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Polyurethanes grafted with well-defined polar pendants were synthesized and investigated. A series of linear and dendritic poly(urea/malonamide)s with uniform chain length were first prepared from an iterative synthesis route, which is based on a dual-functional building block, 4-isocyanate-4´-(3,3-dimethyl-2,4-dioxo-azetidine)diphenyl methane (IDD). Moreover, side chain polyurethanes (SPUs) bearing...
The elastic properties of a fully aromatic polyimide were measured for the first time by Brillouin scattering in a high-pressure diamond anvil cell. Its isothermal compressibility and pressure dependence of mechanical moduli (Ks, E, and G) were studied and determined up to 6.4 GPa. Further, piezochromic behavior of the polyimide film was observed and studied in detail by spectroscopic analysis. Pressure-induced...
Porphyrin-[60]fullerene polymers linked by metal axial coordination of fullerenoacetic diacids e-isomer with dihydroxo Sn(IV) porphyrin have been prepared and characterized. The polymers display the regular one-dimensional linear arrays with lengths exceeded 200 nm and show good thermal stability. The efficient photoinduced electron transfer from singlet excited porphyrin to fullerene in the polymer...
Sequential thiol-ene click reaction is reported for amphiphilic glycosylated polyphosphazene. Poly[bis(allylamino)phosphazene] was used as precursor to go through UV irradiation with 2,3,4,6-tetra-O-acetyl-1-thiol-β-D-glucopyranose (SH-GlcAc 4 ) and 1-dodecanethiol in sequence. Variation of the reaction conditions, including click reaction time and the dose of photoinitiator, led to different...
In this work, the relationship between properties and morphologies of PA6/EPDM-g-MA/HDPE ternary blends was studied. Two processing methods (one- and two-step methods) were applied to prepare the PA6/EPDM-g-MA/HDPE ternary blends. The dependence of the phase morphology on interfacial interaction and processing method was discussed here. It was found that core-shell morphology (core: HDPE, shell: EPDM-g-MA...
Chiral poly(glycerol methacrylate)s (PGMAs) are synthesized via ATRP using enantiopure solketal methacrylates followed by acidic hydrolysis. The optical activity of the polymers is confirmed by measurements of the circular dichroism. Furthermore, the chirality of the PGMAs containing repeat units with diol groups is determined via 1 H NMR spectroscopy employing a three-component chiral derivatizing...
A semi-continuous process using scCO 2 is reported for processing polymer–clay composites with high clay loading (i.e. 10wt %) by reducing the collapse of the exfoliated clays. Two major modifications are involved in the new procedure: exfoliating the nano-clay directly into the hopper filed with pellets followed by processing the composite immediately and sequentially mixing the clay into...
Syndiotactic polystyrene (sPS) composites filled with well-dispersed carbon nanocapsules (CNC) were prepared through solution blending along with ultrasonication. Several analytic techniques, including DSC, FTIR, PLM, WAXD, TEM, and TGA were performed to reveal the CNC effects on the crystallization, morphology and the thermal degradation of the as-prepared sPS/CNC composites. Addition of CNC was...
The double melting behavior of syndiotactic polystyrene (sPS) with β′-form crystallites was systematically investigated by several analytical techniques, including differential scanning calorimetry (DSC), polarized light microscopy (PLM), transmission electron microscopy (TEM), as well as wide-angle and small-angle X-ray scattering (WAXD, SAXS). For preventing the possible chain re-organization during...
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...
Crystal growth rates of syndiotactic polystyrene (sPS) and its blends with atactic polystyrene (aPS) at various temperatures (T c ) were measured using a polarized optical microscope (POM). In addition to the positively birefringent spherulites and axilites (P-spherulites and P-axilites) which are predominantly observed, small population of negatively birefringent spherulites (N-spherulites)...
A series of polymer-clay nanocomposite (PCN) materials that consisted of emeraldine base of poly(o-ethoxyaniline) (PEA) and layered montmorillonite (MMT) clay were prepared by effectively dispersing the inorganic MMT clay platelets in organic PEA matrix via in situ oxidative polymerization. Organic o-ethoxyaniline monomers were first intercalated into the interlayer regions of organophilic clay hosts...
Isothermal crystallization kinetics of poly(ethylene terephthalate) (PET) in its blends with poly(ether imide) (PEI) has been investigated by differential scanning calorimetry (d.s.c.). A modified Avrami analysis considering both primary and secondary crystallization was employed to extract the kinetic behaviour of these two crystallization stages. The crystallization rate constants at various crystallization...
The phase behaviour of amorphous and semicrystalline poly(butylene terephthalate) (PBT)/poly(ether imide) (PEI) blends has been investigated. PBT and PEI were miscible in the melt over the entire composition range. Upon the crystallization of PBT at temperatures lower than 210°C, a strong segregation of PEI was observed. The morphological observation by optical microscopy indicated that PBT crystallization...
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