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Nanoparticles have aroused widespread interest because of their unique surface structure and nano effect, which presents novel characteristics like as sound, light, electricity, magnetism, and thermal properties. However, two critical defects have hindered their applications: (1) poor processability resulting from the high melting temperature (e.g., >1000 °C) for some inorganic nanoparticles; (2) the restriction of the nano effect caused by the easy aggregation of the nanoparticles. To solve those issues, solvent-free nanofluids (SNFs) with hard cores and flexible organic chains were successfully designed and fabricated at the beginning of the twenty-first century. The promising technology of SNFs not only solved the dispersion problem of nanomaterials but also imparted novel functionalization to nanoparticles. Up to now, many researchers have been devoted to developing diverse cores and flexible organic polymer chains to endow SNFs with particular functions, such as conductivity, fluorescence, lubricity, and so on. However, there are few review reports on the research progress in the fabrication and applications of functional SNFs. To gain a better understanding of SNFs, this paper presents an overall investigation into the development, fabrication, as well as the applications of functional SNFs.

Although high-thermal conductivity fillers can enhance the thermal conductivity of organic phase change materials (PCMs), it is still difficult to simultaneously prevent the loss in latent heat. The realization of enhanced thermal conductivity without adversely affecting the latent heat of polymeric PCMs remains challenging. We report experimental results demonstrating that polyethylene glycol (PEG)-based PCM composites exhibit large latent heats beyond the expected values and significantly improved thermal conductivities. Latent heat and thermal conductivity enhancements are achieved by optimizing the interaction between the filler and PCM in the PEG/graphene oxide (GO) composites. PEG-grafted GO (PEG-g-GO) is synthesized and introduced into the PEG to regulate the interaction between the PEG base and GO. The result can be largely attributed to the enhanced GO dispersion and heightened mobility of the PEG chains. The grafted PEG in the PEG-g-GO acts as a plasticizer, leading to a considerable effect on the crystallization kinetics of the PEG in the composite PCMs, and thus the improved crystallizability. Graphical abstractLatent heat and thermal conductivity enhancements are achieved by optimizing the interaction between the filler and PCM in the PEG/GO composites.

Flexible polymer dielectrics for capacitive energy storage that can function well at elevated temperatures are increasingly in demand for continuously advancing and miniaturizing electrical devices. However, traditional high-resistance polymer dielectrics composed of aromatic backbones have a compromised band gap (Eg) and hence suffer from low breakdown strength and a huge loss at high temperatures. Here, based on the density functional theory (DFT) calculations, rigid and non-coplanar alicyclic segments are introduced into the polyimide backbone to overcome the incompatibility of a high glass transition temperature (Tg) and large Eg. Thanks to the large optical Eg(∼4.6 eV) and high Tg(∼277 °C), the all-alicyclic polyimide at 200 °C delivers a maximum discharge energy density (Ue) of 5.01 J cm−3with a charge–discharge efficiency (η) of 78.1% at 600 MV m−1, and a record Ueof 2.55 J cm−3at η= 90%, which is 10-fold larger than that of the state-of-art commercial polyetherimides (PEIs). In addition, compared with aromatic polyimides, the all-alicyclic polyimide possesses a better self-clearing characteristic due to a smaller ratio of carbon to hydrogen and oxygen, which facilitates its long-term reliability in practical applications.

Electronic skin has aroused extensive research interest due to high similarity with human skin. Realizing a multifunctional electronic skin that is highly consistent with skin functions and endowed with more other functions is now a more urgent need and important challenge. Here, we use 2,2,6,6-tetramethylpiperidinyl-1-oxyl (TEMPO)-oxidized cellulose nanofibril (TOCN) dispersion and highly conductive Ti3C2TXdispersion to prepare TOCN/Ti3C2TXcomposite film through vacuum-assisted filtration. The obtained composite film imitating the nacre-like lamellar structure of natural shells has good mechanical properties (124.6 MPa of tensile strength). Meanwhile, the composite film also showed excellent electromagnetic shielding performance (36 dB), biocompatibility, and antibacterial properties. In addition, the piezoresistive sensor assembled from the composite film exhibited a high sensitivity (11.6 kPa–1), fast response and recovery time (≤10 ms), ultralow monitoring limit (0.2 Pa), and long-term stability (>10 000 cycles). It also could detect human daily activities such as finger bent, chewing, and so on.

Powdery mildew, caused by the biotrophic fungus Blumeria graminisf. sp. tritici(Bgt), is a global disease that poses a serious threat to wheat production. To explore additional resistance gene, a wheat-Dasypyrum villosum1V#5 (1D) disomic substitution line NAU1813 (2n = 42) with high level of seedling resistance to powdery mildew was used to generate the recombination between chromosomes 1V#5 and 1D. Four introgression lines, including t1VS#5 ditelosomic addition line NAU1815, t1VL#5 ditelosomic addition line NAU1816, homozygous T1DL·1VS#5 translocation line NAU1817, and homozygous T1DS·1VL#5 translocation line NAU1818 were developed from the selfing progenies of 1V#5 and 1D double monosomic line that derived from F1hybrids of NAU1813/NAU0686. All of them were characterized by fluorescence in situhybridization, genomic in situhybridization, 1V-specific markers analysis, and powdery mildew tests at different developmental stages. A new powdery mildew resistance gene named Pm67was physically located in the terminal bin (FL 0.70–1.00) of 1VS#5. Lines with Pm67exhibited seedling stage immunity and tissue-differentiated reactions at adult plant stage. The sheaths, stems, and spikes of the Pm67line were still immune, but the leaves showed a low degree of susceptibility. Microscopic observation showed that most penetration attempts were stopped in association with papillae on the sheath, and colonies cannot form conidia on the susceptible leaf of Pm67line at adult plant stage, suggesting that the defence layers of the Pm67line is tissue-differentiated. Thus, the T1DL·1VS#5 translocation line NAU1817 provides a new germplasm in wheat breeding for improvement of powdery mildew resistance.

Abstract: Self-healing elastomer materials were successfully synthesized from ureido-pyrimidinone (UPy)-modified polydimethylsiloxane (PDMS) mixing with organic montmorillonite (OMMT) and C22 alkyl toluene sulfonic acid (ATS)-doped polyaniline (PANI-ATS) in this work. The structure, thermal properties, and self-healing properties were investigated. The results demonstrated that hydrogen bonds formed in the self-healing elastomer materials and they exhibited good thermal property and self-healing at both macro and micro levels. The strength after healing was up to 0.8 MPa, three times bigger than the original PDMS. OMMT and PANI-ATS works together to enhance PDMS without damaging its self-healing ability, thus extending the application scope of PDMS. Graphic abstract:

High capacity Fe3O4-based anode materials have attracted a great deal of attention as an alternative to commercial graphite in Li-ion batteries (LIBs). However, it is still a challenge to alleviate the fast capacity fading of Fe3O4due to the intercalation of Li+. In this work, we develop a novel and effective strategy to rapidly fabricate the hollow Fe3O4nanostructures via the solvent-induced effect. The influence of the ratio of the tert-butanol (TB) and the water on the microstructure was further discussed. As expected, when the hollow nanostructures based on the 1:1 ratio of TB and water is used as the anode material for LIBs, a high reversible capacity of 1020 mA h g−1after 100 cycles at 1 A g−1and 450 mA h g−1even for 5 A g−1after 1000 cycles can be obtained, paving a new avenue to fabricate the functionally hollow nanostructures for high-performance anode materials or other applications.

Porous functionalized silica nanoparticles have attracted the interest of researchers as they are excellent carriers for antibacterial drug delivery applications. In this work, porous aminated-silica nanoparticles (SiO 2 -NH 2 NPs) were prepared via one-step approach through the ammonia-catalyzed hydrolysis of tetraethylorthosilicate (TEOS) and (3-aminopropyl) triethoxysilane (APTES) in a mixed water–ethanol system. The obtained SiO 2 -NH 2 NPs displayed a spherical morphology and relatively uniform size distribution, while the morphology and structure of SiO 2 -NH 2 NPs were mainly determined by the order of the reagents added and the pH value of the solution. After characterization, the results showed that there were a large number of –NH 2 groups on the surface of porous SiO 2 -NH 2 NPs and that the porous SiO 2 -NH 2 NPs had a large surface area of 476 m² g−1 with an average pore width of 4.3 nm. Through an absorbing–releasing experiment and bacterial test, those SiO 2 -NH 2 NPs were found to exhibit efficient absorption and release of drugs as well as a pH-dependent release pattern of epirubicin-loaded SiO 2 -NH 2 NPs. Meanwhile, SiO 2 -NH 2 @capsaicin NPs exhibited antibacterial properties. Those porous SiO 2 -NH 2 NPs could be a candidate for drug delivery for antibacterial applications owing to their tailored porous structure and high surface area. [ABSTRACT FROM AUTHOR]

High-performance dielectric nanomaterials have received increasing attention due to their important applications in the field of energy storage. Among various dielectric materials, polymer nanocomposite is one of the most promising candidates. However, the problems of environmental pollution caused by polymer-based dielectric materials have been extensively studied in recent years, which need to be solved urgently, leading to the search for new biodegradable dielectric materials. Herein, we report composite materials based on biodegradable and renewable chitin and molybdenum disulfide (MoS2) nanosheets for the first time. The MoS2nanosheets were first fabricated by glycerol/urea system and then KOH/urea aqueous solution was used to directly dissolve chitin at low temperature together with the dispersion of the MoS2nanosheets in a simple green process. The two-dimensional MoS2nanosheets possess high polarization strength, and a large specific surface area can enhance the interfacial polarization with chitin; meanwhile, it can serve as a charge breakdown barrier to hinder the propagation of electrical tree branches. The results also show that the dielectric constant and breakdown strength of the chitin/MoS2nanocomposites were increased, while the dielectric loss remained low. When the MoS2content was 5 wt %, the charge and discharge efficiencies of the composite film were more than 80%, and the breakdown strength also reached 350 MV m–1, thus resulting in a high discharge energy density of 4.91 J cm–3, which was more than twice of the neat chitin (2.17 J cm–3). Furthermore, the nanocomposite films exhibited good thermal stability. Therefore, these chitin-based nanocomposite films are promising as high-performance biomass-based dielectric capacitors.

A broadband and lightweight microwave absorber has attracted soaring research interest because of the increasing demand for electronic reliability and defense security. Lightweight ferrites/graphene porous composites with abundant interfaces are potential high-performance absorbers owing to their balanced attenuation ability and impedance matching. Herein, we synthesized hierarchical CoFe2O4/reduced graphene oxide (CFO/rGO) nanocomposites with a porous structure via an in situ solvothermal method. The electromagnetic parameters of CFO/rGO nanocomposites can be well-adjusted by modulating the weight fraction of rGO. The hierarchical porous structure and proper electromagnetic parameters result in the enhancement of impedance matching and attenuation ability. Benefiting from the controllable composition, hierarchical porous structure, and strong synergetic effect between CFO and rGO sheets, as expected, CFO/rGO nanocomposites exhibit superior microwave absorption performance with an ultrabroad bandwidth reaching 5.8 GHz (8.3–14.1 GHz) with a thin thickness of 2.8 mm. Meanwhile, a strong reflection loss of −57.7 dB at the same thickness is achieved. Considering the outstanding microwave absorption performance, the hierarchical CFO/rGO porous nanocomposites can be employed as a high-performance microwave absorber.

High-temperature energy storage performance of traditional polymer dielectrics is insufficient due to the mutual constraints of glass transition temperature (Tg) and bandgap (Eg), making them challenging to meet the demands of harsh environmental applications. In this work, in conjunction with density functional calculations (DFT), we employed the trifluoromethyl (CF3) substituent strategy to develop a heat-resistant aromatic polyimide dielectric (6FDA/TFMB) with a high Tgof 329 °C of and a large Egof 3.6 eV. The introduction of the CF3group, reducing molecular conjugation and increasing intermolecular spacing, renders the solution-cast 6FDA/TFMB film colorless and transparent. It exhibits remarkable Weibull breakdown strength (Eb) values of 578 MV m−1and 452 MV m−1at 150 °C and 200 °C, respectively. Moreover, 6FDA/TFMB achieves an energy density (Ue) of 3.21 J/cm3with an efficiency (η) of 84 % at 150 °C and a Ueof 2.42 J/cm3with an ηof 82 % at 200 °C, which outperforms most existing heat-resistant polymer dielectrics. Additionally, 6FDA/TFMB demonstrates excellent fatigue resistance and self-healing ability. This study provides a promising and cost-effective approach for developing high-performance flexible dielectrics capable of withstanding extreme thermal and electric field conditions.

Rechargeable aqueous zinc-ion batteries (AZIBs) are the most promising candidates for the energy storage due to their high safety, rich resources, and large specific capacity. However, AZIBs using neutral or slightly acidic electrolytes still face side effects and zinc dendrites on the anode surface. To stabilize the Zn anode, a chemically stable and multi-functional coating of polyvinylidene fluoride (PVDF) and 4,4′-(hexafluoroisopropylidene)diphthalic anhydride (6FDA) was prepared on the Zn surface. The anhydride groups in 6FDA can improve the hydrophilicity, promoting the migration of zinc ions. Besides, PVDF is compatible with 6FDA because of the presence of organic F-containing groups, which can also effectively reduce the nucleation overpotential and exhibit the dendrite-free Zn deposition/stripping. The PVDF/6FDA@Zn symmetric cell can cycle for 5000 h at a current density of 0.5 mA·cm−2, maintaining the extremely low polarization voltage and overpotential of 28 and 8 mV, respectively. The PVDF/6FDA@Zn∥MnO2full cell can remain a specific capacity of ∼90 mAh·g−1after 2000 cycles at 1.5 A·g−1. This simple method achieves a reversible Zn anode, providing an inspiring strategy for ultra-long-cycle AZIBs.

The low energy density of supercapacitor (SC) is considered as a major challenge for its use in intermittent renewable energy, smart grid and electric vehicles. General, those materials with high and low redox potentials are used as positive and negative electrodes respectively to fabricate asymmetric SC for higher voltage and energy density. The voltage and energy density of symmetrical SCs are usually lower than that of asymmetric SCs. This work uses a hydrothermal method to prepare reduced graphene oxide/polythiophene (RGO/Pth) aerogel with liquid-like polythiophene (L-Pth) as a precursor. The de-doping of L-Pth and π - π effect between Pth and graphene in hydrothermal process result in uniform dispersion of Pth on graphene. An aerogel with a specific surface area of 147.6 m2/g and a pore volume of 0.64 cm3/g was obtained. The RGO/Pth aerogels exhibits an oxidation potential up to 4.2 V (vs. Li/Li+potential) attributed to the P-type doping of Pth (Pth + xPF6−↔ Pthx+(PF6−)x + xe−) and a reduction potential as low as 0.6 V corresponding to the N-type doping of Pth (Pth + xLi++ xe−↔ Pthx-(Li+)x). Thus, the assembled RGO/Pth//RGO/Pth symmetrical SC shows an high-voltage of 3.6 V, an energy density of 66.1 Wh/kg at a power density of 900 W/kg and a capacitance retention of 80.2 % over 8000 cycles.

Composites of polytriphenylamine (PTPA), its novel derivative poly(4-carbamoyl-N,N-diphenylaniline-2,2,5,5-tetramethyl-pyrrolin-1-oxyl) (PTPA-PO), and multiwalled carbon nanotubes (CNTs) were synthesized by in situ polymerization. The characterization results showed that the CNTs were homogeneously distributed in the polymer matrix and formed a cross-linked conductive network. The electrical properties of PTPA/CNT composites were better than those of traditional acetylene black as conductive agents. Electrochemical tests showed that the initial specific discharge capacity of the PTPA/CNT composites was 107.6 mAh g–1(theoretical capacity of PTPA is 109 mAh g–1). Furthermore, further research to increase the specific capacity demonstrated that the as-synthesized polytriphenylamine derivative, PTPA-PO, with a CNT cathode presented two well-defined plateaus and an enhanced discharge capacity of 139.3 mAh g–1. Additionally, the PTPA-PO/CNT electrode showed superior cycling performance and remained above 90% of the initial capacity after 100 cycles. The enhanced electrochemical performance of PTPA-PO was due to its combination of the conducting polymer PTPA and free radical active site pendant PO, which increased its electrochemical reaction rate, and this composite is a promising material for high-performance polymer-based organic batteries.

Abstract

Incorporating natural product antifoulants (NPAs) into coatings with controlled surface topography is considered a promising way to suppress marine fouling. However, the rapid leakage of NPAs and the relatively complicated process of constructing well-patterned topography remain unresolved problems for practical applications. In this work, capsaicin bonded to CoFe2O4/gelatin magnetic nanoparticles was mixed with a polydimethylsiloxane (PDMS)-based block copolymer. When applied together by a simple spray-coating method, these materials formed a film. The leakage of capsaicin was restrained by the chemical bonds with the CoFe2O4/gelatin nanospheres. The primary nanorough structure was constructed by the phase separation of the PDMS-based copolymer. The secondary nanorough structure was formed by the incorporation of capsaicin-loaded CoFe2O4/gelatin nanospheres, which were demonstrated to improve the orientation of the PDMS-based block copolymer chains. The combination of oriented nanotopography and nonleaking capsaicin endows the coating with enhanced, long-lasting antifouling ability.

Lithium (Li) metal has been considered as potential choices for high-energy density batteries. However, the uncontrollable growth of Li dendrites and the infinite relative volume changes of Li anodes hinder its practical application. Herein we demonstrate a strategy to protect the Li metal anode by using a polylatic acid (PLA) nanofiber film. This polymer nanofiber film exhibits high ionic conductivity, flexibility, and chemical affinity, which enable the fast transfer of Li-ion and the feasibility to accommodate the volume changes of Li metal, and further resulting in a dendrite-free anode and stable interface. Numerous polar groups on the surface of PLA nanofibers can guide the orderly migration of Li ions. Besides, PLA nanofiber can form an artificial solid electrolyte interphase (SEI) layer by in situ reaction. Based on these advantages, we realize a high average coulombic efficiency (CE) of 95% within 150 cycles in a Li|Cu cell. When the LiCoO2cathode was assembled with PLA-protected Li anode, a high capacity retention (81%) within 100 cycles at 89mAg−1(1 C = 178mAhg−1) is obtained. This work highlights the advantages of an in situ polymer nanofiber artificial SEI layer in stabilizing Li metal anode and provides a fresh insight for the design of artificial SEI layer.

A poly(vinylidene fluoride) (PVDF) nanocomposite incorporated with polydopamine-coated reduced graphene oxide (rGO@PDOPA) nanosheets has been developed with high dielectric permittivity and low loss for electricity storage applications. Structural analysis indicates that PDOPA was successfully anchored onto rGOs through non-covalent linkage under mild conditions. The presence of PDOPA layer between rGO and PVDF can not only prevent the agglomeration and direct contact of original rGOs but also enhance the interaction between PVDF and rGO and microcapacitor formation. Compared to rGO/PVDF composites, higher dielectric permittivity and lower loss factor were achieved simultaneously in rGO@PDOPA/PVDF nanocomposites at low and moderate frequencies. The PDOPA interface layers are effective in modifying the dielectric characteristics of the composites to increase the dielectric permittivity without the introduction of loss mechanisms. This study demonstrates that PDOPA is an ideal interface layer for the development of new percolative dielectric composites with high dielectric permittivity and low loss.

Cellulose-based materials hold great promise for excellent triboelectric materials due to their fascinating attributes. However, few works have studied in a detail and systematic manner of the relationship between the cellulose structure and the output performance. Herein, we report the preparation of TEMPO-oxidized cellulose nanofibrils(TOCN) aerogel films with a high specific surface area of 134.1 m2/g as a high-performance inorganic filler-free triboelectric positive layer by a simple and controllable method. TOCN aerogel films with different structures were prepared in one-step by a direct freeze-drying process from quick freezing TOCN dispersions. The effects of four gradually increasing freezing rate methods on TOCN aerogels were proposed and studied. And the addition of TBA improved the freezing rate, reduced the volume expansion and decreased the surface tension, which were beneficial to the triboelectric properties of TOCN aerogel films. Effects of the nanofibril structures and device parameters on their triboelectric output performance were also discussed in detail. Without the addition of any fillers and chemical modification, the pure TOCN aerogel film based triboelectric nanogenerator (TENG) devices achieved a record power density of 156 mW/m2. Meanwhile, external influencing factors of the device and recyclability of the pure cellulose triboelectric material were systematically investigated. This work would provide a comprehensive guidance for the design and preparation of high-performance cellulose-based triboelectric positive materials.

Cycloolefin copolymer (COC) could be a best promising commercial polymer dielectric for metallized film capacitors at elevated temperature according to the molecular structure, but the dielectric energy storage about COC remains a huge challenge due to the lack of processing strategies of its ultrathin films. Herein, we demonstrate that COC dielectric film of around 10 μm can be fabricated by solution casting followed by uniaxial stretching and steadily service at 140 °C. Excitedly, the charge-discharge efficiency (η) of COC film is up to 97.8 % at 600 MV/m at 25 °C, which is superior to the commercially available biaxially oriented polypropylene (BOPP). Remarkably, at 140 °C, COC film exhibits a maximum discharge energy density (Ue) of 2.32 J/cm3and a ηof 85.7 %, far outperforming the heat-resistant polyimide (PI) with a maximum Ueof 1.00 J/cm3and a ηof 24.1 %. Our work provides a novel strategy for the manufacture of ultrathin COC film and could promote the commercialization of high-temperature polymer capacitor films for the energy storage.

So far, the fabrication of three-dimensional (3D) architectures of carbon nanotubes (CNTs) and graphene-based materials remains a significant challenge. In this work, one facile and template-free strategy for fabricating a novel 3D carbon hybrid architecture was reported, which is comprised of CNTs and few-layer graphene (FLG) through carbonizing the solvent-free CNT fluids at 700 °C. In this architecture, FLG served as walls and CNTs acted as backbones forming abundant chambers. The results of transmission electron microscopy, electron diffraction patterns, and Raman spectra all proved that FLG was produced from the long-chain organic ions grafted on the CNT surface through carbonization. The analysis of atomic force microscopy showed the thickness of FLG was about 1 nm. The charge–discharge experimental result of the Si/CNT–FLG battery shows that the reversible capacity still remained approximately 1350 mAh g–1with 96% capacity retention after 300 cycles at 0.5 C, demonstrating an outstanding cycling stability performance, indicating a great potential application of CNT–FLG in the lithium ion battery field.

Development of three-dimensional nanoarchitectures on current collectors has emerged as an effective strategy for enhancing rate capability and cycling stability of the electrodes. Herein, a new type of three-dimensional porous iron vanadate (Fe0.12V2O5) nanowire arrays on a Ti foil has been synthesized by a hydrothermal method. The as-prepared Fe0.12V2O5nanowires are about 30 nm in diameter and several micrometers in length. The effect of reaction time on the resulting morphology is investigated and the mechanism for the nanowire formation is proposed. As an electrode material used in lithium-ion batteries, the unique configuration of the Fe0.12V2O5nanowire arrays presents enhanced capacitance, satisfying rate capability and good cycling stability, as evaluated by cyclic voltammetry and galvanostatic discharge–charge cycling. It delivers a high discharge capacity of 293 mAh·g–1at 2.0–3.6 V or 382.2 mAh·g–1at 1.0–4.0 V after 50 cycles at 30 mA·g–1.

The commercialization of phase change materials (PCMs) based on paraffin is obstructed by the drawbacks of leakage and low thermal conductivity. Herein, we developed form-stable phase change composites via trapping paraffin into triblock copolymer. The hybrid filler, namely boron nitride and Ag-coated hollow glass microspheres (Ag@HGMs), was introduced to enhance the thermal conductivity of the composites. The latent heat values of composites could be easily tailored in a range of 157.6–192.4 J g−1by changing the loading of filler. Interestingly, the addition of boron nitride and Ag@HGMs hybrid filler has little impact on electrical insulation property, and displays a synergistic effect on the heat transfer improvement within the composites. The sample BN/Ag@HGMs-4 exhibits excellent latent heat, electrical insulation performance, thermal recycling properties and stability, and the thermal conductivity reaches up to 1.54 W m−1 K−1, which has great potential application in thermal management and heat energy collection system.

AbstractA hybrid nanocomposite material based on polystyrene-octavinyl polyhedral oligomeric silsesquioxane (PS-OV-POSS) system has been developed for safety applications requiring minimum impact resistance as well as acceptable tensile and flexural properties. The low impact resistance and sufficient tensile and flexural properties could be achieved simultaneously. The microscopic fracture mechanisms of the hybrid nanocomposite material were analyzed by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and dynamic mechanical analysis (DMA). The desired frangibility can be achieved at an exceedingly low OV-POSS level owing to the multifunctionality of OV-POSS and its rigid cubic structure. This could permit the realization of simple, low-cost low impact resistant structures without complex structure design. The material is easy to dispose by means of mechanical process due to its inherent frangible character and light weight.

The master of suspense: Self‐suspended polyaniline doped with a protonic acid containing a polyethylene glycol segment exhibits a unique thermoreversible gel‐like rheological response. Gear‐like micelles assembled by the polyaniline fibrils can mesh to form physical cross‐linking upon heating, and revert to their initial structures at lower temperatures.

The bright ideas flow: A simple extraction strategy involving quaternary ammonium salts with a poly(ethylene glycol) chain as a phase‐transfer reagent provided a route to solvent‐free fluxible quantum dots. The products are monodisperse and show low viscosity and excellent photoluminescence (see picture).

Auf den Punkt gebracht: Ein einfaches Extraktionsverfahren unter Verwendung von quartären Ammoniumsalzen mit einer Polyethylenglycol‐Kette als Phasentransferreagens bietet Zugang zu lösungsmittelfreien, fließfähigen Quantenpunkten. Die Produkte sind monodispers, wenig viskos und zeigen exzellente Photolumineszenzen (siehe Bild).

Two categories of nanoscale ionic materials (NIMs) based on multiwalled carbon nanotubes (MWCNTs) were obtained. According to the nature of organic modifier and the type of interaction, these NIMs can be divided into two categories referred to as A-MWCNTs-Fs and I-MWCNTs-Fs, respectively. These MWCNT derivatives were virtually solvent-free and showed good flowability even at room temperature. The liquidlike manner of these MWCNT derivatives was from their relatively high organic content and continual departing−recombining motion of the large organic ions as suggested by the comparison of rheological response of the two categories of MWCNT-based NIMs. Thermal property and temperature-dependent and strain-dependent viscoelasticity of MWCNT derivatives were related to the microscopic structure of their coating layer and subsequently related to the configuration, chemistry, and molecular dimension of modifying molecules to establish the property−structure relationship of MWCNT-based NIMs, which could guide our future work on NIMs to appropriate and promising applications based on their tunable and controllable physical properties.

A novel capacitor with high dielectric constant (ε) has been developed by blending poly(vinylidene fluoride) (PVDF) with polyamide (PA11). The blends show high dielectric constants (εblend= 40), which give better frequency stability (1 MHz), and excellent mechanical properties. Based on certain volume fractions, the measured dielectric constants (εblend) were found to exceed those of the corresponding polymers, in contrasted to conventional composites, where εpolymerA< εcomposite< εpolymerB. SEM investigations suggest that the enhanced dielectric behavior originates from significant interfacial polymer‐polymer interactions. DSC and XRD demonstrate that blending PA11 with PVDF affects the crystalline behavior of each component. However, the PA11/PVDF blends exhibit a slightly high dielectric loss (tanδ≈ 0.17), which is a great disadvantage to a capacitor. Adding a copolymer of styrene and maleic anhydride decreased the dielectric loss (tanδ≈ 0.057) and increased the dielectric constant (εblend= 60). Our findings suggest that the high‐εpolymeric blends created represent a novel type of material that is flexible and easy to process, of relatively high dielectric constant, of high breakdown strength and, moreover, is suited to applications in flexible electronics.

Ultrafine polyamide‐6 (UPA6) with a size of 4–8 μm was prepared via jet‐milling. Blends of poly (vinyl chloride) (PVC) and UPA6 using a reactive copolymer styrene–maleic anhydride (SMA‐18%) were prepared. The change in morphology and structure of the blends were studied using differential scanning calorimetry, scanning electron microscopy, and X‐ray diffraction. The blend behavior was also determined experimentally using dynamic mechanical analysis. Contrasted to the original PA6, the crystallinity of the UPA6 decreased, the size of its crystallites were reduced, and its melting point decreased to 175°C. In all blends, PVC formed the continuous matrix phase. SMA is miscible with PVC and tends to be dissolved in the PVC phase during the earlier stages of blending. The dissolved SMA has the opportunity to react with PA6 at the interface to form the desirable SMA‐g‐PA6 copolymer. This in situ formed SMA‐g‐PA6 graft copolymer tends to anchor along the interface to reduce the interfacial tension and results in finer phase domains. Cocrystallity existed in PVC/(UPA6/SMA) at a ratio of 82/(18/5). © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 850–854, 2005

The morphology and mechanical properties of PVC/SMA‐g‐PA6 blends were investigated in this paper. Graft to polymer SMA‐g‐PA6 was prepared via a solution graft reaction between SMA and PA6. FTIR test evidences the occurrence of the graft reaction between SMA and PA6. DSC analysis shows that SMA‐g‐PA6 has a lower melting point of 187°C, which may result in a decrease in crystallinity of PA6 and thus enable efficient blending of SMA‐g‐PA6 and PVC. Compatibilization was evidenced by the dramatic increase in mechanical properties, the smaller particle size and finer dispersion of PA6 in PVC matrix, and, further, a cocontinuous morphology at 16 wt % SMA‐g‐PA6 content. SMA‐g‐PA6 from the solution graft reaction can toughen and reinforce PVC material. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 432–439, 2004

This article describes the development of novel nanocrystalline poly(vinyl chloride) (PVC) for potential applications in PVC processes and reports improvements in the mechanical properties and thermal resistance. Before the preparation of nanocrystalline PVC via jet milling, PVC was spray-treated and heat-treated to improve its crystallinity. The pulverization and degradation, morphology, crystalline structure, and melting-point changes of postmodified PVC during jet milling and the relationship between the distributions of the particle size and processing temperature were investigated. X-ray analysis and density testing indicated increased density and improved crystallinity. The crystalline region of nanocrystalline PVC was less than 80 nm, with a particle size distribution of 5–20 μm and a melting point of less than 128°C. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 563–569, 2004

High-performance and environment-friendly biomass-based piezoelectric films have drawn much attention recently. Here, 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized cellulose nanofibril (TOCN)/molybdenum disulfide (MoS2) nanosheet bionanocomposite piezoelectric films were prepared through an environmentally benign pathway by aqueous dispersion. The TOCN/MoS2nanocomposite films exhibited good mechanical properties with the highest Young’s modulus of 8.2 GPa and tensile strength of 307 MPa. When the MoS2content was 4 wt%, the longitudinal piezoelectric constant (d33) of the composite film reached a maximum value of 31 pC/N, much higher than 12 pC/N of the neat TOCN film and other reported cellulose-based piezoelectric films. Moreover, nanogenerators fabricated from TOCN/MoS2composite films exhibited a maximum output voltage of 4.1 V and a short-circuit current of 0.21μA. Furthermore, the current generated by the nanogenerator was rectified and converted to direct current. A 10μF commercial capacitor was charged to 1.6 V at 120 s, indicating the ability to collect mechanical energy generated in the natural environment. Therefore, the TOCN/MoS2composite films are promising in the field of piezoelectric materials and nanogenerators.