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A crosslinked amphiphilic copolymer [poly(ethylene glycol) (PEG)-poly(methyl methacrylate) (PMMA)-ethylene glycol dimethacrylate (EGDM)] composed of PMMA, PEG, and crosslinking units (EGDM) was synthesized by atom transfer radical polymerization to develop micelles as carriers for hydrophobic drugs. By adjusting the molar ratio of methyl methacrylate and EGDM, three block copolymer samples (P0, P1, and P2) were prepared. The measurement of gel permeation chromatography and 1 H-NMR indicated the formation of crosslinked structures for P1 and P2. Fluorescence spectroscopy measurement indicated that PEG-PMMA-EGDM could self-assemble to form micelles, and the critical micelle concentration values of the crosslinked polymer were lower than those of linear ones. The prepared PEG-PMMA-EGDM micelles were used to load doxorubicin (DOX). The drug-loading efficiencies of P1 and P2 were higher than that of P0 because the crosslinking units enhanced the micelles' stability. With increasing drug-loading contents, DOX release from the micelles in vitro was decreased, and in the crosslinked formulations, the release rate was also slower. An in vitro release study indicated that DOX release from the micelles for the linear samples was faster than that for crosslinked micelles. The drug feeding amount increased and resulted in an increase in the drug-loading content, and the loading efficiency decreased. These PEG-PMMA-EGDM micelles did not show toxicity in vitro and could reduce the cytotoxicity of DOX in the micelles; this suggested that they are good candidates as stable drug carriers. V C 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39623.

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The polyphosphazene (PZN) with dual functions of “surface modifier” and “flame‐retarded synergistic agent” was introduced as the “shell” in order to improve the compatibility and flame retardancy property of NiCo‐based bimetallic hydroxide (NiCo‐BH). In this study, a novel core‐shell nanostructures flame retardants (PZN@NiCo‐BH) was synthesized, the resulting PZN@NiCo‐BH was further incorporated into PP to investigate the mechanical property, flame retardancy and smoke suppression performance. Chemical structure and morphology of PZN@NiCo‐BH were characterized by XRD, FT‐IR, SEM, TEM, WCA and TG‐DTG, and the results have shown the successful preparation of the well‐designed PZN@NiCo‐BH. Moreover, LOI, UL‐94 and cone calorimetry measurements results further confirmed the superb flame retardancy and smoke suppression of the synthesized PP/PZN@NiCo‐BH composites with a LOI value of 29.5% in the UL‐94 V‐0 rating, and 56.3% reduction in total smoke production (TSP). Meanwhile, based on the analysis of the combustion residues, possible mechanism of flame retardancy was also proposed.