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Five series of binary copolymers, poly[2,5-di(ROOC)styrene-co-2,5-di(R′OOC)styrene]s (R=n-C 3 H 7 –, R′=C 2 H 5 –, n-C 4 H 9 –, and n-C 5 H 11 –; R=n-C 6 H 13 –, R′=n-C 4 H 9 –, and n-C 5 H 11 –), were synthesized via free radical polymerization. The random nature of the copolymers was expected...
The study investigated shape memory properties of nanoclay-tethered polyurethane nanocomposites. Polyurethanes based on polycaprolactone (PCL) diol, methylene diisocyanate, and butane diol and their nanocomposites of reactive nanoclay were prepared by bulk polymerization in an internal mixer and the values of shape fixity and shape recovery stress were determined as function of clay content. The melting...
Novel chelating polyfluorene polyelectrolytes and their corresponding neutral precursors with Ir complex incorporated into polymer backbone were synthesized by Suzuki polycondensation reaction. The aminoalkyl or quaternized ammonium group provides good solubility of these phosphorescent polymers in alcohols which has a great advantage in fabrication of multi-layer polymer phosphorescent PLEDs. The...
Two series of copolyimides were designed and synthesized by one-step polycondensation of two diamines, 3,6-diaminoacridine (Acridine) and 4,4′-(9H-fluoren-9-ylidene)bisphenylamine (FBPA), with a dianhydride 4,4′-(hexafluoroisopropylidene)diphthalic anhydride (6FDA) or 3,3′,4,4′-benzophenonetetracarboxylic dianhydride (BTDA), respectively. The copolyimides were named as AFFx (Acridine-FBPA-6FDA polyimide)...
A series of hyperbranched triazine-containing polyfluorenes were synthesized by an “A 2 +A′ 2 +B 3 ” approach based on Suzuki polycodensation. The polymers showed pure blue emission and the maximum emissions red-shifted in polar solvents and in solid film. By introducing triazine into polyfluorene, the electron injection and transport properties were improved and green emission...
Polyfluorenes with 2-(2′-pyridyl)-benzimidazole (P1, P2 and P4) and 5-methyl-3-(pyridin-2-yl)-1,2,4-triazole (P3) groups in the side chain were synthesized by Suzuki polycondensation. The responsive properties of polymers on metal ions and H + were investigated by absorption and emission spectra. The fluorescences of polymers (P1–P4) were completely quenched upon the transition metal ions...
A novel method of surface modification by grafting hydrophilic poly(ethylene glycol) (PEG) chains onto the surface of a thin-film composite (TFC) polyamide reverse osmosis (RO) membrane was performed. Aminopolyethylene glycol monomethylether (MPEG-NH 2 ) was used as grafting monomer. The membranes were characterized by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR),...
The evaluation of microstructure and crystal morphology in injected-molded bar becomes much complicated because of the existence of a shear gradient and a temperature gradient from the skin to the core of the samples. To understand the relationship between shear rate-molecular weight and oriented structure of injection molded bar, in this work, the hierarchy structure and the effect of molecular weight...
In the present study, we successfully prepared non-woven mats from stable regenerated silk fibroin aqueous solution at high concentration. Scanning electronic microscope (SEM) was used to observe the morphology of the fibers. The structure of the fibers was characterized using Fourier transform infrared (FTIR), wide-angle X-ray diffraction (WAXD) and differential scanning calorimetry (DSC). The mechanical...
The typical process used to synthesize water expandable polystyrene (WEPS) was modified and applied to prepare water expandable polystyrene (PS)–clay nanocomposites (WEPSCN). The natural clay can be uniformly dispersed in water due to its hydrophilicity. It can be further carried into the styrene monomer by the formation of water-in-oil inverse emulsion. Via suspension polymerization, spherical PS...
Herein we report a new and simple method that has been developed to prepare smart polymeric microgels consisting of temperature-sensitive cores with pH-sensitive shells. The microgels were obtained directly from one step seed polymerization of N-isopropylacrylamide and N,N-methylenebisacrylamide from water-soluble biopolymers containing carboxymethyl groups in supercritical carbon dioxide. The effect...
Tenascin, an important extracellular matrix protein, is subject to stretching force under physiological conditions and plays important roles in regulating the cell–matrix interactions. Using the recently developed single molecule force–ramp spectroscopy, we investigated the unfolding–folding kinetics of a recombinant tenascin fragment TNfnALL. Our results showed that all the 15 FnIII domains in TNfnALL...
This paper investigates the enthalpy of solid phase transition of isotactic polypropylene from the mesomorphic phase to the monoclinic crystal form using DSC. iPP fibres with either monoclinic crystal form or mesomorphic phase were obtained by varying the conditions of melt spinning. XRD and mechanical tests were used to confirm the crystal forms. It is found that conventional DSC techniques fail...
A strategy based on heat-deformable monolayer polymer (polystyrene) colloidal template and precursor solution-dipping is presented to fabricate large-scale nanopillar arrays. In the method, the appropriate heating time of the polymer colloidal templates is a key factor. Fe 2 O 3 and silica hexagonal periodic triangular prism nanopillar arrays with an aspect ratio of about 1.5:1 were...
Two new soluble arylenevinylene-based polymers comprising of an electron-donating carbazole unit and an electron-accepting 2,1,3-benzothiadiazole (or fluorenone) unit in the main chain were synthesized by Heck polycondensation between 3,6-divinylene-9-decyl carbazole and 4,7-dibromo-2,1,3-benzothiadiazole (or 2,7-dibromofluorenone). In the toluene solution, a polymer with benzothiadiazole unit showed...
A new anionic water-soluble polyfluorene—poly(9,9-bis(4′-sulfonatobutyl)fluorene-co-alt-1,4-phenylene) sodium salt (PFS) was synthesized by Suzuki-coupling reaction. The anionic polyfluorene shows bright blue photoluminescence and it was found the photoluminescence could be highly quenched by a bioactive dye (Lucifer yellow cadaverine biotin-X dipotassium salt). PFS photoluminescence quenching only...
Novel dendrimer derivatives combining the temperature- and pH-sensitivities are synthesized. At first, polyamidoamine (PAMAM) dendrimers with generations 1–5 are synthesized by the reaction of ethylenediamine with methyl acrylate, and then the dendrimers are acylated by chloroacetyl chloride to obtain PAMAM-Cl, which can act as a macroinitiator for further synthesizing functional dendrimers. For fulfilling...
A novel series of soluble conjugated random and alternating copolymers derived from 9,9-dioctylfluorene (FO) and 1,1-dimethyl-2,3,4,5-tetraphenylsilole (PSP) were synthesized by Suzuki coupling reactions. The feed ratios of FO to PSP were 95:5, 90:10, 85:15, 70:30, and 50:50. Chemical structures and optoelectronic properties of the copolymers were characterized by elemental analysis, NMR, UV absorption,...
This paper presents a series of dendrimers via a convergent synthetic approach with three generations, which contain perylene diimide cores, Fréchet-type poly(aryl ether) dendrons, and carbazole (CZ) or oxadiazole (OXZ) peripheral functional groups. The higher generation dendrimer has an obvious site-isolation or dilution effect of dendrons, which results in a relatively small red-shift of absorption...
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