A general method was developed for the synthesis of Fe 3 O 4 @polymer microspheres with well-defined coreÀ shell structure and various functional groups and strong magnetization through a facile in situ distillationÀprecipitation polymerization. In this approach, the as-prepared Fe 3 O 4 microspheres were directly coated by a polymer shell through the hydrogen bond interaction between the Fe 3 O 4 micropsheres and oligomer without any surface modification. Moreover, hydrophilic or hydrophobic monomer or even their comonomers with different functional groups such as carboxyl, hydroxyl, amide, and ester were facilely encapsulated onto the surface of the magnetite microspheres. The thickness of the polymer shell layer was tuned by the feed of monomer amount. As for application, Fe 3 O 4 @P(MBAAm-co-MAA) microspheres that contained carboxyl groups were used as a magnetic catalyst support to load a series of metallic nanoparticles such as Ag, Pt, and Au. These strong magnetic microspheres were characterized by transmission electron microscopy, X-ray diffraction, Fourier-transform infrared spectra, thermogravimetric analysis, and vibrating sample magnetometry.

SiO(2)/poly(ethyleneglycol dimethacrylate) (PEGDMA) rattle-type microspheres loaded with tiny sized gold nanoparticles (~2 nm) were prepared through a facile and novel method. Catalyzed reduction of 4-nitrophenol with NaBH(4) demonstrated that this rattle-type microsphere possessed high catalytic efficiency.

The specificity hydrogen bonds of nucleobase pairs are the main linker in DNA and RNA. Compared with conventional covalent‐linking polymer to prepare nanoparticles (NPs), nucleobase pairs as supermolecule linker to assemble the bionic copolymer NPs may be an innovative way. Adenine (A) modified poly(ε‐caprolactone) and thymine (T) modified poly(ethylene glycol) are prepared to assemble multiple hydrogen bonds linked NPs in situ. The introduction of multiple hydrogen bonds into NPs results in a unique method to prepare NPs replacing the conventional assemble method. These NPs exhibit narrow size distribution with the average diameter of 45 nm under pH 7.4. The chemical shift of T NH proton moves from 11.30 to 11.05 ppm with increasing temperature from 25 to 80 °C, and the same phenomenon also appears in A NH2 proton resonance, which demonstrate the existence of hydrogen bonds. The low cytotoxicity of NPs is confirmed by MTT assay using MCF7 tumor cells. Collectively, the novel method opens the possibilities to combine bionics in assembling small size nanoparticles.

Many efforts have been devoted to maintaining the water content at a constant level in water retention proton exchange membranes, especially under a low humidity. It is necessary to develop a method for enhancing the water retention with a stable dynamic water behavior. Herein, humidity responsive double-shelled hollow spheres (DSHSs) were incorporated into a sulfonated poly(ether ether ketone) (SPEEK) matrix membrane to simultaneously enhance its water retention and improve its dynamic water behavior. The water retention of the DSHS incorporated SPEEK membrane was considerably increased compared to that of the SPEEK membrane due to the presence of a central cavity and gap between the inner and outer shell of the DSHSs. The humidity responsive DSHSs could rapidly adjust the water distribution within the SPEEK matrix and compensate the water evaporated under a low humidity, which is similar to the function of a vacuole in plant cells. As a result, the dynamic water behavior of the SPEEK/DSHS hybrid membranes was significantly improved. As a benefit from this, a continuous water network in the hybrid membranes could be maintained for a long time to enhance the proton conductivity of the hybrid membranes under a low humidity. A mechanism was proposed for the interpretation of these phenomena. The nanostructure of the hybrid membranes was studied by smallangle X-ray scattering (SAXS) and field emission scanning electron microscopy (FESEM).

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