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The solution behavior and self-assembly of a ‘hairy’ heteroarm star copolymer polystyrene/poly(2-vinylpyridine) containing 20 fairly short polystyrene and 20 long poly(2-vinylpyridine) arms was studied in 1,4-dioxane–methanol mixtures and in acidic aqueous solutions. The copolymer forms reversible micelles in 1,4-dioxane–methanol mixtures. Since the conformation of the unimolecular heteroarm star...
Hexa-armed star block copolymers, s-[poly(l-lactide)-b-poly(styrene-co-N-acryloxysuccinimide)] 6 (s-[PLLA-b-poly(St-co-NAS)] 6 ) with triphenylene core have been successively prepared by the combination of ring-opening polymerization and atom transfer radical copolymerization, and they were used in the self-assembly in tetrahydrofuran, and the micelles with triphenylene core and PLLA...
Amphiphilic maleic anhydride–stearyl methacrylate (MA–SMA) random copolymer was synthesized via the free radical copolymerization and its amide was prepared through the MA moieties being reacted with morpholine. Polymers obtained were characterized by GPC and 1 H NMR. The aggregating behaviors of copolymers were investigated by first dissolving them in tetrahydrofuran (THF) and then adding...
We utilized melt polycondensation of 2,2-bis(hydroxymethyl) propionic acid (bis-MPA) and 2-ethyl-2-hydroxymethyl-1,3-propanediol (TMP) to synthesize a hyperbranched polyester core and subsequent substitution by reaction of terminal hydroxyl with benzoyl chloride in DMF in the presence of TEA as the acceptors of HCl. It has been found that well-defined macroscopic structures can be formed via hydrogen...
We present a facile method to prepare stabilized nanoparticles with pH-sensitivity and controllable dimension directly from dextran and two kinds of monomers. The synthesis was realized by a self-assembly assisted graft copolymerization of AA from dextran under the presence of crosslinker—N,N′-methylene bisacrylamide. This approach was characterized as organic solvent free, surfactant free and comparatively...
Polymeric micelles based on poly(γ-benzyl-l-glutamate)–poly(ethylene glycol) graft copolymer (PBLG-g-PEG) with various degrees of grafting and the mixtures composed of PBLG-g-PEG and poly(γ-benzyl-l-glutamate)–poly(ethylene glycol) block copolymer (PBLG-b-PEG) were prepared by the dialysis method in deionized water. Fluorescence spectroscopy and transmission electron microscope (TEM) have been used...
A novel side-chain pseudopolyrotaxanes 4 is synthesized from cucurbituril (CB[6]) and quaternized poly-4-vinylpyridine derivative 3 in water by simple stirring at room temperature. CB[6] beads are localized on hexamethylene units in side chains of 3 as found by NMR studies, and the hydrophobic and charge-dipole interactions are the driving force. The degree of threading (q/n, the average number of...
A novel percolation phenomenon with inorganic nanoparticle loading in polyamide 6-carbon based nanoparticle hybrids was identified. Percolation threshold substantially shifts to lower carbon black (CB) volume fractions in the presence of optimum concentration of chemically modified montmorillonite (organoclay) while the effective organoclay concentration can be optimized to lower the slope of percolation...
Amphiphilic ethyl cellulose (EC)-g-poly(acrylic acid) (PAA) copolymers were synthesized by atom transfer radical polymerization (ATRP). Firstly, ethyl cellulose macro-initiators with the degree of the 2-bromoisobutyryl substitution of 0.04 and 0.25 synthesized by the esterification of the hydroxyl groups remained in EC macromolecular chains and the 2-bromoisobutyryl bromides. Secondly, tert-butyl...
Core–shell–corona micelles with a thermoresponsive shell self-assembled by triblock copolymer of poly(ethyleneglycol)-b-poly(N-isopropylacrylamide)-b-polystyrene (PEG 45 -b-PNIPAM 168 -b-PS 46 ) are studied by 1 H NMR, light scattering and atomic force microscopy. The thermoresponsive triblock copolymer, which has a relatively short hydrophobic PS block, can disperse...
Well-ordered nanostructured polymeric supramolecular thin films were fabricated from the supramolecular assembly of poly(styrene-block-4-vinylpyridine) (PS-b-P4VP)(H + ) and poly(methyl methacrylate)-dibenzo-18-crown-6-poly(methyl methacrylate) (PMCMA). A depression of cylindrical nanodomains was formed by the block of P4VP(H + ) and PMCMA associates surrounded by PS. The repulsive...
We describe the synthesis and solution morphologies of poly(vinyl phenol-b-styrene) (PVPh-b-PS) micelles and the effects that changing the copolymer composition and concentration have on self-assembly structures of PVPh-b-PS in acetone (a good solvent for PVPh). These PVPh-b-PS copolymers aggregated into spherical, rod-like, and vesicular morphologies. The transformations of the PVPh-b-PS block copolymer...
We report on the nano-organization and the thermal behavior of a series of triblock copolymers composed of a central soft polydimethylsiloxane (PDMS) and two polypeptide (poly-γ-benzyl-l-glutamate) blocks. Peptide blocks with varied lengths and therefore different secondary structures (β-sheet or α-helical) were attached to the PDMS central block. These two blocks are incompatible and microphase separate...
We successfully electrochemically polymerized functional polypyrrole (PPy) nanotubes via a self-assembly process in the presence of methyl orange (MO). The influence of polymerization conditions, such as working electrodes and electrochemical polymerization time, on the tubular morphology was discussed. A fibrillar precipitate of MO formed via electric flocculation on the electrode in a neutral aqueous...
A series of semicrystalline diblock copolymers of poly(4-vinylpyridine-b-ɛ-caprolactone) (P4VP-b-PCL) have been synthesized by the living ROP of CL followed by the TEMPO polymerization of 4-VP. Depending on the relative block length and different solvent compositions, these copolymers self-assemble into different supramolecular structures in toluene/dichloromethane (DCM) solution, including spherical...
The thiol group-terminated polythiophenes were prepared via the Pd-catalyzed coupling reaction of the bromo group-terminated polythiophene derivatives and methylthiophenylboronic acid, and were mixed with the nanometer-sized gold particle to form a self-assembled network film of the alternate conjugation of the polythiophene with the gold nanoparticle. The electron microscopy and X-ray photoelectron...
Novel amphiphilic block copolymers, poly(ethylene oxide)-b-poly(p-nitrophenyl methacrylate) (PEO-b-PNPMA) with controlled molecular weights and narrow molecular weight distribution were successively synthesized by ATRP of NPMA using PEO–Br as initiator. Self-assembling of the diblock copolymer PEO 113 -b-PNPMA 28 in the different solvent mixtures yielded various morphologies of star...
In the present study we describe a synthesis and self-assembly and an in vitro evaluation of a kind of novel amphiphilic glycopeptide block copolymers as carriers for controlled drug release. Initially, an amphiphilic ABA triblock copolymer comprising polytetrahydrofuran (PTHF) as a central hydrophobic block flanked by poly(l-lysine)s (PLLs) as outer hydrophilic blocks was synthesized through the...
Self-assembly behavior of poly(γ-benzyl l-glutamate)-graft-poly(ethylene glycol) (PBLG-g-PEG) in ethanol medium was studied by transmission electron microscopy (TEM), scanning electron microscopy (SEM), laser light scattering (LLS), and circular dichroism (CD). The experimental results revealed that the conformation change of the polypeptide graft copolymer exerts marked effect on its self-association...
This paper describes the formation of fibril like aggregates from the self-assembly of block copolymer mixture (polystyrene-b-poly(4-vinylpyridine) (PS-b-P4VP) and polystyrene-b-poly(acrylic acid) (PS-b-PAA)) via interpolymer hydrogen bonding in nonselective solvent. The hydrogen bonding between P4VP and PAA in chloroform leads to the formation of complex. When all the pyridine units in P4VP were...
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