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Hydrogel-based soft materials have attracted significant attention in various fields due to their high water content, good biocompatibility, and variable mechanical strength. However, due to the hydrophilic properties of hydrogel networks, most of the hydrogel-based soft materials are easy to swell in water and have monotonous surface wettability. Here, taking advantage of the intrinsic hydrophobicity of siloxane, novel heteronetwork organohydrogels were synthesized by covalently integrating reactive siloxane monomers into the hydrophilic hydrogel networks via emulsion polymerization. The surface of the heteronetwork organohydrogels exhibited adaptive wettability owing to the rearrangement of the surface chemistry induced by varying solvent conditions. Moreover, the heterogeneous networks endowed organohydrogels with excellent anti-swelling abilities in water or oil (n-heptanes). The potential application of the prepared organohydrogels in the field of oil/water separation was also preliminarily explored. The idea and method of integrating polysiloxane into hydrogels in this study might provide a new insight to develop high-performance polysiloxane-based heteronetwork gel materials. [ABSTRACT FROM AUTHOR]

Smart windows can benefit from the use of photochromic wooden materials. In the current study, we report the preparation of fluorescent wood that can switch color under visible and ultraviolet lighting conditions. In order to develop a transparent wood that is both fluorescent and photochromic, a mixture of europium and dysprosium activated strontium aluminum oxide (EDSA) nanoparticles (NPs; 8–13 nm) and room-temperature vulcanizing (RTV) silicone rubber (Polysiloxane) was integrated into a delignified wood. EDSA is known for its excellent photostability and thermal stability. The EDSA phosphor has to be efficiently dispersed in RTV to avoid the formation of aggregates, allowing for a better fabrication of colorless wood. The coloration findings from the CIE Lab parameters displayed that when illuminated with ultraviolet rays, this colorless wooden substrate turned green. Using a transmission electron microscope (TEM), the morphological properties of the synthesized EDSA NPs were examined. Various analysis techniques, including elemental mapping, energy-dispersive X-ray (EDX), X-ray fluorescence spectroscopic analyzer (WDXRF), scanning electron microscope (SEM), hardness testing, and photoluminescence spectra, were employed to study the photochromic woods. An absorption band (365 nm) and two emission bands (436 nm and 518 nm) were determined for the prepared photoluminescent woods. When increasing the EDSA content, the results showed that the produced EDSA-infiltrated wood was more water-resistant and highly protective against UV radiation. Reversible photochromic responsiveness to UV light was observed for the prepared transparent luminous wood without fatigue. [ABSTRACT FROM AUTHOR]

This study broadens the application of 4‐acylpyrazolone, a leading β‐diketone chelating ligand, to include the removal of heavy metal ions in our current work. As organic–inorganic hybrids have gained considerable attention these days due to their widespread applications in the field of Chemistry, we have employed a Schiff base reaction to generate 4‐acetyl‐5‐methyl‐2‐phenyl‐2,4‐dihydro‐pyrazole‐3‐one incorporated polysiloxane material using a cost‐effective one‐pot synthesis. Optimization studies were performed to eliminate Pb(II), Cu(II), and Cr(VI) by varying the beginning metal ion content, the required amount of the adsorbent, pH, required time, and temperature. The considerable opportunity for monolayered chemisorption is illustrated by the observation that adsorption opts for the Langmuir adsorption isotherm, with R2 values of 0.99. It employs an endothermic adsorption mechanism in a study at multiple temperatures and follows a pseudo‐second‐order kinetic model. FMO and MESP investigations of complexes formed through adsorption were successfully carried out through DFT. Material reveals quick recycling up to three alternating rounds with removal efficiencies of 82%, 56%, and 47% for Pb(II), Cu(II), and Cr(VI), respectively. Therefore, it may further be used for extraction of heavy metals from industrial effluents and provides the basis for future scope of this type of organic–inorganic hybrids in water treatment. [ABSTRACT FROM AUTHOR]

Natural leather-based materials possess a combination of air permeability, wear resistance, and plasticity. However, conventional leather products have inherent limitations that make them unsuitable for unconventional applications. Therefore, it is necessary to develop new capabilities in order to overcome these limitations. In this study, we explored the conversion of regular leather into a high-strength product with hydrophobic properties through surface engineering. To achieve this, we synthesized polysiloxane-modified fluorinated waterborne polyurethane emulsions as functional coatings using emulsion polymerization. The structure and properties of the treated leathers were characterized using techniques such as Fourier transform infrared, thermogravimetry, X-ray photoelectron spectroscopy, X-ray diffraction, and scanning electron microscopy. The results demonstrated that the synthesized polysiloxane-modified fluorinated waterborne polyurethane successfully penetrated and combined with the fibers of the leather, resulting in excellent hydrophobicity. The water contact angle increased to 124.3°. Furthermore, the tensile strength and tear strength of unfinished leather are 875 N and 114 N, respectively. The application of waterborne polyurethane-derived functional additives as coatings resulted in a significant increase in tensile and tear strength of the leather by 60 N and 16 N, respectively. In addition, the softness of the leather increased from 7.6 mm to 10.09 mm. Overall, the use of this functional waterborne polyurethane coating will contribute to the diversification of leather applications. [ABSTRACT FROM AUTHOR]

The mechanochromic materials can respond to environmental changes by altering the optical properties of the system, which has garnered significant attention in recently. The utilization of these materials for the purpose of sensing tensile and compressive stress has been extensively documented. However, the mechanochromic polymer that can effectively discriminate hardness of inorganic particles is still rarely reported. In this article, a force‐sensitive organic polysiloxane was developed by introducing triethenyl‐substituted rhodamine derivatives crosslinker into the polymethylhydrosiloxane network through hydrosilylation addition reaction. The results demonstrated that the grinding of the crosslinked polysiloxane effectively facilitated the transmission of external force to the polymeric network, leading to an open ring isomerization of rhodamine accompanied by significant alterations in visible and fluorescent color. In addition, we found that the optical properties of the system showed distinct variations when the inorganic particles with different Moh's hardness were co‐ground with the polysiloxane. High Moh's hardness particles, such as Al2O3, could effectively trigger the mechanochromic behavior of the polymer, while Na2SO4 particles with low hardness failed to induce the corresponding change. Therefore, this organic polysiloxane could be used as a potential fluorescent indicator for hardness recognition. [ABSTRACT FROM AUTHOR]

Polymer‐derived ceramics (PDCs) remain at the forefront of research for a variety of applications including ultra‐high‐temperature ceramics, energy storage and functional coatings. Despite their wide use, questions remain about the complex structural transition from polymer to ceramic and how local structure influences the final microstructure and resulting properties. This is further complicated when nanofillers are introduced to tailor structural and functional properties, as nanoparticle surfaces can interact with the matrix and influence the resulting structure. The inclusion of crystalline nanofiller produces a mixed crystalline–amorphous composite, which poses characterization challenges. With this study, we aim to address these challenges with a local‐scale structural study that probes changes in a polysiloxane matrix with incorporated copper nanofiller. Composites were processed at three unique temperatures to capture mixing, pyrolysis and initial crystallization stages for the pre‐ceramic polymer. We observed the evolution of the nanofiller with electron microscopy and applied synchrotron X‐ray diffraction with differential pair distribution function (d‐PDF) analysis to monitor changes in the matrix's local structure and interactions with the nanofiller. The application of the d‐PDF to PDC materials is novel and informs future studies to understand interfacial interactions between nanofiller and matrix throughout PDC processing. [ABSTRACT FROM AUTHOR]

Purpose: The silicone modifications of two-component epoxy resin coatings are commonly built on epoxy resins rather than on epoxy curing agents. The silicone-modified epoxy curing agent system is rarely reported yet. This study aims to prepare the polysiloxane (PS)-modified waterborne epoxy coatings based on aqueous curing agents technology. Design/methodology/approach: Waterborne epoxy curing agents with different contents of terminal epoxy PS were synthesized by reacting with triethylenetetramine, followed by incorporating of epoxy resin (NPEL-128) and polyethylene glycol diglycidyl ether. The waterborne epoxy coatings were prepared with the above curing agents, and their performance was investigated through thermogravimetric analysis, scanning electron microscopy, mechanical characterization, gloss measurement, chemical resistance test and ultraviolet (UV) aging experiment. Findings: The results showed that the epoxy coating prepared by silicon-modified curing agent has higher gloss, better chemical resistance and UV resistance than the coating from unmodified curing agent with terminal epoxy PS and commercially available waterborne epoxy curing agent (Aradur 3986), as well as the competitive mechanical properties and heat resistance. Reduced water absorption on fibrous paper was also obtained with the help of silicon-modified curing agent. Originality/value: These findings will be valuable for resin researchers in addressing the modification issues about waterborne epoxy resin and curing agent. [ABSTRACT FROM AUTHOR]

Owing to their high significance in fundamental study and diverse applications, stimuli-responsive and fluorescent polymers, particularly those with cluster-triggered emission (CTE) featured by non-conjugated chromophores, have drawn tremendous attention in recent years. In this work, fluorescent and multi-responsive polysiloxane (FRPS) was synthesized by hydrolytic condensation polymerization of 3-aminopropyl methyl diethoxysilane (APMS) with 3-(N-isopropyl propionamide) iminopropyl methyl diethoxysilane (APMS-NIP), which was formed in situ through aza-Michael addition between APMS and N-isopropyl acrylamide. FRPS was not only highly sensitive to temperature, pH and CO2 in water, but also showed an enhanced and stimuli-adjustable fluorescence emission. The effects of monomer feeding, pH and CO2 on its lower critical solution temperature and fluorescent property were investigated. FRPS fluorescence emission was ascribed to CTE mechanism. In addition, FRPS was shown to be highly potential as physiological indicator for cell imaging, and for controlled release and trace detection of doxorubicin. This study provides therefore a type of stimuli-responsive and fluorescent material for potential applications in biomedical fields, and it is also of great significance for understanding of the fluorescence mechanism of polysiloxane-based stimuli-responsive polymers. [ABSTRACT FROM AUTHOR]

Transparent polysiloxane elastomers with good self-healing and reprocessing abilities have attracted significant attention in the field of artificial skin and flexible displays. Herein, we propose a simple one-pot method to fabricate a room temperature self-healable polysiloxane elastomer (HPDMS) by introducing dynamic and reversible imine bonds and boroxine into polydimethylsiloxane (PDMS) networks. The presence of imine bonds and boroxine is proved by FT−IR and NMR spectra. The obtained HPDMS elastomer is highly transparent with a transmittance of up to 80%. The TGA results demonstrated that the HPDMS elastomer has good heat resistance and can be used in a wide temperature range. A lower glass transition temperature (Tg, −127.4 °C) was obtained and revealed that the elastomer is highly flexible at room temperature. Because of the reformation of dynamic reversible imine bonds and boroxine, the HPDMS elastomers exhibited excellent autonomous self-healing properties. After healing for 3 h, the self-healing efficiency of HPDMS reached 96.3% at room temperature. Moreover, the elastomers can be repeatedly reprocessed multiple times under milder conditions. This work provides a simple but effective method to prepare transparent self-healable and reprocessable polysiloxane elastomers. [ABSTRACT FROM AUTHOR]

[Display omitted] Despite the advantages of easy moulding and excellent mechanical properties, there are still some shortcomings with polypropylene (PP) such as high flammability and poor ultra-violet (UV) resistance. In this work, modified zinc oxide (mZnO) was prepared by reacting zinc oxide nanoparticles (ZnO) with polysiloxanes, and the effect of mZnO on the effectiveness of intumescent flame-retardant and on the UV aging resistance of polypropylene were investigated. By introducing 16 wt% (intumescent flame-retardant /mZnO) and 0.3 wt% maleic anhydride-grafted PP (MAH-g-PP), the limiting oxygen index increased to 32.7 %, and passed UL-94V-0 rating. In comparison to the controls, the peak heat release rate and the peak smoke release rate were 88.5 % and 80 % lower, respectively. In addition, PP samples showed improved mechanical properties, with a 5 % increase in tensile properties compared to the pure PP sample. After 100 h of UV irradiation, the surface of the samples was relatively flat and smooth, and the carbonyl index decreased from 81.1 of neat PP to 26.7. PP composites with 100 h aging treatment still had excellent flame retardancy and mechanical properties. The results showed that mZnO was effective in improving the flame retardancy, mechanical properties and light aging tolerance of PP. This study provides a novel approach to fabricate long-life flame-retardant PP composites with low additive content. [ABSTRACT FROM AUTHOR]

Current research on materials engineering focuses mainly on bio-based materials. One of the most frequently studied materials in this group is polylactide (PLA), which is a polymer derived from starch. PLA does not have a negative impact on the natural environment and additionally, it possesses properties comparable to those of industrial polymers. The aim of the work was to investigate the potential of organosilicon compounds as modifiers of the mechanical and rheological properties of PLA, as well as to develop a new method for conducting mechanical property tests through innovative high-throughput technologies. Precise dosing methods were utilized to create PLA/silicone polymer blends with varying mass contents, allowing for continuous characterization of the produced blends. To automate bending tests and achieve comprehensive characterization of the blends, a self-created workstation setup has been used. The tensile properties of selected blend compositions were tested, and their ability to withstand dynamic loads was studied. The blends were characterized through various methods, including rheological (MFI), X-ray (XRD), spectroscopic (FTIR), and thermal properties analysis (TG, DSC, HDT), and they were evaluated using microscopic methods (MO, SEM) to examine their structures. [ABSTRACT FROM AUTHOR]

Nonconventional luminescent materials have been rising stars in organic luminophores due to their intrinsic characteristics, including water‐solubility, biocompatibility, and environmental friendliness and have shown potential applications in diverse fields. As an indispensable branch of nonconventional luminescent materials, polysiloxanes, which consist of electron‐rich auxochromic groups, have exhibited outstanding photophysical properties due to the unique silicon atoms. The flexible Si‐O bonds benefit the aggregation, and the empty 3d orbitals of Si atoms can generate coordination bonds including N → Si and O → Si, altering the electron delocalization of the material and improving the luminescent purity. Herein, we review the recent progress in luminescent polysiloxanes with different topologies and discuss the challenges and perspectives. With an emphasis on the driving force for the aggregation and the mechanism of tuned emissions, the role of Si atoms played in the nonconventional luminophores is highlighted. This review may provide new insights into the design of nonconventional luminescent materials and expand their further applications in sensing, biomedicine, lighting devices, etc. [ABSTRACT FROM AUTHOR]

In recent years, as an emerging dynamic bonding, silyl ether linkages have been concerned and applied. However, the reprocessability of vitrimers based on it is far from satisfactory because of the inactive dynamic exchange reaction. At the same time, the mechanical properties of polysiloxane elastomers are poor because of the high flexibility of polysiloxane molecular chains and weak intermolecular forces. Herein, we have successfully synthesized a PDMS elastomer incorporating Zn(II)‐amine coordination bonds as sacrificial units, which are crosslinked through dynamic silyl ether linkages. Importantly, the presence of Zn ions promotes the exchange between the silyl ether linkages and hydroxyl groups. The elastomers exhibited excellent mechanical properties (35 times improvement in toughness) and outstanding reprocessability. The mechanical property recovery of the PDMS elastomers reached approximately 90% after four reprocessing cycles. Meanwhile, small‐molecule simulation experiments were conducted to verify the significant catalytic effect of Zn (II) ions as Lewis acid catalysts on the exchange reaction of silyl ether linkages and hydroxyl groups. In a word, this work provides a facile strategy to simultaneously enhance the mechanical properties and reprocessing performance of silyl ether‐linked polysiloxane elastomers. [ABSTRACT FROM AUTHOR]

Developing a novel methodology for the synthesis of functionalized polysiloxanes is highly desirable because of their extensive applications in engineering, textile, construction, electronics, and medical systems. Herein we introduce the oxa-Michael addition reaction as an efficient methodology to prepare a series of functionalized polysiloxanes from hydroxyalkyl-containing polysiloxanes and vinyl monomers using phosphazene base as the catalyst. The effects of various factors, including reaction time, feed ratio and solvent, were explored in this reaction. It was found that the reaction can be carried out under mild reaction (room temperature in 6 h to 24 h) with moderate to high conversion yields (60% to 99%). In particular, vinyl monomers with strong electron-withdrawing groups (e.g., cyano and sulfone groups) have higher reactivity, and the functionalized polysiloxanes can be obtained quantitatively or near-quantitatively. Interestingly, their molecular weights determined by gel permeation chromatography (GPC) reveal that the Si-O-Si skeletons were attacked by phosphazene base and re-arranged during the reaction, thus leading to improved molecular weights and more uniform molecular weight distributions in the final products than the original polysiloxanes. Moreover, these polysiloxanes exhibited intriguing nonconventional fluorescence due to the presence of unique chromophores, and those containing cyano and sulfone groups particularly exhibit the best fluorescence performance. More organosilicon materials could be developed under this simple strategy.

In this study, organosilicon compounds were used as modifiers of filaments constituting building materials for 3D printing technology. Polymethylhydrosiloxane underwent a hydrosilylation reaction with styrene, octadecene, and vinyltrimethoxysilane to produce new di- or tri-functional derivatives with varying ratios of olefins. These compounds were then mixed with silica and incorporated into the ABS matrix using standard processing methods. The resulting systems exhibited changes in their physicochemical and mechanical characteristics. Several of the obtained composites (e.g., modified with VT:6STYR) had an increase in the contact angle of over 20° resulting in a hydrophobic surface. The addition of modifiers also prevented a decrease in rheological parameters regardless of the amount of filler added. In addition, comprehensive tests of the thermal decomposition of the obtained composites were performed and an attempt was made to precisely characterize the decomposition of ABS using FT-IR and optical microscopy, which allowed us to determine the impact of individual groups on the thermal stability of the system. [ABSTRACT FROM AUTHOR]

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Modifying bismaleimide (BMI) resin to improve its toughness and flame retardancy without sacrificing the glass transition temperature (Tg) and thermal decomposition stability is still a challenge. In this study, we employed the allyl ether of resveratrol (AER) and eugenol allyl ether grafted polysiloxane (PMES‐Allyl) to co‐modify BMI resin. For the BMI/AER/PMES‐Allyl (BAPA) resin, the content of PMES‐Allyl was 15 wt%, and the molar ratio of maleimide and allyl groups was controlled as 1:0.8. Compared to commercial 2,2′‐diallyl bisphenol A modified BMI (BD) resin, the BAPA resin exhibited superior thermal properties after curing, due to the role of AER in improving the crosslinking density and chain rigidity of the network. The cured BAPA resin had a Tg more than 380°C, and its initial thermal decomposition temperature (Td5%) and char yield (Y800°C) reached 424.8°C and 46.4%, respectively. Meanwhile, PMES‐Allyl as a rubber phase could effectively improve the toughness of the cured resin. The impact strength of the cured BAPA resin was 15.2 kJ/m2. Moreover, the two modifiers both helped to improve the flame retardancy of the material. Compared with the cured BD resin, the cured BAPA resin showed a decrease of peak heat release rate (PHRR), total heat release (THR), and maximum average rate of heat emission (MARHE) by 25.5%, 35.5%, and 31.5%, respectively. Its total smoke production (TSP) was only 35.6% of that of the cured BD resin. In addition, the cured BAPA resin also displayed a lowered water absorption and improved thermal aging resistance. Therefore, it is suggested to be a promising and high‐performance thermosetting resin for cutting‐edge applications. [ABSTRACT FROM AUTHOR]

Ethoxysilanes were hydrolyzed, and the resulting hydrolyzates were dimethylsilylated to produce Si–H terminated oligosiloxanes (CLs). These CLs were characterized using gel permeation chromatography, nuclear magnetic resonance, and Fourier-transform infrared spectroscopy. The results indicated the formation of highly condensed cyclic siloxanes, four-membered cyclic siloxanes, and linearly condensed cyclic siloxanes when derived from tetraethoxysilane, hexaethoxydisiloxane, and octaethoxytrisiloxane, respectively. The CLs were subsequently reacted with vinyl-terminated polydimethylsiloxane in the presence of the Karstedt catalyst to yield PDMS elastomers, which are comprised of di- and quadra-functional silicones. Tests for transmittance, thermal properties, tensile strength, and swelling in toluene were conducted to assess the impact of the molecular weight and microstructure of the CLs on the final products. As the number of silicon atoms in the ethoxysilanes increased, there was a rise in the secant modulus and a reduction in the degree of swelling. These findings suggest that the structure of PDMS elastomers can be tailored by varying the structure of the ethoxysilanes used as a cross-linking agent. Highlights: Si–H terminated oligosiloxanes were synthesized from hydrolyzates of tetraethoxysilane, hexaethoxydisiloxane, or octaethoxytrisiloxane and chloro(dimethyl)silane. PDMS elastomers were synthesized via the hydrosilylation of the Si–H terminated oligosiloxanes with vinyl-terminated polydimethylsiloxane. Secant modulus increased, while the degree of swelling decreased, with an increase in the number of silicon atoms in ethoxysilanes. Mechanical testing and the swelling test in toluene demonstrated that the structure of PDMS elastomers can be influenced by the structure of ethoxysilanes used as a cross-linking agent. [ABSTRACT FROM AUTHOR]

Curing process of siloxane polymer was studied by determining rate of heat released during Dynamic DSC analysis. Utilizing thermokinetics software were calculated model-free methods such as Kissinger, Flynn–Wall–Ozawa, Friedman and also model-fitting methods such as Coats Redfern. To improve accuracy, Khavam Flanagan's combined method was utilized and the third-order Avrami model was determined. Simulation of the curing process was done using OpenFOAM open-source software based on the finite volume method. Simulation results were validated using DSC Isothermal data. The results of the simulated sample were in good agreement with the experimental data. The curing time was investigated in cylindrical, spherical, and cubic shapes. The longest curing time was assigned to sphere geometry and the least to rectangular cubes with equal length and width. To achieve the optimal curing method, the influence of various parameters on the curing process of polysiloxane, including oven temperature, mold geometry, boundary conditions (effect of curing in a fan oven) and geometry dimensions, resin density, and thermal conductivity coefficient were investigated. [ABSTRACT FROM AUTHOR]

Developing a novel methodology for the synthesis of functionalized polysiloxanes is highly desirable because of their extensive applications in engineering, textile, construction, electronics, and medical systems. Herein we introduce the oxa-Michael addition reaction as an efficient methodology to prepare a series of functionalized polysiloxanes from hydroxyalkyl-containing polysiloxanes and vinyl monomers using phosphazene base as the catalyst. The effects of various factors, including reaction time, feed ratio and solvent, were explored in this reaction. It was found that the reaction can be carried out under mild reaction (room temperature in 6 h to 24 h) with moderate to high conversion yields (60% to 99%). In particular, vinyl monomers with strong electron-withdrawing groups (e.g., cyano and sulfone groups) have higher reactivity, and the functionalized polysiloxanes can be obtained quantitatively or near-quantitatively. Interestingly, their molecular weights determined by gel permeation chromatography (GPC) reveal that the Si-O-Si skeletons were attacked by phosphazene base and re-arranged during the reaction, thus leading to improved molecular weights and more uniform molecular weight distributions in the final products than the original polysiloxanes. Moreover, these polysiloxanes exhibited intriguing nonconventional fluorescence due to the presence of unique chromophores, and those containing cyano and sulfone groups particularly exhibit the best fluorescence performance. More organosilicon materials could be developed under this simple strategy. [ABSTRACT FROM AUTHOR]

Abstract Nonconventional luminescent materials have been rising stars in organic luminophores due to their intrinsic characteristics, including water‐solubility, biocompatibility, and environmental friendliness and have shown potential applications in diverse fields. As an indispensable branch of nonconventional luminescent materials, polysiloxanes, which consist of electron‐rich auxochromic groups, have exhibited outstanding photophysical properties due to the unique silicon atoms. The flexible Si‐O bonds benefit the aggregation, and the empty 3d orbitals of Si atoms can generate coordination bonds including N → Si and O → Si, altering the electron delocalization of the material and improving the luminescent purity. Herein, we review the recent progress in luminescent polysiloxanes with different topologies and discuss the challenges and perspectives. With an emphasis on the driving force for the aggregation and the mechanism of tuned emissions, the role of Si atoms played in the nonconventional luminophores is highlighted. This review may provide new insights into the design of nonconventional luminescent materials and expand their further applications in sensing, biomedicine, lighting devices, etc.

In order to improve the problems of traditional self‐healing polyurethane coating, such as harsh curing and repair conditions, poor hydrophobicity, thermal stability and human affinity, the prepolymer was synthesized by bio‐based polyol castor oil (CO), self‐made alkyl aryl modified silicone polyol (SiOH) and isophorone diisocyanate (IPDI), and dimethylglyoxime (DOU) was used as chain extender containing dynamic imine bond, methacrylic acid 2‐(tert‐butylamino)ethyl ester (MABE) was used as a capping agent containing acrylate and high steric hindrance amino structure, and a UV curable room temperature repair bio‐based poly(siloxane‐urethane) coating (PUESi) was prepared by stepwise polymerization. In this article, the effect of the amount of DOU on the properties of PUESi was studied. The results showed that PUESi with different dosages of DOU could achieve self‐healing at room temperature. The maximum repair efficiency of full cut could reach 91.8%, and the scratch repair efficiency could reach 99.3%; The contact angle meter and synchronous thermal analyzer proved that the introduction of SiOH significantly improved the hydrophobicity, oil repellency and thermal stability of PUESi. The water contact angle increased from 78° to 104°, the oil contact angle increased from 63° to 91°, and the 5% thermal decomposition temperature increased from 179 to 196°C. The coating has broad application prospects in the fields such as antifouling and anticorrosion, building material protection, and automotive instruments. [ABSTRACT FROM AUTHOR]

To study the effect of polymeric structures on second‐order nonlinear optical properties, polysiloxanes materials based on azobenzene as chromophore have been designed and synthesized successfully. Herein, the siloxane monomer is directly bonded to azobenzene units by palladium catalysis, which avoids the influence of flexible chains on the photoelectric properties of azobenzene. According to the different positions of azobenzene units in the polymers, it is divided into side‐chain, main‐chain, and alternative‐type polymers. The chemical structures of obtained polysiloxanes are confirmed by nuclear magnetic resonance spectra and mass spectra. Three polymers present high thermal decomposition temperatures and the medium glass transition temperatures. The effects of polymeric structures on the second‐order nonlinear properties are compared. The main‐chain polysiloxane possesses the highest thermal stability because of its rigid architecture. The side‐chain polysiloxane shows the fastest isomerization transformation rate due to the large free volume. Besides, the alternative polysiloxane displays the best second‐order nonlinear performance with second harmonic generation coefficient (d33) value of 47.6 pm V−1, which is 3 times higher than the side‐chain one. [ABSTRACT FROM AUTHOR]

Recycling coal-based waste (CBW) into composites suitable as a building material might be a necessary response to combat its risk to the environment. Therefore, the objective of this study was to investigate the microstructure and performance of coal composites produced from CBW and polysiloxane polymer (SPR-212). Four types of CBW that differ in physicochemical properties were examined. Fourier transform infrared spectroscopy results indicated that the higher the intensity of the C=C bonds in the CBW, the higher the pyrolysis mass loss and shrinkage experienced by the composites during pyrolysis. The continuous operating temperature of the composites is up to 600 °C. However, at temperatures above 600 °C, composites containing carbon content greater than 36% manifested dramatic degradation. Pyrolysis mass loss in the range of 5.28 to 29.62% was obtained for all the composites. The density range of the composites is between 1.5 and 1.9 g per cubic centimetre. The water absorption of all the composites is within the range of 0 to 25% and is comparable to many building materials. Notably, the composites containing total carbon less than 10% registered a water contact angle greater than 90°, indicating the low wettability of their surface. Furthermore, composites that embodied the highest total carbon (63%) displayed the worst structural property. The findings of this study lay the foundation for further development of high-quality structural coal composites from CBW and the SPR-212 preceramic polymer through optimisation of the processing conditions. [ABSTRACT FROM AUTHOR]

The effects of Cu2O nanoparticles (Cu2O NPs) modified with 3-(trimethoxysilyl)propyl methacrylate (TMSPM) (m-Cu2O NPs) on the properties of a polysiloxane (PS) coating were investigated. The organic surface modifications improved the antimicrobial activity of the Cu2O NPs and their dispersion in a PS matrix. Due to the broad dispersion of the m-Cu2O NPs, the PS/m-Cu2O coating exhibited better mechanical properties and better thermal stability than unmodified Cu2O (u-Cu2O) coatings. The onset temperature of PS/m-Cu2O was 24 °C higher than that of the neat PS coating and 11 °C higher than that of the PS/u-Cu2O coating. The PS/m-Cu2O coating exhibited high antibacterial activity for sulfate-reducing bacterial strains, but the PS/m-Cu2O coating showed slight bacterial inhibition of Pseudomonas stutzeri B27 bacteria (which were isolated under seawater at Phu Quoc Island, Kien Giang Province, Vietnam). Biofilm inhibition by the PS coatings with and without the m-Cu2O NPs was also tested with a natural seawater immersion test. After a 60-day test, the biofilm formed on the PS coating surface was ten times thicker than that on the PS/m-Cu2O coating. Fourier transform infrared spectroscopy (FTIR) data and the surface properties of the coating indicated that immersion in natural seawater insignificantly affected the functional groups of the coating but had a substantial influence on the smoothness of the coating, which made the surface of the coating more hydrophilic. These results suggested that the PS/m-Cu2O could be used as an antifouling coating for the marine industry. [ABSTRACT FROM AUTHOR]

As reported herein, a novel addition‐type liquid silicone rubber (LSR)/red mud (RM) composite has been synthesized. Triethoxyvinylsilane (KH151) was used as a surface modification agent to treat RM and form hydrophobic surfaces. The optimal formulation of the composite was determined by the mechanical properties of the LSR that were prepared at different crosslinker and filler contents. The reinforcement mechanism of modified RM on LSR was revealed by combining Fourier transform infrared (FTIR) spectroscopy, x‐ray photoelectron spectroscopy and mechanical property tests. Thermal degradation behavior of RM/LSR at elevated temperature was investigated by the thermogravimetric analysis (TG), TG‐FTIR and alteration of mechanical properties after thermal aging. The results of the experiment indicate that modified RM increased the tensile strength and Young's modulus of LSR dramatically and provides superior thermal stability to the LSR. With 100 phr RM added, the tensile strength of RM/LSR composite was almost 12 times greater than that of pure LSR, and pure LSR degrades completely after aging at 300°C for 24 h while RM/LSR retains its mechanical properties. [ABSTRACT FROM AUTHOR]

Organosilicon polymers (silicones) are an important part of material chemistry and a well-established commercial product segment with a wide range of applications. Silicones are of enduring interest due to their unique properties and utility. Recently, new application areas for silicone-based materials have emerged, such as stretchable electronics, wearable stress sensors, smart coatings, and soft robotics. For this reason, research interest over the past decade has been directed towards new methods of crosslinking and increasing the mechanical strength of polyorganosiloxanes. The introduction of self-healing mechanisms may be a promising alternative for such high-value materials. This approach has gained both growing research interest and a rapidly expanding range of applications. Inherent extrinsic and intrinsic self-healing methods have been used in the self-healing of silicones and have resulted in significant advances in polymer composites and coatings, including multicomponent systems. In this review, we present a summary of research work dedicated to the synthesis and applications of self-healing hybrid materials containing polysiloxane segments, with a focus on antimicrobial and antifouling coatings. [ABSTRACT FROM AUTHOR]

Herein, a pohotosentive polysiloxane (PSO)/talc/Al 2 O 3 slurry was prepared for the digital light processing printing. Liquid photosensitive PSO was exploited as a triple-functioned material, acting both as the resin matrix, a high reactive Si source and a pore generator. Through adjusting the raw material components, polysiloxane can be sintered with talc and Al 2 O 3 fillers after being pyrolyzed to 1200 oC while pores with variable diameters can be generated. Ternary component slurry prepared based on the above strategy possesses the characteristics of low viscosity, high reaction activity and good homogeneity. Sintering schedule of the printed thin-walled precursor was investigated to guarantee the morphology of cordierite product was consistent with the printed model. This work aims to provide a new strategy for DLP printing of MgO-Al 2 O 3 -SiO 2 ternary and other polymer derived ceramics. [ABSTRACT FROM AUTHOR]

In this research, benzoxazine (BA-a) and diamino polysiloxane (PSX750) blends were prepared at 0–50 wt% of BA-a. The interactions between two polymeric components were investigated via a Fourier Transform Infrared Spectrometer (FT-IR). The thermal properties of the blends were also determined with Dynamic Mechanical Analyzer (DMA) and Thermogravimetric Analyzer (TGA). The mechanical properties and shape memory behaviors of the blends were also investigated. The FTIR spectra exhibited the shift of the peak from 1672 to the range of 1634–1637 cm−1, which could be identified as hydrogen bonds between two polymeric domains at the contents from 30 to 50 wt%. The DMA thermograms revealed two glass transition temperatures, which could indicate a partially miscible system. The char yield values were increased, while the decomposition temperatures were decreased with an increasing benzoxazine content. Interestingly, the blends at the contents of 10 and 20 wt% presented dual-shape memory behaviors, whereas triple- or multiple-shape memory behaviors were observed with benzoxazine contents of 30 to 50 wt%. For the high-temperature recovery state, a shape memory ratio of 97.5% with a recovery time of 65 s and a shape fixity ratio of 66.7% was recorded at the content of 50 wt%. For the low-temperature recovery state, a shape recovery ratio of 98.9% was observed at the same content. Moreover, the values of the recovery ratio for four shape-recovery cycles revealed multiple shape memory behaviors with high recovery ratios in the range of 95–98%. [ABSTRACT FROM AUTHOR]

The development of polymer-modified asphalt (asphalt = asphalt binder) is significant because the polymer modifier can improve the performance of asphalt mixture and meet the requirements of the modern asphalt pavement. Herein, we present a novel polysiloxane-modified asphalt with enhanced performance, formed by simply mixing hydroxy-terminated polysiloxane (HO-PDMS) into base asphalt at 140 °C. The interaction mechanism of HO-PDMS in base asphalt was characterized by FT-IR, GPC, and DSC. It reveals that HO-PDMS polymers have been chemically bonded into the asphalt, and, thus, the resultant asphalt exhibits optimal compatibility and storage stability. The results based on fluorescence microscopy and a segregation test prove that HO-PDMS has good compatibility with base asphalt. Moreover, by virtue of the intriguing properties of polysiloxane, the present asphalt possesses improved low- and high-temperature properties, higher thermal stability, and enhanced hydrophobicity compared to conventional asphalt when using an appropriate dosage of HO-PDMS. DSC indicated that the Tg of modified asphalt (−12.8 °C) was obviously lower than that of base asphalt (−7.1 °C). DSR shows that the rutting parameter of modified asphalt was obviously higher than that of base asphalt. BBR shows that modified asphalt exhibited the lowest stiffness modulus and the highest creep rate with an HO-PDMS dosage of 6% and 4%, respectively. These results demonstrate that polysiloxane-modified asphalt can be promisingly utilized in realistic asphalt pavement with specific requirements, particularly high-/low-temperature resistance. [ABSTRACT FROM AUTHOR]

Hydrophobic materials possess exceptional properties, making them extensively useful in daily production and life. However, developing low‐cost and flexible hydrophobic materials remains a challenging task. In this study, a series of composite emulsions were prepared by introducing hydroxyl‐terminated polydimethylsiloxane as a modifier into polyurethane acrylate via a solvent‐free approach. The composite emulsions were then used to fabricate polymer films using the solvent evaporation technique. The effects of varying siloxane content on the properties of composite emulsions and polymer membranes were examined. The results showed that increasing the siloxane content improved the hydrophobic properties and flexibility of the film materials. Fourier transform infrared spectroscopy confirmed the introduction of the SiOSi group into the polyurethane chain structure, the absorption peak for asymmetric stretching vibration of SiOSi is at 1100 cm−1. The mechanical properties test revealed that the film had excellent elongation at break (278.96 ± 0.01%), and a hydrophobic surface with a contact angle of 101.94° was obtained. The composite materials showed improved water resistance and thermal stability with the increase in siloxane content. The hydrophobic film is a promising material for application in decoration, architecture, and flexible wearable devices. [ABSTRACT FROM AUTHOR]

Carbon dots (CDs) as the emerging carbon‐based nanomaterials have great application potential in the optical devices and bioimaging fields. Due to their poor stability, the conventional CDs are prone to self‐quenching and their photoluminescence is untunable. Herein, the polysiloxane functionalized CDs were prepared from the solvothermal reaction between citric acid and the polysiloxanes with different aminopropyl contents aiming to improve the stability and photoluminescence of CDs. The average size of the polysiloxane functionalized CDs ranged from 2.2 to 6.4 nm. The UV–visible absorption spectra of these CDs changed from long wavelength to short wavelength with the decrease of the aminopropyl content in the polysiloxanes. The fluorescence intensities and fluorescence cores of these CDs also varied with the aminopropyl contents in the polysiloxanes, which demonstrated that the photoluminescence of the functionalized CDs could be adjusted by the aminopropyl content in the polysiloxanes. When the aminopropyl content in the polysiloxanes was 50%–75%, the polysiloxane functionalized CDs possessed relatively high fluorescence quantum yield. The polysiloxane modification can effectively improve the stability of CDs and enable the tunable photoluminescence. This study provides a new strategy for improving the performances of CDs and is of importance for promoting the practical application of CDs. [ABSTRACT FROM AUTHOR]

Nanocomposites based on Keggin-type polyoxometalate H5PV2Mo10O40 (POM) and organically modified silicate (Ormosil) were prepared by sol-gel processes. The physical properties of the Ormosil/POM composites were examined using FTIR, UV, SEM, TEM and XRD. These techniques indicated that the POM was bond to the Ormosil matrix after impregnation. The antibacterial effects of Ormosil/POM and the Ormosil+POM were assessed by the zone of inhibition, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). A higher POM proportion used in the Ormosil/POM yielded a stronger antimicrobial effect that was superior to Ormosil+POM. The excellent antibacterial performance of Ormosil/POM-10 compositean was discovered. Ormosil/POM composites were therefore believed to have great potential for use as an antibacterial material. Highlights: The POM was chemically bonded to the carrier to solve the problem of separation. The original structural characteristics of Ormosil and POM remained unaffected. The addition of more POM led to a stronger interaction force with SiO2. A higher POM proportion used in the Ormosil/POM yielded a stronger antimicrobial effect. [ABSTRACT FROM AUTHOR]

Functionalization of polyolefins has been a challenging but promising issue since their invention, with the promise of retaining inherent properties and overcoming the low reactivity and poor compatibility. Organosilicons are widely used for polymer modification to improve thermal stability, hydrophobicity, compatibility, and permeability. Since the advent of alkoxysilane‐grafted polyethylene in 1960s, organosilicon‐functionalized polyolefins (Si‐PO) have been extensively prepared, investigated, and developed. The structure of Si‐PO is designable due to the flexible chemistry of organosilicons; crosslinked, long chain branched, and star‐shaped polyolefins are available after the introduction of alkoxysilanes, chlorosilanes, hyrdosilanes, or alkylsilanes into polyolefins, and generally these polymers are more compatible to fillers than commercial polyolefins due to stronger interaction. In addition, functionalization of polyolefins with stable organosilicon components such as polysiloxane and polysilsesquioxane can improve thermostability, hydrophobicity, gas permeability, and aging resistance; such polyolefins are usually grafted or block polymers. In this review, Si‐PO is classified according to the functional organosilicon component, namely alkoxysilane, chlorosilane, hydrosilane, alkylsilane, polysiloxane, and polysilsesquioxane; their preparations are discussed minutely and summarized with manifold examples. Silicon‐containing structures impart the unique properties of organosilicons to polyolefins; applications of Si‐PO as compatibilizers, processing aids, battery separators, and separating membranes have been widely reported and are discussed here. [ABSTRACT FROM AUTHOR]

Polyamides are essential thermoplastics whose current worldwide annual production exceeds 10 million tons. They are ubiquitous and easily ignitable polymeric materials that require addition of flame retardants to comply with fire safety requirements for various applications. Flame retardant additives can be incorporated into polymer matrix as fillers or at the molecular level, implying use of reactive additives. The latter approach is less developed, but usually offers several advantages over adding flame-retardant fillers: lower additive loading used to achieve specific level of fire performance, no flame-retardant migration with time, lower corrosiveness, better polymer stability etc. Rendering polyamides intrinsically flame retardant is therefore highly desirable. In this review we survey progress in inherently flame-resistant polyamides done over the period from 2004 to 2020. The polymers are grouped according to their chemical structures: aliphatic, semiaromatic and aromatic polyamides, polyamidoimides and hybrid siloxane-polyamides. Their monomer preparation, synthesis details, thermal properties and fire performance are discussed. The minimal inclusion criterion for this review was reported fire-resistance performance: either V-1/V-0 rating achieved in UL-94 burning tests or experimental or calculated LOI above 23%.

Transparent polysiloxane elastomers with good self-healing and reprocessing abilities have attracted significant attention in the field of artificial skin and flexible displays. Herein, we propose a simple one-pot method to fabricate a room temperature self-healable polysiloxane elastomer (HPDMS) by introducing dynamic and reversible imine bonds and boroxine into polydimethylsiloxane (PDMS) networks. The presence of imine bonds and boroxine is proved by FT−IR and NMR spectra. The obtained HPDMS elastomer is highly transparent with a transmittance of up to 80%. The TGA results demonstrated that the HPDMS elastomer has good heat resistance and can be used in a wide temperature range. A lower glass transition temperature (Tg, −127.4 °C) was obtained and revealed that the elastomer is highly flexible at room temperature. Because of the reformation of dynamic reversible imine bonds and boroxine, the HPDMS elastomers exhibited excellent autonomous self-healing properties. After healing for 3 h, the self-healing efficiency of HPDMS reached 96.3% at room temperature. Moreover, the elastomers can be repeatedly reprocessed multiple times under milder conditions. This work provides a simple but effective method to prepare transparent self-healable and reprocessable polysiloxane elastomers.

Current research on materials engineering focuses mainly on bio-based materials. One of the most frequently studied materials in this group is polylactide (PLA), which is a polymer derived from starch. PLA does not have a negative impact on the natural environment and additionally, it possesses properties comparable to those of industrial polymers. The aim of the work was to investigate the potential of organosilicon compounds as modifiers of the mechanical and rheological properties of PLA, as well as to develop a new method for conducting mechanical property tests through innovative high-throughput technologies. Precise dosing methods were utilized to create PLA/silicone polymer blends with varying mass contents, allowing for continuous characterization of the produced blends. To automate bending tests and achieve comprehensive characterization of the blends, a self-created workstation setup has been used. The tensile properties of selected blend compositions were tested, and their ability to withstand dynamic loads was studied. The blends were characterized through various methods, including rheological (MFI), X-ray (XRD), spectroscopic (FTIR), and thermal properties analysis (TG, DSC, HDT), and they were evaluated using microscopic methods (MO, SEM) to examine their structures.

ABSTRACTNatural fibers can be an effective filling of composites and improve their properties. The aim and novelty of the research was to investigate the effect of modifying natural fibers with silanes and, especially synthesized, polysiloxanes with various functional groups in combination with alkali treatment on the properties of composites based on polylactic acid. For this purpose, composites with a 20% content of flax fibers were produced. Scanning electron microscopic (SEM) tests of the composites showed that the modification of the fibers had a positive effect on the adhesion to the polymer. Their thermal stability (TGA) was slightly improved by the addition of modified fibers, especially by polysiloxane with long alkyl chain. Flammability (PCFC) of composites was also improved up to 36% HRR reduction for mercerized fibers. The mechanical properties of the composites were tested on the basis of a tensile test. It has been shown that properly modified flax fibers can be a good filling for biocomposites, and especially synthesized polysiloxanes used to modify can be more effective than silanes.

To harness the synergistic effect of different polymer chains, poly(methyl(2‐(tris(2‐H methoxyethoxy)silyl)ethyl)siloxane)) grafted with Si‐tripodant centers (2550EO) known for their flexible structure was physically blended with poly(vinylidene fluoride‐co‐hexafluoropropylene (PVdF‐HFP). Here, 2550EO containing varying amounts of amide salts (LiF(SO2CF3)2 (LiTFSI)) was used as the main matrix. PVdF‐HFP was used in concentrations of up to 30 % to increase the film‐forming ability of 2550EO/LiTFSI, and a series of solid polymer electrolyte (SPE) membranes were prepared. After incorporating the blended SPE with a minute amount of organic carbonates (only 15 wt%), the electrochemical features, such as Li+ conductivity and transference number (tLi+), significantly increased. For example, a tLi+ of 0.42 and ionic conductivities of 0.64 and 0.3 S cm−1 at 60 °C and 25 °C, respectively, were achieved. In addition, the electrochemical stability exceeded 5 and 4.8 V at 25 °C and 60 °C, respectively. Thus, a high Li/LiFePO4 battery performance with high coulombic efficiencies exceeding 96 % and 98 % at 60 °C and 25 °C were achieved at 0.1 C, respectively. This was due to the superiority of the polysiloxane structure over its organic counterpart, attributed to its highly flexible backbone, high segmental mobility, and outstanding thermal and chemical stability. [ABSTRACT FROM AUTHOR]

In this paper, five different solvent-borne industrial topcoats were dried with infrared (IR) radiation and under atmospheric conditions. A comparison of physical, mechanical, chemical, and electrochemical properties of differently dried topcoats was made. The results of differential scanning calorimetry (DSC), Fourier-Transform Infrared Spectroscopy (FTIR), and adhesion of a topcoat to the metal substrate (determined by the pull-off test) indicate a higher degree of crosslinking of examined topcoats, which improves the coating's protective properties. Scratch hardness was determined by the pencil hardness test. Impact resistance was examined with a falling-weight test. Changes in the shade of the coating were examined by visual inspection and using a gloss meter. The electrochemical measurements of open circuit potential (OCP) and electrochemical impedance spectroscopy (EIS) were conducted. The thermal stability of topcoats was tested by thermogravimetric analysis (TGA). The results show overall better properties of IR-dried topcoats. In addition, topcoats dry significantly faster when IR radiation is applied, which makes this drying method very interesting for industrial application. [ABSTRACT FROM AUTHOR]

Herein, a compound has been developed via melt blending and curing of poly(styrene–ethylene butylene–styrene) triblock copolymer (SEBS) with silicone rubber (SR). The cure characteristics, mechanical, thermal, and dynamic mechanical properties of the SR/SEBS blends of different mass ratios (100/0, 90/10, 75/25, 50/50, 25/75, and 0/100) are investigated. The cure characteristics reveal that the crosslinking and cure rate of SEBS are lower than SR. The cure rate of SEBS is 0.35 dN.m/min, while it is 15.35 dN.m/min for SR. Also, in the blends, as the content of SR increased, the crosslinking and cure rate of the blends show an upward trend. The results of mechanical properties indicate that the presence of SEBS with a formed (simultaneously physical and chemical) double network can strengthen the mechanical properties of SR, as the tensile strength and elongation at break of the blends improve by increasing the content of SEBS. It is found that adding 25% of SEBS to SR enhances the tensile strength and elongation at break of the SR blend from 5.66 to 7.56 MPa and from 116 to 185%, respectively. Thermogravimetry demonstrates the better thermal stability of SR than SEBS and the blends. The obtained primary thermal parameters reveal that the thermal stability of the SEBS phase in the blends improves with growing the SR content. Dynamic mechanical thermal analysis exhibits two loss tangent peaks for SEBS at 119.61 and − 45.36 °C, which are related to the glass transition temperatures of polystyrene (as a physical crosslinker phase) and ethylene–butylene blocks, respectively. Also, two peaks are observed for SR at − 37.16 and − 134.16 °C. Differential scanning calorimetry confirms that the two temperatures are related to the melting and glass transition temperatures of SR, respectively. [ABSTRACT FROM AUTHOR]

An polysiloxane containing imide ring was synthesized by the reaction of bisphenol A diether diene (BPADAAA) with 1,1,3,3-tetramethyldisiloxane under the action of speier catalyst. The polysiloxane containing imide ring with special POSS structure was prepared by the reaction of imide ring silane coupling agent (BPADA-AA-TES) with water. The structure and performance of the two polysiloxanes were characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analyzer (TG) and differential scanning calorimeter (DSC). The results show that the glass transition temperature (Tg) of polysiloxane containing imide ring is 251 °C, and the 10% decomposition temperature (Td10%) is 474 °C. The Tg and Td10% of polysiloxane containing imide ring with POSS structure are 211 °C and 452 °C, respectively. The thermal performance of polysiloxane containing imide ring are better than those of polysiloxane containing imide ring with POSS structure. The synthesized polysiloxane containing imide ring has good thermal performance and can be used as a coating material for in-situ polymerization process. [ABSTRACT FROM AUTHOR]

Dye-sensitized solar cells (DSSCs) are a very promising solution as remote sustainable low power sources for portable electronics and Internet of Things (IoT) applications due to their room-temperature and low-cost fabrication, as well as their high efficiency under artificial light. In addition, new achievements in developing semitransparent devices are driving interest in their implementation in the building sector. However, the main obstacle towards the large-scale exploitation of DSSCs mainly concerns their limited long-term stability triggered by the use of liquid electrolytes. Moreover, the device processing generally involves using a thick adhesive separator layer and vacuum filling or injection of the liquid polymer electrolyte between the two electrodes, a method that is difficult to scale up. This review summarizes the advances made in the design of alternative (quasi-)solid polymer electrolytes, with a focus on polysiloxane-based poly(ionic liquid)s. Their behavior in full DSSCs is presented and compared in terms of power generation maximization, advantages and shortcomings of the different device assembly strategies, as well as polymer electrolyte-related processing limitations. Finally, a fair part of the manuscript is allocated to the assessment of liquid and gel polymer electrolyte printability, particularly focusing on polysiloxane-based electrolytes. Spray, blade (slot-dye), screen and inkjet printing technologies are envisaged considering the polymer electrolyte thermophysical and rheological properties, as well as DSSC processing and operating conditions. [ABSTRACT FROM AUTHOR]

Polysiloxane is widely used in biomedical applications because of its good biocompatibility and excellent micro and nano-scale processability. Using PubMed and Citex's data analysis platform, this paper examines polysiloxane research and compares its development history from 2002-01 to 2021-12. Research hotspots, keyword analysis, and the number of papers published on polysiloxane in biomedicine are used in this study to analyze and discuss the current status of polysiloxane research in biomedicine. Over the last twenty years, there has been a significant surge in the number of publications related to the use of polysiloxane in biomedicine. This trend highlights the growing intersection and collaboration between the fields of polymeric material science and biomedical disciplines. Therefore, statistics about the number of papers on polysiloxane and the frequency of hot words are valuable resources for biomedical research and development. [ABSTRACT FROM AUTHOR]

Amphiphilic copolymer self-assembly is a straightforward approach to obtain responsive micelles, nanoparticles, and vesicles that are particularly attractive for biomedicine, i.e., for the delivery of functional molecules. Here, amphiphilic copolymers of hydrophobic polysiloxane methacrylate and hydrophilic oligo (ethylene glycol) methyl ether methacrylate with different lengths of oxyethylenic side chains were synthesized via controlled RAFT radical polymerization and characterized both thermally and in solution. In particular, the thermoresponsive and self-assembling behavior of the water-soluble copolymers in water was investigated via complementary techniques such as light transmittance, dynamic light scattering (DLS), and small-angle X-ray scattering (SAXS) measurements. All the copolymers synthesized were thermoresponsive, displaying a cloud point temperature (Tcp) strongly dependent on macromolecular parameters such as the length of the oligo(ethylene glycol) side chains and the content of the SiMA counits, as well as the concentration of the copolymer in water, which is consistent with a lower critical solution temperature (LCST)-type behavior. SAXS analysis revealed that the copolymers formed nanostructures in water below Tcp, whose dimension and shape depended on the content of the hydrophobic components in the copolymer. The hydrodynamic diameter (Dh) determined by DLS increased with the amount of SiMA and the associated morphology at higher SiMA contents was found to be pearl-necklace-micelle-like, composed of connected hydrophobic cores. These novel amphiphilic copolymers were able to modulate thermoresponsiveness in water in a wide range of temperatures, including the physiological temperature, as well as the dimension and shape of their nanostructured assemblies, simply by varying their chemical composition and the length of the hydrophilic side chains. [ABSTRACT FROM AUTHOR]

In this article, three polymerizable polysiloxane monomers with different chain lengths (MA-Sin, n = 3,6,9) have been synthesized, and then MA-Sin was mixed with disulfide monomer (SA) and different acrylate monomers in certain proportion to obtain a series of photopolymerizable systems. The effects of the contents of SA and MA-Sin, and the chain length of MA-Sin on the photopolymerization kinetics, volume shrinkage, water contact angle, thermal resistance, glass transition temperature (Tg), tensile properties and degradability of the photocured films were explored in detail. The results show that the content and the chain length of MA-Sin have no significant effect on the final double bond conversion, which reaches about 94%. With the increase of SA content, the volume shrinkage of the photocured film descends and eventually drops to 3.23%. The addition of MA-Sin contributes to improve thermal stability and hydrophobicity. With the lengthening of the chain length of MA-Sin, the water contact angle, tensile strength, elongation at break and thermal resistance of the photocured film were enhanced, whereas Tg is decreased. More importantly, the SA endows the photocured films with good degradability. The acrylate photopolymerization systems containing disulfide monomer (SA) and polysiloxane monomer (MA-Sin, n = 3,6,9) exhibit excellent photopolymerization property, low volume shrinkage (3.42%), outstanding degradation property, and improved thermostability and hydrophobicity. [ABSTRACT FROM AUTHOR]

The Silres H62C methyl-phenyl-vinyl-hydrogen polysiloxane is a promising candidate as a SiC precursor for 3D printing based on photopolymerization reaction. An in-depth nuclear magnetic resonance spectroscopy analysis allowed us to determine its structure and quantify its functional groups. The polysiloxane was found to have a highly branched ladder-like structure, with 21.9, 31.4 and 46.7% of mono-, di- and tri-functional silicon atoms. The polysiloxane cross-links from 180 °C using hydrosilylation between silyl groups (8.4% of the total functional groups) and vinyl groups (12.0%) and contains a non-negligible ethoxy content (2.4%), allowing cross-linking through a hydrolyze/condensation mechanism. After converting the polymer into ceramic and thus releasing mainly hydrogen and methane, the ceramic yield was 72.5%. An X-ray diffraction analysis on the cross-linked and pyrolyzed polysiloxane showed that the ceramic is amorphous at temperatures up to 1200 °C and starts to crystallize from 1200 °C, leading into 3C-SiC carbon-rich ceramic at 1700 °C in an argon atmosphere.

Cotton fabrics are popular for their excellent properties, but their wider application is always limited due to their disadvantages including lack of water repellency and easy pollution. In this paper, based on improving environmental protection and the durability of water repellent, an organic-inorganic nano-hybrid cross-linked polysiloxane was prepared by chemical compounding method and emulsified to get water repellent. The water repellent finishing of cotton fabrics was carried out using the pad-dry-cure process, and the effect of finishing conditions on the water contact angle (WCA) of fabrics was investigated. Furthermore, the finishing process was optimized by the central composite design (CCD)-response surface method (RSM). The results show that the significant order of factors affecting the WCA of cotton fabric finished is successively finishing agent concentration > curing temperature > curing time. The established model has high prediction accuracy and the best finishing conditions are finishing concentration 89 g/L, curing temperature 162°C, curing time 130 s, response prediction value Y = 149.5°, which is very close to the experimental value of 149.7 ± 0.5°.