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Copyright of Silicone Material is the property of Silicone Material Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Silicone Material is the property of Silicone Material Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The abradable coating is one of the significant stator components in aero-engine，which protects the rotating blade and casing by abrading itself and improves the engine performance by reducing the gap between the rotor and stator. In this study，taking the addition-type silicone resin as the matrix，the effect of diameter and stacking density of glass hollow/solid microspheres on the processability of abradable coating was investigated. Moreover，the effect of glass microsphere type and content was illustrated using a self-designed wear tester simulating the working conditions of stator in aero-engine. The results show that the silicone resin reinforced by H-type （size distribution 20–820 um） hollow glass microspheres exhibits excellent surface quality，flowability and comprehensive performance. The suitable preparation technology of abradable coatings was developed by glass microsphere selection，content controlling，tool design and infusion parameters optimizing. The as-prepared glass microsphere/silicone abradable composite is successfully applied and verified in aero-engine stator component.

To enhance protection against corrosion and ice on iron metal material in frigid zones, an organic silicone resin coating was prepared using four monomers. Its structure and performance was analyzed via infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), gel permeation chromatography (GPC), and thermal analysis (TG). Corrosion resistance of coating was tested by saltwater resistance and salt spray resistance and assessed using an electrochemical workstation, alongside anti-icing tests. The results showed that the organic silicone resin was successfully synthesized. The coatings could delay freezing onset by one-third compared to controls in low temperatures, with a detachment time also reduced by one-third, indicating excellent corrosion and ice resistance. The methylphenyl silicone resin had good anti-corrosion and anti-ice properties, with a low corrosion current density (icorr) of 0.8793 μA/cm2 and a high charge transfer resistance (Rct) of 24,930 Ω·cm2 in saline. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Aeronautical Materials is the property of Editorial Board of Journal of Aeronautical Materials and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

According to the published articles, the capacity and output of silicone methyl monomer, the import and export of primary polysiloxane, the revenue of listed enterprises in silicone, the new projects, the formulation of policies in silicone in 2023 were summarized, and the R&D in silicone (including R&D investment of enterprises, self-developed projects of enterprises and R&D priorities in silicones) was also introduced. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study enhances the water resistance of mica paper/organic silicone resin composites through surface modification with 3-aminopropyltriethoxysilane (APTES). The Fourier-transform infrared spectroscopy and the X-ray photoelectron spectroscopy confirmed the formation of chemical bonds between APTES and mica. The results showed that at an optimal APTES concentration of 0.6%, the water diffusion coefficient decreased from 5.0 × 10−3 mm²/min to 2.7 × 10−3 mm²/min, and the permeability coefficient decreased from 5.71 × 10−4 mm²/min to 1.94 × 10−4 mm²/min, with a significant reduction in equilibrium water uptake. Additionally, the modified composites exhibited minimal mechanical strength loss after moisture aging, demonstrating excellent water resistance. The interface shear strength tests revealed a 28.6% increase in interfacial bonding strength after APTES modification. This study demonstrates the potential of silane coupling agents to enhance the performance of inorganic polymer composites, providing theoretical support for their industrial application.

The properties of thermal sprayed WC based cermet coatings are limited by their structural defects, especially corrosion resistance. This article studied the influence of vacuum sealing with silicone resin on the long-term corrosion resistance of HVOF sprayed WC-Cr3C2-Ni coating in 3.5 wt.% NaCl solution. The surface morphologies of the unsealed and sealed coatings show the high compatibility between sealant and WC-Cr3C2-Ni coating. Benefiting from the block of sealant in defects, the sealed coating presents lower corrosion current density (5.843 × 10−8 A cm−2) after long-term corrosion than the unsealed coating (1.776 × 10−7 A cm−2). Owing to the vacuum treatment, sealant adequately penetrates and remains inside the WC-Cr3C2-Ni coating, and inhibits the growth of corrosion pits on the sealed coating surface. The vacuum sealing with silicone resin effectively hinders the diffusion of corrosion solution, and provides practicable strategy to improve the corrosion resistance of the coatings.

In this study, the WC–20Cr3C2–7Ni/MWCNTs coating was prepared by high-velocity oxy-fuel (HVOF) spraying. Coatings were sealed with two types of sealants (i.e., silicone resin and aluminum phosphate) using both conventional and vacuum impregnations. Sealing treatments were investigated for their effect on coating microstructure and electrochemical corrosion behavior by scanning electron microscopy (SEM), contact angle measurement, electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization. According to the results, all four sealing methods enhanced the coating's corrosion resistance. The vacuum impregnation sealing process removed residual air from pores and microcracks, permeating these defects as much as possible with the sealants. In contrast to silicone resin sealants, aluminum phosphate sealants had the opposite effect on sealing since bound water evaporated during heat treatment, which contributed to the formation of defects in the path as a result of the thermal stress. Among all four sealing methods, sealing with silicone resin organic sealant under vacuum impregnation had the highest charge transfer resistance (Rct) and polarization resistance (Rp), the lowest free corrosion current density (Icorr), and the largest capacitive arc radius and impedance modulus, which significantly improved the coating's corrosion resistance.

In this study, a silicone resin solution was used as a supplementary binding agent, and two different techniques were employed to add varying amounts and layers of Al 2 O 3 fibers within the shell to improve the performance of investment casting shells. The Al 2 O 3 fiber-toughened shells were characterized using a combination of three-point bending and high-temperature self-loading deformation experiments. Additionally, the fracture morphology of samples and the fiber failure mode were demonstrated through SEM (Scanning Electron Microscope). Results showed that the added Al 2 O 3 fibers greatly improved the bending strength and the high-temperature self-loading deformation of the ceramic shells. After spraying the silicone resin solution, the green and sintered strengths of the shells reached 8.02 MPa and 9.60 MPa, respectively, when Al 2 O 3 fibers were added to the 3–6 layers of the shell. The high-temperature self-loading deformation reached a minimum of 0.44% when Al 2 O 3 fibers were added at 0.4 wt%. SEM analysis indicated that the incorporation of Al 2 O 3 fibers in the backing sand resulted in a disordered and non-directional distribution pattern, which could lead to the splitting of the ceramic matrix. In contrast, Al 2 O 3 fibers within each shell layer could uniformly disperse the external load and increase the fracture resistance of the substrate. Furthermore, the pyrolysis of the silicone resin led to the deposition of free carbon in the matrix pores, resulting in the spontaneous formation of SiC nanowires. These nanowires were observed to attach to the Al 2 O 3 fibers, which ultimately impeded the propagation of matrix cracks. [Display omitted] • The Al 2 O 3 fibers were incorporated into the ceramic shell using two different methods. • The SiC nanowires were formed within the matrix as an auxiliary reinforcing phase after the pyrolysis of the silicone resin. • The baked strength and self-loading deformation rate of the modified shell was increased by 5.42 MPa and 0.16, respectively. • The failure modes of Al 2 O 3 fibers in the ceramic matrix were self-fracture, pull-out, and debonding. [ABSTRACT FROM AUTHOR]

Silicone resin is a coating material with good performance. The improvement of its thermal stability and hydrophobicity has always been the pursuit of researchers. In this paper, a series of novel UV-curable silicone resins containing perfluorocyclobutyl (PFCB) groups were prepared by co-hydrolytic polycondensation. The structures of the resin precursor MDT-SH were characterized by FT-IR and 1H NMR. The heat resistance of them was studied by TGA and DSC, and results show that the PFCB groups can significantly improve the high temperature resistance of the resins. Contact angle tests showed that hydrophobicity of them was also enhanced by the PFCB groups. [ABSTRACT FROM AUTHOR]

Copyright of Electroplating & Finishing is the property of Electroplating & Finishing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Based on the excellent physical properties and flexible molecular modifiability, modified silicone resins have received favorable attention in the field of microelectronics, and recently a number of modified silicone resins have appeared while few breakthroughs have been made in low dielectric constant (low-k) materials field due to the limitations of structure or the curing process. In this work, functional silicone resin with different BCB contents was prepared with two monomers. The resins showed low dielectric constant (k = 2.77 at 10 MHz) and thermal stability (T5% = 495.0 °C) after curing. Significant performance changes were observed with the increase in BCB structural units, and the functional silicone obtained does not require melting and dissolution during processing because of good fluidity at room temperature. Moreover, the mechanical properties of silicone resins can be also controlled by adjusting the BCB content. The obtained silicone resins could be potentially used in the field of electronic packaging materials. [ABSTRACT FROM AUTHOR]

According to the published literature and information, the capacity and output of silicone methyl monomer, the import and export of primary polysiloxane, the revenues of listed silicone enterprises, the new projects, the formulation of policies and standards in silicone in 2022 were summarized, and the R&D in silicone industry (including R&D investment, self-developed projects and R&D priorities) was also introduced. [ABSTRACT FROM AUTHOR]

UV-curable silicone prepolymer was synthesized by hydrolytic condensation by tetraethyl orthosilicate (TEOS) and γ-methacryloxypropyltrimethoxysilane (KH 570), which can be quickly 3D-printed by light curing LCD 3D printer. The composition and structure of silicone resin were characterized by FTIR and H NMR spectroscopy, and the UV-curing kinetics of silicone prepolymer was studied by HAAKE torque rheometer and RT-IR spectrum. The influence of different mole ratios of TEOS to KH 570 on silicone prepolymer for rapid UV-curing 3D printing were investigated. The results showed that the silicone prepolymer with excellent comprehensive performance and fast UV-curing 3D printing was successfully prepared. When the ratio of TEOS/KH570 was 5:5, its critical exposure was 4.431 mJ/cm², curing depth was 0.5226 mm, and the 3 D-printed silicone prepolymers showed good comprehensive properties. [ABSTRACT FROM AUTHOR]

In this work, effects of the silicone resins on copolymerization of the acrylated epoxidized soybean oil were investigated. Rheological characteristics, curing behaviors, and thermal properties of acrylate epoxy soybean oil prepolymer (AP), silicone prepolymer (SP), and their hybrids (AP/SP) were studied in detail. Spots in a snowflake pattern were observed on the fracture section surface of cured AP/SP hybrid resins by SEM. According to the change of polymer groups revealed by Fourier transform infrared, a possible reaction between AP and SP was proposed. The curing mechanism of AP/SP hybrids was researched, which was suggested to be an autocatalytic curing process. Furthermore, the degree of cure, the activation energy (Eα) and the reaction frequency factor (A) of the curing reaction were estimated. It was found that the cure kinetic of AP/SP hybrid resins could be well‐described by a Sesthk‐Bergglen model with the numerical optimization based on the Kissinger method and the Malek approach. The experimental results show that the mass retention rates of AP/SP hybrid resins were significantly increased after curing, indicating that the thermal stability of AP was enhanced with the addition of SP. [ABSTRACT FROM AUTHOR]

In the field of flexible electronics manufacturing, inkjet printing technology is a research hotspot, and it is key to developing low-temperature curing conductive inks that meet printing requirements and have suitable functions. Herein, methylphenylamino silicon oil (N75) and epoxy-modified silicon oil (SE35) were successfully synthesized through functional silicon monomers, and they were used to prepare silicone resin 1030H with nano SiO2. 1030H silicone resin was used as the resin binder for silver conductive ink. The silver conductive ink we prepared with 1030H has good dispersion performance with a particle size of 50–100 nm, as well as good storage stability and excellent adhesion. Additionally, the printing performance and conductivity of the silver conductive ink prepared with n,n-dimethylformamide (DMF): proprylene glycol monomethyl ether (PM) (1:1) as solvent are better than those of the silver conductive ink prepared by DMF and PM solvent. Cured at a low temperature of 160 °C, the resistivity of 1030H-Ag-82%-3 conductive ink is 6.87 × 10−6 Ω·m, and that of 1030H-Ag-92%-3 conductive ink is 0.564 × 10−6 Ω·m, so the low-temperature curing silver conductive ink has high conductivity. The low-temperature curing silver conductive ink we prepared meets the printing requirements and has potential for practical applications. [ABSTRACT FROM AUTHOR]

Self-stratifying coatings facilitate segregation of two distinct and inter connected coating layers with complimentary properties in a single shot application. This novel process thus obviates the need for multiple coating steps. In the current work, we report the effect of pigmentation on self-stratification of a solvent-free coating system comprising incompatible polymer blends of epoxy and silicone resins. The resins were pigmented to impart anticorrosive properties to the epoxy layer (pigment volume concentration, PVC of 10, 20 and 30% using red iron oxide) and weathering resistance to the silicone resin using TiO2 (a fixed PVC of 10%). A series of complimentary analytical techniques were employed to probe the degree of stratification of the cured coating at different length scales, namely contact angle goniometry, attenuated total reflectance-Fourier transformed infrared spectroscopy, scanning electron microscopy and energy-dispersive X-ray spectroscopy. There were evidence of TiO2 migrating towards epoxy and iron oxide towards silicone resin, even though, the pigments were properly dispersed in their corresponding resins. This implied significant effect of PVC on stratification of epoxy and silicone resins. Rheological studies were employed to epoxy, silicone resin and their pigmented mixture to understand the curing behaviour as well as to understand its effect on stratification process. We also scrutinized the outcome of constrained stratification on thermo/mechanical and anticorrosive performance of the coatings. Contact angle values obtained for top surfaces of all PVC, i.e., 10, 20 & 30 stratified coatings were found to be > 106°and shows hydrophobicity and the bottom coat was found to be < 50° which is more hydrophilic in 20 & 30 PVCs coatings. The 20 PVC coating showed clear stratification, optimal anticorrosive and hydrophobic properties as revealed by electrochemical impedance spectroscopy and contact angle goniometry studies, respectively. [ABSTRACT FROM AUTHOR]

• The PDA-PEI@octaphenyl-POSS acted as the modulus transition interface was successfully constructed between CF and SR. • The thermal and mechanical properties of the CF/SR composites improved due to the "soft-rigid" structural interface. • The interface improved the hardness management and maintained the antistatic properties after the bending and heating. To avoid a large difference in modulus between carbon fiber (CF) and silicone resin (SR) and unstable thermal properties, the "soft-rigid" structural interface is constructed by coating polydopamine-polyethyleneimine@octaphenyl-silsesquioxane (PDA-PEI@octaphenyl-POSS) on the fiber surface. The tensile strength of the CF-AE@3P/SR composite was 24.35 % higher than that of the unmodified CF/SR. The mechanism of mechanical enhancement revealed that the rigid layer with nanoparticles effectively deflected the crack and prolonged the path, and the hydrogen bonds and van der Waals forces helped disperse the stress concentration at the interface. The defects in the soft–rigid structural interface were reduced, and the decomposition of the fibers and composites was effectively inhibited, thereby increasing the heat transmission in the composites. After heating for 20 s on the heating plate at 200 °C, the surface temperature of the CF-AE@3P/SR composite was 155.4 °C, which is higher than that of the unmodified CF/SR (131.4 °C). Therefore, the thermal stability of the CF-AE@3P/SR composites was significantly improved compared to that of unmodified CF/SR after holding at 350 °C for 3 h. Surface resistance analysis showed that the soft–rigid modification maintained the antistatic properties of the composites at room and high temperatures. It was also found that the CF-AE@P/SR composites exhibited good flexibility, lightweight, and hardness for application in sealing and electronic components. This work provides ideas for forming a seamless transition and effective bonding between high-modulus carbon fibers and a low-modulus elastomer matrix, increasing the thermal stability and mechanical properties, and maintaining the flexibility, stiffness, lightweight, and antistatic properties of composites at high temperatures. [ABSTRACT FROM AUTHOR]

Heat-resistant magnetic microwave absorption coatings are vital important for the stealth safety of apparatus working at elevated temperature or electromagnetic compatibility of high density/power electronic devices. In this work, we proposed a heat-resistant coating with nanocrystalline FeCoCr micropowders as the absorbents and silicone resin as the matrix. The evolution of microstructure, absorption and adhesion of FeCoCr/silicone resin coatings were investigated after heat treatment at 400°C. The results show that the roughness of FeCoCr powders slightly increased due to the formation of nanoparticles, while their crystalline phase maintained body-centered cubic structure with grain size increasing from 10.8 nm to 18.1 nm after heat treatment. The saturated magnetization and coercivity of FeCoCr powders also increased after heat treatment. The adhesion of FeCoCr/silicone resin coatings exhibited sharp increase with the extension of heat treatment time, i.e., from 7.59 MPa at room temperature to 11.78 MPa after heat treatment at 400°C for 10 h; this phenomenon occurred due to the condense of FeCoCr-resin interfaces. The complex permittivity of the coating was reduced after heat treatment, while the complex permeability increased; this gave rise to enhancement of microwave absorption and showed the working potential of the FeCoCr/silicone resin coatings at elevated temperature.

Fuel oil leaked onto asphalt pavement will damage the asphalt layer by dissolving the binder, softening the mixture and finally resulting in distress such as raveling and pitting. In the meantime, the skid resistance, high temperature stability and water stability deteriorate dramatically. Silicone resin is a fog sealing material for asphalt pavement. It forms a three-dimensional network structure with -Si-O- chains and therefore shows strong hydrophobicity and chemical stability. This paper looks into the effect of silicone resin on the fuel oil corrosion resistance of asphalt mixture. The contact angle, Cantabro test, water stability test, wheel tracking test and three-point bending test were used to investigate the road performance and the corrosion resistance under diesel and gasoline. It was found that, compared with diesel, the contact angle between gasoline and asphalt is smaller, indicating better compatibility. The gasoline corrosion decreases the properties of asphalt mixture more than that of diesel, which indicates that the compatibility is related to the corrosion effect. The results also show that silicone resin can effectively improve the adhesion, strength, water stability and high- and low-temperature performance of asphalt mixture before and after fuel oil erosion, and the improving effect on asphalt mixture after oil erosion is better. [ABSTRACT FROM AUTHOR]

Copyright of Silicone Material is the property of Silicone Material Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

All-inorganic lead halide perovskite quantum dots (PQDs) have emerged as highly promising materials for photonic and optoelectronic devices, solar cells, and photocatalysts. However, PQDs encounter instability and color separation issues because of ion diffusion. Current strategies mainly address stability in green CsPbBr 3 PQDs, with limited focus on the red-mixed halide PQDs because of their inferior stability compared with green PQDs. Our study provides a new dual-protection methodology for synthesizing high-efficiency green and red mixed-halide PQD films. Red CsPb(Br 0.4 I 0.6 ) 3 and green CsPbBr 3 PQDs are embedded with silicone resin and then incorporated with poly(methyl methacrylate) (PMMA) matrix to form red and green PQDs@silicone/PMMA films. The high photoluminescence quantum yield (PLQY) and great stability are recorded for the pure-red PQD polymer film. The ultrabright green CsPbBr 3 PQDs@silicone/PMMA film was also successfully fabricated with an outstanding PLQY beyond 94%. These films exhibited enhanced stability against thermal and environmental degradation, attributed to the dense protective layer of silicone resin and PMMA matrices by the formation of Si-halide and Pb-O bonds, thereby reducing surface defects. Theoretical calculations reveal that combining silicone resin and PMMA improves Pb-O interactions, eliminating uncoordinated Pb 2+ and enhancing PQD stability. Applied to white light-emitting diodes (WLEDs), these films demonstrated a broad color gamut of 143.4%, indicating their potential for efficient WLED backlighting.

The strong hygroscopicity of wood greatly shortens its service life. Here, a simple impregnation modification approach was used to construct superhydrophobic silicone resin coatings on wood surfaces. Briefly, with hydrofluorosilicone oil (HFSO), tetramethyl tetravinyl cyclotetrasiloxane (V4), and hydrophobic SiO2 from industrial production as raw materials, superhydrophobic wood samples (water contact angle ~160.8°, sliding angle ~3.6°) can be obtained by simply dipping the wood in the HFSO/V4/SiO2 modifier solutions. As a result, the superhydrophobic silicone resin coating constructed on the wood surface still has good water repellency after finger touching, tape peeling, and sandpaper abrasion. When the mass ratio of HFSO to V4 is 2:1, the water absorption of the resulting wood after soaking in water for 24 h is only 29.2%. Further, the resulting superhydrophobic wood shows excellent anti-fouling properties. Finally, we believe that the impregnation modification method proposed in this study can be applied to the protection of cellulose substrates. [ABSTRACT FROM AUTHOR]

In this work, we have synthesized BaTiO3 perovskite material by the hydrothermal procedure. The synthesized BaTiO3 perovskite material was characterized by XRD and FTIR analysis. The XRD study reveals high crystalline nature, and the FTIR analysis shows the presence of -OH and CH functional groups. The BaTiO3 perovskite material was mixed with silicone resin and coated over AZ31 by the doctor blade method and dried in an oven at 90 °C. The coating was cured for 2-6 h before commencing the electrochemical analysis. The coated samples were mounted with copper electrical wire and used as an anode or working electrode in 3.5% NaCl electrolyte, wherein platinum foil as the counter electrode and saturated calomel electrode (SCE) as the reference electrode. Initially, open circuit potential was recorded and preceded by electrochemical impedance (EIS) measurements. Finally, a linear sweep voltammogram or Tafel plot was recorded, and data were plotted. It is noticed that the OCP was -0.25 V (vs SCE), and corrosion current density was found around 6 x10-7 A/cm². The results reveal that perovskite-based BaTiO3 coatings demonstrated a noble shift in the corrosion potential of AZ31 alloys in the NaCl medium. The presence of silicone resin played a vital role in developing homogeneous BaTiO3 perovskite material coatings over AZ31 alloy. [ABSTRACT FROM AUTHOR]

FeSiAl soft magnetic composites (SMCs) with phosphate-silicone resin as the insulating layer were prepared by phosphating FeSiAl powder with K 3 PO 4 solution. The effects of K 3 PO 4 content on the microstructure and composition of the insulation coating were investigated. Further, the soft magnetic properties of SMCs were analyzed in detail. It is revealed that the annealed inorganic coating layer which predominantly consists of Al(PO 3) 3 , Al 2 O 3 , and P 2 O 5 exhibits a high resistivity, high temperature resistance and thin thickness, significantly reducing the eddy current loss. The outstanding magnetic properties of a power loss of 118.6 kW/m3 (100 kHz, 0.1 T) and permeability of 63.8 were achieved for this high-quality thin insulation coating. Moreover, the magnetic loss was separated into hysteresis, eddy current and excess part, and the mechanism was analyzed in detail. The reduced total loss can be ascribed to the suppression of the eddy current. The novel SMCs coating with K 3 PO 4 are particularly suitable for applications in high frequency and high DC bias situations for switching power supplies, photovoltaic inverter boost inductors and other applications. • Novel FeSiAl soft magnetic composites coated with K 3 PO 4 exhibited excellent temperature resistance. • The outstanding magnetic property with an ultra-low power loss of 118.6 kW/m3 (100 kHz, 0.1 T) was achieved. • The magnetic loss separation mechanism was analyzed in detail. [ABSTRACT FROM AUTHOR]

The silicone resin was used to modify ceramic shells for investment casting. SiC nanowires were in-situ formed by the carbothermal reduction method. The pyrolysis of silicone resin and the formation mechanism of SiC nanowires were investigated by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The results showed that the shells had the maximum sintering bending strength of 7.35 MPa when the silicone resin content and the sintering temperature were 20 wt% and 1300 °C, respectively. The phase of β-cristobalite during the transformation from amorphous SiOC to fused SiO 2 after the pyrolysis of silicone resin impacted the bending strength. In addition, the iron oxide in corundum sand was used as the catalyst in the VLS mechanism to form the ball-stick-shaped SiC nanowires at 1000 °C–1100 °C. However, the necklace-like and rod-like SiC nanowires were formed at 1200 °C–1300 °C in the VS mechanism, which replaced the VLS mechanism. [Display omitted] • The sintering strength of the modified shell was increased by 40.8% over the original shell. • The thickness of the ceramic shell at the optimal process is 6.18 mm. • The fused SiO 2 can inhibit and retard the expansion of cracks in ceramic matrix. • SiC nanowires were in-situ formed by the pyrolysis of silicone resin. • SiC nanowires were in-situ formed without catalysts by VLS and VS mechanisms. [ABSTRACT FROM AUTHOR]

In this study, amorphous FeSiCrB alloy powder, carbonyl iron powder, and high-temperature heat-resistant silicone resin were used to prepare power molding inductors, and the effects of different heat treatment procedures on the magnetic properties were investigated. Two heat treatment procedures were used. Procedure 1: Amorphous FeSiCrB alloy powder was pre-heat-treated, then mixed with carbonyl iron powder and silicone resin and uniaxially pressed to prepare power inductors. Procedure 2: A mixture of amorphous FeSiCrB alloy powder, carbonyl iron powder, and silicone resin was uniaxially pressed. After dry pressing, the compacted body was heat-treated at 500 °C. Heat treatment after compaction can reduce the internal strain caused by high-pressure compaction and promote the crystallization of superparamagnetic nano-grains simultaneously. Therefore, the compacted sample after heat treatment exhibited better magnetic properties. [ABSTRACT FROM AUTHOR]

The development of high-temperature-resistant coatings is crucial, which demands a new adhesive resin owing to harsh service conditions. In this work, the structural evolution and basic performance of three different polysilazanes with a Si–N backbone are studied, which is further compared to a typical silicone resin with a Si–O backbone. Experimental results show that polysilazanes with different structures undergo a two-step oxidation process with a residual weight higher than 77% in comparison to the one-step degradation of silicone with a weight loss higher than 47% at 800°C under flowing air atmosphere. Additionally, the decrease in thickness of polysilazane-resin coating is below 50%, while that of the silicone-resin coating is higher than 77%, which affords a crack- and defect-free morphology in polysilazanes and blistering and particle aggregation in the silicone after a temperature treatment at 800°C. Thus, our study demonstrates that polysilazanes are potential alternative choices as resin adhesives for high-temperature-resistant coatings rather than silicone-based resins, in extremely harsh conditions. [ABSTRACT FROM AUTHOR]

Copyright of Silicone Material is the property of Silicone Material Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Heat energy retention and dissipation have become key points of global smart textiles in recent years. This study describes the designing of silicon resin by using a sol–gel process, which acts as the modifying agent for siloxane substrate. The modifying agent was effectively blocked by silicon resin mixed with the ethylene or aluminum bond group, to control the molecular weight. Advanced polymer chromatography confirmed that the number average molecular weight (Mn) of silicon resin is 41,301 g mol−1, the weight average molecular weight (Mw) is 47,982 g mol−1, and the molecular weight distribution is 1.1617, which is relatively narrow. When the addition of vinyl groups is 5%, the silicone resin Mn decreases to 18,906 g mol−1 and Mw decreases to 28,641 g mol−1. When the addition of aluminum bond groups is 5%, the silicone resin Mn decreases to 17,497 g mol−1 and Mw decreases to 27,114 g mol−1. The result of thermogravimetric analysis shows that the pyrolysis temperature rises from 265.43°C to 266.17°C after the ethylene is added to the silicon resin, and the index of heat tolerance increases from 179.14°C to 191.38°C. After the addition of aluminum bond groups, the pyrolysis temperature rises from 265.43°C to 309.37°C, and the index of heat tolerance increases from 179.14°C to 193.09°C, meaning the silicone resin has higher thermal stability. [ABSTRACT FROM AUTHOR]

Copyright of Electroplating & Finishing is the property of Electroplating & Finishing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Thermo-physical properties of hollow glass microsphere (HGM) filled silicone resin are analyzed by various mathematical models to optimize the formulation for a low-density high-temperature resistant composite. The study involves analyzing effective thermal conductivity, specific heat, and density for a two-phase particulate composite system by using the most popular expressions available in the literature at various volume fractions of HGM in the silicone resin matrix. Experiments are performed to compare theoretical results with the experimental data and identified the preferred composition with a density as low as 0.39 g/cc and thermal conductivity 0.116 W/m-K. The microstructural studies by SEM are done to explain the deviation in experimental and theoretical results. FEM analysis is done to understand the heat flow phenomenon in HGM filled silicone composites. [ABSTRACT FROM AUTHOR]

A low density material coating based on silicone polymer matrix reinforced with hollow glass microspheres is developed for thermal insulation. An organo-platinum compound is added to the resin matrix to make it a fast room temperature curing coating. It has a low density in the order of 0.39−0.34 g/cc with medium Shore A hardness in the order of 60–65. The thermal stability in an inert and oxidative environment was analyzed by the TGA method. The insulative properties are investigated using an infra-red heaters test set up, which showed almost 50 % temperature reduction on the substrate compared to the non-coated substrate. The coating properties, like adhesion, impact resistance, corrosion resistance, etc., are analyzed using various bond promoters and excellent in the class of insulative coatings. The effect of various diluents on the curing is observed and then finalized the suitable diluents for spray coating. The coating forms hard silica char, which in turn protect the surface from further high temperatures. A scheme for painting the metallic and non-metallic articles is also established for ease of application to the user. [ABSTRACT FROM AUTHOR]

Abstract Background Photo-neutrons are produced at the head of the medical linear accelerators (linac) by the interaction of high-energy photons, and patients receive a whole-body-absorbed dose from these neutrons. The current study aimed to find an efficient shielding material for fast neutrons. Methods Nanoparticles (NPs) of Fe3O4 and B4C were applied in a matrix of silicone resin to design a proper shield against fast neutrons produced by the 18 MeV photon beam of a Varian 2100 C/D linac. Neutron macroscopic cross-sections for three types of samples were calculated by the Monte Carlo (MC) method and experimentally measured for neutrons of an Am-Be source. The designed shields in different concentrations were tested by MCNPX MC code, and the proper concentration was chosen for the experimental test. A shield was designed with two layers, including nano-iron oxide and a layer of nano-boron carbide for eliminating fast neutrons. Results MC simulation results with uncertainty less than 1% showed that for discrete energies and 50% nanomaterial concentration, the macroscopic cross-sections for iron oxide and boron carbide at the energy of 1 MeV were 0.36 cm− 1 and 0.32 cm− 1, respectively. For 30% nanomaterial concentration, the calculated macroscopic cross-sections for iron oxide and boron carbide shields for Am-Be spectrum equaled 0.12 cm− 1 and 0.15 cm− 1, respectively, while they are 0.15 cm− 1 and 0.18 cm− 1 for the linac spectrum. In the experiment with the Am-Be spectrum, the macroscopic cross-sections for 30% nanomaterial concentration were 0.17 ± 0.01 cm− 1 for iron oxide and 0.21 ± 0.02 cm− 1 for boron carbide. The measured transmission factors for 30% nanomaterial concentration with the Am-Be spectrum were 0.71 ± 0.01, 0.66 ± 0.02, and 0.62 ± 0.01 for the iron oxide, boron carbide, and double-layer shields, respectively. In addition, these values were 0.74, 0.69, and 0.67, respectively, for MC simulation for the linac spectrum at the same concentration and thickness of 2 cm. Conclusion Results achieved from MC simulation and experimental tests were in a satisfactory agreement. The difference between MC and measurements was in the range of 10%. Our results demonstrated that the designed double-layer shield has a superior macroscopic cross-section compared with two single-layer nanoshields and more efficiently eliminates fast photo-neutrons.

In the field of flexible electronics manufacturing, inkjet printing technology is a research hotspot, and it is key to developing low-temperature curing conductive inks that meet printing requirements and have suitable functions. Herein, methylphenylamino silicon oil (N75) and epoxy-modified silicon oil (SE35) were successfully synthesized through functional silicon monomers, and they were used to prepare silicone resin 1030H with nano SiO2. 1030H silicone resin was used as the resin binder for silver conductive ink. The silver conductive ink we prepared with 1030H has good dispersion performance with a particle size of 50–100 nm, as well as good storage stability and excellent adhesion. Additionally, the printing performance and conductivity of the silver conductive ink prepared with n,n-dimethylformamide (DMF): proprylene glycol monomethyl ether (PM) (1:1) as solvent are better than those of the silver conductive ink prepared by DMF and PM solvent. Cured at a low temperature of 160 °C, the resistivity of 1030H-Ag-82%-3 conductive ink is 6.87 × 10−6 Ω·m, and that of 1030H-Ag-92%-3 conductive ink is 0.564 × 10−6 Ω·m, so the low-temperature curing silver conductive ink has high conductivity. The low-temperature curing silver conductive ink we prepared meets the printing requirements and has potential for practical applications.

Currently, polymers and materials based on them have seriously pushed forward such basic structural materials as reinforced concrete, metal, wood. The possibilities of polymeric materials are extremely wide due to the variety of polymers and fillers, the inexhaustible variability of the compositions of composites based on them and the methods of their modification. For a long time, the main technological method for obtaining polymer composites has been mechanical mixing of a filler and a polymer matrix. Polymerization filling - chemical grafting of a catalyst or initiator to the surface of the filler and subsequent polymerization or copolymerization of monomers on these surfaces - this may open a new page in the chemistry and technology of composites. The development of the technology of composite polymer materials is currently determined by scientific research in the field of polymer materials science, since the problem of the interaction of fillers and matrices is very multifaceted. Modern person faces polymer materials not only in technology, but also in everyday practice, therefore, knowledge of the basic properties of these materials and the ability to use them correctly are gradually becoming necessary for an ever-wider circle of people. Therefore, this article provides the basic principles of obtaining and using polymer composite materials and information about the most important types of composites. The effect of porosity on the dielectric strength of a composite material based on a woven quartz filler with a pyrolysis matrix of an organosilicon binder is considered. The influence of the pyrolysis temperature during the preparation of the composite on the value of the dielectric strength is studied. It is shown that at pyrolysis temperatures above 650°C, the dielectric strength decreases by an order of magnitude and it is 3-4 kV/mm. A significant decrease in dielectric strength is due to an increase in open porosity and adsorption of air moisture on the surface of quartz fibers. [ABSTRACT FROM AUTHOR]

Copyright of Coatings & Protection / Tuceng yu Fanghu is the property of Coating & Protection Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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A facile strategy was developed to fabricate flexible polyurethane (PU) foam composites with exceptional flame retardancy. The approach involves the incorporation of graphene oxide (GO) into a silicone resin (SiR) solution, which is then deposited onto a PU foam surface via the dip-coating technique and cured. Fourier-transform infrared spectroscopy, scanning electron microscopy, and Raman spectroscopy measurements demonstrated that the SiR and GO were successfully coated onto the PU skeleton and the intrinsic porous structure of the PU foam remained intact. The effects of SiR and GO on the mechanical and thermal stability and flame retardancy of PU composites were evaluated through compression tests, thermogravimetric analysis, vertical combustion tests, and the limiting oxygen index. The measurement results revealed that the composites (PU@SiR-GO) showed superior flame retardancy and thermal and mechanical stability compared to pristine PU or PU coated with SiR alone. The mechanical and thermal stability and the flame-retardant properties of the PU composites were enhanced significantly with increasing GO content. Based on the composition, microstructure, and surface morphology of PU@SiR-GO composites before and after combustion tests, a possible flameretardance mechanism is proposed. This work provides a simple and effective strategy for fabricating flame-retardant composites with improved mechanical performance. [ABSTRACT FROM AUTHOR]

Copyright of Electroplating & Finishing is the property of Electroplating & Finishing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Based on the relevant publicly published information, the development of the silicone industry of foreign countries in 2020 and the R&D progress of the silicone products has been summarized. [ABSTRACT FROM AUTHOR]

Equipping medical devices with smart technologies holds great potential for the development of modern medical products. The development requires the identification of new integration strategies and the research of new material combinations due to the miniaturization of systems and increasing production figures. The realization of Smart Biomedical Devices requires a sufficient barrier effect (bioprotection) by appropriate encapsulation of the electronic components. Thinnest polymer coatings have proven to be suitable for conformal encapsulation. The aim of the study was to investigate the fundamental suitability of thin-film lacquers added with catalysts as coating materials for electronic systems with regard to their biological use. Due to long curing times of up to 14 days, eight different catalysts based on different chemical structures were added to the coating materials and their influence on a cytotoxic effect was investigated. A non-cytotoxic effect was observed for the organometallic catalysts based on tin, zirconium, titanium, bismuth, and tertiary amine. Most were resistant to steam sterilization. The curing time of the non-cytotoxic coatings could be significantly reduced by the addition of catalysts. The shortening of process times is an important economic aspect in the production of mass-produced Smart Biomedical Devices.

Copyright of Electroplating & Finishing is the property of Electroplating & Finishing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coatings & Protection / Tuceng yu Fanghu is the property of Coating & Protection Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Silicone Material is the property of Silicone Material Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Silicone Material is the property of Silicone Material Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Materials Science & Engineering (1673-2812) is the property of Journal of Materials Science & Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)