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We investigated, via small angle X-ray scattering, depolarized light scattering, rheometry, and transmission electron microscopy, the phase behavior of the mixture of a symmetric polystyrene-block-poly(n-pentyl methacrylate) copolymer (PS-b-PnPMA) showing the closed-loop phase behavior and excellent baroplasticity, and dodecanol, a PnPMA-selective solvent. We found that the addition of a selective...
We report the preparation of highly charged nanocomposites comprised of water-soluble, anionic fullerene and cationic poly-phenylenevinylene (PPV) derivatives. The nanocomposites display high fluorescence quenching efficiency (99%) presumably due to enhanced miscibility between cationic PPV and anionic C 60 via electrostatic interactions. We show that complexation between the cationic PPV...
A supramolecular polymer gel formed between triptycene-based bis(crown ether) and copolymer containing dibenzylammonium (DBA) moieties by host–guest interactions was described. We demonstrated the formation of the supramolecular polymer networks between the bis(crown ether) and the copolymer by the 1 H NMR spectroscopy and solution viscometry, and we also obtained a colorless and transparent...
Bi-component fibers typically combine multiple functions that arise from at least two distinct components. As a result, these fibers can incorporate carbon nanotubes, which impart specific and controllable mechanical, electrical, and thermal transport properties to the fibers. Using gel spinning, sheath-core polyacrylonitrile–polyacrylonitrile/carbon nanotube bi-component fibers with a diameter of...
We demonstrate that without changing the filler content mechanical properties of commodity plastics with immiscible soft inclusions can be decisively enhanced, simply by pressure induced flow processing in the solid state. As an example, we have chosen acrylonitrile-butadiene-styrene (ABS), where shape and orientation of the soft fillers were changed by processing, resulting in an array of aligned...
The structure, porosity and crystallization behavior of poly (L-lactic acid) and poly (L-lactic acid)/polyurethane porous membranes, prepared from ethanol/dioxane and ethanol/water coagulation baths through immersion precipitation, have been systematically investigated. The diffusion rate between solvent and nonsolvent as well as the equilibrium phase diagram of PLLA/solvent/nonsolvent system were...
This study introduces a synthetic method to graft zwitterionic poly (2-methacryroyloxyethyl phosphoryl choline) brushes onto TiO 2 nanoparticles with thickness of a few nanometers. The grafting of zwitterionic polymer brushes was characterized by electron microscope measurements, zeta-potential analysis, and thermo-gravimetric analysis. The technique we employed to synthesize those hybrid...
This feature article presents a short review of the recent developments in the synthesis of conjugated polyelectrolytes (CPEs) along with their applications in organic optoelectronic devices with particular focus on the molecular structures of CPEs with ionic functionality, synthetic approaches, and their utilization as an interfacial layer. The orthogonal solubility of the CPEs allows the simple...
A series of novel amphiphilic, conjugated triblock copolymers of poly(9,9-didodecylfluorene-2,7-diyl) (PF) were synthesized. The rod-like PF midblock was synthesized via a Yamamoto-type reaction of 2,7-dibromo-9,9-di-n-dodecylfluorene, and endcapped with 4-bromobenzyl alcohol to obtain the hydroxyl end-functionalized PF (PFOH). A series of α-monocarboxy-ω-mono-methoxy poly(ethylene glycol)s with various...
Tensile properties of gel-spun polyacrylonitrile (PAN) and PAN/carbon nanotube (CNT) fibers were studied as a function of temperature from −100 °C to 300 °C at a constant strain rate of 0.01/s. Tensile strength and modulus values at low temperature were as high as 1.65 GPa and 44.4 GPa, respectively. The tensile strength and modulus of PAN fibers decreased with increasing temperature, while drawability...
The effects of wetting induced surface segregation on the crystal nucleation, growth rate, morphology and crystal orientation of melt-miscible crystalline–crystalline diblock copolymer of poly(l-lactide)-block-poly(ethylene glycol) (PLLA-b-PEG) thin films (∼90 nm) were investigated in this work with reflection optical microscopy (ROM), atomic force microscopy (AFM), and two-dimensional grazing incident...
Mesophase separation between the incompatible blocks in multiblock copolymers OBC (Olefin Block Copolymers), coupled with the macrophase separation in its blends with iPP (isotactic polypropylene), makes iPP/OBC a unique blend system to understand the interaction between multiple phase separations and the subsequent or simultaneous crystallization in multi-scales. The role played by OBC content as...
The endothermic heat just above glass transition for the drawn poly(lactic acid)s (PLAs) films with four different d-isomer contents (1, 4, 10, and 20 mol%: named as PLA1, PLA4, PLA10, and PLA20) was observed on differential scanning calorimetry (DSC) heating scan. The amount of endothermic heat increases with increasing the draw ratio, which means that the endotherm is undoubtedly caused by stretching...
Bisphenol-A polycarbonate (PC) and amorphous polyamide (aPA) were used as reactive system to study the interfacial interchange reaction between condensation polymers. Aminolysis is the main process during thermal annealing at 160–180 °C. The simultaneously scission of PC chains and formation of PC-aPA copolymer chains during the reaction process, can act as interfacial compatibilization agents between...
Morphological structure development of the in-situ polymerized isotactic polypropylene/graphene nanocomposites was investigated during the annealing process. The material was prepared via an in-situ slurry polymerization method with graphene-supported Ziegler–Natta catalyst. An interpenetrating network was observed at a relatively low graphene concentration after the sample was annealed for a long...
Controlling the hierarchical structure of melt-processed polymers is vital to “structuring” processing and tailoring properties of the product. In this work, polypropylene (PP)/octene-ethylene copolymer (POE) blends were injection-molded using so-called dynamic packing injection technique, which imposed oscillatory shear on the gradually cooled melt during the packing solidification stage. In this...
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)...
Based on a spirocyclic tetraether derived from pentaerythritol and [1,1′-binaphthalene]-2,2′-diol, three porous organic polymers (SPOP-7∼9) were prepared through Suzuki reaction, Sonogashira–Hagihara reaction, and thiophene-based oxidative coupling polymerization, respectively. According to the obtained nitrogen physisorption isotherms, these polymers show permanent microporous nature with the Brunauer–Emmett–Teller...
The growth of transcrystallites induced by fracture stress was studied in the solution casted polystyrene (PS)/poly(ethylene oxide) (PEO) blends films. Both the structure geometry of the crack edge and the effect of local fracture stress on the crystallization were considered. It was found that the local fracture stress contribution is the most important factor to the formation of transcrystallites...
The crystalline/crystalline polymer blend of poly(butylenes succinate)/poly(ethylene oxide) (PBS/PEO) exhibited lower critical solution temperature (LCST) phase separation behavior at temperatures above the melting point of PBS, which was measured by phase contrast optical microscopy (PCOM) technique. In this work, we determined the LCST phase diagram of PBS/PEO blends, and then investigated the effect...
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