocking curve values along [0001]/[1–100] directions for the AlGaN films are monotonically reduced to 1124/1143 arcsec. Meanwhile, the surface root mean square roughness value is decreased to 0.88 nm. These achievements are attributed to the suppression of the anisotropy degrees and in‐plane stress of AlN templates. In addition, an excess SiH4 flow rate leads to deteriorated surface morphologies and increased basal plane stacking fault (BPSF) densities for both AlN and AlGaN films. This work suggests that doping AlN layers with an appropriate SiH4 flow rate is a promising route to obtain high‐quality a‐plane AlGaN films for efficient nonpolar deep ultraviolet (DUV) devices. [ABSTRACT FROM AUTHOR]

A metal‐free one‐pot synthesis route has been documented for the production of 1,1‐unsymmetrical di‐aryl alkanes via reductive Friedel−Crafts alkylation of arenes with carbonyl compounds in 1,1,1,3,3,3,–hexafluoroisopropanol (HFIP) solvent. This approach exhibits a wide substrate scope accommodating diverse functionalities. The transformation of carbonyl compounds into alkylated products is facilitated by dimethylchlorosilane (Me2SiClH) reduction, succeeded via nucleophilic attack of arenes. The established protocol demonstrates a promising strategy for converting indoline‐2,3‐dione into α‐aryl oxindoles with high yields. The reaction involves reduction with Me2SiClH, followed by the attack of arenes in the presence of a TfOH catalyst. The devised protocol offers scalability and remarkable tolerance towards various functional groups. Control experiments provide insights into the reaction mechanism, highlighting the crucial roles of HFIP and Me2SiClH. Furthermore, the method is adaptable for late‐stage functionalization of numerous natural products and pharmaceuticals such as Sesamol, Thymol, Paracetamol, Menthol, and Nerol. Significantly, the technique has proven effective in efficiently synthesising the anticoagulant drug Phenprocoumon and the rodent control agent Coumatetralyl. [ABSTRACT FROM AUTHOR]

Extracting microplastics from natural sources is challenging, especially microplastics with sizes smaller than 100 μm. The flotation method is the most common microplastic extraction, but it struggles with fine particles due to the difficulty in collecting floating plastic particles from the liquid during the separation process. This study proposes a new floating media, tetraethyl orthosilicate (TEOS), that could separate microplastics using its hydrophobic-oleophilic properties. Most interestingly, TEOS transformed from a liquid state to a solid state (gel) by hydrolysis and condensation reactions, thus safely capturing the separated microplastic particles after flotation and mitigating particle loss from scooping since its gel acted as a particle holder. The average recovery rates obtained were in the range of 95–100% for polyethylene terephthalate, polyethylene, polypropylene, polyvinyl chloride, polystyrene, polytetrafluoroethylene, and aged tyre rubber. The recovery rates were slightly reduced for finer particles (sizes down to 40 μm) at 82–98%. TEOS-based extraction provided a higher recovery rate for non-polar plastics than for polar or hydrophilic plastics. The separated microplastics maintained their characteristics for polymer identification, as proven by spectroscopic and thermal analysis techniques. Therefore, TEOS-based extraction could be a new approach to microplastic extraction, especially for preventing fine particle loss. [ABSTRACT FROM AUTHOR]

One of the most important advantages and applications of coated nanoparticles in biological applications is their use in isolating different types of cells to diagnose and treat all types of diseases. Therefore, in this research work, the possibility of isolation and enrichment of B cells using magnetic iron oxide nanoparticles have been investigated. In this regard, magnetic nanoparticles are first coated with (3‐aminopropyl)triethoxysilane to make them hydrophilic and prevent their clumping, then reacted with and rendered biocompatible by FITC anti‐human CD20 antibody. These nanoparticles containing antibodies have been used to isolate B cells from the lymphatic cells. Transmission electron microscopy (TEM) and vibrating‐sample magnetometry (VSM) tests were used to check the magnetic properties and coating of nanoparticles. The flow cytometry and fluorescent microscopy tests are used to check antibody binding to nanoparticles. Moreover, flow cytometry tests were used to check the extent of cell separation. Results show that nanoparticles reacted with 450 μL of antibody (T450) performed better than other nanoparticles in isolating B cells. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the shear bond strength (SBS) when bonding a universal resin cement to a disilicate glass‐ceramic using different adhesive protocols. Sixty specimens were etched with 10% hydrofluoric acid (HF) for 20 s and assigned to one of four treatment protocols (n = 15): The Positive control protocol comprised use of a universal adhesive system + adhesive resin cement; the Test1 protocol comprised use of a new universal adhesive system + universal resin cement; the Test2 protocol comprised use of a silane coupling agent + universal resin cement; and the use of a universal resin cement without adhesive and silane served as the Negative control. One of the two resin cement cylinders built on each specimen in each group was used to test for 24‐h SBS, while the other was thermocycled and then tested for SBS. Data were submitted to two‐way ANOVA, Tukey's test, and Weibull analysis. The negative control (24 h) showed the lowest SBS mean value. The Test2 protocol resulted in the highest SBS mean value after thermocycling. Adhesive and mixed failures were prevalent in all groups. No statistical difference in m values was observed among the groups at 24 h. After thermocycling, the two Test protocols showed the highest m values. The m values were significantly lower after thermocycling than at 24 h for all groups. After thermal aging, The Test2 protocol resulted in a statistically significantly higher SBS mean value after thermal aging than seen for the other groups. [ABSTRACT FROM AUTHOR]

The changing demands in terms of the compactness and performance of electronic devices increase the role of thermal management within this application field. Because polymers and especially thermosets have a low thermal conductivity, filler systems have to be used to improve their performance and make thermosets suitable for applications. So far, several factors influencing thermal conductivity have been defined; however, the combined investigation of mechanical properties as another important value in terms of applications has not been realized. Therefore, this paper analyzes thermal conductivity based on the orientation of fillers and a contact path as well as mechanical properties in different material systems. In addition to the matrix material, the filler type and grade and the geometry and size were varied. It was shown that boron nitride provides the best values in terms of thermal conductivity after orientation along the flow path is realized. An aluminum silicate was defined as the best filler system in terms of mechanical properties. However, the boron nitride was found to reveal the greatest potential in terms of applications, since the mechanical properties are likely to be increased by the usage of finishing additives such as silane. [ABSTRACT FROM AUTHOR]

Highlights In the present study, the basalt fibers (BFs) were treated with hybrid sizings consisting silane coupling agent (3‐Glycidoxypropyl)trimethoxysilane, and silicon dioxide nanoparticles (SNPs). Using acetone washing and heat treatment, the commercial sizing previously on the BFs was removed. Next, the fibers were dip‐coated, and silanes condensed on the surface of the fibers. Fiber samples were characterized using thermogravimetric analysis (TGA), atomic force microscopy (AFM), X‐ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). The test findings demonstrate that acetone extraction was an effective way to remove sizings. The AFM analysis and SEM micrographs demonstrate that SNP and silane particles were dispersed uniformly across the fiber surface. The single fiber tensile testing results indicated that the deposition of hybrid sizings enhanced the fibers strength. Because of the better adhesion between the fiber and epoxy, the hybrid sizings also improved the flexural strength by 22.28% and the interlaminar shear strength by 20.75%. Hybrid sizings (silanes and nano‐particles) on the basalt fiber surface. Characterization of the sizings and understanding of surface morphology. Hybrid sizings resulted in better tensile strength. Failure mechanisms of the fibers were observed using fractography. The effect of hybrid sizing on ILSS and flexural properties was observed. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the effect of silane treatment of a resin-coated resin-based composite (RBC) base material on its microtensile bond strength (μTBS) to a computer aided-design/computer-aided manufacturing (CAD/CAM) ceramic restorative material. RBC blocks (4 mm × 7 mm × 10 mm) were prepared, and the adherend surfaces were prepared as follows: no resin coating + no silane treatment (Group I), no resin coating + silane treatment (Group II), resin coating only (Group III), and resin coating + silane treatment (Group IV). The resin coating was applied with Clearfil SE Bond and flowable RBC to the adherend surface. Each treated sample was bonded to a ceramic block using Panavia V5. After storage in 37 °C water for 1 week, microspecimens were fabricated, and the μTBS was tested. The failure mode of each specimen was determined using stereomicroscopy and scanning electron microscopy. The µTBS of Group II (20.2 ± 4.0 MPa) was not significantly different from that of Group I (17.6 ± 5.9 MPa) (p > 0.05), and the µTBS of Group I was significantly smaller than that of Group III (21.3 ± 7.2 MPa) (p < 0.05). The µTBS of Group IV (24.9 ± 3.8 MPa) was significantly greater than that of Group III (p < 0.05). Our findings indicate that silane treatment of the resin-coated surface can enhance the µTBS. Silane treatment of RBC base material was not effective when prepared without resin coating. [ABSTRACT FROM AUTHOR]

This study focuses on developing an innovative packaging material for fresh strawberries composed of electrospun poly(ε‐caprolactone) (PCL)/poly(vinylpyrrolidone) (PVP) fibers decorated by pure graphene oxide (GO) and functionalized GOs with silane agents using the electrospinning technique. Initially, synthesized GO was first functionalized by silane agents, and followed by the fabrication of electrospun PCL/PVP fibers incorporating both pure GO and functionalized GOs. The surface morphological analyses revealed the uniformity, smoothness, and beadless in the fabricated fibers. The average fiber diameter of the PCL/PVP/0.5A‐GO fibers was found as 3244 ± 56 nm. Electrospun PCL/PVP/0.5A‐GO and PCL/PVP/0.5G‐GO fibers exhibited increased water absorption ratios over 20 days. The incorporation of GO into the polymer matrix, along with an increase in GO concentration, enhanced the tensile strength of the fibers, found as 5.149 ± 0.032 kPa. In preservation tests on fresh strawberries, PCL/PVP/0.5A‐GO fibers demonstrated superior freshness compared with unpacked strawberries and other variants. The study also highlighted the inhibitory effects of fibers decorated with 0.5% APTES‐GO, showing the highest inhibition zone. In summary, fibers incorporating 0.5% A‐GO effectively extended the shelf‐life of fresh strawberries, making them a promising packaging material for perishable goods. [ABSTRACT FROM AUTHOR]

The quantity of silane chemically bonded to the organoclay's surface significantly influences its dispersion within the polymer matrix, as well as the interfacial interaction. This research presents a groundbreaking method for enhancing the surface properties of montmorillonite (Mt) through the use of γ‐(methacryloxy) propyl trimethoxy silane (KH570) coupled with acid treatment, leading to increased grafting efficiency. Confirmed by FT‐IR, TGA, and XRD, the process effectively bonds organo‐silanes to Mt and achieves a high grafting level of 1.59 mequiv/g. Utilizing a latex compounding method, Mt/rubber nanocomposites are synthesized with thoroughly modified clay for peak performance. Dispersion and interfacial properties are evaluated through XRD, TEM, AFM, and DMTA. The findings reveal that the well‐modified Mt is an exceptional filler, ensuring a high level of dispersion and robust interaction with the rubber matrix. This synergy translates to a marked improvement in the mechanical properties of the composite, with notable enhancements observed in both tensile strength and elongation at break of 9.7 MPa and 1141%, respectively. This innovative approach to the graft modification of clays presents a potent method, offering the potential for the industrial‐scale manufacture of high‐performance clay‐based composites. Highlights: A processing method for preparing high grafting clay with a silane coupling agent.Functionalized clay presents better nano‐dispersion in the polymeric matrix.Strong covalent interfacial interaction is constructed between clay and rubber.Tensile Strength and elongation at break of the composites are obliviously improved. [ABSTRACT FROM AUTHOR]

We disclose herein a triflic acid and silane‐promoted reductive deoxygenative transformation of ketoacid/esters for the divergent synthesis of different‐sized lactones, which hold substantial significance in pharmaceutical and natural product chemistry. Owing to the simple reaction conditions and setup, this protocol features broad substrate generality, scalability, and good functional group tolerance, including late‐stage functionalization of pharmaceutical compounds and natural products. The control experiments and detailed NMR study provide insight into the reaction mechanism. [ABSTRACT FROM AUTHOR]

When the lubricating oil flowing between the contact surfaces contains simulated wear particles, it is considered that there is a high possibility for the particles to enter between the contact surfaces if the particles are present on the disk side in a friction test between a fixed ball and a rotating disk. For particles with a diameter of 0.8 µm, it has been previously shown that the entrainment frequency changes with the outside oil film thickness, but the effect of the disk material on the amount of particle deposition and the visualization of particle movement direction due to vortices generated between the contact surfaces had not been performed. In this study, by using SiO2 disks and sapphire disks with different Hamaker constants, the effect on the amount of particle deposition in front of the contact surfaces was experimentally clarified by changing the van der Waals forces acting between the particles and the disks. Additionally, assuming that vortices generated in the oil film between the contact surfaces move the particles to the disk surface side, the flow direction of the lubricating oil was visualized using Navier-Stokes simulation. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the in vitro influence of prior silane application on the microshear bond strength (μSBS) of Scotchbond Universal Plus to glass ceramic. Materials and Methods: Thirty blocks of lithium disilicate ceramic were etched with hydrofluoric acid for 20 s and distributed into Group 1 (no silane and no adhesive), Group 2 (adhesive), Group 3 (silane + adhesive). Three cylinders of resin cement were made on each ceramic block. Five blocks (n = 15 cylinders) were subjected to the μSBS test after 24 h, and the other five blocks (n = 15 cylinders) were tested after 6 months of water storage. Results: According to two‐way ANOVA, followed by Tukey's test, the means of μSBS (MPa), denoted by different letters, show significant differences (p < 0.05): after 24 h—Group 1 (31.7)B, Group 2 (43.3)A, and Group 3 (31.3)B; after 6 months—Group 1 (14.8)B, Group 2 (33.6)A, and Group 3 (30.3)A. After 6 months of storage, there was a significant decrease in μSBS for Groups 1 and 2, along with an increase in adhesive failures across all groups. Conclusions: Prior application of silane did not increase the μSBS between Scotchbond Universal Plus and ceramic, and there was degradation at the bond interface over time. Clinical Significance: Prior application of a silane agent is not necessary when using Scotchbond Universal Plus for bonding to glass ceramics. Regardless of the prior application of silane, there is degradation at the bond interface over time. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the repair bond strength of composite resin following three different surface treatments (bur-grinding, silanization, and Er,Cr:YSGG laser irradiation) using various universal adhesives. A total of 160 resin composite specimens, produced in cylindrical form (6 × 2 mm) with a nanohybrid composite resin within metal molds, were subjected to 5000 cycles of aging in a thermocycler. The aged samples were categorized into four groups based on surface treatments: control, bur, silane, and Er,Cr:YSGG laser. Following surface treatments, the specimens underwent repair using the same resin composite and four different adhesive systems: Tokuyama Universal Bond (TUB), Prime Bond Universal (PBU), Gluma Bond Universal (GBU), and Clearfil SE Bond (CSB). Subsequently, the specimens were subjected to shear forces, and statistical analysis was performed using two-way ANOVA and Tukey tests (p < 0.05). The failure modes were examined using a stereomicroscope, and the surface topography of the roughened resin composite was assessed through scanning electron microscopy (SEM). Results indicated that silane + GBU exhibited the highest shear bond strength (SBS) (15.61 MPa) while control + TUB showed the lowest SBS (7.63 MPa). Silane demonstrated significantly higher SBS values (p ≤ 0.05), with no significant difference observed between bur and laser methods (p = 0.998). It is recommended to include an additional silanization step before applying universal adhesive, as it effectively enhances the bond strength of the repaired composite. [ABSTRACT FROM AUTHOR]

In this study, we analyze metal–insulator–metal (MIM) capacitors with different thicknesses of SixNy film (650 Å, 500 Å, and 400 Å) and varying levels of film quality to improve their capacitance density. SixNy thicknesses of 650 Å, 500 Å, and 400 Å are used with four different conditions, designated as MIM (N content 1.49), NEWMIM (N content 28.1), DAMANIT (N content 1.43), and NIT (N content 0.30). We divide the C–V characteristics into two categories: voltage coefficient of capacitance (VCC) and temperature coefficient of capacitance (TCC). There was an overall increase in the VCC as the thickness of the SixNy film decreased, with some variation depending on the condition. However, the TCC did not vary significantly with thickness, only with condition. At the same thickness, the NIT condition yielded the highest capacitance density, while the MIM condition showed the lowest capacitance density. This difference was due to the actual thickness of the film and the variation in its k-value depending on the condition. The most influential factor for capacitance uniformity was the thickness uniformity of the SixNy film. [ABSTRACT FROM AUTHOR]

Titanium and its alloys are commonly used in dentistry for implants due to their strength, lightweight nature, durability, corrosion resistance, and biocompatibility. These implants can osseointegrate after surface treatments such as SLA, plasma-spray, and nanotubes, providing a stable foundation for prostheses. However, Candida albicans, an opportunistic fungal pathogen, can threaten the success of titanium dental implants, causing oral infections in vulnerable individuals. A dual novel silane blend of 3-acryloxypropyltrimethoxysilane (ACPS) and bis-1,2-(triethoxysilyl)ethane (BTSE) has been shown to improve the shear bond strength in resin cement bonds with titanium and ceramics. This study evaluated the effects of Candida albicans colonization on blended silane-coated SLA-Ti surfaces compared to non-coated SLA-Ti (positive control) and flat titanium (negative control). Candida albicans biofilms were cultured on all surfaces, and it was found that silane-coated SLA-Ti had significantly lower CFU counts than non-coated SLA-Ti. However, no significant differences were observed in the RT-PCR results. In conclusion, a combination of 1.0 vol% ACPS and 0.3 vol% BTSE shows promise as a silane coupling agent with potential antifungal properties for inhibiting Candida albicans proliferation. [ABSTRACT FROM AUTHOR]

Highlights This study assesses the effectiveness of a specially developed surface‐modified carbon black, both on its own and in combination with nano‐silica, as a hybrid filler for ethylene–propylene–diene monomer (EPDM) rubber compounds. The modification process, which included treatment with a silane coupling agent, resulted in enhanced curing characteristics. The ∆Torque values for compounds incorporating the modified carbon black exceeded those of other formulations by 25.85%. Scanning electron microscopy (SEM) analysis demonstrated improved filler dispersion and better compatibility between rubber and filler due to the surface modification. The silane‐modified carbon black showed considerable enhancements in mechanical properties, particularly in tear resistance, with increases in tensile and tear strength of 22.46% and 34.86%, respectively, following surface treatment. Dynamic mechanical analysis (DMA) indicated the influence of both surface modification and filler type, revealing that the combination of modified carbon black and nano‐silica achieved a reduction in rolling resistance of 20.41% and enhanced ice and wet grip performance by 7.95%. Additionally, modified carbon black displayed varying effects on the glass transition temperature. Thermal gravimetric analysis (TGA) confirmed that the thermal stability of the compounds was consistent, while solvent resistance improved with surface modification, as shown by swelling ratios. Thermodynamic analysis indicated that the surface modification of carbon black positively influences the elasticity and chain mobility of the rubber compounds studied. In conclusion, the careful selection and optimization of filler materials and their modifications are essential for customizing the properties of rubber compounds to satisfy specific performance criteria and applications. Promising EPDM compounds were prepared with Silane‐Modified CB and Nano‐Silica. Silane‐modified CB effectively improved the curing properties of the EPDM compound. The ΔTorque and cross‐link density of modified CB/EPDM show the highest value. Modified CB/Nano‐Silica/EPDM exhibited significant improvement in tear strength. Modified CB/Nano‐silica/EPDM have lower rolling resistance and higher wet grip. [ABSTRACT FROM AUTHOR]

This work aims to develop environmentally friendly silane coating reinforced with a hybrid pigment to protect mild steel against corrosion in a saline environment. Fourier-transform infrared (FT-IR) spectroscopy, contact angle (CA) measurement, field emission scanning electron microscopy (FE-SEM), and energy dispersive spectroscopy (EDS) were used to study the coating structure and its protective mechanisms. The presence of hybrid pigment led to the conversion of more Si–OH groups into Si–O–Si groups during condensation process increasing the cross-linking density of silane; the enhanced cross-linking yields the coating with lower defects and stronger adhesion to substrate and so improved barrier and anti-corrosion properties. The EIS test showed that the charge transfer resistance (R ct) for the sample coated with hybrid sol-gel silane increases up to 40 % for all immersion times after the incorporation of the hybrid pigment into the coating matrix. The polarization test showed that the corrosion current density (i corr) value decreases from 1.40 to 0.56 μA/cm2 after 120 h of exposure to the saline solution when the hybrid pigment is added to the coating matrix. These results demonstrate the inhibitive action of the hybrid pigment enhancing the protective performance of the sol-gel silane coating. [ABSTRACT FROM AUTHOR]

This study investigated the effects of different surface treatments and a silane-containing adhesive on the repair bond strength between fresh and aged resin composites. A total of 140 composite specimens were prepared and aged for 24 h or 4 months. Each group was subdivided into seven subgroups (n = 10) depending on the surface treatment (no surface treatment (NT), sandblasting (SAND), or Sof-lex coarse disc (DISC)) in combination with the use of the silane-containing adhesive ScotchBond Universal Plus (SBU) or an adhesive without silane Prime&Bond Universal (P&B). The same composite was used for the repair as for the primary specimen. Specimens were dark stored in distilled water at 37 °C for 28 days. Shear bond strength was tested at a crosshead speed of 0.5 mm/min. The Kruskal–Wallis test with Bonferroni's post-hoc adjustment (α = 0.05) and the Mann–Whitney U-test were used for the statistical analysis. The results are shown as the median with the interquartile range. The highest bond strength (MPa) was achieved after 24 h in the DISC+P&B (20.39(16.85–28.83)). In the fresh 24 h group, the SAND+P&B (12.25(8.28–15.05)) and DISC+SBU (18.37(15.16–21.29)) were statistically similar. In the 4-month groups, both adhesives and surface treatments performed similarly. The NT, SAND, and DISC groups without adhesives had the lowest bond strength. In the repair of fresh or aged composite, the silane-containing adhesive SBU was not superior to the adhesive without the silane (P&B). [ABSTRACT FROM AUTHOR]

Bioinspiration offers alternative solutions to overcome the inherent drawbacks of glass, such as low fracture toughness, strength, and impact resistance. Synthetic composites inspired by natural materials, such as nacre, have been recently introduced as an alternative to glasses. However, these have all suffered from trade‐offs between rigidity, optical clarity, fabrication scalability, and complexity. Here, two wave‐based fabrication techniques are presented to create a nacreous structure from glass flakes and polymethyl methacrylate. The glass's surface energy is controlled by adjusting the silane coverage on the glass surface, enabling high levels of structural compactness, mechanical properties, and optical clarity. The scalable glass composite, with a ≈60% glass volume fraction, possesses strength, fracture toughness, and impact resistance values, outperforming annealed glass by 4300%, 350%, and 400%, respectively. It also has a haze level of ≈18%, almost 60% less than that of the similar centrifuged‐based glass composite. This composite is proposed as a potential glass alternative in diverse applications. [ABSTRACT FROM AUTHOR]

Elemental sulfur has shown to be a promising alternative feedstock for development of novel polymeric materials with high sulfur content. However, the utilization of inverse vulcanized polymers is restricted by the limitation of functional comonomers suitable for an inverse vulcanization. Control over properties and structure of inverse vulcanized polymers still poses a challenge to current research due to the dynamic nature of sulfur‐sulfur bonds and high temperature of inverse vulcanization reactions. In here, we report for the first time the inverse vulcanization of norbornenyl pentafluorophenyl ester (NB‐PFPE), allowing for post‐modification of inverse vulcanized polymers via amidation of reactive PFP esters to yield high sulfur content polymers under mild conditions. Amidation of the precursor material with three functional primary amines (α‐amino‐ω‐methoxy polyethylene glycol, aminopropyl trimethoxy silane, allylamine) was investigated. The resulting materials were applicable as sulfur containing poly(ethylene glycol) nanoparticles in aqueous environment. Cross‐linked mercury adsorbents, sulfur surface coatings, and high‐sulfur content networks with predictable thermal properties were achievable using aminopropyl trimethoxy silane and allylamine for post‐polymerization modification, respectively. With the broad range of different amines available and applicable for post‐polymerization modification, the versatility of poly(sulfur‐random‐NB‐PFPE) as a platform precursor polymer for novel specialized sulfur containing materials was showcased. [ABSTRACT FROM AUTHOR]

The erosion phenomena of the natural stone in cultural heritage are induced by various sources. Consequently, the development of multifunctional protective materials that combine two or more useful properties is an effective strategy in addressing the synergistic effects of various erosion mechanisms. A multifunctional coating, consisting of a silane-based precursor and zinc oxide (ZnO) nanoparticles (NPs), is produced and tested for the protection of limestone. The hybrid coating combines the following three properties: superhydrophobicity, including water-repellency, photocatalytic self-cleaning and biocidal activity. The relative concentration of the NPs (0.8% w/w), used for the suggested composite coating, is carefully selected according to wetting studies, colourimetric measurements and durability (tape peeling) tests. The non-wetting state is evidenced on the surface of the composite coating by the large contact angle of water drops (≈153°) and the small contact angle hysteresis (≈5°), which gives rise to a physical self-cleaning scenario (lotus effect). The photocatalytic chemical self-cleaning is shown with the removal of methylene blue, induced by UV-A radiation. Moreover, it is shown that the suggested coating hinders the incubation of E. coli and S. aureus, as the inhibitions are 94.8 and 99.9%, respectively. Finally, preliminary studies reveal the chemical stability of the suggested coating. [ABSTRACT FROM AUTHOR]

Polymer composites are widely used in various fields of production and life, and the study of preparing environmentally friendly and flame retardant clay/polymer composites has gradually become a global research hotspot. But how to efficiently surface modify clay and apply it to the field of flame retardant polymers is still a potential challenge. One of the most commonly used surface modification methods is the modification of clay with silane coupling agents. The hydrolysable groups of the silane coupling agent first hydrolyze to generate hydroxyl groups. These hydroxyl groups then undergo a condensation reaction with the hydroxyl groups on the surface of the clay, allowing for organic functional groups to be grafted onto the clay surface. The organic functional groups and polymer matrix react to generate chemical bonds so that the composite material's interface is more closely combined. Thus, the dispersion of clay in the organic polymer material and the compatibility of the two is better, which improves the flame retardant effect of the composite material. This paper introduces the classification of a silane coupling agent and the mechanism and process of silane coupling agent-modified clay, outlines the mechanism of silane coupling agent-modified clay flame retardant polymers, reviews the research results on flame retardant polymers of various clays after surface treatment with silane coupling agents in recent years, and highlights the synergistic flame retardant effect of clay and flame retardant organized by silane coupling agents. Finally, it is found that the current research in the field of silane coupling agent-modified clay in flame retardants is focused on the modification of montmorillonite, sepiolite, attapulgite, and kaolinite by KH-550, KH-560, and KH-570, and the development trends in this field are also prospected. [ABSTRACT FROM AUTHOR]

Dental resin composites are widely used in clinical settings but often face longevity issues due to the development and accumulation of microcracks, which eventually lead to larger cracks and restoration failure. The incorporation of microcapsules into these resins has been explored to introduce self-healing capability, potentially extending the lifespan of the restorations. This study aims to enhance the performance of self-healing dental resins by optimizing the microcapsules–resin matrix physicochemical interactions. Poly(urea–formaldehyde) (PUF) microcapsules were reinforced with melamine and subsequently subjected to surface functionalization with 3-aminopropyltriethoxysilane (APTES) and (3-mercaptopropyl)trimethoxysilane (MPTMS). Additionally, microcapsules were functionalized with a bilayer approach, incorporating tetraethyl orthosilicate (TEOS) with either APTES or MPTMS. X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA) confirmed an increased Si:C ratio from 0.006 to 0.165. The functionalization process did not adversely affect the structure of the microcapsules or their healing agent volume. Compared to PUF controls, the functionalized microcapsules demonstrated enhanced healing efficiency, with TEOS/MPTMS-functionalized microcapsules showing the highest performance, showing a toughness recovery of up to 35%. This work introduces a novel approach to functionalization of microcapsules by employing advanced silanizing agents such as APTES and MPTMS, and pioneering bilayer functionalization protocols through their combination with TEOS. [ABSTRACT FROM AUTHOR]

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The ideal composite electrolyte for the pursued safe and high‐energy‐density lithium metal batteries (LMBs) is expected to demonstrate peculiarity of superior bulk conductivity, low interfacial resistances, and good compatibility against both Li‐metal anode and high‐voltage cathode. There is no composite electrolyte to synchronously meet all these requirements yet, and the battery performance is inhibited by the absence of effective electrolyte design. Here we report a unique "concentrated ionogel‐in‐ceramic" silanization composite electrolyte (SCE) and validate an electrolyte design strategy based on the coupling of high‐content silane‐conditioning garnet and concentrated ionogel that builds well‐percolated Li+ transport pathways and tackles the interface issues to respond all the aforementioned requirements. It is revealed that the silane conditioning enables the uniform dispersion of garnet nanoparticles at high content (70 wt%) and forms mixed‐lithiophobic‐conductive LiF‐Li3N solid electrolyte interphase. Notably, the yielding SCE delivers an ultrahigh ionic conductivity of 1.76 × 10−3 S cm−1 at 25 °C, an extremely low Li‐metal/electrolyte interfacial area‐specific resistance of 13 Ω cm2, and a distinctly excellent long‐term 1200 cycling without any capacity decay in 4.3 V Li||LiNi0.5Co0.2Mn0.3O2 (NCM523) quasi‐solid‐state LMB. This composite electrolyte design strategy can be extended to other quasi−/solid‐state LMBs. [ABSTRACT FROM AUTHOR]

The present study investigated for the first time the characteristic length scale and chemical dynamics of steady and quasi-steady detonation waves propagating in silane-nitrous oxide-nitrogen mixtures, which are widely used in the semi-conductor industry and can be a promising additive for propulsion application. The conditions investigated cover the following ranges: equivalence ratio $\phi $ ϕ = 0.5–5; initial pressure ${P_1}$ P 1 = 10–1000 kPa; nitrogen mole fraction ${X_{{{\rm{N}}_2}}}$ X N 2 = 0–0.8; initial temperature ${T_1}$ T 1 = 300 K. The energy released by the formation of SiO(s) and SiO2(s) was taken into account whereas the phase change from gas to liquid/solid was neglected. It was found that detonation in these silane-based mixtures is characterized by unusually large Mach numbers which result in up to 128.5 times pressure jump across the leading shock, and few micrometer-long induction zone length. For steady planar waves, the shortest induction distances were identified in the range $\phi $ ϕ = 2–4, while for curved detonations, the most resilient wave to curvature-induced losses was identified at $\phi $ ϕ around 1.5 for undiluted mixtures. Such phenomena are the results of the enhanced formation of SiO(s) under fuel-rich conditions, which also contributes to stabilizing the detonation wave, though the mixture should still be classified as unstable, according to traditional stability parameters. Detailed thermo-chemical analyses were performed to investigate the chemical dynamics. The study of the heat release per reaction shows the dominant contributions of R65: H+N2O=N2+OH, R207: SiH4(+M)=H2+SiH2(+M), R377: N2O+SiH2=H2SiO+N2, R379: N2O+Si=N2+SiO, and R400: 2SiO = 2SiO(s). The dominant reactions for heat release are not modified by the curvature-induced loss according to sensitivity analyses. [ABSTRACT FROM AUTHOR]

Objectives: To assess the influence of different primer compositions—silane (S), 10-methacryloyloxydecyl dihydrogen phosphate (MDP), and the combination of silane and MDP (S + MDP)—on the bonding performance of MDP-free and MDP-containing resin cements to highly translucent zirconia. Materials and methods: Tribochemical silica-coated zirconia plates were pretreated with one of three experimental primers, S, MDP, or S + MDP, with untreated specimens serving as controls. Subsequently, these plates were bonded to stainless-steel rods using either two MDP-free or two MDP-containing resin cements. Tensile bond strength was measured after 24 h (TC0) and following thermal cycling (4–60 °C for 10,000 cycles; TC10,000). Data were analyzed using a three-way analysis of variance (ANOVA), followed by one-way ANOVA and Tukey-Kramer post hoc tests (α = 0.05). X-ray photoelectron spectroscopy (XPS) assessed the elemental mass concentrations on the zirconia surfaces. Results: For MDP-free resin cements, MDP-treated specimens exhibited significantly greater bond strengths than controls, regardless of the aging conditions. However, a significant reduction in bond strength was observed between TC0 and TC10,000 in most of the MDP-free resin cement groups, except for one S + MDP group. Conversely, for MDP-containing resin cements, the S + MDP group exhibited no statistically significant differences between aging conditions. Notably, XPS analysis detected silicon, zirconium, and aluminum on the zirconia surfaces. Conclusions: No significant difference in tensile bond strength was observed between aging conditions for MDP-containing resin cements bonded to tribochemical silica-coated zirconia primed with S + MDP. Clinical relevance: The combination of MDP-containing primers and resin cements demonstrated superior bonding performance to tribochemical silica-coated zirconia. [ABSTRACT FROM AUTHOR]

Abstract Water is necessary for the alkali aggregate reaction to occur and this study investigates the impact of waterproofing on alkali-aggregate reaction (AAR) in concrete by separating water from alkali reactive aggregates through surface, aggregate, and matrix treatments. Accelerated mortar bar tests (AMBT) are conducted to analyze the expansion caused by alkali aggregates. Furthermore, the suppressive mechanism of waterproofing on AAR is explored using scanning electron microscopy (SEM), while the influence of waterproof concrete aggregate and matrix on pore characteristics and hydration products is assessed using nuclear magnetic resonance (NMR) and X-ray diffraction (XRD). The results demonstrate that surface waterproofing with silane and polyvinyl alcohol (PVA) effectively suppress AAR. Moreover, PVA-coated aggregates significantly enhance the compactness of the interfacial transition zone (ITZ) in concrete. Based on these findings, an improved model considering waterproofness is proposed to quantify the degree of alkali aggregate reaction. These findings offer valuable guidance for controlling AAR.

Highlights The valorization of plant wastes for developing environmentally friendly composites has garnered increasing attention over the past two decades. The management of a significant quantity of Nile rose plant waste presents a mounting challenge, particularly in light of escalating water demand. This study delves into the impact of Nile rose fiber (RF) loading and utilizing Vinyltrimethoxysilane (VTMS) as a coupling agent on the characteristics of a composite comprising RF and natural rubber (NR). The verification of the fiber structure treated with silane (TF) was accomplished via Fourier transform infrared (FTIR) spectroscopy. The crosslinking between the NR matrix and the fibers is promoted by the formation of siloxane (SiOSi) linkages in 1050–1100 cm−1. An extensive evaluation of the impact of RF on the characteristics of NR composite was conducted, encompassing morphological properties, mechanical characteristics, and water absorption resistance. The results of the morphological analysis revealed that the modification of RF with silane enhanced the interfacial adhesion between RF and NR. Furthermore, the tensile strength (TS) of NR increases to values of 7.31 and 8.5 MPa by an improvement of 61% and 88% when 10 and 15 phr of TF are added, respectively. Moreover, rubber composites with silane exhibited superior water resistance to those without it across various filler loadings. Specifically, the composite with 20 phr TF absorbed 7% water, whereas the counterpart with untreated fiber (RF) absorbed 12.5% water. The analysis of swelling validated that the interaction between the RF and NR is significantly impacted by the modification of fiber and its incorporation into the composite, as evidenced by the decreased swelling index values from 367% to 298% observing in composites incorporating TF as opposed to those containing RF. Silane treatment improves the interaction between RF and NR. The TF and NR matrix interacted more and developed an interfacial bonding. The rate of vulcanization is accelerated in the presence of treated RF. TF/NR composites have fewer voids and microcracks, inhibiting water diffusion. 15% TF content optimal for good physical and mechanical properties. [ABSTRACT FROM AUTHOR]

Organic–inorganic composite antibacterial materials based on AgPc/Ag and aminosilane‐modified silicate (Ormosil) were prepared by sol‐gel processes and an in situ reduction method. The physical and chemical properties of AgPc, Pc‐Ormosil and AgPc‐Ormosil/Ag composites were analyzed by SEM, XRD, NMR and XPS spectroscopy. As a result, Ag nanoparticles were bonded and chelated in Pc‐Ormosil matrix. The morphology analysis of SEM showed that the AgNPs in the Pc‐Ormosil matrix were spherical and uniformly distributed, with a size of about 5–10 nm. These NMR and XPS results indicated that the AgNPs were coordinated with Pc (N−Ag−N) and chelated with Ormosil (−CH2NH...Ag) to form a AgPc‐Ormosil/Ag composite. The antibacterial effects of AgPc‐Ormosil/Ag composites on Gram‐negative Pseudomonas aeruginosa and Escherichia coli, and Gram‐positive Staphylococcus aureus and Bacillus subtilis were evaluated by inhibiting ring, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and plate counting. The MIC/MBC values of Pc‐Ormosil, AgPc‐Ormosil/Ag‐2.5, AgPc‐Ormosil/Ag‐5 and AgPc‐Ormosil/Ag‐10 against bacteria were 11.0/>11.0, 1.10/1.10, 0.11/0.11 and 0.011/0.011, respectively, indicating excellent antibacterial properties. [ABSTRACT FROM AUTHOR]

Concrete coatings show significant promise in shielding concrete substrates from corrosion by effectively resisting harmful ions and moisture. Thanks to their practicality, high efficiency, and cost-effectiveness, coatings are considered a potent technique for enhancing the chloride resistance of reinforced concrete structures. Over recent decades, extensive research has concentrated on employing coatings to bolster concrete's ability to withstand chloride penetration. This paper provides a holistic review of the current studies on chloride infiltration in concrete surfaces treated with coating materials, primarily focused on chloride resistance improvement efficiency and chloride transport modeling. Firstly, by comparing the functions of assorted coatings, four inherent protection mechanisms are summarized and elaborated thoroughly. Afterwards, the chloride resistance improvement efficiency of assorted coatings reported in current studies are reviewed and compared in great detail, with a specific focus on inorganic, organic, and organic–inorganic composite coatings. Furthermore, the theoretical research about methodologies for chloride transport behavior prediction is summarized. Finally, this paper outlines the potential research directions in this field and the theoretical, technical, and practical application challenges. This review not only identifies critical areas necessitating further investigation and problem-solving in this domain but also aids in selecting appropriate coating materials and refining corrosion management strategies. [ABSTRACT FROM AUTHOR]

The hemp-reinforced polypropylene composite was produced by the twin-screw extrusion in the presence of polypropylene-graft-maleic anhydride (PP-g-MA) and silane as coupling agents and subsequence by the compression molding. The hemp fiber was obtained by sodium hydroxide treatment prior to the twin-screw extruder. The PP/Hemp composite was analyzed using a universal testing machine, scanning electron microscope, differential scanning calorimetry, X-ray diffraction, and Fourier transform infrared spectroscopy. The mechanical properties of the PP/MA/Hemp demonstrated a better result than that of PP/Si/Hemp in most hemp contents. The SEM images of the PP/MA/Hemp exhibited excellent interfacial bonding in PP/MA/Hemp30 without fiber pullouts. However, the fiber breakage and some fiber pullout with gaps around the fiber of PP/Si/Hemp indicate the poor bonding of the PP matrix. The functional group of the PP/Hemp composite showed the –OH cellulose result peak of the reaction between hemp fibers and polypropylene. [ABSTRACT FROM AUTHOR]

The goal of this work was to develop acrylonitrile–butadiene (NBR) elastomer composites filled with hydroxyapatite (HAP) characterized by improved cure characteristics and resistance to burning. Silane, i.e., (3-aminopropyl)-triethoxysilane, ionic liquid, i.e., 1-decyl-3-methylimidazolium bromide and surfactant, i.e., cetyltrimethylammonium bromide, were used to improve the filler's dispersibility in the elastomer matrix and to reduce the time and temperature of vulcanization. The effects of HAP and dispersants on the cure characteristics, crosslink density and physico–chemical properties of NBR composites were explored. The additives used, especially the ionic liquid and surfactant, effectively improved the dispersion of HAP in the NBR matrix. The amount of HAP and the dispersant used strongly affected the cure characteristics and crosslink density of NBR. The optimal vulcanization time significantly increased with HAP content and was pronouncedly reduced when ionic liquid and surfactant were applied. In addition, ionic liquid and surfactant significantly lowered the onset vulcanization temperature and improved the crosslink density and hardness of the vulcanizates while impairing their elasticity. HAP and dispersants did not significantly affect the damping properties or chemical resistance of NBR vulcanizates. Above all, application of HAP considerably enhanced the resistance of vulcanizates to thermo-oxidative aging and reduced their flammability compared with the unfilled NBR. [ABSTRACT FROM AUTHOR]

This study discusses an approach that gives the Natural Rubber (NR) vulcanizates an elevated hydrophobic character. The method used a chemically treated filler called diatomaceous earth (DE) to deliver the hydrophobic characteristics to NR. DE has a nanoscale roughness. It was chemically treated with hexadecyltrimethoxy silane to obtain low surface energy. The combination of nanoscale roughness and low surface energy gave superhydrophobic properties to DE. A series of treated-DE was made with varying silane percentages to find an optimum silane to DE ratio to get the maximum possible hydrophobicity. The optimum ratio was recorded as 38% w/w, and the treated DE displayed a superhydrophobic water contact angle (WCA) of 152°. The treated-DE was added to the rubber as a filler during the compounding process. The filler was added in varying amounts of 5 phr, 10 phr, 15 phr, and 20 phr to observe the changes in the hydrophobic property. The wettability and morphology of developed vulcanizates were measured using WCA measurements and scanning electron microscope (SEM) analysis, respectively. NR compounded with 20 phr filler exhibited an enhanced WCA of 136°, compared to the WCA of 92° of the NR vulcanizate with no treated-DE, and displayed improved tensile, and tear properties. [ABSTRACT FROM AUTHOR]

This article aims to prepare a nitrogen, silicon, and phosphorus multiple synergistic high-efficiency flame retardant and study its application performance. Firstly, allyl substituted melamine was synthesized by melamine powder and allyl bromide. After copolymerizing it with vinyltrimethoxysilane, a nitrogen-silicon containing melamine copolymer was obtained. Using the equal volume impregnation method, a certain mass of Type I ammonium polyphosphate (I-APP) powder is mixed with an equal volume of nitrogen-silicon containing melamine copolymer solution to prepare nitrogen silicon flame retardant copolymer coated I-APP flame retardant (MAPP). Pre mix polypropylene(PP) with a certain mass fraction of I-APP or MAPP flame retardant, and then perform melt blending, extrusion, and granulation in a twin-screw extruder to prepare PP flame retardant composites. Mechanical and vertical combustion tests were conducted on PP flame-retardant composites. The results showed that when MAPP was added up to 20%, it could reach the V-0 flame retardant level, while pure I-APP, even with 30% addition, remained below the V-0 level and had lower mechanical properties. It can be seen that the compatibility of I-APP coated with nitrogen silicon copolymer is better, and the synergistic flame retardant efficiency among nitrogen, silicon, and phosphorus is higher. [ABSTRACT FROM AUTHOR]

In this work, we investigate additively manufactured composites with populations of coarse and fine glass microspheres that are functionalized using silane coupling agents to explore how and why different functionalization of the fine and coarse fractions leads to vastly different mechanics. Combining strong interfaces on fine particles with weak interfaces on coarse particles leads to enhancements in elongation to break and toughness, whereas combining two types of strong interfaces leads to enhancement in elongation to break and reduction or maintenance of other measured tensile properties. These results can inform future work in tailoring mechanics of highly filled additively manufactured composites. [ABSTRACT FROM AUTHOR]

The use of fillers based on natural resources in composite materials represents a massive potential for biomedical applications. However, up to this date, the use of natural resources for materials reinforcement in dental field is still lacking. Thus, the suitability of using kenaf cellulose nanocrystals as a co-filler treated via silane hybridization was assessed by means of thermal stability and mechanical strength of rice husk nanohybrid dental composite. Kenaf cellulose nanocrystals (CNCs) were surface-modified and treated with silane hybridization at varying ratios of γ-methacryloxypropyltrimethoxysilane and tetraethyl orthosilicate sol–gel (0:1, 1:1, 1:2, and 1:3). Following chemical and thermal analysis, the treated kenaf CNCs were incorporated into the nanohybrid rice husk dental composites (K00, K01, K11, K12, and K13). The prepared samples were sent for flexural and compressive strength tests. The Fourier transform infrared spectroscopy spectra detected the formation of chemical bonds between kenaf CNCs and γ-MPS/TEOS hybridized silane. For thermogravimetric analysis, the untreated kenaf CNCs recorded the highest decomposition temperature compared to silane-treated kenaf CNCs. The K13 composite (silane-treated kenaf CNCs with γ-MPS:TEOS of 1:3) demonstrated an enhanced flexural strength of 31% and compressive strength of 38% compared to the non-fiber-reinforced composite. In conclusion, optimal surface treatment hybridization of kenaf CNCs with silane at γ-MPS:TEOS of 1:3 significantly enhanced the mechanical properties of the rice husk nanohybrid dental composite and insignificantly influenced the thermal stability of the composite. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effect of additional silane treatment on the immediate and aged microtensile bond strength (µTBS) between resin-based composite (RBC) post-and-core build-up material and an RBC CAD/CAM block. Twelve sample blocks (12 mm × 14 mm × 9 mm) were prepared using RBC post-and-core build-up material and were divided into six groups: Kerr Silane Primer (Sil) + OptiBond eXTRa Universal adhesive (EXA); OptiBond eXTRa Universal Primer (EXP) + EXA; Sil + OptiBond Universal (OBU); OBU; Sil + OptiBond Solo Plus (OSP); and OSP. Each treated sample was luted to a CAD/CAM block using an NX3 Nexus Third-Generation instrument. After storage in 37 °C water for 1 week, microspecimens were fabricated, and μTBS was tested immediately or after further immersion in water at 37 °C for 6 months. The failure mode of each specimen was determined using stereomicroscopy and scanning electron microscopy. For the immediate groups, no significant difference in µTBS was found between specimens with or without silane treatment for each adhesive (p > 0.05). For the aged groups, silane treatment significantly decreased µTBS for OptiBond eXTRa Universal (p < 0.05). Our findings indicate that additional silane treatment prior to the application of adhesive did not enhance µTBS. [ABSTRACT FROM AUTHOR]

Waterproof and breathable fibrous membrane is a new type of polymer functional material widely used in outdoor protection, sports equipment, industrial production, and other fields. To impart waterproof ability and breathability, a common practice is to modify the electrospun membrane with low surface-energy materials, such as fluorosilane. However, when directly added to the electrospinning solution, the effects of fluorosilane on the property of the prepared membrane have been scarcely reported. Herein, we prepared the electrospun polyurethane membrane by adding two types of fluorosilane into the polyurethane solution. The effects of fluorosilane type and concentration on the conductivity and viscosity of the electrospinning solution were investigated. Moreover, the prepared polyurethane/fluorosilane fibrous membranes are analyzed in terms of their surface morphology, structure, water contact angle, breathable performance, and mechanical properties. Results show that the dual effects of fluorosilane content exert an opposing influence on the jet drawing process, which yields a minimum fiber diameter when the fluorosilane content is 20%. Under this condition, the membrane shows the highest water vapor transmission rate (10.4 kg/(m2·d). In addition the membranes have the maximum water contact angle (138°) and breaking strength (12 MPa) when the fluorosilane content is 40%. This study provides insights into fabricating electrospun waterproof and breathable membranes in equipment for outdoor sports and protection. [ABSTRACT FROM AUTHOR]

This study aims to study the formation quality of the film of dental silanes. Two dental silanes, 3-methacryloxyproyltrimethoxysilane (MPS) and 3-acryloyloxypropyltrimethoxysilane (ACPS), were deposited on the silica glass-equivalent model surface (i.e., n-type silicon(100) wafer) by varying the deposition time (5 h and 22 h). The film quality was then evaluated by ellipsometry, surface contact angle (CA) and surface free energy (SFE), atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS) in survey and high-resolution modes on Si2p, O1s and C1s. Ellipsometry confirmed that both silanes at the two different deposition times would produce 0.85–1.22 nm thick self-assembled monolayer on the silicon wafer surface. While the water CA of silanized surfaces (60.7–71.5°) was larger than the surface without silane (29.6°), the SFE values of all silanes (40.0–44.5 mN/m) were slightly less than that of the wafer surface (46.3 mN/m). AFM revealed that the MPS with 22 h silanization yielded a significantly higher roughness (0.597 μm) than other groups (0.254–0.297 μm). High-resolution XPS on C1s identified a prominent peak at 288.5 eV, which corresponds to methacrylate O-C*=O, i.e., the silane monolayer is extended fully in the vertical direction, while others are in defect states. This study proves that different dental silanes under various dipping times yield different chemical qualities of the film even if they look thin physically. [ABSTRACT FROM AUTHOR]

Polybutylene terephthalate (PBT) nanocomposites were melt-blended with two types of Turkish halloysite nanotubes (HN). Naturally occurring HN samples were used to produce PBT-based composites at the HN compositions of 1%, 3%, 5%, and 10%. Findings of neat and silane-coated HN-containing composite samples were compared to investigate the interfacial adhesion between polymer matrix and reinforcement material. According to test results, a 1% amount of HN was found to be the most suitable option in the case of mechanical and thermal properties of composites. Additionally, silane-modified grade displayed highly indicative improvements compared to pristine HN clay due to better interfacial adhesion of halloysite nanotubes to the PBT matrix was accomplished. Property enhancements achieved for composite samples containing low contents of HN were confirmed by morphological examinations. As a result, the PBT/ 1% HN-S composite sample was bookmarked as the most suitable option to fabricate HN-reinforced PBT-based nanocomposites in terms of mechanical, thermo-mechanical, morphological, thermal, and physical performances based on the findings in this study. Silane-modified halloysite grades exhibited better results, and they were found to be more suitable in the case of applications of PBT. [ABSTRACT FROM AUTHOR]

This article presents a methodology for functionalization of silicon carbide (SiC) through chemical modification using γ-aminopropyltriethoxysilane (APTES) and its subsequent dispersion in an epoxy composition. The research revealed that functionalizing SiC particles with γ-aminopropyltriethoxysilane (SiC(APTES)) enhanced their chemical compatibility with the epoxy composition, facilitating the dispersion of SiC particles. Furthermore, it was observed that the functionalization of the filler had a profound impact on the structure, curing kinetics, and physical and mechanical properties of epoxy nanocomposites. The addition of SiC(APTES) into the epoxy composition resulted in a significant reinforcement of the material. Specifically, the flexural stress and flexural modulus of elasticity increased by 179% and 74%, respectively, while the impact strength experienced a remarkable improvement of 462%. Additionally, the tensile strength and tensile modulus of elasticity increased by 83% and 70%, respectively, compared to the epoxy composite without SiC. The application of SiC(APTES) also played a crucial role in initiating the polymerization process through the involvement of reactive amino groups, leading to a reduction in the initial curing temperature and an amplification of the thermal effects of the polymerization reaction. Moreover, the presence of functionalized SiC significantly influenced the structure of the epoxy composite, thereby contributing to its enhanced strength. In summary, the inclusion of SiC in the epoxy composition not only bolstered the material but also improved its thermal stability. [ABSTRACT FROM AUTHOR]