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This work proposed a strategy to directly modify commercial sponges by synergistically reducing the viscosity of crude oil using solar-assisted chemical emulsifiers to achieve rapid adsorption and efficient recovery of crude oil.

An ideal oil/water separation membrane should possess the characteristics of high flux and separation efficiency, recyclability, as well as good mechanical stability. Herein, a facile method is applied to fabricate a Janus polylactic acid (PLA) fibrous membrane for efficiently separating surfactant-stabilized oil/water mixtures. The Janus PLA fibrous membrane architecture was prepared by electrospinning a PLA/carbon nanotubes (CNTs) fibrous membrane and the subsequent electrospinning of a PLA/SiO2 nanofluids (nfs) membrane onto one side of the PLA/CNTs fibrous membrane. Due to the strong electrostatic interaction between SiO2 nfs and CNTs, synchronous enhancement and plasticization of PLA fibrous membranes were achieved, which was far superior to that reported in the literature. The introduction of CNTs had caused an upshift of the hydrophobicity of the PLA/CNTs fibrous membrane (water contact angle (WCA) > 140°). In contrast, SiO2 nfs bearing long-chain organic anions and cations located onto the surface of the fibers during electrospinning to achieve superhydrophilicity (WCA ≈ 0°). Benefiting from completely opposite wettability on both sides of the Janus membrane, the obtained asymmetric Janus membranes exhibited a high flux (1142-1485 L m-2 L-1) and excellent oil/water separation efficiency (>99%), which were superior to those reported for other Janus membranes. Furthermore, the Janus membranes showed desirable flux recovery without any treatment (>80% for water-in-oil emulsions and >90% for oil-in-water emulsions, respectively, after 11 cycles), showcasing promising applications for water treatment in the future.

In this paper, the electronspun Polylactic acid (PLA)/TiO2 nanofluids (nfs) fibrous membrane with good toughness, hydrophilicity and antibacterial activities are fabricated by taking full advantages of solvent-free TiO2 nfs with amphiphilicity and ionic conductivity. The resulting PLA/TiO2 nfs fibrous membrane exhibits excellent mechanical performance with a tensile strength and elongation at break of 3.68 MPa and 97.32 MPa at 5 wt% loading, respectively, which is 4 and 8 times higher than that of pure PLA, respectively. Additionally, TiO2 nfs can migrate onto the surface of PLA fibers during electrospun process, which significantly enhanced hydrophilicity, antistatic property, moisture sorption capacity and wicking properties of PLA fabrics. Meanwhile, the membrane also showed ultrafast water filtration of 3500 L m−2 h−1 driven by gravity force, which is 10–12 times higher than that of commercial ultrafiltration membrane. After ion-exchange reaction with salt solution, excellent antibacterial activity (against E. coli and S. aureus was 95% and 99.9%, respectively) and separation efficiency (above 90% on E. coli) of the obtained fabrics are also achieved. Overall, organic nfs are an idea candidate for fabricating hydrophilic PLA based biodegradable fabric that can be applied in contaminated water treatment, antibacterial textiles and biodegradable absorption materials.

As a very promising biodegradable polymer, polylactic acid (PLA) has been applied in various fields. Unfortunately, the disadvantages of flammability and large amounts of molten droplets limit its application. In this work, we constructed a novel flame-retardant system by combining the as-prepared bio-based chitosan derivative (CS-TE) and aluminum hypophosphite (AP), and used it to improve the flame retardancy and anti-dripping property. When 3.75 wt% CS-TE and 11.25 wt% AP were incorporated into PLA, the PLA composite had a limiting oxygen index of 28.5 % and achieved a UL-94 V-0 rating as well as showed excellent anti-dripping behavior. Meanwhile, the peak heat release rate and total smoke production decreased by 52.3 % and 73.4 % respectively.

It is a challenge to fabricate a flexible and smart cotton fabric sensor with improved thermal conductivity while retaining electrical insulation. Herein, reactive multiwall carbon nanotube (MWCNT) nanofluid exhibiting soft glassy rheological behavior was successfully synthesized through simultaneous surface modification by (3-aminopropyl) triethoxysilane and dimethyloctadecyl[3-(trimethoxysilyl)propyl] ammonium chloride followed by ion-exchange reaction with nonylphenol polyoxyethylene ether sodium sulfate. Then, MWCNT nanofluid was used to coat MWCNT nanofluid/cotton fabrics by simple spraying. It was found that the addition of MWCNT nanofluid improved the thermal conductivity while preserving electrical insulation of the cotton fabric. The maximum thermal conductivity of MWCNT nanofluid/cotton fabric is 2.42 times that of cotton fabric. It was also observed that surface grafted non-conductive silane molecules and organic ion salt of MWCNT hinder the MWCNT inter-contacting with each other to form a conductive network for retaining electrical insulation. In addition, during the combustion process of cotton fabric, surface grafted organic molecules of MWCNT nanofluid began to decompose and thus promote the formation of the MWCNT conductive network, indicated by the presence of electric current. This could be valuable as a low-voltage DC power source for potential applications in fire alarm sensors.

The fluidity of solvent-free nanofluids is related to the structure between and within molecules consisting of graftable groups or groups that can be exchanged. Research into controlling the fluidi...

In this paper, a facile and environmentally friendly approach was used to prepare acrylate resin-based cotton fabric composites via adding reactive Mg (OH)2 fluids (MHFs) into trimethylolpropane triacrylate (TPT) monomer followed by coating on the cotton fabrics by photo-polymerization. The morphology, thermal stability, rheological behavior, and mechanical properties of polymer composites are systematically characterized by various technologies. Mechanical test results demonstrates that tensile strength and young’s modulus of the polymer composites are as high as 46 MPa and 1440.27 MPa, respectively, which is 3.5 and 9.1 times that of polymer composite in the absent of MHFs meanwhile without sacrificing the toughness. Moreover, it is amazingly found that the addition of MHFs can effectively reduce water vapor transmission rate of composite. Herein, these advantages of MHFs can be easily applied as encapsulation layer in the field of smart cotton fabric and electrical device.

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.

In this study, ferrous oxalate (FeC2O4) used as an effective heterogeneous Fenton catalyst, was inexpensively synthesized by a chemical precipitation method. The attractive efficiency was investigated to demonstrate the underlying mechanism of in-situ reactivation. Based on the mechanism, the important issue of effective performance suggested that the reactivation of active sites enhanced the activation of hydroxyl radical( OH) for degradation. In addition, the catalytic performance for industrial application was studied by evaluating the degradation of methylene blue (MB). In the typical process, a degradation efficiency over 94% was observed at 10 min, and it was improved to over 95% at 3 min under irradiation with a xenon lamp. The catalyst has high operational stability and reusability properties in the process. Remarkably, self-activation of the catalyst was observed during the recycling processes.

Developing a facile and energy-efficient separation membrane for the purification of highly emulsified oily wastewater is significant challenging due to the critical limitation of low flux, serious fouling, and a complex fabrication process. Therefore, we fabricated a superhydrophilic and underwater superoleophobic polyphenylene sulfide microfiber membrane, modified by chitosan, via a simple and facile strategy of dip-coating followed by hot pressing. The prepared membrane displays high superoleophobicity in strong acid, alkali, and salt solutions, with the oil contact angle of 150.08°, 150.46° and 151.89°, respectively. Additionally, the high porosity and diminutive pore size endow the membrane with superior performance for separating both surfactant-free and surface-stabilized oil-in-water emulsion. An ultrahigh permeation flux of up to 2250 L m−2 h−1 with a separation efficiency of > 99% is obtained driven solely by gravity. The flow rate and separation efficiency are higher than those of conventional separation membranes, demonstrating remarkable applicability for energy efficient separation. With the advantages of excellent antifouling performance and antibacterial activity, the as-prepared membrane exhibits robust reusability for long-term separation, which is promising for practical applications in the purification of oily wastewater.

It is challenging to fabricate a starch derivative with a plasticizing effect and good dispersion in a poly(lactic acid) matrix to achieve desirable performance. In this study, self-suspended starch fluids composed of modified granules as the core and polyethylene glycol-substituted tertiary amines as the shell were first fabricated via a combined carboxymethylation and acylation reaction. The as-prepared starch fluids exhibited liquid-like behavior and had semiconductor electric conductivity (4.91 × 10−5 S/cm) at room temperature without a solvent. The modulus of starch fluids was clearly reduced under the heating process and exhibited its initial flow properties upon cooling, displaying thermo-reversible behavior. The resultant fluids were then incorporated into a poly(lactic acid) matrix to produce fully biodegradable composites with desirable performance. At a loading level of 10 wt%, starch fluids exhibited simultaneous enhancements in elongation at break (increase of 164.7%) and thermal conductivity (increase of 119%) of PLA composites compared to pure PLA, attributable to the good dispersion and heat-transfer properties of starch fluids. In addition, PLA composites with 10 wt% loading of starch fluids demonstrated excellent antistatic performance (3.08 × 10−4 S/cm), suggesting that polar groups of the PLA structure and PEG groups of starch fluids contributed synergistically to the electrical conductivities of composites. These results indicate that starch fluids are promising antistatic agents and plasticizers for potential applications in biodegradable materials.

The phase behavior of biomolecules containing persistent molecular entities is generally limited due to their characteristic size that exceeds the intermolecular force field. Consequently, favorable properties normally associated with the liquid phase of a substance, such as fluidity or processability, are not relevant for the processing of biomolecules, thus hindering the optimal processing of biomolecules. The implied problem that arises is how to convert folded biomolecules to display a richer phase behavior. To alleviate this dilemma, a generic approach to liquefied polysaccharides-based polymers is proposed, resulting in a polysaccharide fluid with a tunable condensed state structure (solid-gel-liquid). Polysaccharide biobased fluids materials transcend the limits of the physical state of the biobased material itself and can even create completely new properties (different processing methods as well as functions) in a variety of polymeric structures. Considering the solvent incompatible high and low-temperature applications, this method will have a great influence on the design of nanostructures of biomolecular derivatives and is expected to transform biomass materials such as polysaccharide biopolymers from traditional use to resource use, ultimately leading to the efficient use of biomass materials and their sustainability.

In view of the sustainable and environmentally friendly characteristics of solar energy, solar water evaporation has been identified as a promising approach to mitigate the global water crises. However, it is still a great challenge to develop a portable, flexible, scalable, and high-performance solar water evaporation material. Herein, a bilayer-structured solar water evaporation material consisting of a top multiwalled carbon nanotube (MWCNT) layer and a bottom polyphenylene sulfide/fibrillated cellulose (PPS/FC) paper was fabricated via a simple vacuum filtration technology for efficient solar water evaporation. The MWCNT layer performs as a light absorber with a high solar absorptance (∼93%) in the wavelength range from 400 to 1200 nm and good light-to-heat conversion capability, while the bottom layer (porous network-structured PPS/FC paper) exhibits excellent water transporting ability, high temperature stability, and good thermal insulating capability (0.0467 W m-1 K-1). Benefiting from the above advantages, an attractive water evaporation rate of 1.34 kg m-2 h-1 was achieved with near ∼95% efficiency under 1 sun irradiation (1 kW m-2). Moreover, the MWCNTs@PPS/FC paper maintains high solar evaporation efficiency after several cycles, indicating long-term durability and good reusability. Moreover, the collected clean water using the MWCNTs@PPS/FC paper from seawater of different salinities, simulated wastewater samples with different pH values or containing heavy metal ions, as well as industrial dyes, satisfy the drinkable water standard (defined by WHO), demonstrating excellent seawater desalination and wastewater purification capability. The advanced performances of the MWCNTs@PPS/FC paper could inspire novel paradigms of solar-driven water evaporation technologies in drinkable water collection.

In this paper, solvent-free microcrystalline cellulose fluids (MCCFs) with liquid-like behavior were synthesized for the first time through surface grafted polyethylene glycol-substituted tertiary amines into microcrystalline cellulose (MCC) followed by fabricating MCCFs based polylactic acid (PLA) fabric (PLA/MCCFs) via electrospinning method. Owing to low viscosity of MCCFs at room temperature, the addition of MCCFs not only hardly affected the viscosity of electrospinning solution, but also improved the thermal stability of as-prepared PLA fibers. Interestingly, it was amazingly found that surface micropore morphology of PLA fabric diminished, and even disappeared with the content of MCCFs increasing during solvent evaporation process, which may be ascribed to the rapid migration of MCCFs into micropore before solidification. More importantly, the tensile strengths of PLA/MCCFs fabric with 10 wt% content of MCCFs achieved as high as 13.68 MPa, which was 3.18 times as much as that of 4.3 MPa for pure PLA fabric meanwhile the elongation at break of PLA/MCCFs fabrics increased from 13.19% for pure PLA fabric to 48.84% for PLA/MCCFs fabric with 15 wt% content of MCCFs. Beyond above mentioned, the water contact angle for pure PLA fabric was 127° (hydrophobicity), whereas other samples were close to 0° with addition of MCCFs, displaying the super-hydrophilicity. It was possibly inferred that MCCFs quickly migrated towards to the surface of fibers rather than staying inside of the fibers during the electrospinning process, leading to positive effect on the hydrophilicity of the PLA fibers. Finally, it is anticipated that this strategy for fabricating PLA fiber using this novel MCCFs as filler will pave the way for developing high performance PLA composites with desirable properties in the future.

Superhydrophobic material involves the fabrication of appropriate roughness and low surface energy. Studies concerning enhancing the attachment between substrates and low surface energy material have been reported. Hence, it might also be feasible to make low surface energy material as an interface binder to enhance the attachment. In our work, the simple dip-coating method was used to fabricate polybenzoxazine (PBZ)/SiO2-coating cotton (PBZSC) fabric for rapid oil–water separation. The surface morphology and wettability of the PBZSC fabric as well as the properties of the separation were explored using various methods. These results demonstrated that PBZSC fabric not only had excellent thermal properties, but also maintained excellent superhydrophobicity (WCA > 150°) under various harsh conditions which was mainly attributed to higher surface roughness contributed by SiO2 and lower surface energy, heat resistance as well as acid and alkali resistance from PBZ resin, respectively. More importantly, the separation conducted by the PBZSC fabric not only showed great recycle property, but also separated a series of oil and water mixtures with up to 96% separation efficiency. Therefore, it is anticipated that this low-cost PBZSC fabric will be readily and widely utilized in designing multifunctional membrane for large-area oil-spill cleanup without using fluoropolymers or silicones.

A systematic study has been carried out to develop a material with significant protection properties from galactic cosmic radiation and solar energetic particles. The research focused on the development of hydrogen-rich benzoxazines, which are particularly effective for shielding against such radiation. Newly developed benzoxazine resin can be polymerized at 120 °C, which meets the low-temperature processing requirements for use with ultrahigh molecular weight polyethylene (UHMWPE) fiber, a hydrogen-rich composite reinforcement. This highly reactive benzoxazine resin also exhibits low viscosity and good shelf-life. The structure of the benzoxazine monomer is confirmed by proton nuclear magnetic resonance and Fourier transform infrared spectroscopy. Polymerization behavior and thermal properties are evaluated by differential scanning calorimetry and thermogravimetric analysis. Dynamic mechanical analysis is used to study chemorheological properties of the benzoxazine monomer, rheological properties of the cross-linked polybenzoxazine, and rheological properties of UHMWPE-reinforced polybenzoxazine composites. The theoretical radiation shielding capability of the composite is also evaluated using computer-based simulations. Fil: Iguchi, Daniela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnología en Polímeros y Nanotecnología. Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnología en Polímeros y Nanotecnología; Argentina. Case Western Reserve University; Estados Unidos Fil: Ohashi, Seishi. Case Western Reserve University; Estados Unidos Fil: Abarro, Ghizelle J. E.. University of the Philippines Diliman; Filipinas. Case Western Reserve University; Estados Unidos Fil: Yin, Xianse. Case Western Reserve University; Estados Unidos. Wuhan Textile University; República de China Fil: Winroth, Scott. Material Answers LLC; Estados Unidos Fil: Scott, Chris. Material Answers LLC; Estados Unidos Fil: Gleydura, Molly. Case Western Reserve University; Estados Unidos. Hathaway Brown School; Estados Unidos Fil: Jin, Lin. Case Western Reserve University; Estados Unidos Fil: Kanagasegar, Nithya. Case Western Reserve University; Estados Unidos Fil: Lo, Cherie. Case Western Reserve University; Estados Unidos Fil: Arza, Carlos R.. Case Western Reserve University; Estados Unidos Fil: Froimowicz, Pablo. Case Western Reserve University; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnología en Polímeros y Nanotecnología. Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnología en Polímeros y Nanotecnología; Argentina Fil: Ishida, Hatsuo. Case Western Reserve University; Estados Unidos

Ag3PO4 and chitosan fiber (CF) composites were successfully fabricated using an in situ growth technique. The structure and properties of the obtained Ag3PO4/CF composites were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy (SEM), energy dispersive spectroscopy, and UV–visible diffuse reflectance spectroscopy. SEM results suggested that the 50–500 nm Ag3PO4 particles grew on the CF surface into a spherical or dentate shape. Photocatalytic degradation of methyl orange (MO) solution was used as a typical reaction to evaluate the visible-light photocatalytic performance of the Ag3PO4/CF composites. The reaction results indicated that the Ag3PO4/CF composites-3 exhibited excellent photodegradation efficiency, with 93.8% removal of the MO solution. The effects of MO concentrations and cycling runs on the photocatalytic performance of the Ag3PO4/CF composites were evaluated as well.

To dispose the increasing oil pollution, tremendous effective ways have been proposed to deal with the oil/water mixture. In this study, polyphenylene sulfide (PPS) microfiber membrane was firstly employed as the substrate for separation. Polyethylene wax (PEW) powder and polytetrafluoroethylene (PTFE) ultrafine powder were simply and effectively introduced on the PPS membrane by employing one-step spray-coating method. The as-prepared membrane displayed excellent oil affinity and water-repellent behaviors. Significantly, the obtained membrane showed long-term stability under various extreme conditions such as strong acid, alkali, salt solutions and high temperature. Moreover, this membrane could maintain high oil flux (above 3500 L/m2 h) and separation efficiency (above 98%) even after 20 cycles of oil/water separation and isolate a wide range of oil/water mixture effectively. The fabrication of superhydrophobic and superoleophilic PPS microfiber membrane presented here can be easily scaled up on a large scale, which will provide attractive potential in practical oil/water separation.

UV-blocking, superhydrophobic and robust cotton fabrics were successfully developed by combination of polyvinylsilsesquioxane (PVS) and nano-TiO2 for the first time. The influence of the add-on amount on morphologies, ultraviolet (UV) protection, hydrophobicity, mechanical properties, rigidity and thermal degradation of the treated cotton fabrics was studied. The nano-TiO2 particles were found to be embedded in the PVS film layer on the surface of cotton fibers by covalent Ti–O–Si bonds after curing. The UV blocking and hydrophobic properties of the functionalized cotton fabrics were also improved with increases in the amount of add-on, compared to the reference materials. The improvements on the UV blocking, water repellency and rigidity of the treated cotton fabrics are likely attributed to synergism between the PVS polymer and nano-TiO2. The mechanical properties of the finished cotton fabrics are significantly enhanced by treatment of composite coatings. However, the resistance to thermal degradation evidently did not change despite changes in the add-on amount. Hence this strategy for developing the composite coatings can guide in constructing the advanced functional surface, and the discovery of this new class of UV-blocking, superhydrophobic and robust cotton fabrics has many potential applications such as advanced UV-blocking textiles, stretchable electronic devices and self-cleaning fields.

In this study, a new alternative nonwoven based on engineering plastic polyphenylene sulfide (PPS) was explored as the support to construct high performance and safety separator for the first time. By the method of physical coating polymer poly(vinylidene fluoride-hexafluoropropylene) (PVDF-HFP) and inorganic nanoparticle SiO2 on the support, the designed composite separator was successfully obtained for lithium ion battery. Systematic investigations ranging from physical properties, thermal properties to electrochemical performances were carried out. It was found that compared with commercialized polyolefin separator, PPS nonwoven-based composite separator possessed higher porosity, air permeability, improved electrolyte wettability and electrolyte uptake, thus being helpful for lithium ion transfer between electrodes and increasing the ionic conductivity. These behaviors accordingly endowed battery with superior discharge capacity at various discharge current rates from 0.2 C to 2 C. Moreover, the composite separator was observed to exhibit excellent dimensional stability even after thermal treatment at 250 °C and present good flame retardant ability. The afore-mentioned outstanding performances of PPS nonwoven-based composite separator would shed light on the development of high power lithium ion battery.

From the industrial viewpoint, it would be desirable to use neutral aqueous solution when applying chitosan coatings for textile treatment. However, in most cases, chitosan only dissolves in acid solvents. In this work, a self-suspended chitosan derivative with liquid-like behavior was prepared by decorating chitosan with a quaternary ammonium salt followed by ion exchange with nonylphenol polyoxyethylene ether sodium sulfate (NPES). The chitosan derivative with higher NPES content dissolved in neutral aqueous solution, and even exhibited liquid-like viscous behavior without water at room temperature. The morphology, structure, composition, and rheological behavior of the chitosan derivative were systematically characterized using various methods. It was found that incorporation of NPES into the chitosan structure could greatly enhance its dispersion, while the modulus and viscosity of the derivative gradually decreased with increasing temperature. Moreover, the novel chitosan derivative not only directly coated cotton fabric via hydrogen-bonding interaction without removing water but also improved the long-term wettability and moisture retention because of the dual-layer ion structure of the chitosan derivative. The results showed that cotton fabrics coated with such chitosan derivatives could be developed as wound dressing materials in future work.

It is always a challenge to prepare multifunctional epoxy resins (EP) composites with excellent flame retardance, mechanical property and high transparency. In this work, a reactive flame-retardant (BDO) was synthesized from DOPO, 3,5-diamino-triazolz and thiophene-2-formaldehyde, and taken to prepare EP/BDO composites. Surprisingly, benefitting from the synergy of efficient flame retardant unit (DOPO structure), catalytic curing unit (triazole structure) and optical functional structure (thiophene-2-formaldehyde), the EP composites with excellent comprehensive performance was obtained. In detailed, after adding only 5 wt% BDO, the EP composites passed the UL-94 V-0 level, and the limiting oxygen index was increased to 33% from 22.5% of neat EP. At the same time, EP/BDO-5 showed obvious heat suppression and smoke suppression effects. Besides, EP/BDO-5 presented excellent mechanical strength, that the tensile strength and bending strength were increased by 25% and 30% compared with neat EP. Moreover, EP/BDO composites maintained the same good light transmittance as neat EP, and also presented enhanced Tg and dielectric property. In addition, the dual phase flame-retardant mechanism was revealed through systematically analyzing residues after combustion and the gaseous phase products of flame retardant. The above results indicated EP/BDO composites with excellent comprehensive performance possessed a great potential application in high-performance composites fields.

This paper develops a novel approach to prepare solvent-free cerium dioxide (CeO2) nanofluids through N,N-didecyl-N-methyl-N-(3-trimethoxysilylpropyl) ammonium chloride covalently grafted o...

Functionalized magnesium hydroxide fluids (MHFs) with both grafting reactive acrylate groups and organic long chain ion are successfully fabricated and then incorporated in poly(ethylene glycol) diacrylate (PEGDA) to produce flexible MHFs/PPEGDA coated hybrid cotton fabric via UV photo-polymerization. The morphology, composition, transparency, rheological behavior, mechanical and flame retardant properties of MHFs/PPEGDA coating are systematically characterized by various techniques. It is found that tensile strength and young’s modulus of MHFs/PPEGDA/cotton composite are as high as 46 and 556 MPa at MHFs loading amount of 40 wt%, respectively, an enhancement of 58.6 and 66.4% in comparison with PPEGDA/cotton composite. What’s more, the addition of MHFs not only reduces the surface energy of PEGDA to improve its film-forming property during polymerization process, but also maintains high transparency over 90%. Besides the above mentioned advantages, MHFs/PPEGDA coating as thermal induced shape memory material could be fixed their shape at − 4 °C and rapidly recover their original shape at 60 °C, which is related to the melting transition temperature of MHFs. More importantly, with the synergistic effect of magnesium hydroxide and surface grafted organic long chain ion molecules, the flame retardant property of MHFs/PPEGDA/cotton is also significantly improved. These functionalized organic/inorganic fluids provide a simple approach to fabricate high performance cellulose fabrics with tunable properties in the textile industry.

The simultaneous achievement of ultrafast water vapor transport and evaporation, robust mechanical properties, rapid heat dissipation, and excellent antibacterial activity is still highly challenging for advanced bio-based degradable textile composites. Herein, multifunctional biodegradable composite fibers were designed via converting the cellulose powder into solvent-free spherical cellulose crystal fluids (CNCfs) followed by embedding into bio-based polylactic acid (PLA) fibrous membrane using the electrospinning. By taking full advantage of the low viscosity, amphiphilicity and high dispersion of CNCfs, the as-prepared bio-based fibrous membranes with tunable surface chemical and excellent mechanical properties (simultaneous plasticizing and reinforcement) were obtained. Due to the unique bilayer ion structure of the CNCfs located on the surface of PLA fiber after the electrospinning process, the fibrous membrane shows prominent superhydrophilicity (water contact angle of 0°) along with enhanced absorption water capacity and water vapor transmission rate (WVTR) of 3.612 kg m−2 h−1 (81 times higher than the pure PLA fibrous membrane). Moreover, the hygroscopicity-inspired design also endows PLA/CNCfs fibrous membrane with antistatic performance, rapid heat dissipation (decreased by 2 °C relative to the PLA bulk) with high thermal conductivity of 0.27 W/mK and excellent antibacterial activity of 98.5% and 92.7% against E. coli and S. aureus, respectively. Overall, this facile and effective strategy provides a promising route for the fabrication of multifunctional biodegradable fibrous membranes for use in environmental-friendly medical textiles, personal protection and human health applications.

A convenient and green approach was utilized to prepare the suspended carbon black fluids (SCBF) using carboxylic CB nanoparticles with diameters of 15nm as the core and poly(ethylene oxide)-block-poly(propylene oxide)-block-poly(ethylene oxide) (PEO-b-PPO-b-PEO) as surface modifier via hydrogen bonding interaction. It was found that when the total polymer content (strongly adsorbed layer and weakly adsorbed or free layer) was greater than 60wt%, the SCBF exhibited liquid-like behavior without solvent. More interestingly, the flow mechanism mainly related to surface polymer content, which greatly differed from ionically or covalently nanofluids systems. Besides, the thermal, dispersibility, electrical conductivity properties and rheological behaviors, as well as microstructure of SCBF were systematically investigated using various methods. Moreover, the SCBF as fillers were used to prepare SCBF/Poly(vinyl alcohol) (PVA) composites for producing the simultaneous reinforcement and plasticization effect due to the unique fluidity of SCBF and interfacial interactions between the PVA molecules and SCBF via hydrogen bondings. Keywords: Nanofluids, Reinforcement, hydrogen bonds, Nanocomposites

Nanofibers based on natural polymers have recently been attracting research interest as promising materials for use as skin substitutes. Here, we prepared photocrosslinked nanofibrous scaffolds based on methacrylated chitosan (MACS) by photocrosslinking electrospun methacrylated chitosan/poly (vinyl alcohol) (PVA) mats and subsequently removing PVA from the nanofibers. We comprehensively investigated the solution properties of MACS/PVA precursors, the intermolecular action between MACS and PVA components, and the morphology of MACS/PVA nanofibers. Results indicated that the fiber diameter and morphology of the photocrosslinked methacrylated chitosan-based nanofibrous scaffolds were controlled by the MACS/PVA mass ratio and showed highly micro-porous structures with many fibrils. In vitro cytotoxicity evaluation and cell culture experiments confirmed that MACS-based mats with micro-pore structure were biocompatible with L929 cells and facilitated cellular migration into the 3D matrix, demonstrating their potential application as skin replacements for wound repair.

To improve water stability of hydrophilic nanofibers, photocrosslinked maleilated chitosan/methacrylated poly (vinyl alcohol) (MCS/MPVA) bicomponent nanofibrous scaffolds were successfully obtained by electrospinning of aqueous MCS/MPVA solution and consequent photopolymerization. The parameters of MCS/MPVA solutions such as viscosity and conductivity were measured to evaluate electrospinnability of the blend solutions. The bicomponent nanofibrous scaffolds were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) analysis and differential scanning calorimetry (DSC), respectively. SEM results indicated that MCS/MPVA weight ratios significantly influenced the morphology and diameter distribution of the nanofibers. XRD and DSC investigated that there was strong interaction caused by hydrogen bonding between molecular chain of MCS and MPVA. Water stability test confirmed that the photocrosslinked matrix with a MCS/MPVA ratio of 10/90 retained excellent integrity of the fibrous structure in water. The in vitro cytotoxicity evaluation revealed that photocrosslinked nanofibrous scaffolds entailed good cellular compatibility, and could be used as potential wound dressing.

Self-reinforcement gel-like halloysite nanotube (g-HNT) hybrids with various viscoelastic behaviors were fabricated by firstly treating with various concentrations of sodium hydroxide (NaOH) solution and then grafting tertiary amine and ion-exchange reacting with sulfonate anions. The morphology, composition, thermal stability and rheological behavior of the g-HNT hybrids were systematically characterized and analyzed using various methods. It is found that the viscoelasticity of g-HNT hybrids can be easily regulated by using different NaOH solution-treated HNTs as inorganic core and temperatures. In addition, the g-HNT hybrids treated with medium concentration of NaOH (0.06 mol L−1) have the lowest viscosity and highest level of dispersion compared with those treated with other concentrations of NaOH solution. Due to the amphiphilic nature of g-HNT hybrids and their lower viscosity than HNT powder, as novel hybrid fillers, they were utilized to prepare polystyrene composites by direct melt blending for achieving simultaneous reinforcement and plasticization effects. Besides the above mentioned advantages, the thermal conductivity of polystyrene composites is also surprisingly improved by reducing the interfacial mismatch between the filler and polymer matrix. The solvent-free and self-reinforcement hybrids provide a convenient and green path for fabricating high-performance polymer composites. © 2017 Society of Chemical Industry

A novel flame retardant POBDBI was generated by the reaction of p-dibenzaldehyde, 5-amino-2-benzimidazolinone and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO), and employed to epoxy resin. The structure of POBDBI was measured by FT-IR and NMR tests. Then flame-retardant EP was fabricated by using POBDBI as a flame-retardant. The thermal stability, flame-retardant performance and fire behavior were investigated by a serious of comprehensive instruments. Combustion tests show the flame-retardant performance of composite materials has been significantly improved. For example, the EP/POBDBI-1.0 with the phosphorus content of 1.0% accorded a V-0 rating and its limiting oxygen index (LOI) value increased to 36.5%. Besides, total smoke production (TSP), peak heat release rate (PHRR) and total heat release (THR) of EP/POBDBI-1.0 dropped significantly, and the corresponding values were decreased by 48.4%, 48.9% and 8.7%, respectively. At the same time, the composition, morphology of chars and gaseous products of POBDBI were studied by X-ray photoelectron spectroscopy (XPS), FT-IR, scanning electron microscope (SEM) and Py-GC/MS. These results presented that POBDBI could not only exerted free radical capture effect, but also enhanced the density of char residue.

In this work, a fully biodegradable poly(butylene succinate) (PBS) biocomposite was fabricated from ultrafine PBS fiber and waste paper (WP) using a paper-manufacturing and compression molding method. A PBS biocomposite containing 60 wt% WP showed a tensile strength, elongation at break, flexural strength, flexural modulus, interlaminar shear strength (ILSS), and impact strength of 78.1 MPa, 11.1%, 92.0 MPa, 7.5 GPa, 2.9 MPa, and 36.9 kJ/m2, respectively, which were superior to those of previously-reported PBS biocomposites. The damage mechanics reveals that tremendous deformation of plant fibers (PF) from WP and their riveting improved the mechanical properties of WP/PBS biocomposites. The weight loss ratio of WP/PBS-60 wt% biocomposite during biodegradation reached 95.1 wt% after immersion in an enzyme solution for 35 d. This fabrication approach provides a novel and facile strategy to develop high-performance, low-cost, and fully biodegradable PBS biocomposites.

Functionalized liquid-like graphene@SiO 2 hybrids are fabricated by using the graphene@SiO 2 as core and nonionic copolymer as shell in aqueous solution at room temperature. The hybrid materials can flow above 45 °C and have a particular thermal invertibility. The morphology, chemical composition, dispersibility and stability, as well as rheological behavior are systematically characterized by various methods. It is shown that well-dispersed SiO 2 nanoparticles are tightly anchored on the surface of graphene sheet via hydrogen bonding interaction under the synergetic effect of 3-(trimethoxysilyl)-1-propanethiol and copolymer to prevent the aggregation of graphene sheet. What is more, the hybrid materials keep remarkably stability and dispersibility in organic solvents and aqueous solution. More importantly, rheological tests indicate that viscoelastic behavior of graphene@SiO 2 hybrids is effectively regulated through varying the amount of surface nonionic copolymer and silane coupling agent, respectively. In addition, the liquid-like graphene@SiO 2 hybrids as a novel of hybrid coating make the substrates transfer from hydrophobicity to hydrophilicity. More interestingly, the damaged coating can be self-healed under immersing water or heating conditions, respectively. This simple and environment friendly approach will benefit for fabricating large scale graphene based hybrid materials in application of functional coating and rheological additives.

This paper first develops a novel approach to prepare solvent-free nanonickel (Ni) nanofluids via hydrogen bonding between poly(ethylene oxide)-block-poly(propylene oxide)-block-poly(ethylene oxide) and 3-(Trimethoxysilyl)-1-propanethiol-modified Ni powder with average diameter of 80 nm to solve the problem of nanoparticles agglomerating due to the anisotropic dipolar attraction. It is interestingly found that Ni nanofluid is solid at room temperature while it undergoes solid–liquid transition without solvent at 50.7°C. The content of Ni is up to 12.1 wt%. The average diameter of core-shell structure of Ni nanofluids is 182 nm without agglomerations. It is worth noting that incorporation of Ni powder can elevate remarkably initial decomposition temperature of block copolymer due to high dispersity of Ni powder after modification. In addition, the viscosity of Ni nanofluids is found to be less than 10 Pa · s at 100°C, which is between that of water and honey, 0.001 and 10 Pa · s, respectively, at 2...

A series of solvent-free ionic silica (SiO2) nanofluids of 12.3–17.3 nm in diameter were synthesized by surface functionalizing nanoscale SiO2 with a charged corona and ionically tethering with oligomeric chains as canopy. The structure and properties of the nanofluids were systematically characterized by Fourier transform infrared (FTIR), differential scanning calorimeter (DSC), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and rheology tests. The resultant nanofluids with low-molecular-weight oligomeric as canopy are homogeneous, stable yellow-like fluids with no evidence of phase separation at room temperature, while other nanofluids containing high-molecular-weight as canopy behave like a soft glassy, and they exhibit fluidity with still high modulus and viscosity above 60°C. For deeper understanding of the nature of SiO2 nanofluids, the rheological behavior, thermal stability, as well as morphology of SiO2 nanofluids were investigated in details. The flow propertie...