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The novel and well-defined supramolecular amphiphilic star-branched copolymer poly((caprolactone)-star-(poly(2-N,N-dimethylamino)ethylmethacrylate) 7 (PCL-(PDMAEMA) 7 ) with a porphyrin core was prepared via the combination of ring-opening polymerization (ROP), atom transfer radical polymerization (ATRP), and supramolecular host-guest inclusion complexation. After reaction of PDMAEMA with excess 1,3-propane sultone, the quaternized star-PCL-(PDMAEMA) 7 was obtained. The amphiphilic star-PCL-(PDMAEMA) 7 and quaternized star-PCL-(PDMAEMA) 7 can selfassemble into spherical nano-micelles by directly dissolving in water. This thermoresponsive micelles solution shows a transition from a lower critical solution temperature (LCST) of star-PCL-(PDMAEMA) 7 to an upper critical solution temperature (UCST) of quaternized star-PCL-(PDMAEMA) 7 , indicating that the LCST-UCST transition of micellar solutions can be accomplished by the transition of PDMAEMA to quaternized PDMAEMA. Due to the presence of porphyrin molecules in the micelles core, the micelle solutions present obvious fluorescence and the fluorescent intensity can be adjusted by altering the temperatures. For the star-PCL-(PDMAEMA) 7 micelle solution, the fluorescent intensity decreases with the increase of temperature, while the fluorescent intensity increases with the increase of temperature for the quaternized star-PCL-(PDMAEMA) 7 micelle solution, indicating unique temperature-fluorescence responsive behavior.

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How to predict the bandgap size of graphene antidot lattices (GALs) is a key problem in the field of graphene-based nanoelectronics. Here, we have obtained the universal rules on bandgap opening/closing of GALs with zigzag-edged hexagonal holes (ZH-GALs), as well as the means to control the bandgap size. In the simple case that the electronic property depends on the choice of the supercell, the quantitative relationship between Eg and the density/diameter of antidots is fitted. Turning to complex structures, we reveal that the bandgap opening in ZH-GALs results mainly from the intervalley scattering. In this interpretation, according to their relative position, the antidots can be divided into three categories. A relatively large bandgap appears in ZH-GALs, only when the numbers of the three categories are unequal. This could be explained based on a mechanism similar to diffraction. A formula according to the explanation is provided to estimate the bandgap, which can be used to predict the electronic properties of GALs and guide the design of semiconductor and photoelectronic devices based on GALs.

An amphiphilic PCL-SS-PDMAEMA copolymer was synthesized by the combination of ring-opening polymerization (ROP) and atom transfer radical polymerization (ATRP) using a new disulfide functionalized double-head initiator with both terminal hydroxyl and bromine groups. Based on the self-assembly of the PCL-SS-PDMAEMA copolymer with oleic acid modified Fe 3 O 4 nanoparticles in aqueous solutions, magnetic PCL-SS-PDMAEMA/Fe 3 O 4 complex micelles with a saturation magnetization of 10.20 emu g À1 were prepared. The investigation of magnetothermal properties of the magnetic complex micelles showed that the temperature of the magnetic micellar systems increased in the alternating magnetic field (AMF) and the increasing rate and steady-state temperature could be adjusted through altering the magnetic flux density.Benefitting from the thermal response of PDMAEMA and redox response of the disulfide bond, the magnetic complex micelles presented obvious temperature-and redox-responsive properties. The R h of the magnetic complex micelles would decrease when the micellar solutions were heated. And when DTT was added into the magnetic micellar systems, the distributions of R h broadened with the emergence of aggregates. Due to the magnetic, magnetothermal, temperature-and redox-responsive properties, the magnetic complex micelles were used as a carrier for drug delivery systems. Doxorubicin (DOX), an anticancer drug, was used as a model drug and loaded into the magnetic complex micelles. The magnetic complex micelles presented good properties for controlled release. The release rate and level could be controlled by adding an external AMF and altering the DTT concentration.

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An amphiphilic Py-PCL-b-POEGMA copolymer was prepared by the combination of ring-opening polymerization (ROP) and atom transfer radical polymerization (ATRP). Based on the host-guest inclusion complexation of a-CD with densely grafted chains of the POEGMA shell in Py-PCL-b-POEGMA micelles, supramolecular micellar hydrogels were obtained by adding a-CD into Py-PCL-b-POEGMA micellar solutions. Resulting from the dissociation of a-CD from the ICs upon heating, the Py-PCLb-POEGMA IC-based supramolecular hydrogels presented thermo-responsive properties. As they were heated, the IC-based hydrogels underwent gel-sol transformation because of the breakage of the physical cross-links. Benefiting from the fluorescent pyrene group in the Py-PCL-b-POEGMA copolymer, the system showed fluorescent properties. And the fluorescent intensity decreased obviously and regularly during the sol-gel transformation process, which makes it possible to detect the sol-gel transformation through sensing the fluorescent intensity of the system. Due to the biodegradable and biocompatible properties, the IC-based hydrogels were used as carriers for delivery systems. The hydrogels showed good properties for controlled release, and the release rate and level can be controlled by temperature.