Abstract
Spherical molecular brushes with amphiphilic heteroarms were facilely synthesized by grafting the arms of hydrophobic 2-azidoethyle palmitate and hydrophilic monoazide-terminated poly(ethylene glycol) onto the core of alkyne-modified hyperbranched polyglycerol (HPG) with high molecular weight (M n = 122 kDa) via one-pot parallel click chemistry. The parallel click grafting strategy was demonstrated to be highly efficient (∼100%), very fast (∼ 2 h) and well controllable to the amphilicity of molecular brushes. Through adjusting the feeding ratio of hydrophobic and hydrophilic arms, a series of brushes with different arm ratios were readily obtained. The resulting miktoarms hyperbranched polymer brushes (HPG-g-C16/PEG350) were characterized by hydrogen-nuclear magnetic resonance (1H NMR), Fourier transform infrared (FT-IR) spectroscopy, gel permeation chromatography (GPC), and differential scanning calorimetry (DSC) measurements. The spherical molecular brushes showed high molecular weights up to 230 kDa, and thus could be visualized by atomic force microscopy (AFM). AFM and dynamic laser light scattering (DLS) were employed to investigate the self-assembly properties of amphiphilic molecular brushes with closed proportion of hydrophobic and hydrophilic arms. The brushes could self-assemble hierarchically into spherical micelles, and network-like fibre structures, and again spherical micelles by addition of n-hexane into the dichloromethane or chloroform solution of brushes. In addition, this kind of miktoarms polymer brush also showed the ability of dye loading via host-guest encapsulation, which promises the potential application of spherical molecular brushes in supramolecular chemistry.
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References
Zhang MF, Muller AHE. Cylindrical polymer brushes. J Polym Sci, Part A: Polym Chem, 2005, 43(16): 3461–3481
Sheiko SS, Sumerlin BS, Matyjaszewski K. Cylindrical molecular brushes: Synthesis, characterization, and properties. Prog Polym Sci, 2008, 33(7): 759–785
Gao C, Zheng X. Facile synthesis and self-assembly of multiheteroarm hyperbranched polymer brushes. Soft Mater, 2009, 5(23): 4788–4796
Knischka R, Lutz PJ, Sunder A, Mulhaupt R, Frey H. Functional poly(ethylene oxide) multiarm star polymers: Core-first synthesis using hyperbranched polyglycerol initiators. Macromolecules, 2000, 33(2): 315–320
Burgath A, Sunder A, Neuner I, Mulhaupt R, Frey H. Multi-arm star block copolymers based on epsilon-caprolactone with hyperbranched polyglycerol core. Macromol Chem Phys, 2000, 201(7): 792–797
Wan DC, Fu Q, Huang JL. Synthesis of amphiphilic hyperbranched polyglycerol polymers and their application as template for size control of gold nanoparticles. J Appl Polym Sci, 2006, 101(1): 509–514
Liu HJ, Chen Y, Shen Z, Frey H. Multiarm star polyglycerolblock-poly(HEMA) as a versatile precursor for the preparation of micellar nanocapsules with different properties. React Funct Polym, 2007, 67(2): 156–164
Turk H, Shukla A, Rodrigues PCA, Rehage H, Haag R. Watersoluble dendritic core-shell-type architectures based on polyglycerol for solubilization of hydrophobic drugs. Chem Eur J, 2007, 13(15): 4187–4196
Wan DC, Yuan JJ, Pu HT. Macromolecular nanocapsule derived from hyperbranched polyethylenimine (HPEI): Mechanism of guest encapsulation versus molecular parameters. Macromolecules, 2009, 42(5): 1533–1540
Xu SJ, Luo Y, Graeser R, Warnecke A, Kratz F, Hauff P, Licha K, Haag R. Development of pH-responsive core-shell nanocarriers for delivery of therapeutic and diagnostic agents. Bioorg Med Chem Lett, 2009, 19(3): 1030–1034
Xie MR, Dang JY, Shi JX, Han HJ, Song CM, Huang W, Zhang YQ. Synthesis and self-assembly of well-defined polymer brushes with high grafting density of hydrophobic poly(epsilon-caprolactone) and hydrophilic poly(2-(dimethylamino)ethyl methacrylate) side chains. Acta Chim Sinica, 2009, 67(8): 869–874
Xie MR, Dang JY, Han HJ, Wang WZ, Liu JW, He XH, Zhang YQ. Well-defined brush copolymers with high grafting density of amphiphilic side chains by combination of ROP, ROMP, and ATRP. Macromolecules, 2008, 41(23): 9004–9010
Li ZY, Li P, Huang JL. Synthesis of amphiphilic copolymer brushes: Poly(ethylene oxide)-graft-polystyrene. J Polym Sci, Part A: Polym Chem, 2006, 44(15): 4361–4371
Li CH, Ge ZS, Fang J, Liu SY. Synthesis and self-assembly of coil-rod double hydrophilic diblock copolymer with dually responsive asymmetric centipede-shaped polymer brush as the rod segment. Macromolecules, 2009, 42(8): 2916–2924
Huang Y, Liu Q, Zhou X, Perrier Sb, Zhao Y. Synthesis of silica particles grafted with well-defined living polymeric chains by combination of raft polymerization and coupling reaction. Macromolecules, 2009, 42(15): 5509–5517
Li YG, Zhang YQ, Yang D, Li YJ, Hu JH, Feng C, Zhai SJ, Lu GL, Huang XY. PAA-g-PPO amphiphilic graft copolymer: Synthesis and diverse micellar morphologies. Macromolecules, 2010, 43(1): 262–270
Zhang YQ, Shen Z, Yang D, Feng C, Hu JH, Lu GL, Huang XY. Convenient synthesis of PtBA-g-PMA well-defined graft copolymer with tunable grafting density. Macromolecules, 2010, 43(1): 117–125
Liu C, Zhang Y, Huang JL. Well-defined star polymers with mixed-arms by sequential polymerization of atom transfer radical polymerization and reverse addition-fragmentation chain transfer on a hyperbranched polyglycerol core. Macromolecules, 2008, 41(2): 325–331
Gao HF, Matyjaszewski K. Synthesis of low-polydispersity miktoarm star copolymers via a simple “Arm-First” method: Macromonomers as arm precursors. Macromolecules, 2008, 41(12): 4250–4257
Gao HF, Matyjaszewski K. Synthesis of molecular brushes by “grafting onto” method: Combination of ATRP and click reactions. J Am Chem Soc, 2007, 129(20): 6633–6639
Gao HF, Matyjaszewski K. Synthesis of star polymers by a combination of ATRP and the “click” coupling method. Macromolecules, 2006, 39(15): 4960–4965
Zhong L, Zhou YF, Yan DY, Pan CY. Synthesis of a multi alternatingarm-containing dendritic star copolymer by RAFT and cationic ring-opening polymerization. Macromol Rapid Comm, 2008, 29(16): 1385–1391
Killops KL, Campos LM, Hawker CJ. Robust, efficient, and orthogonal synthesis of dendrimers via thiol-ene “click” chemistry. J Am Chem Soc, 2008, 130(15): 5062–5064
Wu J, He H, Gao C. Sliding supramolecular polymer brushes with tunable amphiphilicity: One-step parallel click synthesis and self-assembly. Macromolecules, 2010, 43(17): 7139–7146
Gao C, Yan D. Hyperbranched polymers: From synthesis to applications. Prog Polym Sci, 2004, 29(3): 183–275
Zhou L, Gao C, Xu WJ. Efficient grafting of hyperbranched polyglycerol from hydroxyl-functionalized multiwalled carbon nanotubes by surface-initiated anionic ring-opening polymerization. Macromol Chem Phys, 2009, 210(12): 1011–1018
Zhou L, Gao C, Xu WJ, Wang X, Xu YH. Enhanced biocompatibility and biostability of CdTe quantum dots by facile surface-initiated dendritic polymerization. Biomacromolecules, 2009, 10(7): 1865–1874
Calderon M, Quadir MA, Sharma SK, Haag R. Dendritic polyglycerols for biomedical applications. Adv Mater, 2010, 22(2): 190–218
Kainthan RK, Muliawan EB, Hatzikiriakos SG, Brooks DE. Synthesis, characterization, and viscoelastic properties of high molecular weight hyperbranched polyglycerols. Macromolecules, 2006, 39(22): 7708–7717
Wilms D, Stiriba SE, Frey H. Hyperbranched polyglycerols: From the controlled synthesis of biocompatible polyether polyols to multipurpose applications. Accounts Chem Res, 2010, 43(1): 129–141
Kolb HC, Finn MG, Sharpless KB. Click chemistry: Diverse chemical function from a few good reactions. Angew Chem Int Ed, 2001, 40(11): 2004–2021
Lutz JF. 1,3-Dipolar cycloadditions of azides and alkynes: A universal ligation tool in polymer and materials science. Angew Chem Int Ed, 2007, 46(7): 1018–1025
Lee S, Spencer ND. Materials science — Sweet, hairy, soft, and slippery. Science, 2008, 319(5863): 575–576
Jia ZF, Zhou YF, Yan DY. Amphiphilic star-block copolymers based on a hyperbranched core: Synthesis and supramolecular self-assembly. J Polym Sci, Part A: Polym Chem, 2005, 43(24): 6534–6544
Zhou YF, Yan DY. Supramolecular self-assembly of amphiphilic hyperbranched polymers at all scales and dimensions: Progress, characteristics and perspectives. Chem Commun, 2009, 10: 1172–1188
Adeli M, Haag R. Multiarm star nanocarriers containing a poly(ethylene imine) core and polylactide arms. J Polym Sci, Part A: Polym Chem, 2006, 44(19): 5740–5749
Yan DY, Zhou YF, Hou J. Supramolecular self-assembly of macroscopic tubes. Science, 2004, 303(5654): 65–67
Ranganathan K, Deng R, Kainthan RK, Wu C, Brooks DE, Kizhakkedathu JN. Synthesis of thermoresponsive mixed arm star polymers by combination of RAFT and ATRP from a multifunctional core and its self-assembly in water. Macromolecules, 2008, 41(12): 4226–4234
Gao C, He H, Zhou L, Zheng X, Zhang Y. Scalable functional group engineering of carbon nanotubes by improved one-step nitrene chemistry. Chem Mater, 2008, 21(2): 360–370
Zhang Y, He H, Gao C. Clickable macroinitiator strategy to build amphiphilic polymer brushes on carbon nanotubes. Macromolecules, 2008, 41(24): 9581–9594
Hong HY, Mai YY, Zhou YF, Yan DY, Chen Y. Synthesis and supramolecular self-assembly of thermosensitive amphiphilic star copolymers based on a hyperbranched polyether core. J Polym Sci, Part A: Polym Chem, 2008, 46(2): 668–681
Runge MB, Lipscomb CE, Ditzler LR, Mahanthappa MK, Tivanski AV, Bowden NB. Investigation of the assembly of comb block copolymers in the solid state. Macromolecules, 2008, 41(20): 7687–7694
Hermans TM, Broeren MAC, Gomopoulos N, van der Schoot P, van Genderen MHP, Sommerdijk N, Fytas G, Meijer EW. Self-assembly of soft nanoparticles with tunable patchiness. Nat Nanotechnol, 2009, 4(11): 721–726
Zou JH, Ye XD, Shi WF. Crosslinkable vesicles self-assembled by amphiphilic hyperbranched polyester. Macromol Rapid Commun, 2005, 26(21): 1741–1745
Schappacher M, Deffieux A. Atomic force microscopy imaging and dilute solution properties of cyclic and linear polystyrene combs. J Am Chem Soc, 2008, 130(44): 14684–14689
Hans M, Mourran A, Henke A, Keul H, Moeller M. Synthesis, characterization, and visualization of high-molecular-weight poly(glycidolgraft-epsilon-caprolactone) starlike polymers. Macromolecules, 2009, 42(4): 1031–1036
Liu C, Gao C, Yan D. Honeycomb-patterned photoluminescent films fabricated by self-assembly of hyperbranched polymers13. Angew Chem Int Ed, 2007, 46(22): 4128–4131
Kramer M, Stumbe JF, Turk H, Krause S, Komp A, Delineau L Prokhorova S, Kautz H, Haag R. pH-Responsive molecular nanocarriers based on dendritic core-shell architectures. Angew Chem Int Ed, 2002, 41(22): 4252–4256
Wan DC, Fu Q, Huang JL. Synthesis of a thermoresponsive shell-crosslinked 3-layer onion-like polymer particle with a hyperbranched polyglycerol core. J Polym Sci, Part A: Polym Chem, 2005, 43(22): 5652–5660
Elmer S L, Man S, Zimmerman S C. Synthesis of polyglycerol, porphyrin-cored dendrimers using click chemistry. Eur J Org Chem, 2008, 22: 3845–3851
Kainthan RK, Mugabe C, Burt HM, Brooks DE. Unimolecular micelles based on hydrophobically derivatized hyperbranched polyglycerols: Ligand binding properties. Biomacromolecules, 2008, 9(3): 886–895
Wang SW, Zhang B, Ai P, Zhu M, Wang W, Sa ZP, Ma LN, Li YP. Chemoenzymatic synthesis amphiphilic H-shaped copolymer and its self-assembly behavior. Sci China Ser B, 2009, 39(6): 518–524
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Han, Y., Gao, C. Miktoarms hyperbranched polymer brushes: One-step fast synthesis by parallel click chemistry and hierarchical self-assembly. Sci. China Chem. 53, 2461–2471 (2010). https://doi.org/10.1007/s11426-010-4134-5
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DOI: https://doi.org/10.1007/s11426-010-4134-5