Rational design of a multi-in-one heterofunctional agent for versatile topological transformation of multisite multisegmented polystyrenes

A “seven-in-one” initiating, coupling and stimuli-labile agent is designed to achieve topological transformations with reduced, similar and enhanced molar masses.

Orthogonally clickable hyperbranched polymers: effect of reactant size and polarity on core-functionalization of peripherally jacketed HBPs

Using an orthogonally clickable strategy, the accessibility of internal allyl groups in jacketed HBPs, bearing either PEG or docosyl peripheral segments, was shown to depend both on the size and relative polarity of the reactant thiol.

Cationic Hyperbranched Polymers with Biocompatible Shells for siRNA Delivery

Cationic hyperbranched polymers (HBP) were prepared by self-condensing vinyl polymerization of an atom transfer radical polymerization (ATRP) inimer containing a quaternary ammonium group. Two types of biocompatible shells, poly(oligoethylene glycol) methacrylate (polyOEGMA) and poly(2-(methylsulfinyl) ethyl methacrylate) (polyDMSO), were grafted respectively from HBP core to form core-shell structures with low molecular weight dispersity and high biocompatibility, polyOEGMA-HBP and polyDMSO-HBP. Both of the structures showed low cytotoxicity and good siRNA complexing ability. The efficacy of gene silencing against Runt-related transcription factor 2 ( Runx2) expression and the long-term assessment of mineralized nodule formation in osteoblast cultures were evaluated. The biocompatible core-shell structures were crucial to minimizing undesired cytotoxicity and nonspecific gene suppression. polyDMSO-HBP showed higher efficacy of forming polyplexes than polyOEGMA-HBP due to shell with lower steric hindrance. Overall, the gene silencing efficiency of both core-shell structures was comparable to commercial agent Lipofectamine, indicating long-term potential for gene silencing to treat heterotopic ossification (HO).

Synthesis of hypergrafted poly[4-(N,N-diphenylamino)methylstyrene] through tandem anionic-radical polymerization of radical-inimer

In this paper, we present a tandem anionic-radical approach for synthesizing hypergrafted polymers. We prepared 4-(N,N-diphenylamino)methylstyrene (DPAMS) as a new radical-based inimer. Linear PDPAMS was prepared through anionic polymerization. Hypergrafted PDPAMS was synthesized through the self-condensing vinyl polymerization of DPAMS with linear PDPAMS. The linear backbone of PDPAMS, which incorporated latent radical initiating sites, served as a ‘hyperlinker’ to link hyperbranched side chains. The molecular weights of hypergrafted polymers increased as the length of the linear backbone chain increased. The hypergrafted structure of the resulting polymer was confirmed using a conventional gel permeation chromatograph apparatus equipped with a multiangle light scattering detector, nuclear magnetic resonance, differential scanning calorimetry, and thermogravimetric analysis. This strategy can be applied to synthesize other complex architectures based on hyperbranched polymers by changing the structure of a polymer backbone through anionic polymerization.

Facile synthesis of cylindrical molecular brushes via Lewis pair-mediated polymerization

A general strategy for creating molecular brushes via Lewis pair-mediated polymerization is described.

Construction of emission-tunable nanoparticles based on a TICT-AIEgen: impact of aggregation-induced emission versus twisted intramolecular charge transfer

AIE dot-doped silica nanoparticles, were constructed by combining AIE dots with the dye-doping silica nanoparticle method, exhibited tunable persistent emissions.

Hyperbranched Aliphatic Polyester via Cross-Metathesis Polymerization: Synthesis and Postpolymerization Modification

A novel postpolymerization modification methodology is demonstrated to achieve selective functionalization of hyperbranched polymer (HBP). Terminal and internal acrylates of HBP derived from cross-metathesis polymerization (CMP) are functionalized in a chemoselective fashion using the thiol-Michael chemistries. Model reactions between different thiols (benzyl mercaptan and methyl thioglycolate) and acrylates (n-hexyl acrylate and ethyl trans-2-decenoate) by using dimethylphenylphosphine or amylamine as the catalyst are investigated to optimize the modification protocol for HBP. High-molecular-weight HBP P0 is generated through CMP of AB₂ monomer 2, a compound containing one α-olefin and two acrylate metathetically polymerizable groups. CMP kinetics is monitored by NMR and gel permeation chromatography (GPC). Accordingly, microstructural analysis is conducted in detail, and CMP procedure is optimized. Postpolymerization modification of HBP P0 is performed via two distinguished strategies, namely one-step complete modification and sequential modification, to generate terminally and/or internally functionalized HBPs P1-P3 in a chemoselective fashion by using phosphine-initiated and/or base-catalyzed thiol-Michael chemistries. Finally, thermal stability and glass transition behaviors of HBPs P0-P3 are studied by thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC), respectively.

Post-polymerization modification reactions of poly(glycidyl methacrylate)s

Single and multiple post-polymerization modifications of poly(glycidyl methacrylate) scaffold through the nucleophilic ring-opening reactions of the pendent epoxide groups are described.

Polyphosphazene Based Star-Branched and Dendritic Molecular Brushes

A new synthetic procedure is described for the preparation of poly(organo)phosphazenes with star-branched and star dendritic molecular brush type structures, thus describing the first time it has been possible to prepare controlled, highly branched architectures for this type of polymer. Furthermore, as a result of the extremely high-arm density generated by the phosphazene repeat unit, the second-generation structures represent quite unique architectures for any type of polymer. Using two relativity straight forward iterative syntheses it is possible to prepare globular highly branched polymers with up to 30 000 functional end groups, while keeping relatively narrow polydispersities (1.2-1.6). Phosphine mediated polymerization of chlorophosphoranimine is first used to prepare three-arm star polymers. Subsequent substitution with diphenylphosphine moieties gives poly(organo)phosphazenes to function as multifunctional macroinitiators for the growth of a second generation of polyphosphazene arms. Macrosubstitution with Jeffamine oligomers gives a series of large, water soluble branched macromolecules with high-arm density and hydrodynamic diameters between 10 and 70 nm.

Group interval-controlled polymers: an example of epoxy functional polymers via step-growth thiol–yne polymerization

Here, we successfully synthesized a series of epoxy GICPs via one-step UV-triggered thiol–yne polymerization of commercial glycidyl propargyl ether and dithiols at 0 °C..

Facile synthesis of photolabile dendritic-unit-bridged hyperbranched graft copolymers for stimuli-triggered topological transition and controlled release of Nile red

Successive RAFT SCVP and ROP were used to generate novel hyperbranched graft copolymers with the ability for the photo-triggered degradation and accelerative release of hydrophobic dye.

Solution processible hyperbranched inverse-vulcanized polymers as new cathode materials in Li–S batteries

Highly soluble inverse-vulcanized hyperbranched polymers were synthesized as cathode-active materials in Li–S batteries.

Synthesis, postmodification and fluorescence properties of reduction-cleavable core-couplable miktoarm stars with a branched core

Postmodification of (PEG)_m(PCL)_n miktoarm stars with a dual-reactive branched core allowed the introduction of versatile functionalities, and the coumarin-functionalized star exhibited tunable fluorescence properties sensitive to solvent polarity and reduction stimulus.

Hyperbranched polymers: advances from synthesis to applications

This review summarizes the advances in hyperbranched polymers from the viewpoint of structure, click synthesis and functionalization towards their applications in the last decade.

AIE macromolecules: syntheses, structures and functionalities

A comprehensive review of macromolecules with aggregation-induced emission attributes is presented, covering the frontiers of syntheses, structures, functionalities and applications.