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The molecular design concept of silicon-nitrogen synergistic effect for highly-efficient flame retardants has been demonstrated in the preparation of reactive type flame retardants which exhibits high flame retardation efficiency and property enhancement ability for developments of high performance polymers. In the synthetic route, a benzoxazine-containing triethoxysilane compound is obtained and...
A fluorinated acrylate monomer simultaneously containing one hydrophilic hydroxyl and one hydrophobic perfluoroalkyl group was synthesized, which was then utilized to copolymerize with isobornyl methacrylate and butyl acrylate to prepare core–shell-structured latex nanoparticles through two-step emulsion polymerization. In this synthesis process, no any organic solvents or fluorine-containing surfactants...
We report the rheological properties of a new azobenzene side chain liquid crystal polymer (SCLCP) with photo-responsive behavior in the range of 0 °C to 50 °C as probed by small amplitude oscillatory shear (SAOS) rheometry with in situ UV irradiation. In the linear viscoelastic (LVE) strain regime, temperature sweeps measured G′ and G″ from 80 °C to −5 °C and identified glass transition temperatures...
We review recent work on the adsorption of proteins on two types of well-defined colloidal particles, namely on i) spherical polyelectrolytes that consist of a solid core onto which long chains of a polyelectrolyte are attached, and ii) core–shell microgels that have a shell of crosslinked poly(N-isopropylacrylamide) (pNiPAm) chains. The latter system may bear charges as well by copolymerization with...
New functional crosslinked poly(ethylene glycol) (PEG) micrometer-sized particles of narrow size distribution were prepared by dispersion co-polymerization in an aqueous continuous phase of the monomers methacrylate polyethylene glycol carboxylic acid (MA-PEG-COOH) or methacrylate polyethylene glycol amine (MA-PEG-NH 2 ) with polyethylene glycol methacrylate ether (MA-PEG-OCH 3 ) and...
Novel functionalized ketones (K_PY) incorporating one/two pyrene moieties or a pyridinium chromophore for radical and/or cationic polymerization under soft irradiation conditions (Xe–Hg lamp, halogen lamp) are proposed. These compounds exhibit red-shifted absorptions and enhanced molar extinction coefficients (e.g. for near visible lights (395 nm), the absorption can be increased by a factor of 20)...
An alkylated skeleton of indeno[2,1-c]fluorene, viewed as a positional isomerism of indeno[1,2-b]fluorene, was developed to construct several conjugated oligomers and polymers through a Pd-catalyzed Suzuki coupling reaction for organic light-emitting diodes. Single crystal analysis indicated that the structure of indeno[2,1-c]fluorene was twisted due to close H---H contacts in the crowded region of...
In this work, two different polyhedral oligomeric silsesquioxanes (POSS)—octaisobutyl-POSS (OIBS) and allylisobutyl-POSS (AIBS)—were incorporated into poly(methylvinylsiloxane) (VMQ) by melt mixing and then the corresponding blends were chemically crosslinked by peroxide. NMR analysis revealed that AIBS molecules containing double bonds were successfully grafted onto VMQ macromolecular chains during...
Stereoselective polymerization of 1,3-pentadiene (1,3-PD) by using the ternary catalyst system neodymium versatate (Nd(vers) 3 )/alkylaluminium/Al(i-Bu) 2 Cl was examined. Both homogeneous and heterogeneous catalyst systems prepared in the presence or absence of 1,3-PD monomer during catalyst preparation were employed for 1,3-PD polymerization. The effects of the type of alkylaluminium,...
An epoxy monomer of 4,4′-diglycidyloxybiphenyl (BP) was synthesized and cured with a tetra-functional amine, sulfanilamide (SAA), to produce novel liquid crystalline epoxy resins (LCERs). The thermal properties, liquid crystalline morphologies, and cure behavior of the monomer were studied using differential scanning calorimetry, wide angle X-ray diffraction, and polarized optical microscopy. The...
In the present work, a poly(ε-caprolactone)-b-poly(ethylene oxide) (PCL-b-PEO) block copolymer was doped with LiClO 4 at various salt concentrations. The morphology of the hybrids was characterized with time-resolved small-angle X-ray scattering (SAXS). It is observed that LiClO 4 can induce microphase separation of the miscible PCL-b-PEO in the melt. With increase in doping ratio,...
Robust oil- and water-repellent or amphiphobic particulate coatings were prepared from epoxy glue and bi-functional silica particles bearing poly(2-perfluorooctylethyl methacrylate) (PFOEMA) and poly(acrylic acid) (PAA) coronal chains. To prepare the particles, silica was first co-grafted in a one-pot process by poly[3-(triisopropyloxysilyl)propyl methacrylate]-block-poly(2-perfluorooctylethyl methacrylate)...
This work presents a procedure for functionalization of graphene sheets from edges by polyglycerol. Hyperbranched polyglycerol with a bi-dentate aromatic segment in its focal point was synthesized and used to sandwich graphene sheets from the cut-edges. Due to the hydrophobicity of the flat surface of the edge-functionalized graphenes and hydrophilicity of their edges, they changed their conformation...
The effect of crystal morphology, such as the crystallinity and lamellar structure, on the radiation-induced graft polymerization of styrenesulfonate ethyl ester (E4S) onto poly(ether ether ketone) PEEK films was evaluated. The PEEK films possessing crystallinities ranging from 11 to 32% were irradiated with 30–150 kGy, and the graft polymerization was performed in an E4S/1,4-dioxane solution at 80 °C...
The effect of mechanical constraints on the anti-polyelectrolyte behavior of zwitterionic polymers was studied systematically in this work via viscosity examination of uncross-linked polymer solutions, swelling of cross-linked polymer gels and swelling of elastomers compounded with these gels. Zwitterionic polymers, poly(sulfobetaine methacrylate) (polySBMA), poly(2-methacryloyloxyethyl phosphorylcholine)...
In-chain multi-functionalized polystyrene possessing definite geminal dimethylamino groups along the polymer backbone, poly(styrene-co-1,1-bis(4-dimethylaminophenyl)ethylene) (poly(styrene-co-BDADPE)), has been designed and synthesized via living anionic copolymerization of styrene with 1,1-bis(4-dimethylanimophenyl)ethylene in benzene at 50 °C, using sec-butyllithium as initiator. The amine functionality...
Fiber formation from highly stretched melt and mechanical deformation of the fiber are investigated by molecular dynamics simulations. Polyethylene molecules of moderate chain length comprising 513 united atoms are simulated under constant temperature and stress (NTτ) conditions. Rapid crystallization into fiber structures of alternating crystalline amorphous layers is observed, where emergence of...
Macroscopically aligned isotactic polypropylene (iPP) fibers with different diameters ranging from 0.7 to 13.2 μm were successfully fabricated by high-temperature solution electrospinning using an infrared (IR) heating system. Polarized optical microscope (POM), scanning electron microscope (SEM), wide-angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC) and polarized Fourier transform...
A hybrid of reduced graphene nanoribbon (GNR)–carbon nanotube (CNT) (i.e. R-GNR/CNT hybrid) with unique three-dimensional (3D) nanostructures has been prepared via a facile unzipping and reducing method. Interlocked structures are formed within the nanohybrids where one-dimensional (1D) CNTs act as bridges connecting individual two-dimensional (2D) GNRs, which not only prevent the aggregation of GNRs...
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