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In this work, a poly(ethylene glycol)-b-poly(1H,1H,7H-dodecafluoroheptyl methacrylate) (PEG- b -PDFMA) block copolymer was first synthesized by the reversible addition−fragmentation chain transfer (RAFT) polymerization. Then a novel facile approach was developed to fabricate oval cuboid TiO 2 particles with mesoporous structure by using the PEG- b -PDFMA block copolymer as a template and titanium tetrabutoxide (TBOT) as a precursor, followed by evaporation-induced self-assembly (EISA) process and calcination process. The results show that the PEG- b -PDFMA block copolymer can control the oriented assembly of nanoparticles and act as templates for the formation of a mesopore. It is found that the mass ratio of TBOT/PEG- b -PDFMA and water content in the solution have a significant influence on the morphology of TiO 2 particles. When the mass ratio of TBOT/PEG- b -PDFMA is 0.25/1, oval cuboid TiO 2 particles with mesopores are obtained, which exhibits a high photocatalytic activity for the degradation of methylene blue (MB) dye under UV light irradiation. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract The diverse morphologies of aggregates formed by the self-assembly of block copolymers in selective solvents have attracted widespread attention, but the design of aggregate shapes is still limited owing to the thermodynamic favorability of sphere formation. In this paper, we report our discovery that polyhedral aggregates can be formed by the self-assembly of 1H,1H,2H,2H -perfluoro- 1 -dodecanol (PFD)-grafted amphiphilic polystyrene- b -poly(acrylic acid) (PS- b -PAA- g -PFD) copolymers in water at room temperature. It is determined that the crystallization of fluorocarbon side chains at the surface of PS- b -PAA- g -PFD aggregates induces the formation of a polyhedral shape. The morphology of aggregates can be controlled by the dialysis temperature, the grafting ratio of PFD in PS- b -PAA- g -PFD copolymers, and the initial copolymer concentration. The layers of polyhedral aggregates show excellent antibacterial adhesion properties. We anticipate that this method will expand the promise of self-assembly for the synthesis of a series of nonspherical micellar nanoparticles, which have promising applications in various fields. [ABSTRACT FROM AUTHOR]

In this paper, mesoporous Cu 2 O–CeO 2 nanospheres were fabricated via a facile, low-temperature solution route in the presence of poly(2-vinylpyridine)- b -poly(ethylene Oxide) (P2VP- b -PEO) block copolymers. The prepared mesoporous Cu 2 O–CeO 2 nanospheres were characterized systematically by scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) and nitrogen adsorption/desorption. The formation mechanism of mesoporous Cu 2 O–CeO 2 nanospheres was discussed. The results show that the molar ratios of Ce 3+ /Cu 2+ and the reaction time have an important influence on the nanostructure of Cu 2 O–CeO 2 composite spheres. The resultant Cu 2 O–CeO 2 nanospheres exhibit superior catalytic activities in the reduction of 4-nitrophenol to 4-aminophenol by NaBH 4 . The activity factor (K =  k /m) for the Cu 2 O–CeO 2 nanospheres prepared with the molar ratio of Ce 3+ /Cu 2+ of 5/1 is 3006.6 s −1  g −1 , which is much higher than reported values. This paper demonstrates a highly controllable approach to the production of mesoporous Cu 2 O–CeO 2 nanospheres, which have potential applications in the areas of catalysis, adsorption, sensors and so on. [ABSTRACT FROM AUTHOR]

Different structures of Cu2O nanoparticles (NPs) were synthesized by using poly(2-vinylpyridine) -b-poly(ethylene oxide) (P2VP-b-PEO) block copolymers as capping agent. The method involve the complextion of P2VP-b-PEO with Cu(NO3)2and then reduction of Cu2+to Cu2O by hydrazine hydrate. By adjusting the molar ratio of hydrazine hydrate to Cu2+(MR), hollow spheres, solid spheres, cubes and octahedron can be fabricated. However, when Au NPs are used as seeds for Cu2O formation, Au-Cu2O core-shell NPs were obtained and the MR have little effect on the morphology of Cu2O nanostructures. The prepared Cu2O NPs with different structures may find applications in solar energy photovoltaics and photocatalysis. [ABSTRACT FROM PUBLISHER]

Composite containing a TiO2and hollow Au−Ag nanoparticles (H−AuAg−NPs) have been prepared by using H−AuAg−NPs with block copolymer shells as templates, and the influence of annealing temperature on structure, surface property, and the photocatalytic activity has been investigated. The structures of H−AuAg−NPs/TiO2Composites were examined by X-ray diffractometer (XRD) and transmission electron microscopy (TEM). The carbon content was measured by thermogravimetric analyses (TGA). The specific surface areas and pore volumes of the H−AuAg−NPs/TiO2composites after annealing at different temperature were characterized using the nitrogen gas sorption technique. The photocatalytic activities of the H−AuAg−NPs/TiO2composite were investigated by the photodecomposition of methylene blue (MB). The results show that the TiO2in H−AuAg−NPs/TiO2composite is amorphous upon annealing at 400°C. Anatase phase appears as annealing temperature is increased to 450°C, and the crystallinity is further increased if the annealing temperature is raised to 500°C. The specific surface area decreases with annealing temperature from 400°C to 500°C. It is found that the H−AuAg−NPs/TiO2composite annealed at 450°C shows the highest photocatalytic activity. [ABSTRACT FROM PUBLISHER]

ABSTRACT 4-Hydroxythiophenol (HTP) grafted poly(styrene- b-acrylic acid) (PS- b-PAA) block copolymers (BCPs) (PS- b-PAA- g-HTP) was synthesized using the esterification reaction between the carboxyl groups and hydroxyl groups. Self-assembly behavior of the graft copolymer in 1,4-dioxane/water was investigated. Assemblies of different morphologies, porous, and bowl-shaped structures, could be easily prepared. A possible mechanism for the formation of the porous and bowl-shaped structures was discussed. The present study showed a facile method for the preparation of functionalized PS- b-PAA BCPs, which could easily self-assembly into novel structures in aqueous solution. These assemblies may be used to generate new functional materials. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016, 54, 1551-1557 [ABSTRACT FROM AUTHOR]

The multifunction antibacterial hemostatic materials can reduce blood loss, infection and wound complications, which probably decrease morbidity and health care costs. However, the contradictory relationship between antibacterial ability and biocompatibility, and the unnecessary blood loss restricts the practical application of hydrophilic cationic antibacterial hemostatic materials. Herein, a multifunctional temperature-triggered antibacterial hemostatic fluorocopolymer aggregate coating was developed. After self-assembly and quaternization process, the quaternized poly(N,N-dimethylaminoethylmethacrylate)- b -poly(1H,1H,2H,2H -heptadecafluorodecyl acrylate) block copolymers (PDMA- b -PFOEMA) aggregate coating consisting of fluoropolymer and quaternary ammonium salt were built. The synergistic effect on fluorinated block with low surface energy and quaternary ammonium salt block with bactericide activity severs the way of initial bacterial attachment and proliferation, while the migration of fluorinated block greatly promotes the biocompatibility and anti-adhesion performance in response to the switch from room temperature to physiological temperature. Furthermore, the fluorocopolymer aggregate coating with hydrophobic properties possessed the property of rapid coagulation, low blood loss, minor secondary bleeding and least bacteria infiltration. The multifunctional temperature-triggered fluorocopolymer aggregate coating with antifouling, antibacterial and hemostatic properties may have a great potential in the biomedical application. [Display omitted] • Self-assembly process changes temperature-responsive behaviors of the coating. • The apparent contradiction between bactericidal ability and biological toxicity was relieve by the coating. • The coating prevents excessive blood loss before hemostasis through hydrophobic fluoropolymer. [ABSTRACT FROM AUTHOR]

Highly ordered mesoporous titania with a hexagonal mesostructure has successfully been synthesized. • Highly ordered mesoporous titania with a hexagonal mesostructure has successfully been synthesized. • The synergistic interactions among titanium precursor, block copolymer templates and solvent play a vital role in the formation of highly ordered structures. • The Highly ordered mesoporous titania showed superior photocatalytic activity under visible light irradiation. Mesoporous titania has gained increasing interest because of its outstanding properties and promising applications in a wide range of fields. Herein, highly ordered mesoporous titania with a hexagonal mesostructure has successfully been synthesized via the solvent evaporation induced micelle fusion–aggregation assembly method by using polystyrene- b -poly(2-vinyl pyridine) (PS- b -P2VP) diblock copolymer as a template, titanium citrate (TIC) as a precursor and a mixture of pyridine and ethanol as the solvent. It is worth noting that addition of pyridine to the system can generate the synergistic interactions among titanium precursor, block copolymer templates and solvent and give the PS- b -P2VP/TIC composite micelles enough time to assemble into the ordered structures during the evaporation-induced self-assembly (EISA) process. The prepared highly ordered mesoporous TiO 2 samples were characterized by transmission electron microscopy (TEM), scanning electron microscope (SEM), small angle X-ray scattering (SAXS), UV–vis diffuse reflectance spectrophotometry and N 2 adsorption analysis etc. By using the highly ordered mesoporous titania as photocatalysts in degradation of methylene blue (MB) under visible light irradiation, a high photocatalytic performance can be achieved and enhanced via further doping, which show that the highly ordered mesoporous titania have a potential application in wastewater treatment. [ABSTRACT FROM AUTHOR]

A simple approach towards the fabrication of Au-CeO 2 Janus-like nanoparticles is presented. Composite micelles of polystyrene- block -poly (ethylene oxide) (PS- b -PEO)/Ce(NO 3 ) 3 /HAuCl 4 with HAuCl 4 and Ce(NO 3 ) 3 precursors incorporated in the PEO domains are prepared first. By manipulating the pH value of the composite micelles solution, a redox reaction between Au(III) with Ce(III) in the PEO domains occurs and Au-CeO 2 Janus-like nanoparticles composed of a porous CeO 2 and an Au nanoparticle are generated. X-ray diffraction (XRD), UV–vis spectrum (UV), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) measurements are employed to characterize the Janus-like nanoparticles. The catalytic degradation of methyl orange dye (MO) under ultrasonic irradiation is chosen as the test reaction to examine the catalytic activity of the Au-CeO 2 Janus-like nanoparticles. It is found that Au-CeO 2 Janus-like nanoparticles show higher activity than that of CeO 2 nanoparticles or Au-CeO 2 composite nanoparticles. The increased catalytic activity of Au-CeO 2 Janus-like nanoparticles is attributed to the exposed Au core on one side of the Janus nanoparticles and the Au-CeO 2 heterointerfaces. [ABSTRACT FROM AUTHOR]