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We have demonstrated that nanoporous gold (AuNPore) is an efficient catalyst to promote the selective diboration of methylenecyclopropanes (MCPs) in a heterogeneous manner. Notably, the diboration takes place via a regioselective cleavage of the distal bond of the cyclopropane ring exclusively by AuNPore without using any additives. The experimental results and computational studies of the mechanism indicate that the present diboration proceeds through the formation of a relatively stable trimethylenemethane intermediate on the AuNPore surface with increased negative charges on trimethylene carbons, giving rise to the subsequent diboration selectively.

In this study, Ce ions were doped into the crystal lattice of TNTs and bonded to O, which resulted in the generation of CeO2 and expansion of the lattice defects of TNTs. Then, TNTs and Ce doped TNTs (Ce-TNTs) were coated on the surface of bamboo fibre materials by layer-by-layer self-assembly to refine the flame retardant performance of the materials. Scanning electron micrographs (SEM) and energy disperse spectrum (EDS) analysis indicated that the TNTs and Ce-TNTs were uniformly distributed on the surface of the bamboo fibre materials, and the Ti content reached ∼3.90 wt% and ∼3.70 wt%, respectively. Results from the cone calorimeter test showed that the flame retardant performance of the bamboo fibre materials was enhanced after the TNTs were coated on the surface of the materials (TNTs@Fibre). When Ce-TNTs were used as substitute for TNTs, the flame retardant performance of the Ce-TNTs@Fibre materials was further improved. The TTI and FPI were prolonged to 39.7s and 0.073 m2 s/kW, and the av-HRR and THR were reduced to 126.9 kW/m2 and 35.54 MJ/m2 respectively. Moreover, pSEA, TSP and pSPR were decrease to 292.5 m2/kg, 3.70 m2 and 0.039 m2/s. DSC and TG results demonstrated that the TNTs and Ce-TNTs enhanced the both thermostability and thermo oxidative stability of the materials.

Submicrometer-sized magnetite colloid nanocrystal clusters (MCNCs) provide a new avenue for constructing uniformly sized and highly magnetic composite submicrospheres. Herein, a facile and eco-friendly method is described for the synthesis of Fe3O4@poly(acrylic acid) (PAA)/chitosan (CS) core-shell submicrospheres using MCNCs bearing carboxyl groups as the magnetic cores. It is based on the self-assembly of positively charged CS chains on the surface of the oppositely charged MCNCs dispersed in the aqueous solution containing acrylic acid (AA) and a cross-linker N,N'-methylenebis(acrylamide) (MBA), followed by radical induced cross-linking copolymerization of AA and MBA along the CS chains. The resulting polymer shell comprises a medium shell of cross-linked PAA/CS polyelectrolyte complexes and an outer shell of protonated CS chains. It was found that the shell thickness could be tuned by varying either the concentration of radical initiator or the molar ratio of AA to aminoglucoside units of CS. To the surface of thus obtained Fe3O4@PAA/CS particles, Au nanoparticles, a variety of functional groups such as fluorescein, carboxyl, quaternary ammonium, and aliphatic bromide, and even functional polymer chains were successfully introduced. Therefore, such Fe3O4@PAA/CS submicrospheres may be used as versatile magnetic functional scaffolds in biorelated areas like bioseparation and medical assay, considering the unique features of CS like nontoxicity and biocompatibility.

Surface imprinting over nanosized support materials is particularly suitable for protein templates, considering the problems with mass transfer limitation and low binding capacity. Previously we have demonstrated a strategy for surface protein imprinting over vinyl-modified silica nanopartiles with lysozyme as a model template by polymerization in high-dilution monomer solution to prevent macrogelation. Herein, the synthesis process was further studied toward enhancement of the imprinting performance by examining the effect of several synthesis conditions. Interestingly, the feed crosslinking degree was found to have a great impact on the thickness of the formed imprinting polymer layers and the recognition properties of the resulting imprinted materials. The imprinted particles with a crosslinking degree up to 50% showed the best imprinting effect. The imprinting factor achieved 2.89 and the specific binding reached 23.3 mg g −1 , which are greatly increased compared to those of the lowly crosslinked imprinted materials reported previously. Moreover, the relatively high crosslinking degree led to no significant retarding of the binding kinetics to the imprinted particles, and the saturated adsorption was reached within 10 min. Therefore, this may be a promising method for protein imprinting.

Fe 3 O 4 @polydivinylbenzene (PDVB) submicrospheres were prepared via distillation–precipitation polymerization of DVB in the presence of submicron magnetite colloid nanocrystal clusters (MCNCs) as seeds. The surface of the MCNCs was modified with vinyl groups before PDVB encapsulation. The resulting Fe 3 O 4 @PDVB particles showed a well-defined core–shell structure, and the shell thickness could be readily controlled by the DVB dosage. A lowly cross-linked poly(methacrylic acid) (PMAA) layer could be further coated onto the highly cross-linked PDVB shell via a second-stage DPP process, suggesting the presence of residual vinyl groups on the surface of the Fe 3 O 4 @PDVB particles. The hybrid particles showed rather high magnetization and near superparamagnetism, hence capable of easy magnetic separation.

Submicron-sized superparamagnetic magnetite colloid nanocrystal clusters (MCNCs) composed of many interconnected tiny Fe3O4 nanoparticles provide a new avenue for constructing highly magnetic polymer submicrospheres for biotechnological and medical applications. Herein, a facile and efficient method is described for the synthesis of Fe3O4@poly(methacrylic acid) (PMAA) core–shell submicrospheres using the MCNCs modified with polymerizable vinyl groups as the submicronic cores. The controlled encapsulation of the MCNCs with PMAA shells was achieved via precipitation polymerization mediated by a reversible addition–fragmentation chain transfer (RAFT) agent. A variety of factors influencing the formation of PMAA layers were examined, such as the loading amounts of the magnetic seeds and monomers, polymerization time, and the MCNCs’ surface chemistry. Compared with previous approaches, much higher seed dosage could be employed in the polymerization system without leading to significant particle conglutination. The shell thickness was readily tailored via varying two synthesis parameters, that is, monomer dosage and reaction time. The resulting hybrid particles showed high saturation magnetization and pH responsiveness. Also, this method was successfully extended to coating other hydrophilic polymer shells over the MCNCs and hence may be a general way for the synthesis of magnetic polymer submicrospheres.