We report a new macromolecular architecture of dual functional block copolymer brushes on commercial thin-film composite (TFC) membranes for integrated "defending" and "attacking" strategies against biofouling. Mussel-inspired catechol chemistry is used for a convenient immobilization of initiator molecules to the membrane surface with the aid of polydopamine (PDA). Zwitterionic polymer brushes with strong hydration capacity and quaternary ammonium salt (QAS) polymer brushes with bactericidal ability are sequentially grafted on TFC membranes via activators regenerated by electron transfer-atom transfer radical polymerization (ARGET-ATRP), an environmentally benign and controlled polymerization method. Measurement of membrane intrinsic transport properties in reverse osmosis experiments shows that the modified TFC membrane maintains the same water permeability and salt selectivity as the pristine TFC membrane. Chemical force microscopy and protein/bacterial adhesion studies are carried out for a comprehensive evaluation of the biofouling resistance and antimicrobial ability, demonstrating low biofouling propensity and excellent bacterial inactivation for the modified TFC membrane. We conclude that this polymer architecture, with complementary "defending" and "attacking" capabilities, can effectively prevent the attachment of biofoulants and formation of biofilms and thereby significantly mitigate biofouling on TFC membranes.

A key challenge of photoregulated living radical polymerization is developing efficient and robust photocatalysts. Now carbon dots (CDs) have been exploited for the first time as metal-free photocatalysts for visible-light-regulated reversible addition-fragmentation chain-transfer (RAFT) polymerization. Screening of diverse heteroatom-doped CDs suggested that the P- and S-doped CDs were effective photocatalysts for RAFT polymerization under mild visible light following a photoinduced electron transfer (PET) involved oxidative quenching mechanism. PET-RAFT polymerization of various monomers with temporal control, narrow dispersity (Đ≈1.04), and chain-end fidelity was achieved. Besides, it was demonstrated that the CD-catalyzed PET-RAFT polymerization was effectively performed under natural solar irradiation.

Since it was fi rst successfully prepared as a true two-dimensional nanomaterial, graphene has attracted tremendous attention for its unique structure and outstanding properties. [ 1 , 2 ] Graphene is one of the best candidates for numerous applications in functional devices such as gas sensors, [ 3 ] photovoltaics, [ 4 ] and fi eld-effect transistors. [ 5 ] The versatile approach of chemical modifi cation on the graphene basal planes or edges affords nanomaterials with additional novel functions. [ 6 ] If chemically modifi ed graphene is used as a fi ller, the electrical, thermal, and mechanical properties of polymer-based nanocomposites can be dramatically enhanced at a very low fi ller content. [ 7 , 8 ] Recently, the optical properties of single-layered graphene have aroused considerable research interest. [9][10][11][12][13] Although the refl ection and transmission of graphene have been intensively studied, little is known about the effect of graphene on the optical properties of the nanocomposites. Graphene has a two-dimensional (2D) ordered structure with unique electronic band structure, in which the conduction band touches the valence band at two points in the Brillouin zone. [ 9 , 10 ] Electrons in 2D structures behave like massless Dirac fermions and could show unique interactions with electromagnetic fi elds. Graphene possesses visual transparency, defi ned by the fi ne structure constant, with high transparency (97.7%) and refractive index (2.6-3) in the visible light range. [9][10][11][12][13] In view of these unique characteristics, the interaction between light and the nanocomposite fi lms could be a subject with great scientifi c signifi cance, and the results could be used to improve upon conventional polymers and other organic materials for optical applications.In this Communication, we report the preparation of singlelayered graphene grafted with azo polymer brushes and its interesting use to signifi cantly enhance the diffraction efficiency (DE) of photoinduced surface-relief gratings (SRGs) on azo molecular glass fi lms. The chemical structures of the functionalized graphene (G-PCN) and azo molecular glass (TrAz-CN) used in this work are shown in Figure 1 . Azobenzene and its derivatives are well-known for their reversible trans-cis isomerization induced by light irradiation. [ 14 ] Polymers containing azobenzene or its derivatives (azo polymers for short) have been intensively investigated for their photoresponsive properties and potential applications in diffractive optical elements, information storage, optical switching, nonlinear optics, sensors, and actuators. [ 15 , 16 ] SRG formation is a reversible surface modulation related to mass transport induced by irradiation with interfering laser beams. [ 17 , 18 ] It can be used as a one-step photofabrication method to prepare various surface patterns. More recently, amorphous molecular materials containing azo chromophores have also been used for SRG studies, which show a fast SRG forming rate and large surface modulation. [19][20][2...

Over the last few years, following a trend to miniaturization found in many fields of materials science, micron-sized liquid crystalline elastomer (LCE) actuators have been described, with the aim to apply them in such domains like responsive surfaces, microfluidic devices or microsensors. The preparations of the micron-sized LCE actuators involve plenty of cuttingedge, advanced technologies such as soft lithography, microfluidic, microprinting or photomasking. In this highlight, we describe the most striking results obtained in the domain of micron-sized LCE-based responsive systems.

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and 13 C NMR spectra, 29 Si solid-state NMR spectra, thermogravimetric (TG) curves. See

Surface-initiated activators regenerated by electron transfer atom transfer radical polymerization (ARGET ATRP) integrated with mussel-inspired polydopamine (PDA) chemistry was, for the first time, employed for controlled grafting of poly­(glycidyl methacrylate) (PGMA) brushes from carbon nanotubes (CNTs). The strategy initially involved deposition of a PDA layer by spontaneous self-polymerization, which is a benign and nonsurface specific way for anchoring 2-bromoisobutyryl bromide to form initiators on the CNTs. Dense and uniform PGMA brushes were then grown via ARGET ATRP using low concentration of Cu catalyst in different solvents. With abundant highly reactive epoxy groups, the PGMA-grafted CNTs could serve as a versatile platform for further modification or functionalization. Ethylenediamine ligands were facilely introduced, imparting the functionalized CNTs with record-high adsorption ability toward uranium ions among CNTs composites. The integrated strategy combining surface-initiated ARGET ATRP technique and PDA chemistry would provide new opportunities for surface engineering of nanomaterials for advanced applications.

A unique way to fabricate hollow microspheres by using an amphiphilic azo homopolymer (BP-AZ-CA) and photoinduced deformation behavior of the hollow structures in the solid state are reported.