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The aim of this study is to provide a review on silanized composite performance when exposed in a complex wet aqueous environment and the role of titanium coupling agent as a more stable and reinforcement material in the construction of dental composites. Silanes are considered as the most dominant materials used for surface modification of the filler added to the polymer material in dental applications. Due to the presence of silica in the silane structure, so, the silane coupling agent were considered to be more effective in modifying materials which are consisting of silica because of the similarity in their ordered structure. Silanes are relatively characterized by dehydration inside the oral aqueous environment. On the other hand, titanate coupling agents are effective in serving at a wet environment, because its ability to react with the positive proton available on the surface of the filler (H+). TCAs are superior in performance in comparison to silane by creating a strong internal bonding between the filler and polymer matrix, and having a significant effect on the dispersion and resolving of particles agglomeration and good hydrolytic stability inside the mouth. This paper presents a comparative study between the effects of silane coupling agents against the TCAs performance in oral environment.

The design of astonishing combinations of benzoxazine resins with various fillers is nowadays of great interest for high quality products, especially in ballistic armors. The objective of this study is to investigate a new hybrid material prepared as multi-layered composite plate by hand lay-up technique. Different composites were manufactured from Kevlar fabrics reinforced polybenzoxazine, which was filled with silane treated microcrystalline cellulose (MCC Si) at various amounts in the interlayers. The developed materials were tested for their flexural, dynamic mechanical and ballistic performance. The aim was to highlight the effect of adding different amounts of MCC Si on the behavior of the different plates. Compared to the baseline, the dynamic mechanical and bending tests revealed an obvious decrease of the glass transition of 21 °C and a notable increase in storage modulus and flexural strength of about 180 %and17%, respectively, upon adding 1% MMC Si as filler. Similarly, the ballistic test exhibited an enhancement in kinetic energy absorption for which the composite supplemented with 1% MCC Si had the maximal energy absorption of 166.60 J. These results indicated that the developed panels, with interesting mechanical and ballistic features, are suitable to be employed as raw materials to produce body armor.

PURPOSE To evaluate the effects of airborne-particle abrasion with alumina particles or silicamodified alumina particles on the bond strength between zirconia and conventional MDP-based (Ph; Panavia F 2.0, Kuraray) or self-adhesive (SA; RelyX U200, 3M ESPE) resin cements. MATERIALS AND METHODS Five surface treatments were evaluated: C = no surface treatment; AB = airborne-particle abrasion with alumina particles (BIO-ART Dental Supplies and Equipment); ABP = AB combined with MDP-based primer (Alloy Primer, Kuraray); SS = airborne-particle abrasion with silica-modified alumina particles (CoJet, 3M ESPE) combined with silane (RelyX Ceramic Primer, 3M ESPE); and SSP = SS combined with MDP-based primer. The surface roughness (Ra) of the airborne particle-abraded samples (n = 5) was measured by a contact profilometer (Mitutoyo Surftest SJ-401, Mitutoyo). Cylinders of the resin cements tested were bonded to the surface-treated zirconia. The microshear test was performed by the application of a load with a wire loop parallel to the adhesive interface until debonding of the resin cement cylinders. The microshear bond strength (μSBS) of the samples was measured before and after being subjected to thermocycling (TC; 5°C to 55°C, 60 seconds dwell time for 3,000 cycles; MSCT, Marcelo Nucci). One-way (Ra) and two-way (μSBS) analysis of variance followed by Tukey post hoc test (α = .05) were used. RESULTS The SS (Ph: 12.6 MPa; Ph-TC: 6.37 MPa; SA: 11.8 MPa; SA-TC: 9.37) and SSP (Ph: 10.4 MPa; Ph-TC: 5.82 MPa; SA: 10.4 MPa; SA-TC: 10.0) surface treatments produced the highest surface roughness values (P < .001). The SS samples achieved the highest immediate bond strength for both resin cements. However, after TC, SA resin cement associated with any surface treatment produced the highest bond strength values. CONCLUSION The self-adhesive resin cement promoted higher and more stable bond strength values when associated with a surface roughening method.

Highly transparent and super-wettable nanocoatings for multifunctional applications with outstanding physical properties are in high demanded. However, such nanocoatings resistant to water invasion and Ultraviolet (UV) weathering remain a significant challenge. In this work, physically durable coatings based on inorganic nanoparticles (NPs) and an organic segment (isocyanate-silane modified surfactant) have been synthesized via a sol-gel approach. It is noteworthy the isocyanate-silane with –NH–C O- functional group creates a strong bonding between the highly hydrophilic surfactant and the inorganic NPs. This in-house synthesized organic segment can render the coating long-lasting wetting properties and resist to be washed away by water, while the inorganic NPs can form sturdy covalent bonds with the nano-scale hierarchical structure on the glazing substrate to improve the durability. This nanocoating demonstrates high transparency with superwetting property (water contact angle, WCA ​= ​4.4 ​± ​0.3°), effective de-frosting performance. Water invasion or UV accelerated weathering tests do not significantly affect the self-cleaning performance of nanocoating. Physical properties, including coating adhesion, hardness, Young's modulus, and abrasion resistance are systematically investigated. Interestingly, this clear coating shows prominent infrared shielding property attributed to Antimony-doped tin oxide (Sb-doped SnO2) NPs. The developed nanocoating process is easy to scale up for larger areas that require multipurpose self-cleaning functions.

The preparation of pH-responsive nanocontainers by typical silane modification of the mesoporous silica nanoparticle (MSN) surface is usually high-cost, complex, and time-consuming, which remains a great challenge for effective corrosion protection of magnesium alloy. Here, a new strategy to construct pH-responsive nanocontainers (MSN-MBT@LDH) is demonstrated. The nanocontainers consist of corrosion inhibitor (2-mercaptobenzothiazole, MBT) loaded MSN core and layered double hydroxide (LDH) nanosheet shell serving as gatekeepers. The successful loading of MBT and encapsulation by LDH nanosheets were confirmed by a series of characterization such as scanning transmission electron microscopy coupled with energy dispersive X-ray spectroscopy (STEM-EDS) and N2 adsorption/desorption isotherms. The pH-responsive feature of the nanocontainers was demonstrated by determination of the MBT concentration in buffer solutions with different pH values. A smart corrosion protection system on Mg alloy is obtained by incorporating the synthesized nanocontainers into a self-assembled nanophase particle (SNAP) coating. The electrochemical tests and visual observations show that the hybrid coating has the best barrier properties and robustness in corrosion protection in NaCl corrosive solutions in comparison with the control coatings. The present method simplifies the synthesis processes of nanocontainers and eliminates the potential detrimental effect of excess gatekeepers on the coating. The findings provide new insights into the preparation of scalable nanocontainers. The self-healing coatings are expected to have widespread applications for corrosion protection of Mg alloy and other metals.

Identifying the correlation between the physical and mechanical properties of the natural plant is important in material characterization by performing the statistical approach. The variation of a type of plant fibre would exhibit a wide range of material properties. The prediction of materials characterization is optimized when the significant elements is identified earlier. Pearson correlation coefficient is calculated from the measurements of physical and mechanical properties from experimental work such as flexural strength and flexural modulus of the composites. A Pearson correlation ruler is used to measure the level of the correlation between the variables. The level of the correlation is between a strong negative relationship and a strong positive relationship. The correlation between the variables is verified using a scatter diagram for each combination of the variables. There is a positive strong linear relationship between the diameter untreated kenaf composite and flexural modulus of kenaf composite with chemical treatment (0.5% silane) with a score of 0.888 of Pearson correlation coefficient. Another interconnection between diameters of (1% silane) kenaf composite with a flexural strength of kenaf composite (0.5% silane) score by 0.891. This finding proves there is an interconnection between the physical and mechanical properties of plant fibre according to the chemical treatment. Lastly, the result can assist researchers to predict significant variables from an experimental result that may optimize the cost and time for the laboratory work.

Silica nanosheets (SN) derived from natural vermiculite (Verm) were successfully incorporated into polyethersulfone–polyvinylpyrrolidone (PES–PVP) polymer to fabricate high–temperature proton exchange membranes (HT–PEMs). The content of SN filler was varied (0.1–0.75 wt%) to study its influence on proton conductivity, power density and durability. Benefiting from the hydroxyl groups of SN that enable the formation of additional proton–transferring pathways, the inorganic–organic membrane displayed enhanced proton conductivity of 48.2 mS/cm and power density of 495 mW/cm2 at 150 °C without humidification when the content of SN is 0.25 wt%. Furthermore, exfoliated SN (E–SN) and sulfonated SN (S–SN), which were fabricated by a liquid–phase exfoliation method and silane condensation, respectively, were embedded in PES–PVP polymer matrix by a simple blending method. Due to the significant contribution from sulfonic groups in S–SN, the membrane with 0.25 wt% S–SN reached the highest proton conductivity of 51.5 mS/cm and peak power density of 546 mW/cm2 at 150 °C, 48% higher than the pristine PES–PVP membranes. Compared to unaltered PES–PVP membrane, SN added hybrid composite membrane demonstrated excellent durability for the fuel cell at 150 °C. Using a facile method to prepare 2D SN from natural clay minerals, the strategy of exfoliation and functionalization of SN can be potentially used in the production of HT–PEMs.

Tapioca starch laminated composite foams were prepared from glyoxal crosslink-tapioca starch and polybutylene succinate (PBS) using corn husks as reinforcement by compression molding technique. Corn husk content was fixed at 1% of crosslinked starch. Both sides of corn husk were treated with silane coupling agents, tetraethoxy silane (TEOS) at 10% and thermo-coated with PBS films at different concentrations (1%, 3% and 5%) by molding at 160 °C. Effect of PBS thermo-coated corn husks on foam morphology, water resistance and mechanical properties were investigated. The SEM micrographs of coated composite foams showed a relatively smooth surface of composite but more cracks were observed as increasing PBS concentration due to thermal degradation of PBS during compressing molding. It was found that impact strength and water resistance of laminar composite foams were increased in thermo-coated with PBS films. Crosslinked tapioca starch laminar composite foams with 3% PBS coated corn husk showed the highest impact strength and water resistance. Thermo-coated method was able to apply to prepare coated PBS on crosslinked tapioca starch laminar composite foams, however thermal degradation of PBS occurred especially at a high concentration which results in poor properties of starch laminar composite foams.

We design an interpenetrating network of silane-functionalized nanocomposites to enhance particle dispersity and interfacial bonding strength in nanocomposites. To qualitatively measure the enhanced particle dispersity in the nanocomposites, we carry out rheological characterizations and suggest a simple particle dispersity index from the viscoelastic responses. Yield stresses of the nanocomposites are obtained by fitting with the Carreau-Yasuda model. After comparing the yield stresses and elastic moduli of the nanocomposites during photo-polymerization, we confirm that interphase regions significantly affect the interfacial bonding and mechanical strengths. Prediction of elastic moduli of the nanocomposites by the Mori-Tanaka micromechanics model agrees well with the experimental data, verifying that a good interpenetrating network exists between the nanoparticles and matrix.

In recent years, bio fibers (such as jute, hemp, flax, nettle, etc) are gaining more attention due their light weight, high specific strength, biodegradability, etc in various applications. Along with this, environmental issue is also an important aspect for maintaining sustainability of the bio fiber based composites. Failure occurs in bio fiber based polymer composites when they are applied to severe loading conditions and the material start degrading. To sustain the lifetime of the bio fiber composites, chemical treatment of the bio fiber is done to enhance the mechanical strength between the bonds so that the amount of stress transferability in the composites is equalized. The most important chemicals sources for the treatments are alkaline, silane, acetylation, benzoylation, acrylation, maleated coupling agents, permanganate, peroxide, isocyanate, stearic acid, sodium chlorite, triazine, derivatives of fatty acids (oleoyl chloride). The present study summarises the studies carried out on the environmental impact and various chemical treatments that were applied to bio fibers for enhancing their properties.

The cryogenic fluid storage and transfer have been an area of interest for space applications. Efficient and safe storage of cryogenic fuels like liquid oxygen and liquid hydrogen is very critical. This study focused on the suitability of (3- Aminopropyl)trimethoxysilane as toughening agents for epoxy resin-based systems for cryogenic applications. We focused on diglycidyl ether of bisphenol A (DGEBA) with triethylenetetramine (TETA) as a curing agent at cryogenic temperatures. (3-Aminopropyl) trimethoxysilane was mixed in Epoxy with the help of a magnetic stirrer and ultrasonicator. CFRP panels made of plain weave carbon fiber and silane modified epoxy were fabricated using Vacuum Assisted Resin Transfer Molding (VARTM) technique. Samples were cut out as per ASTM standards, and Izod Impact test was conducted at room and cryogenic conditions. The toughness was witnessed to be improved at both room as well as cryogenic conditions. Silane successfully reduced the indigenous cross linking density of epoxy, which is making it brittle and stronger at the same time. Silane reduces the indigenous cross linking density of epoxy at cryogenic temperatures, which increases its toughness but at the cost of its overall strength. Also the mechanism of fracture and energy dissipation was studied and summarised using macroscopic fracture analysis and FTIR analysis.

The lack of the required mechanical strength and adequate biodegradation rate of calcium phosphate materials constitutes the most relevant drawback prohibiting their use for orthopaedic applications. One of the promising strategies to overcome this intrinsic limitation is the functionalization of these materials through the combination with specific functional groups. In this study, we investigated APTES (3-aminopropyl-triethoxy-silane) functionalization of a poorly crystalline apatite (PCA) and its further combination for the first time to chitosan (CS) to elaborate PCA-APTES-CS functionalized composite material. XRD patterns of the elaborated materials exhibit broad peaks typical of poorly crystalline apatite. FTIR spectroscopy showed, in addition to the PCA characteristic bands, bands assigned to silane alkyl groups and evidenced the success of functionalization process. The TGA analysis confirmed the attachment of 8 wt% of APTES and 3 wt% of chitosan within the composite. SEM microscopy and EDX silicon mapping demonstrated a homogeneous silane presence on functionalized apatite surface and showed that chitosan enveloped the functionalized apatite particles surface. The elaborated PCA-APTES-CS functionalized composites exhibited compressive strength similar to the spongy bone. The functionalized biocomposite will be investigated as potential biomaterial for orthopedic application.

In this study, NH2-MIL-101(Al) metal-organic frameworks (MOFs) covered with 3-aminopropyltriethoxysilane (APTES) were incorporated into the polyethersulfone (PES) to produce mixed-matrix membranes (MMMs) for CO2 separation. The APTES functionalization was performed to improve the MOF dispersion in the PES matrix. Different analyses such as X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), and field emission scanning electron microscopy (FESEM) revealed that the MOFs surface successfully functionalized with APTES. An improvement in CO2/CH4 separation efficiency was observed in MMMs, and the performance shifted towards Robeson upper bounds. Notably, the membrane containing 10 wt.% S-MIL-5 (NH2-MIL-101(Al) functionalized with 5.0 mL of APTES) showed an increment in CO2 permeability (50%), and ideal CO2/CH4 selectivity (80%) compared to the PES membrane. The FTIR, TGA, FESEM, and DSC analyses constituted an excellent dispersion of MOFs within the PES phase, which led to significant development in gas permeability and selectivity.

In the presented research, two trialkoxysilanes were used to investigate their reactivity with microcrystalline cellulose (MCC) applied as a model material. As a continuation of the previous study, the research aimed at evaluation of the durability and potential reversibility of the silane treatment. Two different solvents and a mixture thereof were used for cellulose modification. The influence of amino group/pH, an excess of silanes and re-soaking with water on binding with cellulose was examined. The results obtained confirm that both selected silanes can effectively modify MCC. However, the treatment with 3-(2-aminoethylamino)propyltrimethoxysilane occurred more effective than with Methyltrimethoxysilane due to the presence of amino groups. Among the three tested solvents, the most effective was pure water. In contrast, the use of ethanol and a mixture of ethanol and water gave significantly worse results. Summarising, the presented research clearly shows how important the type of the functional group in alkoxysilanes is for its chemical reactivity with natural polymers, which is crucial for their application in waterlogged wood conservation.

The combination of the method for measuring of the number of active centers by quenching of polymerization by radioactive carbon monoxide with fractionation of polymers obtained by TREF method (temperature rising elution fractionation) to the separate fractions with different isotacticity has been used for determination of the number of active centers with different isospecificity (C Pi) responsible for the formation of Fi fractions as well as for calculation of propagation rate constants (kPi) for these centers. Data on the effect of catalyst composition on the CPi and kPi values have been obtained for the first time for polymerization with three types of titanium-magnesium catalysts with different internal stereoregulating donors (di-n-butyl phthalate – TMC-D, 2,3-di-iso-butyl-diethyl succinate – TMC-S, 9,9-bis(methoxymethyl)-fluorene – TMC-F) and for catalytic system TMC-D with external stereoregulating donor – cyclohexylmethyl(dimethoxy)silane. The possible structures of active centers with different isospecificity are discussed on the base of experimental data obtained on the CPi and kPi values.

Natural fibres have recently become an attractive alternative to synthetic fibres in the implementation of polymer composite structures. Inherent flaws within natural fibres in terms of their constituent contents (hemicellulose, cellulose, and lignin) reduce the compatibility of these fibres with polymer matrices. In this study, the effects of chemical treatments on hemp fibres and the resulted polyester matrix composite are investigated. The fibres were treated with alkali (0–10% NaOH), acetyl, and silane chemicals. Long unidirectional fibre composites were prepared by vacuum-assisted resin transfer moulding (VARTM) process. Thermal properties of the fibres were tested using differential scanning calorimetry (DSC) analyses. The mechanical properties of the composite samples were tested using compression and bending tests. Failure analysis of tested composites was undertaken through Optical Microscope (OM) and Scanning Electron Microscope (SEM). The results showed that the treatments of the 4% NaOH reduced interfacial bonding strength and decreased composite properties compared to untreated samples. At higher concentrations (6–10% NaOH), the mechanical properties of the composites increased as a result of greater interfacial bonding. Different trends were observed in the case of alkalised fibres that were further treated with acetyl and silane treatments. It was observed that the treated fibres effectively improved the bonding properties of composites and was in agreement with the micrographs.

The present work discusses the effects of reduced graphene oxide (rGO) on the nonlinear viscoelastic behavior, or the Payne effect, of silica/styrene-butadiene rubber compounds. The volume fraction of unmodified silica was constant, while the amount of rGO in these hybrid filler compounds varied. Dynamic-mechanical analysis (DMA) in strain sweep mode showed that adding a small quantity of rGO to the silica-filled compounds resulted in diminished network formation of unmodified silica as well as a reduced Payne effect and corresponding energy dissipation. The state of silica dispersion in the presence of rGO in the rubber matrix was predicted by calculating the work of adhesion in a three-component system and detected by scanning electron microscopy. It was observed that the dispersion of the unmodified silica was improved by the addition of only 0.25 or 0.5 phr rGO, which may be due to the improved silica-rubber interactions that occur during mixing and/or reduced silica flocculation after mixing, as measured by DMA in time sweep mode. The synergy between silica and small quantities of rGO (0.25 or 0.5 phr) resulted in an enhancement in mechanical strength (45%) and abrasion resistance (63%), as well as a reduction in heat build-up (23%). This hybrid system can be considered an alternative to silane modification of silica in green tire technology. Effect of graphene (rGO), as the secondary filler, in rubber compounds filled with silica was investigated. Scanning electron microscopy showed that silica dispersion was improved in the presence of small quantities of rGO, but it deteriorated at higher loadings of rGO due to the formation of compact hybrid filler network. This morphological development affects dynamic-mechanical properties such that the Payne effect reduces in the presence of low concentrations of rGO. Using these observations, the underlying mechanism was explained based on how rGO hinders silica reagglomeration thermodynamically after the mixing.

Difluoroboryl complexes obtained from N-acyl hydrazones upon brief treatment with boron trifluoride and allylic silane serve as efficient acceptors of alkyl radicals. The reaction of the boryl chelates with carboxylic acids in the presence of an acridine-type photocatalyst leading to N-acyl hydrazides is described. The efficiency of addition at the C═N bond of the chelates is determined by the formation of a nitrogen-centered radical stabilized by the boron-containing heterocyclic ring.

Reducing the parasitic absorption of intrinsic hydrogenated amorphous silicon [a-Si:H(i)] films is crucial for enhancing the short-circuit current density (Jsc) of silicon heterojunction (SHJ) solar cells. Herein, a-Si:H(i) films were replaced by intrinsic hydrogenated amorphous silicon oxide [a-SiOx:H(i)] films with wider band gap at the front of rear-emitter SHJ solar cells and the microstructure of a-SiOx:H(i) films was modified with the flow ratio of carbon dioxide to silane. A-SiOx:H(i) films showed lower absorption coefficients at short wavelengths and led to a 0.13 mA/cm2 absolute increase of Jsc. Additionally, higher open-circuit voltages (Voc) were achieved thanks to the better interface passivation and the fill factors (FF) almost kept constant due to avoiding the impediment of hole transport. However, the higher oxygen content in a-SiOx:H(i) films associated with the worse electrical performance hence carbon dioxide-to-silane flow ratio should be adjusted at a low value. Finally, a conversion efficiency (Eff) gain of 0.12%abs was obtained for the optimized SHJ solar cells as a result of the improvements of both Voc and Jsc. More importantly, a-SiOx:H(i) layer exhibited better damp-heat stability than a-Si:H(i) layer in sodium environment. This work clearly interpreted the functions of oxygen atoms in a-SiOx:H(i) films and offered a valid approach to reducing the parasitic absorption losses of SHJ solar cells.

In this study, we investigate the reaction mechanisms of precursor adsorption during the atomic layer deposition (ALD) using density functional theory (DFT) calculations and ideal-gas methods; herein, we considered adsorption of tris(dimethylamino)silane (TDMAS) on a hydroxylated SiO2 surface to be the example for our investigation. When the reaction free energy is calculated, the DFT results obtained at 0 K suggest that the dissociation of a hydrogen atom from TDMAS is favorable upon TDMAS adsorption, which is inconsistent with the experimental results where one dimethylamino group is released. The experimental results can be accurately predicted when enthalpy and entropy changes are considered at elevated temperatures, thereby indicating the significance of finite-temperature effects in free-energy changes for solid-gas reactions. We analyze the changes in enthalpy and entropy and find that dimethylamine is a more favorable gaseous product than H2 owing to its larger translational and rotational entropy.

To effectively immobilize an enzyme while maintaining its high activity and stability, the design of supports with controlled geometric structures and heterogeneous surface properties is desirable. Towards this goal, heterogeneous titanium dioxide (TiO2) surfaces with controlled pore sizes were synthesized in this study and used to efficiently immobilize lipase. The immobilized lipase activity increased by a factor of 1.31 with an increase in the TiO2 pore size from 11.46 to 21.14 nm. The highest protein loading of 15.52 mg/g was achieved in ethenyl triethoxy silane (ETS)-modified TiO2 (E-P25) after immobilizing the enzymes at 30 ℃, pH 7.33 for 3 h and using a protein concentration in solution of 0.176 mg/mL. Among the different surface functionalities, the highest activity yield of 428.04 % was accomplished by using TiO2 calcinated at 650 ℃ and modified by ETS as immobilization support. The immobilized enzymes showed excellent storage stability and retained almost 95 % of their activity after being stored at 4 ℃ for 8 weeks. This research provides experimental evidence that highlights the importance of studying of enzyme immobilization on the supports with synergistically designed geometric structures and surface chemical properties.

The present study aims to develop multilayer barrier-bioactive hybrid sol-gel coatings from a mixture of the silane precursors tetraethylorthosilicate (TEOS) and glycidoxypropyltriethoxysilane (GPTMS) deposited on the Elektron 21 magnesium alloy. The purpose of the inner layer (barrier coating) was to provide corrosion protection to the magnesium alloy, whereas the outer layer (bioactive coating) was doped with different Ca and Mg contents to produce a bioactive material. The coatings were characterised using scanning electron microscopy (SEM) and their corrosion behaviour was evaluated by anodic polarisation and electrochemical impedance spectroscopy after immersion in simulated body fluid (SBF) at 37 ± 0.5 °C. The experimental results showed that the multilayer coatings increased the corrosion resistance of the alloy up to three orders of magnitude during immersion in SBF solution. On the other hand, the presence of Ca and Mg in the bioactive coating promoted the growth of apatite-like phases. However, an increment of salt content favoured the formation of porous coatings, which allowed the access of the electrolyte to the substrate leading to their rapid deterioration. Despite the latter, this research endorses the premise that the TEOS-GPTMS hybrid system represents a promising alternative to produce bifunctional barrier-bioactive coatings.

The aim of the present study was to investigate the effects of fiber content and then silane treatment on the mechanical performance of the natural fiber composites of recycled acrylonitrile–butadiene–styrene (ABS) provided by the automotive sector. Wood and palmyra fibers were used as fillers in 10% and 20% fiber content composites. The fibers were treated with N-(2-Aminoethyl)-3-aminopropyltrimethoxysilane to improve the interfacial adhesion between fibers and polymer matrices. The mechanical properties of the composites were determined by tensile and impact tests. Morphological analysis was later performed using a scanning electron microscope (SEM). According to the experiment results, the tensile and impact strength of both wood and palmyra fibers increase after silane treatment. However, for the low-wood-fiber-content composite, the tensile and impact strength decrease after silane treatment due to the presence of an excess amount of silane relative to fiber content. The addition of wood and palmyra fibers significantly improved the tensile modulus of composite material and further increases slightly after silane treatment. Finally, SEM analysis shows a homogenous mix of fibers and polymer matrices with fewer voids after silane treatment, thereby improving interfacial adhesion.

Ethynylsilylene (HCCSiH; X1A') has been prepared in the gas phase through the elementary reaction of singlet dicarbon (C2) with silane (SiH4) under single-collision conditions. Electronic structure calculations reveal a barrierless reaction pathway involving 1,1-insertion of dicarbon into one of the silicon-hydrogen bonds followed by hydrogen migration to form the 3-sila-methylacetylene (HCCSiH3) intermediate. The intermediate undergoes unimolecular decomposition through molecular hydrogen loss to ethynylsilylene (HCCSiH; Cs; X1A'). The dicarbon-silane system defines a benchmark to explore the consequence of a single collision between the simplest "only carbon" molecule (dicarbon) with the prototype of a closed-shell silicon hydride (silane) yielding a nonclassical silacarbene, whose molecular geometry and electronic structure are quite distinct from the isovalent triplet propargylene (HCCCH; C2; 3B) carbon-counterpart. These organosilicon transients cannot be prepared through traditional organic, synthetic methods, thus opening up a versatile path to access the previously largely elusive class of silacarbenes.

The importance of adding surface treated Ramie fibre and nanoclay in epoxy resin composites was investigated in this research. The key goal of this study was to demonstrate the significance of surface treatment on naturally occurring fibres and fillers as they are indented for use in high-performance composites. The surface of the Ramie fibre was treated using an amino silane whereas the nanoclay was organo-montmorillonite (OMMT). The composites were made using a hand layup process of 40 vol% Ramie fibre and 0.5, 1.0, 1.5, 2.0, and 2.5.% nanoclay reinforcement. The specimens are then tested for various mechanical properties such as tensile, flexural, impact, and hardness in accordance with ASTM standards in order to determine the composite’s strength. Wear and fatigue properties were also investigated to determine the outcome of surface-treated fibre and particle in a polymer matrix. The mechanical properties of the 40 vol% Ramie fibre and 1.5 vol% OMMT nanoclay are found to be better. Wear tests showed that a composite containing 40vol. % of fibre and 1.5vol.% of OMMT nanoclay produced high abrasion resistance. Similarly, fatigue life counts of composites containing 1.0vol. % nanoclay shows 44,218 cycles. Water absorption resistance is balanced because of silane-treated ramie fibre and OMMT nanoclay in epoxy composite. There is no vast decrement in hydrophobicity on compare with bare resin. The SEM images show exfoliation of OMMT nanoclay in the matrix as well as increased Ramie fibre adhesion to the matrix.

In this paper, three different methods (secondary growth method, in situ hydrothermal method and hot pressing with silane method) for synthesizing silicalite-1 molecular sieve anti-corrosive film on open-cell aluminum foam surface were studied, and the silane coupling agent was used as a connecting layer to enhance the bonding force. The surface morphology was observed by scanning electron microscopy, the phase composition was analyzed by x-ray diffraction, and the corrosion resistance was predicted by electrochemical test results. It was shown that the silicalite-1 anti-corrosion film prepared by the secondary growth method has the best surface, crystallinity (more than 98%), anti-corrosion performance, and good hydrophobicity. Finally, through Raman Microscopy test, the film formation mechanism of the secondary growth method was analyzed. The results show that the initial hydrogen bonds between the hydroxyl groups of the molecular sieve particle and the hydroxyl groups of the silane coupling agent change to covalent bonds due to the dehydration condensation reaction, and other free hydroxyl groups react in the same way with the hydroxyl groups on the aluminum foam surface.

3-Aminopropyltriethoxysilane (APTES) is one of the most important silicon compounds in chemistry for the synthesis of materials. It has extensively been used as a silanization agent for the chemical modification of metal oxide nanoparticle (MONP) surfaces. The introduction of amine (NH2) enhances their dispersibility and anti-bacterial property. The APTES-MONPs have various direct applications in electrochemical sensors, catalysts and Pickering emulsions. In this review article, exemplary APTES modifications of MONPs for unique biomedical, industrial and scientific applications are highlighted. APTES modification provides a linkage for numerous organic, inorganic, or biochemical attachments that are essential to drug delivery, contaminants removal, catalyst immobilization, and medical imaging.

The purpose of this research was to investigate the time-dependent behaviour of an epoxy composite prepared from silane-treated aramid fibre and waste latex rubber powder (LRP). To increase the adhesive behaviour of reinforcement with matrix, the aramid fibre and latex rubber powder were surface treated using amino silane. The composites were made using hand layup method and cured at room temperature. The fatigue strength of LRP in fibre-epoxy composite was improved up to 82.1 % when compared to fibre-epoxy composite. Similarly, incorporating LRP into the resin increased the energy storage up to 4.7GPa, which was equal to 34.04 % with neat epoxy. The addition of latex rubber powder to the resin enhanced the energy dissipation factor in dynamic mechanical analysis (DMA). These mechanically toughened epoxy composites made from industrial crop waste could be used in engineering applications that demand great toughness and stiffness.

Silicon has become one of the most emerging anode materials in Li-ion batteries due to its excellent specific capacity. The incorporation of binders can significantly reduce the volume expansion of silicon during the cycling process. In this work, a novel type of cross-linked siloxane-based copolymer, poly (tert-butyl acrylate-co-vinyl tri-lactate ethyl silane) (TBA-VTLES) was designed and utilized as the binder for the silicon anode in Li-ion batteries to alleviate the inner stress of adverse volume changes and improve the electrochemical performance. The hard TBA and soft VTLES were interwoven into a 3D network to achieve the adhesive action via free radical polymerization. The soft chains in TBA-VTLES can enhance the cohesion of the copolymer to disperse residual stress, and thus avoid structural damage during lithiation. Meanwhile, the rigid chains can provide sufficient mechanical strength to maintain the integrity of silicon anode during de-lithiation. Moreover, the presence of TBA-VTLES can improve the adhesive strength between the copper collector and the binder. This novel type of siloxane-based copolymer binder with hardness and softness provides a feasible way to improve the silicon anode performance of Li-ion batteries. The synthesized cross-linked copolymer binder can improve the interfacial interaction and electrochemical performance of Si anode-- present in Graphical abstract figure-- need or not.

There are growing research interests in flax fibers due to their renewable ‘green’ origin and high strength. However, these natural fibers easily absorb moisture and have poor adhesion with polymer matrix leading to low interfacial strength for the composites. A hybrid chemical treatment technique combining alkali (sodium hydroxide) and silane treatments is adopted in the current study to modify flax fibers for improved performances of flax/polypropylene composites. Changes in chemical composition, microstructure, wettability, surface morphology, crystallinity and tensile properties of single flax fiber before and after chemical treatments were comprehensively characterized using techniques including SEM, FTIR, AFM, XRD, micro-fiber tester, etc. It was found that hemicellulose and lignin at the fiber surface were removed due to alkali treatment, which helped to reduce moisture absorption of the composites. Alkali-treated flax fibers were later subjected to silane treatment, which helped to improve the compatibility between flax fiber and polypropylene matrix. After alkali-silane hybrid chemical treatment, moisture absorption of the composites was further decreased. At the same time, the interfacial bonding strength between flax and polypropylene is significantly enhanced. All these results validate the great advantage of the hybrid chemical treatment approach for flax/polypropylene composites, which has the potential to promote the application of chemical treatment techniques in the plant fiber composite industry.

Commercially available Pd/C can be used as a catalyst for nitro group reductions with only 0.4 mol % Pd loading. The reaction can be performed using either silane as a transfer hydrogenating agent or simply a hydrogen balloon (∼1 atm pressure). With this technology, a series of nitro compounds was reduced to the desired amines in high chemical yields. Both the catalyst and surfactant were recycled several times without loss of reactivity.

Highly hydrophobic surface property is important for many applications, such as anticorrosion, antifogging, and antifouling. With regard to some practical applications, both mechanical endurance and thermal stability are essential. Here, we report a new method for making highly hydrophobic surfaces with simultaneously enhanced mechanical endurance and thermal stability. Such high-performance hydrophobic surfaces were prepared by coating electrospraying derived fluorinated SiO2 particles on various substrates, including glass slide, ceramic wafer, metal foil, and polymer sheet, with methyl silicone resin as the binder. Fluorinate silane was homogenously doped in the matrix of SiO2 particles, which can provide excellent protection effect. Meanwhile, the thermally stable methyl silicone resin can afford strong binding force between SiO2 particles and the substrates. Therefore, the hydrophobic surfaces created here possess both high mechanical endurance and excellent thermal stability.

A facile strategy for the fabrication of a carbon shell on Fe3O4 nanoparticles with a cluster structure has been proposed. Unlike the conventional solvothermal process using an autoclave, the proposed synthesis method could yield core-shell structured Fe3O4@C nanoparticles at low temperature and atmospheric pressure. This synthesis method was based on the chemical bonding among the terminal amine groups, introduced on the Fe3O4 surface, and carbonization by the catalytic reaction of glucose (carbon source) with sulfuric acid. The properties of the Fe3O4@C nanoparticles so obtained depended on the terminal amine groups that modified the iron oxide surface. The effects of the silane- and polymer-based amination on the fabrication of the carbon shell were investigated.