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Fig. 1 (a) UV-VIS absorption spectra of monomer 3c and polymers 5a and 5b in THF solution and (b) emission spectra of monomer 3c and polymers 5a and 5b in THF solution (465 nm excitation); (-) monomer 3c, (----) polymer 5a, (-) polymer 5b

Recently a great effort has been devoted to the design and synthesis of large porphyrin arrays including dendrimers, 1 linear oligomers, 2 and polymers. 3,4 These macromolecular, chromophoric structures have a variety of uses in the study of electron and energy transfer and potential application to solar energy conversion, 2 catalysis, nonlinear optics materials, 3a sensors, and molecular wires. 3c Though porphyrin macromolecules have found increasing applications in many areas, [1][2][3][4] there are few porphyrin polymers in which the chromophoric units are linked within an extended conjugated polymer. More significantly, synthetic strategies that provide for systematic variation of the distance between the chromophoric units within polymeric systems have not been reported. Porphyrin polymers are also typically insoluble in common organic solvents, 3 limiting both characterization and application. Here we report the synthesis, characterization, and preliminary energytransfer dynamics of a new series of conjugated polymers in which porphyrin units are linked by oligophenylenevinylenes of different, controllable lengths.The porphyrin polymers described here offer several advantages for photoinduced electron-transport applications: (1) The polymers are highly soluble in common organic solvents and can be processed into optical quality thin films from solution at room temperature.(2) The porphyrin subunits have tunable photophysical and electronic properties. (3) The extended conjugation of the system, when the porphyrin rings are coplanar with the oligophenylenevinylene bridge, 5 provides for potential electrical conductivity in the charged state. (4) The electrochemical properties of the porphyrins can be selected to provide for long-range charge-transport and storage investigations. Given the similarity of poly-(phenylenevinylene) (PPV) to the bridges used here, these investigations may provide insight into future development of more traditional LED or conducting materials. 6

We report a preparation method for the synthesis of monodisperse magnetic polymer/silica hybrid microspheres using polymer microspheres incorporated with magnetic nanoparticles as a novel template. Monodisperse, hierarchically mesoporous, silica microspheres embedded with magnetic nanoparticles were successfully fabricated after the calcination of the hybrid microspheres. The magnetic nanoparticles were encapsulated in silica and distributed over the whole area of the porous microspheres without leakage. The resulting inorganic materials possess highly useful properties such as high magnetic nanoparticle loading, high surface area, and large pore volumes. The hierarchically mesoporous magnetic silica microspheres resulted in a high bovine serum albumin (BSA) protein adsorption capacity (260 mg/g) and a fast adsorption rate (reaching equilibrium with 8 h).

A novel method for the preparation of monodisperse porous silica microspheres with controllable morphology and structure is reported. The starting porous polymer microspheres were first functionalized with ethylenediamine (EDA) to generate amino groups. Subsequently, silica nanoparticles were deposited in the porous polymer microsphere to form polymer/silica hybrid microspheres via a modified sol‐gel process in the presence of tetra‐n‐butylammonium bromide (TBAB) or tetramethyl ammonium hydroxide (TMAH). Upon calcination of the polymer/silica hybrid microspheres, the porous silica microspheres were obtained. The morphology, inner structure, and properties of the porous silica microspheres were studied by field emission scanning electron microscope, Fourier transform infrared spectroscopy, thermogravimetric analysis, and mercury intrusion method. The results show that the presence of TBAB or TMAH in the process not only prevents the agglomeration of the hybrid microspheres, but also governs the controllable morphology from a porous inner structure to a hollow‐cage structure. The obtained porous silica microspheres exhibit no shrinkage from the polymer microspheres with a yield of around 98%. These porous silica microspheres have potential applications in the fields of chromatography, catalyst, and biology. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012