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... The breadth of utility of a commercially available and stable strong Lewis acid catalyst, tris(pentafluorophenyl)borane, has been explored, highlighting its use towards a wide range of unique siloxane products and their corresponding applications. This article focuses on the variety of different outcomes that this impressive borane offers in controlled and selective manners by the variation of rea ...
... Flexible core–shell 3D structures are essential for the development of soft sensors and actuators. Despite recent advancements in 3D printing, the fabrication of flexible 3D objects with internal architectures (such as channels and void spaces) remains challenging with liquid precursors due to the difficulty to maintain the printed structures. The difficulty of such fabrication is prominent especi ...
... Inorganic particles with photocatalytic properties are excellent candidates for the fabrication of micromotors. To achieve self-propulsion, the geometric and chemical symmetries of inorganic particles should be broken. However, the synthesis of micromotors with different geometric and chemical symmetries remains challenging. In this paper, a simple synthesis method is proposed to prepare rod-shape ...
siloxanes, etc ; molecular weight; organocatalysts; polymerization; Show all 4 Subjects
Abstract:
... Precise synthesis of well-defined functional polysiloxanes on demand was challenging due to chain transfer and backbiting side reactions during ring-opening polymerization (ROP) of cyclosiloxane monomers. In this contribution, a trisphosphazene base (C₃N₃-Me-P₃) with medium basicity and bulky molecular size was demonstrated as an effective organocatalyst to realize the controlled ROP of hexamethyl ...
siloxanes, etc ; durability; friction; lubrication; silica; Show all 5 Subjects
Abstract:
... With the development of microelectromechanical systems (MEMS), ultrathin dry lubrication coatings have received significant attention. In this study, a nanoscale organic–inorganic hybrid lubricative coating (OHL) with a low friction coefficient and wear resistance was developed by grafting polysiloxane brushes on an inorganic silica sol layer. Friction evaluations, including the friction coefficie ...
siloxanes, etc ; cellulose; color; cotton; emulsions; latex; Show all 6 Subjects
Abstract:
... In this paper, acrylate-terminated polysiloxane was synthesized and used as raw materials for the synthesis of cationic core/shell polysiloxane acrylate emulsion, which was applied as binders in the pigment dyeing of cotton fabrics. The experimental results showed that: the cationic core/shell polysiloxane acrylate emulsion in this article is in nano size of 100 nm. During the film formation of th ...
siloxanes, etc ; Suzuki reaction; organic chemistry; oxygen; regioselectivity; Show all 5 Subjects
Abstract:
... An efficient palladium-catalyzed Suzuki–Miyaura cross-coupling reaction of oxygen atom-substituted allylboronates with aryl/vinyl bromides, iodides, and triflates has been developed. The present coupling reactions proceeded smoothly to provide a variety of allylic siloxanes with high efficiency and excellent regioselectivity. This protocol features broad substrate scope, excellent functional group ...
siloxanes, etc ; crosslinking; emulsions; hydrogenation; microstructure; nanocatalysts; palladium; styrene; Show all 8 Subjects
Abstract:
... Cross-linking of poly(hydromethylsiloxane) (PHMS) with 1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasiloxane (D₄ⱽⁱ) in water-in-oil high internal phase emulsion (HIPE) whose aqueous phase comprises PdCl₂ is developed as a new, one-step route for the fabrication of polysiloxane-based, porous HIPE-templated materials (polyHIPEs) containing palladium. It is shown that the microstructure of the sys ...
siloxanes, etc ; air; ambient temperature; crosslinking; electronics; strength (mechanics); Show all 6 Subjects
Abstract:
... While polysiloxanes are the most widely used interface materials for on-skin electronics, they usually do not exhibit mechanical robustness and fast healing speed simultaneously due to the inherent contradiction of this pair of performances, let alone combining self-adhesiveness, reconfigurability, etc. Herein, we address this conundrum by building polydimethylsiloxane–dithiothreitol block polymer ...
siloxanes, etc ; adhesion; carbon nanotubes; crosslinking; hydrogen; imines; tensile strength; Show all 7 Subjects
Abstract:
... The facile fabrication of robust, self-healable, and re-dissolvable polysiloxane elastomers for use in recyclable flexible devices is highly desired yet quite a challenge. Herein, a strategy involving dual-crosslinking side chains with an asymmetric chain structure is proposed to overcome the related challenges. Dual crosslinking is readily undergone between diethylenetriamine-functionalized polys ...
siloxanes, etc ; durability; energy; liquids; polyesters; soybean oil; water vapor; Show all 7 Subjects
Abstract:
... Superamphiphobic surfaces progress rapidly but suffer from the issues of low repellency to hot liquids, complicated and nonaqueous preparation methods, and low durability. Here, a simple waterborne approach is developed to fabricate robust superamphiphobic fabrics with excellent hot liquid repellency and hot water vapor resistance. First, a perfluorodecyl polysiloxane (FD-POS) aqueous suspension w ...
siloxanes, etc ; biogas; energy; experimental design; sewage; sorbents; wastewater treatment; Show all 7 Subjects
Abstract:
... The use of biogas, one of the main players in the energy transition, requires the efficient removal of harmful traces of impurities. Reliable and robust purification systems are therefore required before the biogas is fed into cogeneration or upgrading plants. In this work, an industrial-scale biogas purification system for the deep removal of impurities is analysed. The experimental design phase ...
siloxanes, etc ; absorbents; absorption; contact angle; cotton; hydrolysis; hydrophobicity; wettability; Show all 8 Subjects
Abstract:
... The creation of a superhydrophobic surface with simplified hydrophobic steps still faces great challenges. Herein, an in situ one-step hydrophobic strategy of growing polysiloxane nanofilaments onto pristine rod-shaped cotton stalk (CS) surface is used to prepare a new bulk superhydrophobic CS absorbent. The rich hydroxyl groups contained in CS directly polymerize with the silanols generated by th ...
siloxanes, etc ; air; energy; filtration; hexadecane; liquids; oils; polytetrafluoroethylene; silica; smoke; Show all 10 Subjects
Abstract:
... Polytetrafluoroethylene (PTFE) membranes with three-dimensional interconnected porous networks are usually used as air filters. However, they are easily contaminated by oily aerosols in air filtration, resulting in a decrease in filtration efficiency. Herein, a strategy for the preparation of amphiphobic PTFE membranes with a ring-on-string-like micro/nano structure for air purification was propos ...
siloxanes, etc ; Gibbs free energy; hydrolysis; micelles; silica; surface tension; topology; Show all 7 Subjects
Abstract:
... The thermodynamic picture describing the formation mechanism of bicontinuous concentric lamellar (bcl) nanostructured silica particles, bcl silica, was investigated thoroughly. A series of classical kinetics of bcl silica by varying the synthesis time were employed to observe the morphological evolution of bcl silica. The formation mechanism of bcl silica is proposed as the hydrolysis and condensa ...
siloxanes, etc ; desorption; energy; hydrophilicity; hydrophobicity; perlite; sorption; surface roughness; vapors; wettability; Show all 10 Subjects
Abstract:
... Although expanded perlite with abundant sources and low cost has been widely used in a diverse of different fields, it still requires multi-step processing to prepare desired functional materials, leading to complicated experimental procedures. And imparting new functionalities to expanded perlite with simple and effective methods remains a challenge. In this paper, a novel facile chemical vapor d ...
siloxanes, etc ; Japan; aquatic environment; estuaries; industrialization; pollution; sewage treatment; surface water; Show all 8 Subjects
Abstract:
... We investigated mass loading and the spatial distribution of volatile methylsiloxanes (VMSs) including four cyclic VMSs (D3–D6; cVMSs, the number refers to the number of SiO bonds) and three linear VMSs (L3–L5; lVMSs) in Tokyo Bay, Japan, which is one of the most industrialized, urbanized, and populated areas in the world. Based on the VMS concentrations determined in eight main inflow rivers to t ...
siloxanes, etc ; friction; hardness; hydrophilicity; process design; quaternary ammonium compounds; water vapor; wettability; Show all 8 Subjects
Abstract:
... The wettability, breathability, and softness of fabrics are difficult to effect synergistically, so they cannot meet the requirements of personal comfort. Here, inspired by some amazing superhydrophilic structures in nature, a synergistic strategy is reported to create a novel Bola quaternary ammonium polyether polysiloxane (BQPEPS) with a water transport channel and softness performance with a un ...
siloxanes, etc ; Aspergillus; Penicillium; biodegradation; crosslinking; dust; glass; humidity; pollution; polymethylmethacrylate; silicon; temperature; Show all 12 Subjects
Abstract:
... Objects and structures made of organic glass require protection from damage caused by external factors. Light, humidity, temperature, dust pollution and, undoubtedly, microorganisms lead to the deterioration of optical and mechanical properties. Polysiloxane-based protective coatings, consisting of silicon–oxygen backbones linked together with organic side groups attached to the silicon atoms, are ...
siloxanes, etc ; biodegradability; cellulose; crosslinking; foams; hydrophobicity; pollution; starch; tensile strength; water uptake; Show all 10 Subjects
Abstract:
... The disposal of non-degradable plastic packaging and plastic pollution are widespread environmental problems. The development of a fully biodegradable alternative foam packaging with excellent water barrier properties from polysaccharides is quite challenging. In this work, micro-fibrillated cellulose fiber-reinforced starch foams (MFC-SFs) were developed by crosslinking with two poly(siloxane)-ba ...