General information concerning different kinds of chemical additives used in the textile industry has been described in this paper. The properties and applications of organofunctional silanes and ...polysiloxanes (silicones) for chemical and physical modifications of textile materials have been reviewed, with a focus on silicone softeners, silane, and silicones-based superhydrophobic finishes and coatings on textiles composed of silicone elastomers and rubbers. The properties of textile materials modified with silanes and silicones and their practical and potential applications, mainly in the textile industry, have been discussed.
Low molecular weight, highly crosslinked silicone resins are widely used as reinforcing agents for highly transparent elastomers and adhesion/tack promoters in gels. The resins are complex mixtures ...and their structure / property relationships are ill defined. We report the synthesis of a library of 2, 3 and 4-fold hyperbranched polymeric oils that are comprised of linear, lightly branched or highly branched dendronic structures. Rheological examination of the fluids and tack measurements of gels filled with 10, 25 or 50% dendronic oils were made. Viscosity of the hyperbranched oils themselves was related to molecular weight, but more significantly to branch density. The properties are driven by chain entanglement. When cured into a silicone gel, less densely branched materials were more effective in improving tack than either linear oils or Me
SiO-rich, very highly branched oils of comparable molecular weight, because the latter oils underwent phase separation.
The hydrophilic surfaces of nanosilica particles were modified to achieve a hydrophobic characteristic using a vinylsilane coupling agent. The effects of the modified nanosilica content on the ...electrical and mechanical properties of a silicone rubber nanocomposite were studied for application toward heavy electrical equipment. The modification of the nanosilica particles was confirmed using Fourier-transform infrared spectroscopy (FT-IR) and thermogravimetric analysis (TGA). A silicone rubber nanocomposite was prepared by mixing liquid silicone rubber (LSR) with vinylsilane-modified nanosilica particles at a weight ratio of 100 to 0–30 g. To observe the even dispersion of nanosilica particles in the LSR matrix, transmission electron microscopy (TEM) was used and it was found that the surface-modified nanosilicas were well dispersed in a 52–78 nm cluster formation. The electrical (alternating current (AC) breakdown strength and dielectric properties) and mechanical (tensile strength and elongation) properties were measured, and the AC insulation breakdown strength and tensile strength increased with an increase in the amount of modified-nanosilica.
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•Liquid silicone rubber (LSR) was mixed with nanosilica particles for application toward heavy electrical equipment.•Hydrophilic surface of nanosilica was modified with hydrophobic vinylsilane coupling agent.•Tensile strength of LSR/nanosilica (30 wt%) is 6.15 MPa, which is 27.9-times higher than that of neat LSR.•Electrical breakdown voltage for LSR/nanosilica (30 wt%) is 22.21 kV/mm, which is 14.1% higher than that of neat LSR.
To propose the InTraocular EMulsion of Silicone oil (ITEMS) grading system for the assessment of silicone oil (SiO) emulsion, applicable in a routine clinical setting and validated through an ...expert-led consensus procedure.
Seven experts on intraocular liquid tamponades, led by a facilitator, performed a literature review on the detection of SiO emulsion. Based on the proposed ideas, a questionnaire was developed and submitted to the experts on the methods to detect SiO emulsion and the items to grade. After 2 rounds of individual ranking using a 9-point scale and related discussion, the final grading system was developed including items that reached consensus (score ≥7 from ≥75% of members).
The agreed ITEMS grading system includes the identification of SiO microbubbles and large SiO bubbles through slit-lamp biomicroscopy, gonioscopy, fundus examination under mydriasis, or ultra-wide-field fundus photography. Moreover, macular and disk optical coherence tomography are used to detect SiO-associated hyperreflective dots.
An evidence-based expert-led consensus was conducted to develop grading system of SiO emulsion, allowing, for the first time, homogenous collection of data on SiO emulsion. This has the potential to improve the understanding of the role and clinical relevance of SiO emulsion, allowing comparisons between different studies.
Flexible capacitive sensors based on silicone rubber have gained importance in both academic and industrial fields due to their advantages, including low power consumption and high stability to ...temperature, and humidity. However, pristine silicone rubber has a low dielectric constant (ε′), requiring the use of dielectric additives such as TiO2, BaTiO3, or Sb2O3‐doped SnO2 rutile‐modified particles (ATO) to enhance electrical properties, but they also increase Young's modulus (E). To overcome this problem, liquid silicone rubbers (LSR) are commonly used in academic research due to their low E, but they often compromise mechanical integrity. In contrast, high‐consistency silicone rubbers (HCR), the industry commodity, maintain mechanical integrity even at high filler loadings but are limited in their use in dielectrics due to high E values. This paper explores the potential of vinyl‐terminated HCR for developing dielectric composites with high electromechanical response, with an improved ε′ and a reduced E while retaining mechanical and processability properties. The resulting dielectric HCR formulations exhibit optimal properties for developing flexible capacitive sensors using well‐established industrial products and processes.
In this work, a dielectric high‐consistency silicone rubber (HCR) has been compounded. The use of Sb2O3‐doped SnO2 rutile‐modified particles (ATO) has significantly improved the dielectric constant, while Young's modulus has been reduced by using a vinyl‐terminated silicone gum. This high‐flexibility dielectric HCR aims to effectively contribute to the industrial transference for the design of flexible capacitive sensors.
Silicone elastomers are promising materials for dielectric elastomer transducers (DETs) due to their superior properties such as high efficiency, reliability and fast response times. DETs consist of ...thin elastomer films sandwiched between compliant electrodes, and they constitute an interesting class of transducer due to their inherent lightweight and potentially large strains. For the field to progress towards industrial implementation, a leap in material development is required, specifically targeting longer lifetime and higher energy densities to provide more efficient transduction at lower driving voltages. In this review, the current state of silicone elastomers for DETs is summarised and critically discussed, including commercial elastomers, composites, polymer blends, grafted elastomers and complex network structures. For future developments in the field it is essential that all aspects of the elastomer are taken into account, namely dielectric losses, lifetime and the very often ignored polymer network integrity and stability.
Silicone elastomers are favorable materials for dielectric elastomer transducers (DETs), but for the field to progress, a leap in material development is required and it is essential that all aspects of the elastomer are taken into account. Here, the current state of silicone elastomers for DETs is summarised and critically discussed.
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Silicone oil (SiO) has a well‐established role as a long‐term endotamponade agent in the management of complicated retinal detachments. Complications of intraocular SiO include keratopathy, ...glaucoma, cataract and subretinal migration of the oil droplets. SiO tamponade can also lead to a severe optic neuropathy caused by retrolaminar migration. Nevertheless, intracranial migration of the SiO through the optic nerve posterior to the lamina cribrosa to the optic chiasm and brain is uncommon. The mechanism is still under debate, but it has been suggested elevated intraocular pressure, macrophages or optic nerve head anatomical predispositions as potential explanations. Moreover, central scotoma may develop in eyes with SiO not only at the time of oil removal, but also during the period of tamponade. We performed a PubMed search of neuronal complications of silicone oil over a period of 25 years. This review summarizes our current understanding of the specific pathogenic mechanisms of intraocular SiO neuronal side effects, concluding that pre‐existing glaucoma and optic nerve abnormalities are the main risk factors associated with this damage. In their absence, the risk of extraocular SiO penetration is so low that the use of SiO endotamponade in complex retinal detachment patients does not need to be modified. MRI images to assess extraocular SiO migration are only necessary in very few and special cases, such as patients with optic nerve abnormalities and glaucoma.
High integration development of electronics requires materials possessing excellent thermal conductivity, electromagnetic interference (EMI) shielding, and electrical insulation. In this work, Fe2O3 ...particles are deposited on carbon fibers (CF) and then utilized as fillers (CF@Fe2O3) in boron nitride/silicone rubber (BN/SR) to fabricate sandwich structured CF@Fe2O3/(BN/SR) composites, herein, BN/SR as top & substrate layer, and CF@Fe2O3 as middle layer. Orientation of BN in CF@Fe2O3/(BN/SR) composites realizes excellent in-plane thermal conductivity coefficient (λ∥), and the core-sheath structure of CF@Fe2O3 achieves good EMI shielding performance by the “absorption-reflection (transmittance)-reabsorption” process of electromagnetic waves, insulation modification of CF and the sandwich structure strengthen the electrical insulation. When the amount of BN and CF@Fe2O3 are 20.6 wt% and 45.5 wt%, respectively, the λ∥, EMI shielding effectiveness, volume resistance and breakdown strength of CF@Fe2O3/(BN/SR) composites reach 3.86 W/(m·K), 37.7 dB, 6.2 × 1014 Ω cm and 26.8 kV/mm, respectively, which are all higher than those of commonly fabricated CF/(BN/SR) composites with same amount of BN and CF (3.83 W/(m·K), 19.4 dB, 8.6 × 1013 Ω cm and 21.4 kV/mm). CF@Fe2O3/(BN/SR) composites possess better cooling effect (5.6 °C) than that of commercial silicon grease (QM850) on the testing platform of computer's central processing unit, whose functions are more abundant and have wide application prospects in electronics.
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•Designing core-sheath CF@Fe2O3 to enhance electromagnetic interference (EMI) shielding and reduce electrical conductivity of carbon fiber (CF).•Realizing orientation of boron nitride to enhance the in-plane thermal conductivity.•Silicone rubber composites possess excellent thermal conductivity, EMI shielding and insulating performances.
Purpose
To evaluate the inflammation associated with the use of standard silicone oil (polydimethylsiloxane; PDMS) and heavy silicone oil (HSO) Densiron‐68™ in patients undergoing vitrectomy for ...retinal detachment.
Materials and Methods
A prospective study was performed involving 35 patients scheduled to undergo vitrectomy for retinal detachment. Patients received PDMS or Densiron‐68™ HSO according to superior or inferior retinal localization of the tears, respectively. For assessing the inflammation, prostaglandin E2 (PGE2) and interleukin‐1α (IL‐1α) levels were evaluated in the aqueous.
Results
Thirty‐five eyes of 35 patients completed the study: 20 eyes received HSO, and 15 eyes received PDMS. The mean aqueous PGE2 level was significantly higher in HSO patients than in PDMS patients (869.16 ± 242.83 pg/ml versus 369.38 ± 209.7 pg/ml, respectively; p < 0.0001). The mean aqueous IL‐1α level was also significantly higher in HSO patients than in PDMS patients (81.40 ± 36.9 pg/ml versus 40.8 ± 32.5 pg/ml, respectively; p = 0.002). In HSO, a moderate positive correlation between the endotamponade duration and both PGE2 (r = 0.44; p = 0.05) and IL‐1α (r = 0.48; p = 0.033) levels was observed. In PDMS, a strong positive correlation between the endotamponade duration and both PGE2 (r = 0.89; p < 0.0001) and IL‐1α (r = 0.68; p = 0.006) levels was observed.
Conclusion
Although both HSO and PDMS yielded favourable success rates in the surgical treatment of complicated retinal detachments, HSO triggered a more severe inflammatory reaction, in a time‐dependent manner.
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