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Highlights The influence of filling by iron‐containing fillers on the heat release kinetics and mechanical properties of industrial unsaturated polyester resin PN‐1 is investigated experimentally. The iron ore concentrate, electrostatic precipitator dust, high alumina cement grade HAC‐1, shavings made of cast iron, fine grade sand are used as fillers. To improve the strength characteristics of polyester resin composites the small amount (0.2–1.0 wt%) of organosilicon additives such as synthetic silicone rubber, tris(trimethylsiloxy) phenylsilane, octamethyl cyclotetrasiloxane are used. The heat release kinetics is studied for different ratios between accelerator (cobalt naphthenate) and initiator (cyclohexanone peroxide). The time to reach the maximum temperature of the heat release is significantly reduced when a large amount of iron ore concentrate is used as filler. The temperature of maximum heat release decreases and the time to reach it increases when adding electrostatic precipitator dust in small amount of 5 wt% to the high filled by iron ore concentrate (295 wt%) composite system. The optimum in strength indicators associated with the ratio of different fractions in systems consisting of two fillers of different properties and granulometric composition is found. The highest values of compressive strength in the cement–iron ore concentrate and sand–iron ore concentrate systems are observed. An increase in the strength characteristics of composites by 15%–20% with organosilicon additive introduction is observed. The addition of the silicone rubber increases the strength properties of samples the most among all additives considered. Effect of filling by iron‐containing fillers on the heat release kinetics and mechanical properties of polyester resin is found. The time to reach the maximum temperature of the heat release is significantly reduced when the resin is filled by a large amount of iron ore concentrate. The temperature of maximum heat release decreases when the electrostatic precipitator dust in small amount is added to the high filled by iron ore concentrate. An increase in the strength characteristics of composites by 15–20% with introduction of organosilicon additives is observed. [ABSTRACT FROM AUTHOR]

Aiming at settling the critical problems of ecological and environmental safety caused by traditional halogen-containing and phosphorus-containing flame-retardant system, this paper has fabricated a transition metal manganese ion (Mn2+) loaded diatomite (Mn@DE) via a simple chemical modification process, which can be employed as raising the flame retardancy of silicone rubber (SR). Compared with traditional flame retardants, the unique lamellar shielding ability and Mn-enhanced catalytic charring ability from designed mineral-based flame retardants are conductive to upgrading the flame-retardant level of silicone rubber/Mn-modified diatomite (SR/Mn@DE) composites. The results demonstrate that when the amount of Mn@DE reaches 30 phr in the composites, the limiting oxygen index (LOI) and vertical combustion tests of SR/30 phr Mn@DE can reach 27.3% and UL-94 V-0 ratings, respectively. Simultaneously, the reduction for peak heat release rate (PHRR) and total heat rate (THR) of SR/Mn@DE can achieve 55.3% and 66.1%, revealing that the fire hazard of SR has been effectively decreased. Thermogravimetric analysis (TGA) has enlightened that the introduction of Mn onto diatomite can effectively reinforce the thermal stability and char-forming ability of SR composites. Through the systematic analysis for combustion residues, the condensed flame-retardant mechanism of SR/Mn@DE via restraining the heat transfer and fuel feedback can be primarily inferred. Therefore, this paper have provided a fast and practical flame-retardant strategy in order to discarding the halogen-/phosphorus-containing flame retardants, which will open up the key problem of limited application for SR composites in more fields. [ABSTRACT FROM AUTHOR]

Inspired by the natural thermal charring capacity of lacquer tree bark, a novel halogen-free, bio-based and two-component synergistic flame retardant system has been constructed by introducing transition metal (Fe3+)-modified tannic acid (TA) as char source and ammonium polyphosphate (APP) as acid source, which was employed for overcoming the severe flammability problem for silicone rubber (SR). By systematically investigating the effect of APP/TA@Fe system on the flame retardancy of SR composites, it has been found that when 40 mass% APP and TA@Fe in a ratio of 3:1 are added, the limited oxygen index (LOI) and vertical combustion tests of SR composites can reach 30% and UL-94 V-0 rating with a rapid self-extinguishing capacity. Through the comprehensive analysis of the residues of SR composites after complete burning, a gas/condensed flame retardant mechanism is primarily proposed in detail. Among these, the ammonia and water vapor released by the decomposition of APP and TA@Fe during combustion can dilute the combustible gases and tannic acid will act via the free radicals scavenging ability. Besides, the continuous, intumescent and dense charring residues from the thermal interaction between APP and TA will exert a prominent role in restricting the heat/mass exchange process and inhibiting the SR matrix from further flame attacking. Surprisingly, the mechanical strength of SR system is attained even if the combination of APP and TA@Fe is blended. Consequently, this article has developed a bionic, eco-friendly and effective approach to settle the flammability problem of SR and broaden their applications in the fields of construction and decoration materials. [ABSTRACT FROM AUTHOR]

The combined insulation interface of a high-voltage cable and accessories is the weakest part of a cable system. In this paper, the parameters of the dielectric constant, thermal conductivity, and elastic modulus of cross-linked polyethylene (XLPE) and silicone rubber (SIR) are obtained experimentally. On this basis, the model of a specific type of 110 kV cable and prefabricated insulation joint is established. A simulation of the electric–thermal–stress coupling field in the presence of typical defects in the main insulation–inner semi-conductive (SEMI) shielding layer (XLPE/SEMI interface) and the main insulation–silicone rubber insulation layer (XLPE/SIR interface) is studied. The simulation results show that at the XLPE/SIR interface, the electric field distortion caused by bubble defects reached 20.17 kV/mm, and the temperature rose to 56.15 °C. The effect of air-gap defects on the interface is similar to that of bubble defects. In addition, the semi-conductive impurity defects induced an increase in temperature to 56.82 °C and an increase in stress to 0.32 MPa. At the XLPE/SEMI interface, the electric field distortion induced by bubble defects was 19.98 kV/mm, and the temperature rose to 61.72 °C. The electric field distortion caused by metallic and semi-conductive defects was 8.44 kV/mm and 8.64 kV/mm, respectively. This study serves as a reference for the fault analysis and the operation and maintenance of cable accessories. [ABSTRACT FROM AUTHOR]

Silicone rubber (SR), as one kind of highly valuable rubber material, has been widely used in many fields, e.g., construction, transportation, the electronics industry, automobiles, aviation, and biology, owing to its attractive properties, including high- and low-temperature resistance, weathering resistance, chemical stability, and electrical isolation, as well as transparency. Unfortunately, the inherent flammability of SR largely restricts its practical application in many fields that have high standard requirements for flame retardancy. Throughout the last decade, a series of flame-retardant strategies have been adopted which enhance the flame retardancy of SR and even enhance its other key properties, such as mechanical properties and thermal stability. This comprehensive review systematically reviewed the recent research advances in flame-retarded SR materials and summarized and introduced the up-to-date design of different types of flame retardants and their effects on flame-retardant properties and other performances of SR. In addition, the related flame-retardant mechanisms of the as-prepared flame-retardant SR materials are analyzed and presented. Moreover, key challenges associated with these various types of FRs are discussed, and future development directions are also proposed. [ABSTRACT FROM AUTHOR]

The presence of oil-contaminated water due to oil spill disasters or improper industrial waste dumping is now a worldwide danger to both human health and the sustainability of the environment.The use of superhydrophobic materials has attracted considerable attention in the field of oil-water separation, owing to the increasing demand for effective and economical oil-water separation techniques.A new, easy, and inexpensive flame treatment method was used to make a nanocomposite (CuO-SiO2) in order to improve its hierarchical structure (micro-nano).The anodisation process produced copper oxide (CuO) nanostructures (NSs) on a copper mesh. Subsequently, the nanostructures were modified by dip coating with a solution of room-temperature vulcanised silicone rubber (RTV-SR).The coated mesh demonstrated remarkable characteristics of superhydrophobicity and superoleophilicity, with a water contact angle (WCA) of (160 ± 1°) and an oil contact angle (OCA) of (0°), as determined during the measurement of the surface's wetability. The coated mesh surface was characterised using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and energy dispersive spectroscopy (EDS).The successful separation of kerosene-water and diesel oil-water mixtures is accomplished by using a coated mesh in a simple filtration procedure. Furthermore, it has the capability to separate oils with a high efficiency of (99.8%) for kerosene and (87%) for diesel oil. It also has flux values of (7352.9 L.m-2.h-1) for kerosene and (6112.9 L/m2.h) for diesel. [ABSTRACT FROM AUTHOR]

Lightweight, electrically insulating and high thermally conductive materials are highly desirable in electronic and power systems because they can effectively transfer heat and avoid temperature rise of the equipment and devices, thus guaranteeing normal operation. In this work, silica-coated spherical boron nitride (SiO2@s-BN) was successfully fabricated and prepared as a thermally conductive composite by blending with silicone rubber (SR). Due to the modulus matching, SiO2@BN could decrease the thermal resistance between the SR matrices and the thermally conductive fillers, thus achieving higher thermal conductivity compared with the original BN at the same filler loading. When the SR composite is filled with 40 wt% SiO2@BN, the thermal conductivity can reach 1.2 W m−1 K−1, which is 16.5% higher than that of the 40 wt% s-BN/SR composite. Simultaneously, the 40 wt% SiO2@BN/SR composite material not only exhibits excellent dielectric, thermal, and mechanical properties but also demonstrates outstanding processability, maintaining a low precursor viscosity of only 14.5 Pa·s. Overall, this work provides a novel strategy for developing high thermally conductive SR composites with good processability. [ABSTRACT FROM AUTHOR]

[Display omitted] Replicating the tactile sensing mechanisms, conformity, and feel of real skin is essential for next-generation human–machine interfaces. However, producing tissue-like multilayered geometries and integrating them as e-skin systems requires simplifying and standardizing their manufacture. Here, we present a scalable and cost-effective cure-on-demand strategy for 3D printing nanocomposite silicone rubbers and integrating them into complex soft structures with 1200 % enhanced pressure-strain sensitivity. By utilizing a controlled in-situ mixing of catalyst-cured silicones and shear-driven alignment of carbon nanofibers (CNF), we construct percolated networks with conductivities up to 130 S m−1 layer-by-layer. We investigate the influence of ink composition, printing parameters, geometrical design, and material density on the mechanical properties, stretchability, sensitivity, and antimicrobial activity of 3D printed piezoresistive sensors and build skin-like interfaces that detect minimal deformations like human physiological signs. This customizable, biocompatible, and robust e-skin holds promise for cost-effective integration in rehabilitation medicine, smart robotics applications, and extended reality (XR) interactive experiences. [ABSTRACT FROM AUTHOR]

The heat aging resistance of a peroxide-cured silicone rubber (VMQ) in the temperature range from 75 to 225 °C was investigated. Activation energies for the degradation process were calculated in order to understand the durability and lifetime of the rubber. The hardness, tensile stress at 10% elongation, and chemical cross-link density measured by solvent swell and double-quantum nuclear magnetic resonance increase as a function of thermal aging. The increase is due to the prevalence of cross-linking reactions over chain scission events which was confirmed by FTIR analysis. The unaged monomodal cross-link distribution becomes more heterogeneous with heat aging as its distribution significantly widens toward higher cross-link densities. Calculated activation energies for the heat-induced degradation process were between 70 and 101 kJ/mol. Activation energies depended on the experimental test used to probe the system. The FTIR analysis confirmed the loss of –CH bonds and gain of Si–O–Si linkages during thermal aging. Oxidative products were extracted and characterized from the degraded VMQ. Aerobic and non-aerobic degradation mechanisms have been proposed to explain the presence of cross-linking and chain scission reactions. Given the lack of data change during low-temperature aging, the results are suitable for use to predict the performance of VMQ in applications between 100 and 225 °C. [ABSTRACT FROM AUTHOR]

Liquid silicone rubber (LSR) is characterized by a wide range of advantageous properties and is therefore used in many branches and industries. However, the material is difficult to recycle due to the non‐reversible cross‐linking reaction. A promising approach to recycle the already cross‐linked (post‐industrial) waste is the mechanical recycling of LSR via grinding and addition of the powder as filler in virgin material. This research focused on the processing of such LSR‐powder‐compounds via injection molding and the influence of the powder content on mechanical properties. Compounds of virgin LSR and ambient ground powder were prepared and injection molded. Both the processability and the mechanical properties were analyzed. Compounds of up to 40 wt% powder content could be processed with standard injection molding machine equipment without any noticeable issues. The results show a similar compression set for the virgin as for the recycled compounds. Hardness decreases slightly but constantly. Tensile strength and elongation at break are at similar levels for all powder added compounds and drop only by 16.6% and 12.6% compared with the virgin LSR. The results are promising and should be the basis for further and more detailed investigations to industrialize the mechanical recycling of LSR. Highlights: Processing on standard injection molding machine with standard parameters.Up to 40 wt% recycled silicone powder content.Using recycled silicone particles has no effect on compression set.Tensile strength and elongation at break decrease only by 16.6% and 12.6%. [ABSTRACT FROM AUTHOR]

The vibrations generated in the two-wheeled vehicles like motorcycles due to road irregularities such as cracks, potholes, and bumps on the road cause discomfort for the rider as well as the pillion. These vibrations are reported to cause lower back pains, musculoskeletal effects, fatigue, and long-term health issues. Particularly, electric two-wheelers are more susceptible to these vibrations caused by the road and need attention. This paper presents an innovative technique for the reduction of vibrations at prominent locations in the electric two-wheeler to improve the rider's comfort. All measured accelerations are about vertical direction (along z-axis as per ISO 2631-1 standard). Passive and Semi-active damping treatments namely, Room temperature vulcanizing Silicone rubber and Magnetorheological elastomer (MRE) were applied on the test vehicle at strategic locations of vibration. Both were compared for their effectiveness in reducing the vibrations. Results showed that MRE based damping technique proved better vibration isolation at the strategic locations. The weighted root mean square acceleration as well as vibration dose values were found to decrease with the help of damping treatments thus improving the rider's overall comfort level. [ABSTRACT FROM AUTHOR]

The diverse applications of magnetorheological elastomer (MRE) drive efforts to understand consistent performance and resistance to failure. Stress relaxation can lead to molecular chain deterioration, degradation in stiffness and rheological properties, and ultimately affect the life cycle of MRE. However, quantifying the energy and molecular dynamics during stress relaxation is challenging due to the difficulty of obtaining atomic-level insights experimentally. This study employs molecular dynamics (MD) simulation to elucidate the stress relaxation in MRE during constant strain. Magnetorheological elastomer models incorporating silicone rubber filled with varying magnetic iron particles (50–80 wt%) were constructed. Experimental results from an oscillatory shear rheometer showed the linear viscoelastic region of MRE to be within 0.001–0.01% strain. The simulation results indicated that stress relaxation has occurred, with stored energies decreased by 8.63–52.7% in all MRE models. Monitoring changes in energy components, the highest final stored energy (12,045 kJ) of the MRE model with 80 wt% Fe particles was primarily attributed to stronger intramolecular and intermolecular interactions, revealed by higher potential energy (3262 kJ) and van der Waals energy (− 2717.29 kJ). Stress relaxation also altered the molecular dynamics of this MRE model as evidenced by a decrease in kinetic energy (9362 kJ) and mean square displacement value (20,318 Å2). The MD simulation provides a promising quantitative tool for elucidating stress relaxation, preventing material failure and offering insights for the design of MRE in the nanotechnology industry. [ABSTRACT FROM AUTHOR]

Copyright of China Plastics / Zhongguo Suliao is the property of Journal Office of CHINA PLASTICS 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.)

To enhance the low‐temperature toughness and resistance of the engineering plastic polyamide PA12, this study introduces novel PA12/MVQ@POE‐g‐MAH ternary composites using a two‐step process and dynamic curing. Analytical results indicate that incorporating MVQ@POE‐g‐MAH into the PA12 matrix markedly enhances its toughness and heat resistance. As the MVQ@POE‐g‐MAH content increases, the elongation at break of PA12 composites significantly expands from 52.83% to 204.69%, and the notch impact strength escalates from 8.69 to 74.34 kJ m−2. In addition, the brittleness temperature of PA12 decreases from −59.5 to −67.0 °C. Experimental findings confirm that POE‐g‐MAH is dispersed at the interface between MVQ and PA12, creating an encapsulated structure of MVQ@POE‐g‐MAH. This enhancement significantly broadens the potential applications of PA12 by improving its toughness, and resistance to both low and high temperatures, as well as impact endurance. [ABSTRACT FROM AUTHOR]

Three-dimensional-printed silicone rubber foams, with their designable and highly ordered pore structures, have shown exceptional potential for engineering applications, particularly in areas requiring energy absorption and cushioning. However, optimizing the mechanical properties of these foams through structural design remains a significant challenge. This study addresses this challenge by formulating the research question: How do different 3D-printed topologies and printing parameters affect the mechanical properties of silicone rubber foams, and how can we design a novel topological structure? To answer this, we explored the mechanical behavior of two common structures–simple cubic (SC) and face-centered tetragonal (FCT)–by varying printing parameters such as filament spacing, filament diameter, and layer height. Furthermore, we proposed a novel two-level 3D-printed structure, combining SC and FCT configurations to enhance performance. The results demonstrated that the two-level SC-SC structure exhibited a specific energy absorption of 8.2 to 21.0 times greater than the SC structure and 2.3 to 7.2 times greater than the FCT structure. In conclusion, this study provides new insights into the design of 3D-printed silicone rubber foams, offering a promising approach to developing advanced cushioning materials with superior energy absorption capabilities. [ABSTRACT FROM AUTHOR]

The material parameters required to describe material behavior can change with the age of the components due to chemical and physical aging processes. The finite element method (FEM) is a tool for designing components for later use. The aim of this study is to correlate the change in the mechanical properties of silicone elastomers from standard tests over a longer period of time with the parameters of the Mooney–Rivlin model. To date, there are no publications on the development of the Mooney–Rivlin parameters of silicone elastomers over a storage period. For this purpose, the Shore A hardness, rebound elasticity, compression set and tensile properties were investigated over an aging period of approx. 200 days on two liquid silicone rubbers (LSRs) and one room-temperature-vulcanizing (RTV) silicone rubber. Depending on the silicone elastomer used, different trends in the characteristic values can be observed over the storage period. In general, increases in the Shore A hardness, rebound resilience and stress at a 100% strain with a decrease in the compression set can be determined. In addition to standard tensile tests, the material's multiaxial behavior under tension was probed, and it was found that the similarly stress at a 100% strain increased. Finite element simulations verified the standard tensile test and corresponding Mooney–Rivlin model parameters. These parameters from the uniaxial tensile were validated in the multiaxial behavior, and the model's accuracy in representing material properties and the influence of aging on the FEM simulation were affirmed. [ABSTRACT FROM AUTHOR]

The insulation of high-voltage direct-current (HVDC) cables experiences a short period of voltage polarity reversal when the power flow is adjusted, leading to sever field distortion in this situation. Consequently, improving the insulation performance of the composite insulation structure in these cables has become an urgent challenge. In this paper, SiC-SR (silicone rubber) and TiO2-SR nanocomposites were chosen for fabricating HVDC cable accessories. These nanocomposites were prepared using the solution blending method, and an electro-acoustic pulse (PEA) space charge test platform was established to explore the electron transfer mechanism. The space charge characteristics and field strength distribution of a double-layer dielectric composed of cross-linked polyethylene (XLPE) and nano-composite SR at different concentrations were studied during voltage polarity reversal. Additionally, a self-built breakdown platform for flake samples was established to explore the effect of the nanoparticle doping concentration on the breakdown field strength of double-layer composite media under polarity reversal. Therefore, a correlation was established between the micro electron transfer process and the macro electrical properties of polymers (XLPE/SR). The results show that optimal concentrations of nano-SiC and TiO2 particles introduce deep traps in the SR matrix, significantly inhibiting charge accumulation and electric field distortion at the interface, thereby effectively improving the dielectric strength of the double-layer polymers (XLPE/SR). [ABSTRACT FROM AUTHOR]

Associating molecular structure and mechanical properties is important for silicone rubber design. Although silicone rubbers are widely used due to their odourless, non-toxic, and high- and low-temperature resistance advantages, their application and development are still limited by their poor mechanical properties. The mechanical properties of silicone rubbers can be regulated by designing the cross-link density and cross-linking structure, and altering the molar contents of vinyl in the side groups of methyl vinyl silicone rubber (MVQ) leads to different cross-linking structures and cross-linking densities in the vulcanized rubber. Therefore, this study investigated the differences in molecular parameters and molecular chain structures of unprocessed MVQ rubbers with different vinyl contents. The results showed that MVQ rubbers with high vinyl contents were branched polymers, better facilitating the cross-linking reaction than MVQ rubbers with low vinyl contents. In addition, silicone rubbers with different vinyl contents were co-cross-linked to introduce an inhomogeneous cross-linked network in the silicone rubber to improve its mechanical properties. The cross-linked network properties were analysed by the Flory–Rehner model and Mooney–Rivlin plots, and it was found that the long chains in the sparsely cross-linked domains of the network favoured high elongation at break and the short chains in the densely cross-linked domains contributed to high modulus, which could satisfy the functions of reinforcing and toughening the rubber materials at the same time. It was also found by analysing the filler network and aggregate morphology that the inhomogeneous cross-linked network led to an improvement in the dispersion of silica in the rubber and a significant improvement in the mechanical properties of silicone rubber. [ABSTRACT FROM AUTHOR]

Silicone rubber is a good candidate as a carrier of small molecules in such applications as drug, fragrance and semiochemical delivery. When one matrix is loaded, the molecular interactions between the molecules and the matrix may affect their release rates. For this reason, it is important to investigate the effects of molecular interactions on release to better develop delivery systems with desirable release rates. In this study, the mass transfer and diffusion coefficients of three model molecules (i.e., octanol, octyl acetate, and octyl butyrate) were determined by monitoring their release from silicone rubber sheets loaded using headspace gas chromatography–mass spectrometry. Differential scanning calorimetry was used to characterize the plasticizing effects and Fourier transform infrared spectroscopy was used to characterize the molecular interactions. It was found that the release of octanol conformed to the Fickian diffusion pattern at 1 wt% initial concentration but deviated as the concentration increased due to hydrogen bonding between octanol and the silanol group of the silica filler. When two small molecules were released simultaneously, the effects of one molecule on the diffusion coefficient of the other differed, a result explained by the competing effects of plasticizing and hydrogen bonding. [ABSTRACT FROM AUTHOR]

This paper considers the design, manufacture, and testing of a prototype "soft–stiff" worm-inspired robot referred to herein, as the PneumaticallyActuated PeristaLtic Advancing Modular (PALAM) robot. The robot has a modular structure, mimicking the segmented nature of earthworms, and each segment is individually actuated by a set of three pneumatic artificial muscles (PAMs). The PAMs contract when inflated by pressurised air, generating a pulling force and fulfilling the role of biological muscles in the robot. The PAMs are made from the elastomer silicone rubber, which affords the robot flexibility and enables a wide range of real-life applications. A control-system is designed which can inflate any PAM on demand, and hence replicate the peristaltic motion of earthworms in the PALAM robot. Finally, this paper discusses a successful, low-cost, and widely accessible approach for the manufacture of the PAMs utilised herein. The PAMs can be scaled dimensionally and made from different materials with varying mechanical properties and behaviours, meaning that they are suitable for use in a wide range of robotics applications. [ABSTRACT FROM AUTHOR]

WO3 and silicone rubber (SR)-based gasochromic composites were fabricated to detect hydrogen leaks at room temperature. WO3 rod-like nanostructures were uniformly distributed in the SR matrix, with a particle size of 60–100 nm. The hydrogen permeability of these composites reached 1.77 cm3·cm/cm2·s·cmHg. At a 10% hydrogen concentration, the visible light reflectance of the composite decreased 49% during about 40 s, with a color change rate of 6.4% s−1. Moreover, the composite detected hydrogen concentrations as low as 0.1%. And a color scale was obtained for easily assessing hydrogen concentrations in the environment based on the color of composites. Finally, the composite materials as disposable sensors underwent testing at several Sinopec hydrogen refueling stations. [ABSTRACT FROM AUTHOR]

To enhance mechanical, adhesive, and thermal properties of Room Temperature Vulcanized (RTV) silicone rubber, a silicon-containing polyurethane/epoxy resin modifier (ESiPU) was developed. A three-phase system of polyurethane/epoxy resin/silicone rubber was prepared through blending, modification, and co-curing. FT-IR and 1H-NMR were employed to characterize the chemical structure of ESiPU. Microscopic analysis revealed improved compatibility between modified epoxy resin and silicone rubber. Mechanical testing showed significant enhancements in tensile strength, elongation at break, and adhesive strength, with RTV-20phr exhibiting increases of 236, 266, and 259%, respectively. Thermogravimetric analysis indicated higher initial decomposition temperature compared to pure RTV. At the same time, the char residue at 800 °C increased to 8.67%. TG-IR analysis demonstrated ESiPU's ability to delay thermal degradation. Contact angle test confirmed improved hydrophobicity. Overall, the developed silicone rubber system exhibits promising mechanical and thermal properties, suggesting potential for aerospace heat protection applications. [ABSTRACT FROM AUTHOR]

In practical applications, polyurethane (PU) foam must be rigid to meet the demands of various industries and provide comfort and protection in everyday life. PU foam components are extensively used in structural foam, thermal insulation, decorative panels, packaging, imitation wood, and floral foam, as well as in models and prototypes. Conventional technology for producing PU foam parts often leads to defects such as deformation, short shots, entrapped air, warpage, flash, micro-bubbles, weld lines, and voids. Therefore, the development of rigid PU foam parts has become a crucial research focus in the industry. This study proposes an innovative manufacturing process for producing rigid PU foam parts using silicone rubber molds (SRMs). The deformation of the silicone rubber mold can be predicted based on its wall thickness, following a trend equation with a correlation coefficient of 0.9951. The volume of the PU foam part can also be predicted by the weight of the PU foaming agent, as indicated by a trend equation with a correlation coefficient of 0.9824. The optimal weight ratio of the foaming agent to water, yielding the highest surface hardness, was found to be 5:1. The surface hardness of the PU foam part can also be predicted based on the weight of the water used, according to a proposed prediction equation with a correlation coefficient of 0.7517. The average surface hardness of the fabricated PU foam part has a Shore O hardness value of approximately 75. Foam parts made with 1.5 g of water added to 15 g of a foaming agent have the fewest internal pores, resulting in the densest interior. PU foam parts exhibit excellent mechanical properties when 3 g of water is added to the PU foaming agent, as evidenced by their surface hardness and compressive strength. Using rigid PU foam parts as a backing material in the proposed method can reduce rapid tool production costs by about 62%. Finally, an innovative manufacturing process for creating large SRMs using rigid PU foam parts as backing material is demonstrated. [ABSTRACT FROM AUTHOR]

Liquid‐metal embedded elastomers (LMEEs) have been demonstrated to show a variety of excellent properties, including high toughness, dielectric constant, and thermal conductivity, with applications across soft electronics and robotics. However, within this scope of use cases, operation in extreme environments – such as high‐temperature conditions – may lead to material degradation. While prior works highlight the functionality of LMEEs, there is limited insight on the thermal stability of these soft materials and how the effects of liquid metal (LM) inclusions depend on temperature. Here, the effects on thermal stability, including mechanical and electrical properties, of LMEEs are introduced. Effects are characterized for both fluoroelastomer and other elastomer‐based composites at temperature exposures up to 325 °C, where it is shown that embedding LM can offer improvements in thermo‐mechanical stability. Compared to elastomer like silicone rubber that has been previously used for LMEEs, a fluoroelastomer matrix offers a higher dielectric constant and significant improvement in thermo‐mechanical stability without sacrificing room temperature properties, such as thermal conductivity and modulus. Fluoroelastomer‐LM composites offer a promising soft, multi‐functional material for high‐temperature applications, which is demonstrated here with a printed, soft heat sink and an endoscopic sensor capable of wireless sensing of high temperatures. [ABSTRACT FROM AUTHOR]

In this paper, the silicone rubber (SR)/thermoplastic polyurethane (TPU) composites and its compatibilizers were studied by molecule dynamics simulation and experiment. Three compatibilizers, fluorosilicone rubber (FSR), dendritic hydroxyl-terminated silicone oil (DHSO), and fluorinated modified tetraethyl orthosilicate grafted silicone rubber (FTEOS-g-SR) were introduced into the SR/TPU composites. The simulation results showed that the cohesion density of pure SR was 3.072 × 108 J/m3, the solubility parameter was 17.504 (J/cm3)0.5, the Young's modulus was 4.0139 GPa, the shear modulus was 1.4493 GPa, and the bulk modulus was 5.8061 GPa. Moreover, the cohesion density of SR/TPU/FSR and SR/TPU/DHSO increased to 4.693 × 108 and 3.459 × 108 J/m3, solubility parameter increased to 21.662 and 18.597 (J/cm3)0.5, the Young's modulus increased to 6.6399 and 6.0020 GPa, shear modulus increased to 2.4377 and 2.2060 GPa, and bulk modulus increased to 8.0148 and 7.1653 GPa, respectively. However, the cohesion density, solubility, and young's modulus of SR/TPU/FTEOS-g-SR decreased to 2.617 × 108 J/m3, 16.174 (J/cm3)0.5, 3.872 GPa, 1.7510 Gpa, and 1.6365 GPa. These results demonstrated that both FSR and DHSO can improve the mechanical properties of the SR/TPU composites, while the FTEOS-g-SR reduced their mechanical properties. The compatibility and mechanical properties of SR/TPU composites modified by FSR and DHSO were verified and compared. The factors such as blending temperature, blending ratio, and TPU types of SR/TPU composites were considered. Compared to composites cured at 185 °C, those cured at 175 °C exhibited better mechanical properties. The dynamically vulcanized SR/TPU (3:7, mass ratio) materials showed superior tensile strength and elongation at break when compared to the SR/TPU (5:5, mass ratio) composites. Moreover, the polyether type of TPU was found to be more favorable than the polyester type for obtaining a blended composite with good tensile properties. The experimental results demonstrated that both compatibilizers contributed to improving the mechanical properties of the composites to a certain extent. The scanning electron microscope (SEM) test revealed that FSR enhanced the dispersion of SR in the TPU matrix. Additionally, charge distribution simulation analysis indicated the presence of abundant intermolecular hydrogen bonds between FSR and TPU, which played a significant role in the excellent compatibility and mechanical properties observed in this blend system. [ABSTRACT FROM AUTHOR]

UV ray is an unavoidable environmental factor in the operation of outdoor cable accessories, which is easy to cause the cable accessories flashover and breakdown faults. In this paper, the changes of insulation properties of silicone rubber (SiR) after UV radiation treatment were studied from the aspects of microstructure, dielectric properties, surface properties and discharge properties. Combined with the analysis of molecular chain damage and surface trap, the influence mechanism of UV radiation on the insulation properties of SiR was revealed. The experimental results show that the dielectric constant of SiR after UV radiation treatment first decreases and then increases, it decreases to 3.06 at 240 h and increases to 3.93 at 1000 h. UV radiation can reduce the surface resistance of SiR, it decreases by 48% after 1000 h radiation. With the extension of UV radiation time, the surface trap level corresponding to the peak of the trap density is about 0.95 eV, the trap density decreases to 2.32 × 1022 eV−1 m−3 at 240 h. Short-term UV radiation can promote the secondary cross-linking of SiR, resulting in the increase of flashover voltage from 6.32 to 7.64 kV. Long-term radiation can destroy the molecular chain structure, resulting in a slight decrease in the flashover voltage. With the extension of UV radiation time, the breakdown strength decreases by about 14% at 1000 h. This work has guiding significance for the radiation performance and life evaluation of cable accessories. [ABSTRACT FROM AUTHOR]

Copyright of China Rubber Industry is the property of Editorial Office of China Rubber Industry 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 Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group 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.)

In this study, blends of silicone rubber (SR) and benzoxazine (BZ) were prepared accompanied by ethylene propylene diene monomer grafted with maleic anhydride (EPDM‐g‐MA) as the compatibilizing agent. A total of 3 phr MA grafted EPDM showed the most favorable grafting efficiency and relatively lower gel content. Results showed that 8 phr (EPDM‐g‐MA) was the optimal compatibilizer content in the 85/15 SR/BZ blend, which was used for further studies. Morphological studies proved that the greatest reduction in the dispersed droplet size (from 1.32 to 0.23 μm) occurred at this optimal compatibilizer loading (8 phr). The lowest difference between the glass transition temperatures of the blend components was observed at the 8 phr compatibilizer content, which was confirmed by DMTA. The mechanical and curing characteristics of compatibilized and uncompatibilized blends were also studied. The results evinced that the tensile strength of the compatibilized samples was higher than that of the uncompatibilized blends. Thermal studies on the 85/15 SR/BZ blend and nanocomposites containing 1, 3, and 5 phr polyhedral oligomeric silsesquioxane (POSS) nanoparticles revealed that the thermal stability of nanocomposites containing 1 and 3 phr POSS was superior to that of the nanocomposite with 5 phr POSS. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Materials Engineering / Cailiao Gongcheng is the property of Journal of Materials 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.)

Strategies for synthesis and processing of silicone rubber materials in three-dimensional (3D) structures are of significant interest based on their exceptional potential in many applications including flexible electronics and biomedical devices. Here, we present a synthetic approach of crosslinked polydimethylsiloxane (PDMS) exhibiting dynamic siloxane bond exchange for sufficient stress relaxation capability to enable versatile processabilities including reprocessing, remolding, self-healing, and hot-melt extrusion 3D printing. Considering the significant potential of recyclable silicone materials and their 3D structures, presented approaches enabled by dynamic exchangeable PDMS can provide a new pathway to replace conventional unrecyclable silicone used in diverse industrial sectors. [ABSTRACT FROM AUTHOR]

This article shows three different water‐based physical blowing agents for liquid silicone rubber (LSR) in terms of physical, mechanical, and morphological properties depending on the manufacturing parameters and amounts of blowing agents. The compositions consist of common LSRs added with pure water, water–silicone oil emulsion, and aqueous silicone. The foaming process is initiated in an injection molding process. By subvolumetrically filling the mold, it is possible to foam the LSR during the injection molding process. This publication aims to compare different, water‐based blowing agents for LSR in the injection molding process. The results show that for all foams porosities between 0.25 and 0.4 are possible. An analysis of the foam structure shows that the aqueous silicone produces a significantly more homogeneous structure than the other two blowing agents. In addition, the mechanical properties are analyzed. For this purpose, tensile tests are carried out and the Shore hardness is determined. The elasticity and mechanical properties decrease slightly. The specific tensile strength also shows a small decrease, although this may be due to either the gradient of the foam structure or chemical reactions between the blowing agents and the LSR. [ABSTRACT FROM AUTHOR]

AbstractDrawing on the driving mechanism of biological muscles and combining the nonlinear hyperelastic characteristics of silicone rubber, a multi-degree-of-freedom pneumatic soft bionic actuator is designed, which can be used as the executing mechanism for soft robots and robotic arms. Using response surface analysis and numerical simulation algorithms, the optimal combination of structural dimensions parameters is determined with the maximum bending and torsion angles output by the actuator as the optimization objectives. Based on the idea of flexible mechanism Piecewise Constant Curvature (PCC) modeling, the kinematics equation of the actuator is derived. Analyze the equivalent motion structure of the actuator and establish a dynamic model of the actuator based on the Lagrange method. The physical model of the actuator is manufactured using rapid prototyping technology. Finally, experimental testing and analysis are conducted on the physical model to obtain the motion and dynamic characteristics curves and empirical formulas of the actuator, which are compared with theoretical and simulation results to verify that the pneumatic soft bionic actuator is feasible and effective. The above research methods, processes, and results can provide reference and inspiration for the research and implementation of pneumatic and hydraulic soft robots and gripping actuators for soft robotic arms. [ABSTRACT FROM AUTHOR]

To develop a type of nanocomposite with high barrier properties for the solid propellant insulation layer, functionalized magnetic graphene oxide (FMGO) was prepared using the ultrasound-assisted coprecipitation method. The structure of FMGO was characterized by X-ray diffraction, Raman spectroscopy, and X-ray photoelectron spectroscopy. To attain a structured orientation within the silicone rubber (SiR) matrix and enhance the barrier properties of the SiR matrix insulation layer, FMGO nanofillers were incorporated into SiR and subjected to a rotating magnetic field (100 mT). Subsequently, a comprehensive characterization of the morphology of the ordered FMGO/SiR composites was conducted. Experimental results showed that the ordered FMGO/SiR composites with a rotating magnetic field exhibited improved barrier properties, achieving a 46.4% reduction in oxygen permeability and a 25.1% reduction in dioctyl sebacate migration equilibrium concentration compared to random FMGO/SiR composites. The barrier property of the SiR matrix is effectively improved due to the ordered alignment of FMGO flakes, which act as a physical barrier. This work successfully aligned FMGO within the polymer matrix in a controllable way and finally prepared highly ordered FMGO/SiR composites equipped with notable barrier properties. [ABSTRACT FROM AUTHOR]

Purpose: Hepatocellular carcinoma (HCC) is one of the most common types of liver cancer that could potentially be surrounded by healthy arteries or veins that a surgeon would have to avoid during treatment. A realistic 3D liver model is an unmet need for HCC preoperative planning. Methods: This paper presents a method to create a soft phantom model of the human liver with the help of a 3D-printed mold, silicone, ballistic gel, and a blender. Results: For silicone, the elastic modulus of seven different ratios of base silicone and silicone hardener are tested; while for ballistic gel, a model using 20% gelatin and 10% gelatin is created for the tumor and the rest of the liver, respectively. It is found that the silicone modulus of elasticity matches with the real liver modulus of elasticity. It is also found that the 10% gelatin part of the ballistic gel model is an excellent emulation of a healthy human liver. Conclusion: The 3D flexible liver phantom made from a 10% gelatin-to-water mixture demonstrates decent fidelity to real liver tissue in terms of texture and elasticity. It holds significant potential for improving medical training, preoperative planning, and surgical research. We believe that continued development and validation of such models could further enhance their utility and impact in the field of hepatobiliary treatment planning and education. [ABSTRACT FROM AUTHOR]

Additional‐type liquid silicone rubber (ALSR) has poor mechanical properties, and conventional methods to reinforce it are at the cost of decreasing transparency. Here, vinyl MQ and fluorine‐containing MTQ silicone resins were synthesized by the sol–gel method. Then, high strength and ultraviolet (UV) transmitting ALSR were prepared using MQ and MTQ silicone resins as reinforcing agents, vinyl‐terminated silicone oil, and polydimethylmethylhydrosiloxane as matrix, respectively. The results show that the enhancement effect of MTQ silicone resin on the mechanical properties of ALSR resin is better than that of MQ silicone resin due to the vinyl content of MTQ silicone resin being higher than that of MQ silicone resin. Compared with pure ALSR, the tensile strength, Young's modulus, and Shore hardness of ALSR with 7 wt% MTQ silicone resin are enhanced by 435%, 127%, and 14%, respectively. The thermal stability of ALSR is slightly increased. The modified silicone rubber also has favorable transparency. Additionally, the MTQ/ALSR composites show higher UV transmittance than MQ/ALSR systems owing to the introduction of fluorine element increasing UV transmittance. The high strength and UV transmittance silicone rubber composites were prepared by using a small addition of MTQ silicone resin. [ABSTRACT FROM AUTHOR]

Congestive heart failure (CHF) is a fatal disease with progressive severity and no cure; the heart's inability to adequately pump blood leads to fluid accumulation and frequent hospital readmissions after initial treatments. Therefore, it is imperative to continuously monitor CHF patients during its early stages to slow its progression and enable timely medical interventions for optimal treatment. An increase in interstitial fluid pressure (IFP) is indicative of acute CHF exacerbation, making IFP a viable biomarker for predicting upcoming CHF if continuously monitored. In this paper, we present an inductor-capacitor (LC) sensor for subcutaneous wireless and continuous IFP monitoring. The sensor is composed of inexpensive planar copper coils defined by a simple craft cutter, which serves as both the inductor and capacitor. Because of its sensing mechanism, the sensor does not require batteries and can wirelessly transmit pressure information. The sensor has a low-profile form factor for subcutaneous implantation and can communicate with a readout device through 4 layers of skin (12.7 mm thick in total). With a soft silicone rubber as the dielectric material between the copper coils, the sensor demonstrates an average sensitivity as high as –8.03 MHz/mmHg during in vitro simulations. [ABSTRACT FROM AUTHOR]

Energy harvesting systems fabricated from rubber composite materials are promising due to their ability to produce green energy with no environmental pollution. Thus, the present work investigated energy harvesting through piezoelectricity using rubber composites. These composites were fabricated by mixing titanium carbide (TiC) and molybdenum disulfide (MoS2) as reinforcing and electrically conductive fillers into a silicone rubber matrix. Excellent mechanical and electromechanical properties were produced by these composites. For example, the compressive modulus was 1.55 ± 0.08 MPa (control) and increased to 1.95 ± 0.07 MPa (6 phr or per hundred parts of rubber of TiC) and 2.02 ± 0.09 MPa (6 phr of MoS2). Similarly, the stretchability was 133 ± 7% (control) and increased to 153 ± 9% (6 phr of TiC) and 165 ± 12% (6 phr of MoS2). The reinforcing efficiency (R.E.) and reinforcing factor (R.F.) were also determined theoretically. These results agree well with those of the mechanical property tests and thus validate the experimental work. Finally, the electromechanical tests showed that at 30% strain, the output voltage was 3.5 mV (6 phr of TiC) and 6.7 mV (6 phr of MoS2). Overall, the results show that TiC and MoS2 added to silicone rubber lead to robust and versatile composite materials. These composite materials can be useful in achieving higher energy generation, high stretchability, and optimum stiffness and are in line with existing theoretical models. [ABSTRACT FROM AUTHOR]

The development of polymer composites, considering the environmental issues, is aimed for minimizing the industrial content. New environmental-friendly nanocomposites, based on silicone rubber matrix and different concentrations of natural fiber/chromium oxide fillers, are prepared for the first time. The microstructural analysis confirms the successful obtaining of microfibers after treatment and chromium oxide nanoparticles and the formation of the final composite. The nanocomposites achieved improved physical and mechanical properties due to the dual effect of both fillers and attachment to the matrix. The 1% optimized nanocomposite achieved the highest modulus, dielectric properties, hydrophobicity, and surface stability. The effect of exposure to weathering conditions was studied. The characterization sentence asserts the preparation of a novel silicone rubber nanocomposite with improved properties, along with the environmental impact, regarding the dual effect of natural fiber waste and chromium oxide nanoparticles. [ABSTRACT FROM AUTHOR]

In order to ensure the operation and longevity of electronic devices, the design of multifunctional composites integrating microwave absorption (MA) and thermal conduction has become the key to solving the problem. However, the superior MA properties and thermal conductivity are usually incompatible in the blend system. In this study, a modified carbon fiber/silicone rubber‐oriented structure is designed based on the multiscale design concept of heterostructures with multiple interfaces. The forward deposition‐reverse growth mechanism is utilized at the microscopic level to construct multi‐interfacial heterogeneous structures on the surface of 1D carbon fibers (CFs). The magneto‐electric coupling network of the multi‐interfacial heterostructure induces interfacial polarization and enhances MA properties and heat transfer. Subsequently, the structural design of the modified CFs is carried out on a macroscopic scale using the ice template method. The directionally aligned modified CFs/silicone rubber aerogel composites are obtained by backfilling with silicone rubber (SR). The samples achieved an effective absorption bandwidth of 4.41 GHz and a maximum reflection loss of −42.29 dB with ultra‐thin thickness (1.3 mm). The thermal conductivity of the sample is improved to 200% compared to pure silicone rubber. The composites with directional alignment have promising applications in lightweight and flexible electronic packaging. [ABSTRACT FROM AUTHOR]

Relationship between the temperature of the electric field treatment (EFT) and the improvement of the effective thermal conductivity (TC) in the out‐of‐plane direction of the carbon nanofiber (CNF)/cured silicone rubber composite sheet was investigated to elucidate the appropriate operation of the EFT. Two types of silicone rubber precursors, with viscosities of 1.3 and 58 Pa∙s, were used. The effective TC gradually increased as the temperature during EFT increased from 40 to 80 °C. However, beyond 80 °C, the effective TC started to decrease and reached the same value as that of the sheet without EFT at 100 °C. This trend was observed regardless of the rubber species or CNF content. The influence of the EFT temperature was also discussed regarding the temperature dependency of the viscoelastic properties: storage modulus, loss modulus, and complex viscosity of the uncured precursor solution. When the temperatures were set at 80 °C, no significant changes were observed in the three‐viscoelastic properties for 60 min. On the other hand, a significant increase in the viscoelastic properties was observed after 10 min at 100 °C because of the start of the curing reaction, which supported the relationship between the temperature of the EFT and effective TC. [ABSTRACT FROM AUTHOR]

The combination of silicone rubber (SR) and ethylene‐propylene‐diene monomer (EPDM) could have an aggregate of their properties. High temperature vulcanized (HTV) is one of the most widely used SR type. This study explores the impact of montmorillonite Cloisite® layered silicate nanoclay on the vulcanization characteristics, mechanical‐dynamical behavior, and thermal properties of the HTV/EPDM blend. For this purpose, varying ratios of the HTV/EPDM compounds were prepared in the range of 100/0, 50/50, and 0/100, with 0, 3, and 5 wt% of Cloisite® using an internal mixer. The X‐ray diffraction results indicate that the mixing time, Cloisite® content and base polymer significantly influence the distance between Cloisite® layers. Cloisite® was found to accelerate the curing system and reduce the difference between minimum and maximum torque. The mechanical analysis of the prepared HTV/EPDM/clay nanocomposites revealed an increase in hardness, tensile strength, and modulus for samples with applied Cloisite® content. The degradation temperature was raised in HTV base samples by the presence of Cloisite®. On the other hand, the degradation temperature was dropped in the EPDM base samples as the amount of Cloisite® increased. In the HTV/EPDM/clay compounds, the degradation temperature was between the degradation temperatures of pure HTV and EPDM rubbers. [ABSTRACT FROM AUTHOR]

The three‐dimensional (3D) boron nitride (BN) thermal conductive networks, crafted through layer‐by‐layer assembly, hold tremendous potential for the development of insulating thermal interface materials (TIMs) with exceptional thermal conductivity. Nevertheless, maintaining the thermal conductive stability of this structure type during application remains a considerable challenge. Herein, initially, the honeycomb networks of boron nitride/nanodiamond (ND/kBN) with interlocking interfaces were prepared by electrostatic self‐assembly and ice template method. Subsequently, thermal conductivity composites of flexible silicone rubber (VQM) were acquired through vacuum‐assisted infiltration. The composites demonstrated improved through‐plane thermal conductivity with 1.03 W/(m K) at a 9.9 vol% content of ND/kBN while exhibiting relatively ideal dielectric properties. More importantly, the thermal conductive properties of the composites still maintain at 96.1% and 91.9%, respectively, even after undergoing 30% compressive deformation for 1 h and being bent 300 times. This study presents a novel strategy that not only improves the thermal conductivity of composites but also ensures the reliability of their applications. Highlights: Nanodiamond (ND) is anchored onto the kBN surface by electrostatic self‐assembly.ND/kBN filler honeycomb network with an interlocking interface was prepared.Flexible composites with high thermal conductivity (TC) were prepared.The composites exhibit excellent TC stability after experiencing deformation. [ABSTRACT FROM AUTHOR]

A series of halloysite nanotube‐silica (HNTs‐SiO2) nanocomposite fillers were prepared by in‐situ assembly, and a reinforced SiO2/SR composite was obtained by filling them into silicone rubber (SR). The morphology and structural characterization of HNTs‐SiO2 and HNTs‐SiO2/SR and the properties of the HNTs‐SiO2/SR were studied. As a result, the small particle size SiO2 was firmly anchored onto the HNTs surface, and the obtained HNTs‐SiO2 nanofillers were uniformly dispersed in SR. At a 30 phr fixed filler loading, the weakest filler network and the best filler dispersion were obtained when HNTs content in HNTs‐SiO2 was 5%. This resulted in a maximum tensile strength obtained of 6.2 MPa, 1.55 times that of SiO2/SR with the same filler loading, and a maximum elongation at break of 418%, 1.67 times that of the SiO2/SR with the same filler loading, and at the same time the tearing strength and hardness are also improved. Furthermore, the silicone rubber also showed improved thermal stability, with an initial degradation temperature increase of 30°C under a nitrogen atmosphere. Highlights: HNTs–SiO2 nanocomposites were successfully prepared by the self‐assembly method and used as fillers in SR as a new type of reinforcing material.The 1D HNTs act as a barrier to prevent SiO2 aggregation and improved fillers dispersion.The elongation at break and tensile strength of 5% HNTs‐SiO2/SR are 67% and 55% higher than those of SiO2/SR, respectively.The silicone rubber also showed improved thermal stability. [ABSTRACT FROM AUTHOR]

Highlights Dielectric elastomers (DEs), have attracted interest because they can replicate the behavior of muscles. They can change shape when subjected to an electric field. A novel DE is proposed in this study that incorporates silicon carbide (SiC) nanowires into silicone rubber (SR). The nanowires were propagated using polycarbosilane via a chemical vapor reaction (CVR). A boronate polymer was employed to promote compatibility between SR and SiC nanowires which modified the nanowire surfaces, leveraging a strong adhesive quality of the catechol moiety. Electrohydrodynamic (EHD) inkjet printing was then used to form the DEs into various shapes. These DEs had substantial dielectric constants of the order of 4.46. Significantly, one of the DEs achieved the highest actuated area strain of 20.36% in an electric field of 16.5 V/μm, demonstrating excellent driving performance. Furthermore, when used the fabricated DEs showed pronounced long‐term stability, meaning they are capable of finding applications in artificial intelligence, biomimetics, aerospace, and other disciplines. The SiC nanowires were obtained through a chemical vapor reaction. A boronate polymer with catechol moiety was used to modify the SiC nanowires. DEs were formed various shapes by inkjet printing. DEs achieved very large actuated strains of up to 20.36% at 16.5 V/μm. [ABSTRACT FROM AUTHOR]

Highlights The over‐loading of heat‐resistant fillers in silicone rubber creates a contradiction between heat resistance and mechanical properties, thus greatly limiting the durability of silicone rubber products in cutting‐edge applications and complex scenarios. To address this issue, silicone rubber was filled with octavinyl polyhedral oligomeric silsesquioxane (POSS) and carbon nanotubes (CNT) and crosslinked with 2,5‐dimethyl‐2,5‐di(tert‐butylperoxy)hexane (DBPMH) in an attempt to obtain composites with excellent mechanical properties and great thermal stability. Optical microscopy and X‐ray diffraction analyses revealed the size of POSS crystals decreased and the characteristic peaks disappeared after the peroxide crosslinked the polymer at elevated temperature. Specifically, silicone rubber composite filled with 0.1 phr POSS and 1.0 phr CNT exhibited a tensile strength of 10.2 MPa and elongation at a break of 450%. Further, the strength and elongation could be kept after thermo‐oxidative aging at 250°C for 32 h. Thermogravimetric analysis results demonstrate that the addition of POSS and CNT into silicone rubber exhibits a synergistic effect, markedly improving the thermal stability of the material. This method provides a valuable reference for manufacturing silicone rubber products that possess both excellent mechanical properties and high thermal stability under extreme working conditions. A novel silicone rubber composite with excellent mechanical properties and thermal stability was prepared. A small amount of octavinyl polyhedral oligomeric silsesquioxane (POSS) and carbon nanotubes exhibited a synergistic effect to improve thermal stability. The dependence of the morphological evolution of POSS crystals in SR on the 2,5‐dimethyl‐2,5‐di(tert‐butylperoxy)hexane and temperature was studied. [ABSTRACT FROM AUTHOR]

To avoid risks of mucosal infection from contact lenses removal, a contact lens plunger is often used. Given various types of contact lens plungers available on the market, no study has yet been done on mechanical effects of the contact lens plunger on contact lens removal. Here, this study used finite element analysis to investigate the effects of plunger size and plunger position on the removal of soft and rigid gas permeable (RGP) contact lenses. First, we established finite element analysis models for the plunger, contact lens, cornea, and aqueous humor. The plunger is made of mostly silicone rubber, and the contact lenses are mainly made of soft and hard material. The part of the plunger used for removal was located either at the central or the edged position, with pulling 1 mm distance. The main parameters observation indicators of in this study were the reaction force at the fixed end of the cornea, aqueous humor, the von Mises stress of the plunger, the contact lenses, and the cornea. Results of this study showed that when a plunger of a larger diameter was used, the reaction force of the plunger was also larger, especially when applied to RGP lenses, which required a slightly larger force (∼0.27 N). Also, when removing a RGP lens from the edge, there was a greater stress at the edge of the contact lens (2.5799 MPa), and this caused a higher stress on both the cornea (0.0165 MPa) and the aqueous humor (0.00114 MPa). When using a plunger with a larger diameter to remove a RGP lens, although a larger force required, the relatively larger contact area likely reduced the stress on the cornea and aqueous humor, thereby reducing the risk of eye injury. In addition, when removing a RGP lens, the results of this study recommended it to be removed from the plunger edge, as that facilitated the removal of contact lens. [ABSTRACT FROM AUTHOR]

Co‐filled composites of micro magnesium dihydrate (MDH) and hydrophobically treated nano aluminum nitride (nH‐AlN) fillers in high temperature vulcanizing silicone gum are studied for thermal and dielectric characteristics for use as an insulating material in high voltage applications. The study begins with description of the compounding protocol adopted, followed by spectroscopic and optical characterization. Fourier transform infrared spectroscopy (FTIR) and energy dispersive X‐ray spectroscopy (EDX) analysis are used to verify the presence of nH‐AlN and MDH in the composites. Thermal analysis through thermogravimetric analysis revealed a stark enhancement in the onset of polymer degradation temperature, with an improvement of 208 °C achieved at 30 phr by weight loading level of MDH. Volume resistivity of 9.71 E14 Ω‐cm is obtained at 30 phr weight loading of MDH and 5 phr of nH‐AlN. AC, +DC, and −DC dielectric strength improved by 1.09, 2.06, and 1.08 times for co‐filled composites at 30 phr MDH and 5 phr nH‐AlN loading levels over unitary filled composite. Effect of dielectric polarization on dielectric constant and dissipation factor is studied at various frequencies. Limitations while conducting dry arc resistance test at standard voltage of 12.50 kV is discussed, with modification in dry arc resistance test voltage to 16.95 kV. The results are presented and discussed here. [ABSTRACT FROM AUTHOR]

The current study investigates the impact of interfacial interactions between the silicone rubber base polymer matrix and the hexagonal boron nitride (hBN) nanofiller, incorporated at different weight percentages, on electrical, thermal, and mechanical properties. The adhesion of filler to the polymer is examined through swelling tests and Kraus plots and the elastic modulus calculated has a good agreement with the experimental data. The addition of 3 wt% of BN nanofiller with silicone rubber led to a 25.4 % increment in surface discharge inception voltage (SDIV). The Thermogravimetric analysis (TGA) shows that the BN filler included samples have high degradation temperature and thermal activation energy. The introduction of filler into the base polymer matrix significantly enhances mechanical properties, specifically tensile strength, tensile modulus, and percentage elongation at break. [ABSTRACT FROM AUTHOR]