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Introduction of cross-linked structure to sulfonated polymers is an effective approach to reduce the methanol permeability of the polymers for application in direct methanol fuel cells. In this work, a crosslinkable sulfonated polymer (sPBz) has been prepared through Diels–Alder reaction with a sulfonated bismaleimide and a benzoxazine-containing bisfuran as monomers. The polymer possesses both sulfonic...
We present a scaling theory of self-assembly of triblock ter-polymer ABC in selective solvent which is good or theta for both terminal blocks A and C, but poor for the middle block B. It is demonstrated that depending on the level of incompatibility between blocks A and C of the ter-polymer, equilibrium micelle has either laterally homogeneous (mixed) or segregated (“Janus”) corona.
Synthesis of star polymers via arms-first using atom transfer radical polymerization (ATRP) and gelation in the star-polymer system were simulated using a Monte Carlo method based on the dynamic lattice liquid model (DLL). The arms-first, one-pot star synthesis consists of growing linear chains first and at specific monomer conversion subsequent addition of the cross-linker, which leads to formation...
We use dissipative particle dynamics simulations to study the interfacial properties and their relevance to the phase transitions in ternary symmetric blends. For the blend in the lamellar (LAM) state, by analyzing the distribution of inter-bilayer distances as well as the position fluctuations and correlations of bilayers, we found that the “Discrete Harmonic” theory can describe the fluctuations...
Flat ribbon-like electrospun fibers of poly(9-vinylcarbazole) (PVK)/Poly[2-methoxy-5-(2′-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV) with thickness ranging from 2 to 6 μm were prepared by electrospinning. The blue emission of the PVK fibers changed to greenish-yellow, with incorporation of MEH-PPV up to 13 wt% content. By analyzing the photoluminescence spectra, we found a significant blue shift...
Water-soluble star polymers were synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization of N-vinyl-1,2,4-triazole (NVTri), which is a non-conjugated N-vinyl monomer having an aromatic heterocycle. Four-arm poly(NVTri)s having low polydispersities and controlled molecular weights were obtained using a xanthate-type tetrafunctional chain transfer agent (CTA). Amphiphilic...
A polymer phase diagram showing the thermal degradation of poly(vinyl alcohol) (PVA) is developed by using the multivariable curve resolution (MCR) technique. Observed temperature-dependent infrared spectra are resolved into inherent states corresponding to four transient polymer phases: (i) solid state (crystalline), (ii) rubber state (amorphous), (iii) molten state (fluid), and (iv) thermal degradation...
Novel photoinitiators based on the BODIPY and boranil chromophores being able to photosensitize the iodonium salt decomposition are proposed for the cationic polymerization of epoxy, epoxy-silicone and vinyl ether monomers under exposure to laser diodes at 405, 457, 473 and 532 nm. They allow an interesting tunability of the absorption in the 400–600 nm wavelength range. Quite excellent polymerization...
The combination of the inherently complex structure of ABC triblock terpolymers with careful selection of the assembly conditions can yield an incredible array of nanostructures in solution. In this review we will highlight recent progress in the self-assembly of triblock terpolymers in solution. We will discuss various approaches that are available to tune triblock terpolymer assembly. These approaches...
The distribution of poly(acrylic acid) (PAA) in model laminates of nanocellulose and poly(vinyl alcohol) (PVOH) was investigated by FTIR chemical imaging. The method was effective in spatially discerning the three components of the composite. PAA can potentially improve the performance of nanocellulose reinforced PVOH by not only crosslinking the PVOH matrix but also improving the adhesion between...
The aggregation of chitosan (CS) has been studied as a function of concentration, degree of acetylation (DA), and degree of polymerization (DP) by means of pyrene fluorescence and rheology. Fluorescence experiments show that aggregation of CS involves hydrophobic domains (HD) which are more favoured as lower the DA and DP. Consistent with these results, the viscosity of CS solutions decreases continuously...
A pH-responsive drug delivery system was developed through facile PEGylation of commercial aliphatic dendritic polyester Boltorn ® H40 (H40) by forming the acetal linkages. Benefiting from its amphiphilic structure, the star copolymer (H40-star-MPEG) with a hydrophobic H40 core and many hydrophilic poly(ethylene glycol) (MPEG) arms was able to self-assemble into stable micelles in aqueous...
High modulus, high strength hydrogels were prepared from crosslinked copolymers of N,N-dimethylacrylamide (DMA), 2-(N-ethylperfluoro-octane sulfonamido) ethyl methacrylate (FOSM) and cinnamoyloxyethylacrylate. These FOSM-Cinnamate hybrid hydrogels were composed of a physical network and a chemical network, both attached to the same polymer backbone, and the physical network was derived from a nanophase-separated...
Although carbon nanotubes have been extensively studied since 1991, it is not clear the relations between the tubes' length and their composites' functional and mechanical performance. We in this study employed ball milling to reduce the length of multi-walled carbon nanotubes (MWNTs) from a few microns to hundreds of nm through milling for different time slots. The milled tubes demonstrated a 12...
Ternary stereocomplex (TSC) crystallization of optically active polyesters, l-configured poly(l-2-hydroxybutanoic acid) [P(l-2HB)], d-configured poly(d-2-hydroxybutanoic acid) [P(d-2HB)] and poly(d-lactic acid) (PDLA) from the melt is reported. Ternary P(l-2HB)/P(d-2HB)/PDLA blends were prepared by solution-casting to have a fixed content (50 mol%) of l-configured P(l-2HB) and different contents of...
Methacrylic anhydride was anionically polymerized for the first time by a lithium ester enolate with the aid of the bulky aluminum bisphenoxides in dichloromethane at −78 °C to afford polymers consisting of six-membered cyclized units as confirmed by NMR and IR spectroscopy, while a less bulky trialkylaluminum was ineffective. At higher temperatures, no polymeric product formed partly due to the carbonyl...
Nanometer-sized N-isopropylacrylamide (NIPA) gel particles were prepared by precipitation polymerization, and their thermosensitive swelling behaviors in water–poly(ethylene glycol) (PEG) (MW = 200, 400) systems were investigated using photon correlation spectroscopy (PCS). The volume transition temperature decreased with increasing PEG concentration, and a completely unexpected swelling behavior...
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