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A series of copolyesters containing ionic groups (PETIs-K) were synthesized by melt co-polycondensation using terephthalic acid, ethylene glycol, and potassium salt of bishydroxyethyl ester of 10-hydroxy-10-oxo-10H-phenoxaphosphine-2,8-dicarboxylic acid (DHPPO-K) as monomers. The copolyesters only with analogous phosphorus-containing heterocycles (PETPs) were also synthesized and used as a control...
The effect of the temperature on strain induced crystallization (SIC) of natural rubber (NR) is studied by in situ wide angle X-rays scattering (WAXS) experiments performed along different thermo-mechanical paths (cyclic deformation at different temperatures or crystallization and melting in the deformed state). The crystallinity index (CI), the average crystallite size (L200) and the average volume...
The thermo-mechanical characteristics of thermoset epoxy based nanocomposites are investigated with molecular dynamics (MD) simulations. For establishing molecular models, spherical silica (SiO2) nanoparticles and crosslinked epoxy structures (EPON 862®-TETA) are considered as a filler and matrix phase material, respectively. The reinforcing effect of stiffness and thermal stability by addressing...
A variety of cross-linkable block copolymers were studied to prepare cross-linked structure and nanoobjects which are stable in solvents; at the same time, some degradable core cross-linked star polymers and gels which can be degraded under catalysis were also reported. In this study, degradable chemical cross-linked poly(tert-butyl acrylate) gels were prepared with phenolic ester linkage, which can...
This work, based on structure/properties relationships of associating polymers, aims to investigate the role of topology in the self-assembling behavior of responsive graft copolymers. For that purpose, two graft copolymers with inverse topologies were prepared with similar amounts of water-soluble chains (poly(N,N-dimethylacrylamide) = PDMA) and LCST polymer chains (poly(N-isopropylacrylamide) = PNIPA)...
We describe here the design and synthesis of the conjugated polymers containing dye-modified cardo fluorenes for the dual emissions. Mono and di-substituted cardo fluorenes with boron dipyrromethene (BODIPY) were introduced into alternating conjugated polymers using bis-thienyl-benzothiadiazole as a comonomer for constructing the donor (D)-acceptor (A) pairs through the main-chains. The polymeric...
The superstructures developed in the welds between injection molded plates made from α-nucleated and non-nucleated isotactic polypropylene (iPP) were analyzed by infrared (IR) microscopy, polarized light microscopy (PLM) and differential scanning calorimetry (DSC). Layers of distinct structures and size formed during welding in the welds were identified by PLM. Deformation of spherulites occurred...
Redispersible polystyrene (PS) latexes were prepared through surfactant-free emulsion polymerization (SFEP), employing only 0.54 mol% (with respect to styrene) of the monomer 2-dimethylaminoethyl methacrylate hydrochloride (DMAEMAH+Cl−) and 0.25 mol% of the initiator 2,2′-azobis[2-(2-imidazolin-2-yl)propane]dihydrochloride (VA-044) as positively charged stabilizing moieties. The polymer particles...
Several polymers are constructed through a facile one-pot approach connecting glycoluril with different aldehydes using p-toluenesulfonic acid as both catalyst and solvent in a sealed tube at high temperature. Fourier transform infrared and solid-state 13C CP/MAS NMR spectroscopy are used to elucidate the final structure of the glycoluril based porous organic polymers. The materials, with Brunauer–Emmet–Teller...
Soybean oil (SO) was modified through the reaction with dicyclopentadiene (DCPD) to convert carbon double bonds in the soybean oil molecules into norbornyl groups of different ratios. Styrene-butadiene rubber (SBR) compounds with carbon black (CB) containing different extender oils including SO, modified SO (MSO) and naphthenic oil (NO) were prepared for comparison. The gel fraction, crosslink density,...
Electrochemically mediated atom transfer radical polymerization (eATRP) of acrylamide was investigated in aqueous media. The synthesis of poly(ethylene oxide)-block-poly(acrylamide) block copolymers via eATRP under potentiostatic conditions was carried out. Various polymerization parameters were examined, including temperature, monomer concentration, ligand structure, and degree of polymerization...
Natural polysaccharide chitin nanofibers, prepared with a series of chemical and mechanical treatments, were used as an absorbent material for arsenic (As(III)) removal. The dimensions of chitin nanofibers, determined by small-angle X-ray scattering (SAXS), were about 6 nm in thickness, 24 nm in width and a few hundred nanometers in length. The chemical/mechanical treatment enabled the chitin nanofiber...
This study aims to explore the origin of toughness in β-phase isotactic polypropylene (i-PP). Samples of commercial-grade i-PP, both neat and nucleated with a specific β-nucleating agent (N,N′-dicyclohexylnaphthalene-2,6-dicarboxamide), were subjected to a combination of structure-sensitive methods and fracture mechanical testing. In addition to common structural characterisation methods, solid-state...
Long and broad poly(ethylene terephthalate) (PET) nanofiber sheets were fabricated by irradiation of PET fibers with a CO2 laser while drawing at supersonic velocities and continuously winding the nanofiber sheet onto a net conveyor operated at constant speed. A supersonic jet was generated by blowing air into a vacuum chamber through the fiber injection orifice. A new apparatus was developed to continuously...
The phase transitions in the films of an asymmetric polystyrene-b-poly(2-vinylpyridine) (PS-b-P2VP) were investigated by grazing incidence small-angle X-ray scattering (GISAXS) and transmission electron microscopy (TEM). Compared with the sequential transitions in the bulk, hexagonally perforated layer (HPL) – gyroid (GYR) – disorder (DIS) upon heating, the transitions in film geometry were dramatically...
One necessary point towards achieving the enhanced mechanical properties in the nanocomposite systems, comprising a polymeric matrix and the graphene sheets (GSs) as the reinforcement, is the number of GSs layers regarding its relation with the gyration radius of the matrix. In this study, a stable suspension containing the surfactant wrapped graphene sheets (SWGSs) was successfully synthesized via...
Cold crystallization of electrospun fibers from poly (l-lactide)/poly (d-lactide) = 5/5 blends results in profuse stereocomplex crystals with little trace of homocrystals. In contrast, homocrystals prevail in the solution cast and melt-quenched films with same composition upon cold crystallization. With aid of FTIR technique it is confirmed that intermolecular ordering between poly (l-lactide) and...
The influence of propargyl groups on the thermal polymerization of phthalonitrile groups has been examined through reaction of a blend of a bisphthalonitrile viz. 2,2-bis(4-phthalonitrile oxy phenyl)propane and a bispropargyl ether viz. 2,2-bis(4-proparyloxy phenyl)propane (BPhPR). The possibilities for co-reaction of the propargyl and phthalonitrile moieties and/or the catalytic nature of the cure...
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