We here report the synthesis and characterization of a complex polymeric architecture based on a block copolymer with a cylindrical brush block and a single-chain polymeric nanoparticle block folded due to strong intramolecular hydrogen-bonds. The self-assembly of these constructs on mica surfaces was studied with atomic force microscopy, corroborating the distinct presence of block copolymer architectures.

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A series of 10- and 20-arm starlike block copolymers containing inner soft poly(n-butyl acrylate) (PBA) block and outer hard poly(methyl methacrylate) (PMMA) block were synthesized by atom transfer radical polymerization (ATRP). Short macroinitiators for preparation of starlike copolymers, poly(2-bromoisobutyryloxyethyl acrylate) (PBiBEA) with degree of polymerization DP = 10 and 20, was prepared by ATRP of trimethylsilyloxyethyl acrylate (HEATMS) and subsequently esterified. Partial star coupling during the star extension with PMMA blocks was observed, and the coupling increased with increasing number of arms and arm length. Phase-separated morphologies of cylindrical hard PMMA block domains arranged in the soft PBA matrix were observed by atomic force microscopy and small-angle X-ray scattering. The mechanical and thermal properties of the copolymers were also thoroughly characterized, and their thermoplastic elastomer behavior was studied. Tensile strength of the starlike copolymers was considerably higher compared to linear and three-arm stars with similar compositions.

The design and control of polymeric nanoscale network structures at the molecular level remains a challenging issue. Here we construct a novel type of polymeric nanoscale networks with a unique microporous nanofiber unit employing the intra/interbrush carbonyl cross-linking of polystyrene side chains for well-defined cylindrical polystyrene molecular bottlebrushes. The size of the side chains plays a vital role in the tuning of nanostructure of networks at the molecular level. We also show that the as-prepared polymeric nanoscale networks exhibit high specific adsorption capacity per unit surface area because of the synergistic effect of their unique hierarchical porous structures. Our strategy represents a new avenue for the network unit topology and provides a new application for molecular bottlebrushes in nanotechnology.

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Summary: In situ synthesis of poly(methyl methacrylate) (PMMA) nanocomposites by photopolymerization using organophilic montmorillonite (MMT) as the layered clay is reported. MMT clay was ion exchanged with N‐phenacyl, N,N‐dimethylanilinium hexafluoro phosphate (PDA) which acts as both suitable intercalant‐ and photo‐initiator. These modified clays were then dispersed in methyl methacrylate (MMA) monomer in different loading degrees to carry out the in situ photopolymerization. Intercalation ability of the photoinitiator and exfoliated nanocomposite structure were evidenced by both X‐ray diffraction (XRD) spectroscopy and transmission electron microscopy (TEM). Thermal properties and morphologies of the resultant nanocomposites were also studied.Schematic representation of clay‐PMMA nanocomposites by photoinitiated radical polymerization.imageSchematic representation of clay‐PMMA nanocomposites by photoinitiated radical polymerization.

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