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Photo-controlled living polymerization has received great attention in recent years. However, despite the great success therein, the report on photo-controlled living cationic polymerization has been greatly limited. We demonstrate here a novel decolorable, metal-free and visible light-controlled living cationic polymerization system by using tris(2,4-dimethoxyphenyl)methylium tetrafluoroborate as the photocatalyst and phosphate as the chain transfer agent (CTA) for polymerization of 4-methoxystyrene. This polymerization reaction under green LED light irradiation shows clear living characteristics including predictable molar mass, low molar-mass dispersity (Đ = 1.25), and sequential polymerization capability. In addition, the photocatalytic system exits excellent "on-off" photo switchability and shows the longest "off period" of 36 h up to now for photo-controlled cationic polymerization. Furthermore, the residual photo-catalyst is easily deactivated and decolored with addition of a base after the polymerization. The present study has extended the photo-controlled living cationic polymerization systems with new organic photocatalysts, phosphate CTA and polymerizable monomer as well as the new properties of excellent photostability and in-situ decolored capacity. Photo-controlled living polymerization has received great attention in recent years but the reports on photo-controlled living cationic polymerization are limited. Here, the authors demonstrate a metal-free and visible light-controlled living cationic polymerization using a photocatalyst and a phosphate as the chain transfer agent for the polymerization of 4-methoxystyrene. [ABSTRACT FROM AUTHOR]

Abstract: Hierarchical solution self‐assembly has become an important biomimetic method to prepare highly complex and multifunctional supramolecular structures. However, despite great progress, it is still highly challenging to prepare hierarchical self‐assemblies on a large scale because the self‐assembly processes are generally performed at high dilution. Now, an emulsion‐assisted polymerization‐induced self‐assembly (EAPISA) method with the advantages of in situ self‐assembly, scalable preparation, and facile functionalization was used to prepare hierarchical multiscale sea urchin‐like aggregates (SUAs). The obtained SUAs from amphiphilic alternating copolymers have a micrometer‐sized rattan ball‐like capsule (RBC) acting as the hollow core body and radiating nanotubes tens of micrometers in length as the hollow spines. They can capture model proteins effectively at an ultra‐low concentration (ca. 10 n m) after functionalization with amino groups through click copolymerization. [ABSTRACT FROM AUTHOR]

In this paper, a kind of novel water-soluble chitosan-polydopamine ( CHT-PDA) nanoparticles with a hydrodynamic diameter ( Dh) around 10 nm were reported by the combination of self-polymerization of PDA and electrostatic complexation between PDA and CHT in water/ DMSO (W/D) mixture at the molar fraction of DMSO ( xDMSO = 0.37). The preparation method was efficient with a yield of 98% around. The as-prepared water-soluble CHT-PDA nanoparticles exhibited effective UV-screen ability, enhanced visible-light transmittance and good cytocompatibility via MTT assay, which might be used in transparent formulation for UV protection usage, especially in biological field including sun care application. [ABSTRACT FROM AUTHOR]

Abstract: Water-soluble titanate nanotubes (TNTs) with temperature-responsive shells were synthesized by grafting poly(N-isopropylacrylamide) (PNIPAAm) from TNTs via surface atom transfer radical polymerization (ATRP) using ATRP agent functionalized TNTs as macroinitiator. Proton Nuclear magnetic resonance spectroscopy (1H NMR), Fourier-transform infrared (FT-IR) and thermogravimetric analyses (TGA) results prove the successful graft of PNIPAAm chains from TNTs. TGA shows that the amount of PNIPAAm grown from the TNTs increased with the increase of monomer/initiator ratio. Transmission electron microscope (TEM) measurements displays the obtained TNTs-g-PNIPAAm nanohybrids have a core–shell structure of TNT cores and PNIPAAm shells. In addition, the functional nanotubes demonstrate a reversible low critical solution temperature (LCST) transition with the increase of solution temperature. The synthetic method presented here can also be extended to graft other stimuli responsive polymers from TNTs. [Copyright &y& Elsevier]

Abstract: In recent years, polymer microcapsules have attracted more and more attention because of their specific properties and applications in encapsulation and drug delivery. Great effort has been made to investigate the preparation methods, structure controls as well as the property designs for the polymer microcapsules. In this work, we reported an effective route for the preparation of poly(β-hydroxybutyrate) (PHB) and poly(lactic acid) (PLA) hollow spheres with controlled wall thickness, which involves the graft polymerization of the biodegradable polymers from the surface of silica spheres followed by removing the template cores. Nuclear magnetic resonance spectroscopy (NMR), thermal gravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and transmission electron microscope (TEM) have been used to prove the structure of the hollow sphere and the intermediates. The result reveals that with the increase of reaction time the wall thickness of the hollow sphere will increase gradually. [Copyright &y& Elsevier]

Herein, we report a new and facile method for fabricating TiO2@mesoporous carbon hybrid materials. Uniform polydopamine (PDA) layers were coated onto the surface of titanate nanotubes (TNTs) and TiO2 nanorods (TNDs) through the spontaneous adhesion and self-polymerization of dopamine during the dipping process. Core–shell mesoporous carbon nanotubes with TiO2 nanorods or nanoparticles encapsulated inside (TiO2@MC) were then obtained by transforming PDA layers into carbonaceous ones through calcination in nitrogen at 800 °C. The thickness of the mesoporous carbon layers is tens of nanometers and can be controlled by adjusting the coated PDA layers through the self-polymerization reaction time. In addition, three-layered nanocomposites of TiO2@MC@MO (MO, metal oxide) can be readily prepared by utilizing PDA layers in TNTs@PDA or TNDs@PDA to adsorb the metal ions, followed by the calcination process. [ABSTRACT FROM AUTHOR]

Abstract: A series of palmitoyl chloride-grafted hyperbranched polyglycerols were synthesized through cationic ring-opening polymerization and end-group modification. The obtained grafted copolymer of HPG-C16 possesses a hydrophilic hyperbranched polyether core and many hydrophobic alkyl arms, which shows interesting self-assembly behavior in THF and water. The results indicate that the copolymers with a relatively high alkyl grafting ratio can form unimolecular micelles in THF and will further assemble into giant vesicles around 1–10μm in THF/water mixed solvents. However, the HPG-C16 with a low alkyl grafting ratio of 15.6% can directly assemble into vesicles in THF and form micelles in water. [Copyright &y& Elsevier]