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In the present work, the recently developed thermal fractionation technique successive self-nucleation and annealing (SSA) was applied to blends of branched and linear polyethylenes (PEs), as a method to evaluate the phenomena of miscibility and segregation in PE blends. The melting behavior of the systems, after a controlled cooling and after the application of SSA was compared.The DSC scans corresponding...
Binary blend membranes of poly(4-vinylpyridine) (PVP) with ethylcellulose (EC) have been prepared by a solution casting technique with chloroform as solvent. The membranes appear macroscopically miscible but microscopically immiscible based on wide-angle X-ray diffraction, differential scanning calorimetry and scanning electron microscope investigations. Permeating feature of five pure gases through...
The number of applications employing polymeric optical materials is growing rapidly due to recent advances in telecommunications, display, and laser markets. For a number of these applications, organic dyes (chromophores) are added to the polymer host to add linear or nonlinear optical properties to the system. In homogeneous systems, dye diffusion is not an issue; however in multiple stacks of polymer...
Novel inorganic/organic composites were constructed from highly conductive Li2S–SiS2–Li4SiO4 oxysulfide glass and linear poly(oxyethylene)s (POEs) or high molecular weight branched POE without adding any lithium salts. The ionic conductivity of composites was lower than that of the oxysulfide glass, but the mixing of glass powder into the POEs allowed the preparation of thin films. The composites...
In order to clarify the photo-induced solid-state reactions of a series of dialkyl Z,Z-muconates, the time-resolved FT–IR measurements were performed. From the observations of the IR spectral changes in these reactions, the following three types of reactions were found: (1) the polymerization reaction to give the stereoregular polymer; (2) the isomerization reaction from Z,Z to E,E-form followed by...
Off-line small- and wide-angle X-ray scattering and optical birefringence measurements on partially oriented yarns (POY) of poly(trimethylene terephthalate) prepared at different take-up speeds suggest the formation of a rigid amorphous phase for intermediate take-up speed POY. Simultaneous synchrotron small-angle X-ray scattering (SAXS) and wide-angle X-ray diffraction (WAXD) techniques were utilized...
The influence of β crystals on the mechanical properties of isotactic polypropylene is studied on compression-moulded sheets without filler or filled with stearate-coated calcium carbonate particles. A crystallisation procedure is setup for producing sheets with various amounts of β crystals, trying to keep constant crystallinity, spherulite size and crystal thickness. An optimum of β crystals among...
We investigated the structure of poly(allylamine hydrochloride) (PAAMHCl) gel-sodium dodecylbenzenesulfonate (SDBS) surfactant complexes using small-angle X-ray scattering. PAAMHCl gels were prepared by using N,N′-methylenebisacrylamide as a cross-linking agent. These gels were complexed with SDBS below a critical micelle concentration of the surfactant. The gel–surfactant complexes (GSC) exhibited...
Hybrid materials based on poly(n-butyl methacrylate-co-(3-(methacryloxypropyl)) trimethoxysilane) were synthesized via a sol–gel process. From a phase behavior study of these hybrid materials using a differential scanning calorimeter (DSC) and solid-state nuclear magnetic resonance (NMR) spectroscopy, it was found that the hybrid system was miscible for organic and inorganic phases with low silane...
Poly(trimethlene teraphthalate) (PTT) is one of the terephthalic polyester family members which can crystallize between its glass transition and melting temperatures. The crystal structure has been determined using both electron diffraction (ED) on single crystals and wide angle X-ray diffraction on powder and oriented fibers. The unit cell is triclinic with dimensions of a=0.46 (3)nm, b=0.61(2)nm,c=1...
Functionalized poly(ethylene oxide) (PEO) macromonomers (α-tertiary amino and ω-methacryloyl groups) were prepared by ring-opening polymerization of living PEO anions using 2-[2-(N,N-dimethylamino)-ethoxy]ethanol potassium alkoxides as an initiator with glycidyl methacrylate. Terminal double bond functionality was controlled in the range of 1–1.5 per molecule in toluene as the hydrocarbon solvent...
Equilibrium sorption of n-butane and acetaldehyde in melt-processed poly(ethylene terephthalate) (PET) microtomed flakes is reported. The n-butane sorption isotherm at 35°C is well described by the dual-mode model with the following parameters: kD=0.017cm3 (STP)/(cm3 amorphous polymer cmHg), C′H=1.3cm3 (STP) (cm3 amorphous polymer) and b=0.029cmHg−1. Acetaldehyde isotherms at 35 and 45°C may be described...
The Mark–Houwink equations relating the intrinsic viscosity of poly(trimethylene terephthalate) to its number and weight average molecular weights in two solvents are reported. Several simplified equations for single-point measurements are evaluated. The limit and accuracy of applicable equations are discussed.
An experimental study on the cellular structure and polymer morphology of a collection of polyethylene foams produced by a nitrogen solution process is presented in this work. Scanning electron microscopy (SEM) was used to characterise the cellular structure. Raman spectroscopy, wide-angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA) and SEM...
The non-linear rheology of the lamellar phase of a polystyrene–polyisoprene diblock copolymer is studied by oscillatory shear experiments. The relaxation of the shear modulus, G(t, γ) is studied as a function of strain amplitude, γ, up to large amplitude strains, γ=100%. The decay of G(t, γ) is analysed using the model-independent CONTIN inverse Laplace transform algorithm to obtain a series of relaxation...
A thermo-sensitive hydrogel was synthesized by irradiation of an aqueous solution of poly(methyl vinyl ether) (PMVE) with electrons. At high polymer concentration a bulk gel was formed. Irradiation of diluted polymer solution at a temperature above the phase transition temperature conserves the structure of the polymer in the phase-separated state. The micro-particles formed under irradiation conditions...
A series of surfactant-free monodisperse latices were prepared with varying glass transition temperatures (Tg) and particle sizes using methyl methacrylate (MMA) and butyl acrylate (BA) monomers. Latices with Tgs between −11 and 105°C were synthesized by varying the MMA to BA ratio during batch polymerization. The particle size of latices with a Tg of 19°C was varied by independently changing temperature,...
Epitaxial crystallization of isotactic poly(1-butene) (iPBu) is performed on different substrates, which help expand the range of interactive substrates used in a previous study. All three crystal forms of iPBu1, which rest on different helix and unit-cell geometries and symmetries, have been produced by epitaxial crystallization. The different epitaxial interactions are discussed. Epitaxial crystallization...
This paper is concerned with the thermal degradation of poly(vinyl alcohol), both in the solid and molten state. Initially, thermal degradation in the solid state was considered to be due to the elimination of hydroxyl side groups, but this process should have produced appreciable amounts of isolated and conjugated polyenes in the degradation residue and small amounts of carbonyl group were detected...
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