Showing papers in "Polymer in 1998"

TL;DR: In this article, a series of aliphatic polyesters of the polylactide-type were studied by 13 C n.m. and vibrational spectroscopies, where fundamental vibrations were correlated to bands characterising morphology, conformation and configuration of these different polymers.

TL;DR: The crystallization characteristics of poly( l -lactide) (PLLA) films of different molecular weights have been studied by differential scanning calorimetry, optical microscopy and a depolarized-light intensity (d.l.i.) method as mentioned in this paper.

TL;DR: In this paper, contact angle measurements of a high-temperature-vulcanized polydimethylsiloxane (PDMS) elastomer have been obtained for different periods of time in dry air.

TL;DR: The controllable microstructure of the polymers from benzoxazines prepared by cationic polymerization offers opportunities to prepare and optimize the polymer structure for specific applications as mentioned in this paper.

TL;DR: In this paper, the extent of fibre orientation was measured by green strength measurements and the effectiveness of green strength measurement in finding the degree of fiber orientation was also analyzed to investigate their performance.

TL;DR: In this article, the structure, doping, conductivity and thermal stability of reduced polyaniline (PANI-R) were studied by elemental analysis, FT-i.r., solid-state 13C-NMR, XPS and TGA.

TL;DR: In this paper, a study of the mechanical properties and structural heterogeneity of crosslinked polymers formed by photopolymerization of multifunctional monomers is described. But the results indicate that the structural heterogeneity increases as the crosslinking density of the copolymer is increased.

TL;DR: A review of the role of metastability in phase and phase transition behaviors can be found in this paper, where the authors describe the general principles of metastable in polymer phases and phase transitions and provide illustrations from current experimental works.

TL;DR: In this paper, the authors investigated the relationship between various parameters of superabsorbent polymers, including the ultimate degree of absorption and rate of absorption, and the ratio of crosslinker to monomer for different polymerisation systems.

TL;DR: In this article, an aqueous micellar polyacrylamides hydrophobically modified with a small amount of HMPAM was prepared by means of an annealing mousellar polymerization technique, where the hydrophobic molecules were randomly distributed as blocks in the acrylamide backbone.

TL;DR: In this article, an X-ray diffraction investigation has been made of the crystal structure to determine the distribution of hydrogen bonds, to understand the crystalline thermal expansion and to determine influence of water on the polymer crystals and crystallisation process.

TL;DR: In this paper, the properties of commercial samples with heterogeneous distribution of the substituents and laboratory-made samples, with a more homogeneous distribution, are compared to allow a better understanding of the thermogelation process of methylcelluloses.

TL;DR: In this paper, the relationship between morphology and micromechanical deformation processes in various toughened and particle-filled semicrystalline polymers with different types of modifier particles was investigated by high voltage electron microscopy and scanning-EM using in situ tensile techniques.

TL;DR: In this paper, polyurethane (PU) ionomers and non-ionomers with various soft segment contents (SSC) and lengths have been synthesized from polycaprolactone diols (PCL), 4,4′-diphenylmethane diisocyanate (MDI), 1,4-butanediol (BD) and dimethylolpropionic acid (DMPA), and tested for shape memory behaviour as well as for mechanical and dynamic mechanical properties.

TL;DR: In this article, the cold drawing behavior of a range of unoriented linear polyethylenes was investigated using the technique of simultaneous small-and wide-angle X-ray scattering during deformation.

TL;DR: The dynamic flammability properties of an intumescent fire retardant polypropylene filled with ammonium polyphosphate, pentaerythritol and melamine was discussed in this paper.

TL;DR: In this article, a flexible, starch-based plastics of native corn, potato, waxy corn and wheat starch were produced by compression molding mixtures of native starch and glycerol in the weight ratio 0.112 and 0.422.

TL;DR: The α and β phases of isotactic polypropylene form a pair of crystal phases which are characterized by the fact that the less stable β phase has a faster growth rate than the more stable α phase in a large central part of the crystallization range as mentioned in this paper.

TL;DR: In this paper, six different schematic models for micromechanical deformation processes are proposed, which are described in form of a three-stage-mechanism, with the concept of energy dissipation and stress states.

TL;DR: In this article, the authors investigated the mechanism for primary nucleation in polymer crystallization and found that pre-nucleation density fluctuations play an integral role in nucleation of polymer crystallizaticn.

TL;DR: In this paper, a phosphorus-containing epoxy resin (ODOPB) was used as a reactive flame-retardant in o-cresol formaldehyde novolac epoxy resins for electronic application.

TL;DR: In this article, three different types of polyester-polyether copolymers were synthesized by PEG initiated ring-opening polymerization of ϵ-caprolactone.

TL;DR: In this article, the equilibrium melting point of polypropylene has been determined as a function of pressure and the principal technique used, to be reported in this paper, was the Hoffman Weeks plot of melting point versus crystallization temperature.

TL;DR: In this paper, the bulk crystallization behavior of poly(tetramethylene succinate) (PTMS) has been studied in terms of cooling rate and supercooling.

TL;DR: In this article, a model for phase continuity in polymer blends based on geometrical requirements for co-continuous structures has been developed, where the minor phase of a fully cocontinuous blend is considered as a dispersion of randomly oriented rods at their maximum packing density in the major phase.

TL;DR: In this article, the β-nucleating agent was applied to β-plastic samples and the yielding behavior was analyzed on the basis of Eyring's theory, which implied that local melting and crystallization occurred during cold drawing and gave powerful support to Flory's model of the deformation mechanism of crystalline plastics.

TL;DR: The phase separation mechanisms involved were found to be greatly dependent on the initial modifier concentration and on the ratio of the phase separation rate with respect to the polymerization rate, and phase separation proceeded by spinodal demixing.

TL;DR: In this paper, the swelling of a DGEBA/DDA epoxy resin has been investigated and it has been found that the swelling lags behind the behaviour predicted from the ideal mixing law.

TL;DR: In this article, the effect of matrix properties, i.e., crystallinity and molecular weight, on the impact behavior of polypropylene-EPDM blends was studied on a twin-screw extruder.

TL;DR: Baked starch foams were characterized by several physical methods in order to better understand the relationship between process parameters and starch foam structure as discussed by the authors, showing that foam density and strength increase with increasing starch concentration, molecular weight and amylose content.