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Poly(l-lactide-co-succinic anhydride) networks were synthesised via the carbodiimide-mediated coupling of poly(l-lactide) (PLLA) star polymers. When 4-(dimethylamino)pyridine (DMAP) alone was used as the catalyst, gelation did not occur. However, when 4-(dimethylamino)pyridinium p-toluenesulfonate (DPTS), the salt of DMAP and p-toluenesulfonic acid (PTSA), was the catalyst, the networks obtained had...
We report on the characterization of the solution structure of poly(N-vinyl-2-pyrrolidone)s (PVP) by small-angle X-ray scattering (SAXS) and by online coupling of asymmetrical flow field-flow fractionation (A4F), SAXS and dynamic light scattering (DLS). The commercial products PVP K30 and PVP K90 with nominal molar masses of 40 × 10 3 and 360 × 10 3 g mol −1 , respectively,...
pH-sensitive nanoparticles were prepared from a novel amphiphilic copolymer poly(2-phenyl-1, 3-dioxan-5-yl methacrylate-co-2-hydroxyethyl acrylate), poly(PDM-co-HEA), which was synthesized from the pH-sensitive hydrophobic monomer 2-phenyl-1, 3-dioxan-5-yl methacrylate (PDM) and the hydrophilic monomer 2-hydroxyethyl acrylate (HEA) with unit ratio (4:6) via radical polymerization. The random amphiphilic...
The development of a conducting composite from its one-step synthesis in aqueous dispersed medium to the characterization of its chemical sensor performance is detailed. Composite films of polyaniline and polyacrylate were processed from the crude dispersion with no need for post-formulation. The synthesis has been optimized to be as simple, cheap and transferable as possible. The composite composition...
The orientation of lamellar crystals in non-banded spherulites of it-polystyrene and it-poly(butene-1) was investigated by microbeam X-ray diffraction. The two-dimensional intensity map of diffraction enables us to examine the local orientation of lamellar crystallites in the non-banded spherulites. The obtained results indicated the re-orientation of crystallites in non-banded spherulites and confirmed...
To prepare epoxy materials with improved thermal remendability, two types of epoxy resins (N,N-diglycidyl-furfurylamine (DGFA) and furfuryl glycidyl ether (FGE)), which were synthesized in the authors' lab and contained different proportions of furan and epoxide groups, were blended and cured by anhydride and maleimide. Like the cured version of either DGFA or FGE alone, the cured blends of DGFA and...
It is widely thought that confinement of an amorphous polymer alters the chain mobility, which affects the temperature and intensity of the glass transition. The present study sought to determine whether the same effects extend to semicrystalline polymers. Confinement was achieved by forced assembly of hundreds of alternating layers of poly(ethylene oxide) (PEO) with either poly(ethylene-co-acrylic...
Poly(ethylene terephthalate) (PET) nanosheets were fabricated by winding nanofibers onto a spool. The nanofibers were prepared by irradiating PET fibers with radiation from a carbon dioxide laser while drawing them at supersonic velocities. A supersonic jet was generated by blowing air into a vacuum chamber through the fiber injection orifice. A new vacuum chamber was developed to produce nanosheets;...
Polyethylenimine (PEI) with enhanced fluorescence and thermal sensitivity was achieved by Michael addition of divinylsulfone (DVS) and N-isopropylacrylamide (NIPAm) respectively. The fluorescence enhancement is quantitatively studied by tailoring the amount of DVS, the medium pH, the substituting acrylates, the substrate polymers with different type amine groups, and the substrate molecular weights...
Poly(oligo(ethylene glycol) methacrylate) (POEGMA)-block-poly(2-(methacryloyloxy) ethyl trimethylammonium chloride) (PMETAC) brushes were synthesized on silicon wafer surfaces by a surface-initiated atom transfer radical polymerization (ATRP) method. Salt-triggered collapse of the polyelectrolyte in solution was employed to induce phase segregations between the two hydrophilic blocks and thus to develop...
A three diamensional (3D) bicontinuous skeleton macroporous monolith was firstly prepared by in situ atom transfer radical polymerization (ATRP) of ethylene glycol dimethacrylate (EDMA) at the room temperature. The structure of the monolith could be mediated by the different ratio of EDMA to initiator and the 3D bicontinuous skeleton structure was obtained at the ratio of 70:1. Compared with the traditional...
In this study, imine bond coupled pyrrole–carbazole–pyrrole monomers were synthesized in four steps and then directly polymerized onto ITO/glass surface via potentiodynamic electrochemical process. Electrochemical and optical bad gap of these monomers and polymers were calculated by using cyclic voltammetry and UV–Vis absorption spectroscopy. Conductivity of the polymers with different alkyl side-chain...
A series of novel soluble conjugated copolymers consisting of electron-accepting 2-pyran-4-ylidenemalononitrile (PM) and electron-donating fluorene connected by different electron-donating ability conjugated moieties were synthesized by Suzuki coupling polymerization. The structures of the copolymers were characterized and their physical properties were investigated. High molecular weight (M n...
The nanolayered structure of a forced-assembly of two immiscible amorphous polymers, prepared by layer-multiplying coextrusion, is analyzed for the first time by means of USAXS. The experimental long spacings for the series of PMMA/PS films studied show a good correlation with the nominal periodicity values of the stacks. In addition, the long spacings, derived from a localized area in AFM, are also...
A series of hexafluoroisopropylidene bisphenol poly(arylene ether sulfone) (BAF PAES) segmented block copolymers with varying fractions of polydimethylsiloxane (PDMS) were synthesized by a condensation reaction of hydroxyl-terminated BAF PAES and dimethylamino endcapped PDMS. The segmented block copolymers have high thermal stability. The BAF PAES homopolymer exhibits a tensile modulus of 1700MPa...
In our previous study, a computer simulation scheme based on Doi–Onuki theory is proposed to simulate the dynamics of the shear-induced phase separation in semi-dilute polymer solutions [KOBUNSHI RONBUNSHU 2007, 64, 324]. The scheme employs Ianniruberto–Marrucci model as a constitutive equation to express the viscoelastic behavior of the solution explicitly. The scheme enables us to simulate the time-evolution...
Silica nanoparticles having specific surface area (SSA) 50–300 m 2 g −1 were admixed into vinyl-terminated dimethylsiloxy monomer with a dual asymmetric centrifuge (planetary mixer) and cured to form PDMS-based nanocomposites containing up to 12 vol% SiO 2 . Thin sections of cured nanocomposites obtained by a cryostate-microtome were analyzed by TEM while small and ultra small...
In this study, soy protein concentrate (SPC) was blended as plastic with poly(butylene adipate-co-terephthalate) (PBAT). An extra amount of water was added to SPC prior to compounding to ensure that SPC behaved like a plastic during mixing. Because of the extensive crosslinking and agglomeration during compounding and the fact that most water was evaporated after drying the compounds, the SPC phase...
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