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A new approach to self-assembly of polymer blends in solution was studied by dynamic light scattering and transmission electron microscopy. Stable isolated particles and their clusters were obtained by dropping sulfonated polystyrene/THF solution into poly(4-vinyl pyridine)/methanol solution. The particles and clusters are stabilized by soluble poly(4-vinyl pyridine). The concentration of poly(4-vinyl...
The layer-by-layer self-assembly of polyaniline (PAN) and polyacrylic acid (PAA) has been accomplished via the alternate spontaneous adsorption of base-type PAN from its dilute N-methylpyrrolidinone solution and PAA from its aqueous solution based on the acid–base reaction of PAN and PAA. The thickness of the films can be manipulated at nanometer scale by the concentration of PAN solution and recycling...
Aqueous solutions of the triblock copolymer poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) EO13PO30EO13 (Pluronic L64) were investigated over a wide concentration range (20–100%, (w/w) polymer) in the micellar, liquid crystalline and reverse micellar phases, using electron spin resonance (ESR) spectroscopy of spin probes. A series of amphiphilic nitroxide spin probes based on...
The ultrathin films with nanometre control over thickness and multilayered structures of polypyrrole (PPY) were manufactured by in-situ self-assembled technique. A controlled thickness of PPY was deposited on polyanion, poly(styrene sulfonate) (PSS) surfaces as a function of time; previously PSS had been deposited on various substrates (glass, mica, indium–tin-oxide coated glass plates). Later, alternate...
Self-assembled films of Poly(o-ethoxyaniline) (POEA) doped with HCl alternated with sulfonated lignin (SL) were successfully produced under different pHs and their kinetics of formation studied. The adsorption at lower pHs is faster due to the greater electrostatic attraction between the POEA and the SL covered substrate, but a lower amount of POEA is deposited due to charge repulsion of additional...
Two functional crown ether initiator, bis[4'-(2-bromobutyryl)]dibenzo-18-crown-6 (BBDC) was synthesized through the condensation of dibenzo-18-crown-6 with 2-bromobutyric acid in the presence of polyphosphoric acid. Atom transfer radical polymerizations of styrene (St), methyl acrylate, methyl methacrylate and butyl acrylate were carried out in bulk to produce the polymers with well-controlled molecular...
Small angle neutron scattering was used to in situ study the aggregated structures formed in the course of the polymerization of butadiene and isoprene in deuterated n-heptane. The samples were designed to have equal degrees of polymerization. These measurements showed, at low Q, that the start of the butadiene propagation event was accompanied by the presence of highly extended large-scale structures...
We present the results of Monte Carlo simulations of self-assembly in melt of pseudo-block copolymer formed through the association of associating polymer chains with attractive end-groups (sticker sites). Complexities of the phase structures result from these pseudo-block copolymers strongly depend on parameters, such as attractive interaction strength between two stickers and chain length of associating...
Di- and triblock copolymers of poly(ethylene oxide) (PEO) and poly(dl-valine-co-dl-leucine) were synthesized by ring-opening polymerization of N-carboxyanhydride (NCA)s of dl-valine and dl-leucine initiated by amine-terminated PEOs. The resulting block copolymers were characterized by 1HNMR, FT-IR, DSC, and wide-angle X-ray diffraction (WAXD). Differential scanning calorimeter revealed that the melting...
Block copolymers (BCPs) have received great attention for the past 40 years but only within the past decade have they been seriously considered for nanotechnological applications. Their applicability to nanotechnology stems from the scale of the microdomains and the convenient tunability of size, shape, and periodicity afforded by changing their molecular parameters. The use of the tensorial physical...
ABA type triblock amphiphilic polyelectrolyte consisting of poly(methyl methacrylate-block-methacrylic acid-block-methyl methacrylate) (P(MMA-b-MAA-b-MMA)) was synthesized by atom transfer radical polymerization technique and the self-assembly behavior of the polymers in aqueous solution was studied over the course of neutralization. Combination of potentiometric and conductometric titrations along...
A series of well-defined ABA triblock copolymers of poly(methyl acrylate)-polystyrene-poly(methyl acrylate) (PMA-b-PS-b-PMA) with different molecular weights were synthesized using Cl-PS-Cl as macroinitiator, CuCl/N,N,N′,N″,N″-pentamethyldiethylenetriamine (PMDETA) as catalyst system via atom transfer radical polymerization (ATRP). Amphiphilic triblock copolymer poly(potassium acrylate)-polystyrene-poly(potassium...
Highly ordered honeycomb-like macroporous films were obtained via self-assembly of a two-armed polymer with a crown ether core under controlled conditions. A possible mechanism is speculated, primarily based on the strong affinity between the crown ether cores. The pore size and arrangement are sensitive to the solvent evaporation rate and the solution concentration. Upon spontaneous drying, the pore...
This article reports reversible changes in surface morphology and surface wettability of mixed poly(methyl methacrylate) (PMMA)/polystyrene (PS) brushes with PS M n slightly lower than that of PMMA in response to combined selective solvent treatments and thermal annealing. The mixed brushes were synthesized from asymmetric difunctional initiator-terminated monolayers by controlled radical...
Cyclic threading/dethreading of novel polypseudorotaxane obtained from β-cyclodextrins and poly(amino ester), poly(BDA–DEEDA), obtained from the Michael addition polymerization of 1,4-butanediol diacrylate (BDA) and N, N′-diethyl ethylenediamine (DEEDA), was realized by adjusting pH of the aqueous solutions between ca. 9.0 and 3.2 alternatively. 1 H NMR, XRD profiles, and 13 C CP/MAS...
A novel approach was applied to prepare shell thickness controllable magnetic microsphere precursor through the self-assembly of PDMS homopolymer with PFS-b-PDMS in selective solvent and adjusting the prepared conditions of samples such as temperature and aging time. The magnetic microsphere precursor provided with adjustable dimension of shell thickness 15, 40 and 90nm, respectively, which made it...
One kind of large-size bamboo-shape nanotube from self-assembly of poly(ferrocenyldimethylsilane-b-dimethylsiloxane) (PFS-b-PDMS) block copolymer was obtained. It was found that firstly, PFS-b-PDMS formed sphere micelles and pearl-like cluster at room temperature, and then bamboo-shape nanotube formed when the solution was aged about 3 days. The formation mechanism of bamboo-shape nanotube was also...
Thin films of alternating layer composition were constructed from the polyelectrolyte complex PEDOT:PSS and the polycation PEI, using ionic self assembly (ISA). The PEI/PEDOT:PSS system displays a consistent trend in film growth, as evidenced by UV–visible spectroscopy and ellipsometry. We find that the overall density of PEDOT increases with increasing number of layers. The density of PSS during...
In this paper, hyperbranched polyesters (HPs) were synthesized in the molten state from 2,2-bis(hydroxymethyl) propionic acid (bis-MPA) and 2-ethyl-2-hydroxymethyl-1,3-propanediol (TMP) using acid catalysis. The modified hyperbranched polyesters were obtained through the chemical modification of the hyperbranched polyester cores by substituting a controlled fraction of the terminal hydroxyl groups...
We report on the rapid formation of hydrophilic silicone elastomer surfaces by ultraviolet/ozone (UVO) irradiation of poly(vinylmethyl siloxane) (PVMS) network films. Our results reveal that the PVMS network surfaces render hydrophilic upon only a short UVO exposure time (seconds to a few minutes). We also provide evidence that the brief UVO irradiation treatment does not cause dramatic changes in...
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