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Copyright of Anwendungsbezogene Physikalische Charakterisierung von Polymeren, Insbesondere im Festen Zustand is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In semicrystalline isotactic Polypropylene the sensitivity to crack propagation can be lowered by the right choice of the molecular composition (atactic content, molecualr weight) and by a controlled production of a certain morphology. Coarse spherulitic morphologies produced by slow undercooling from the melt exhibit the lowest values in respect to yield or fracture stress and fracture toughness. This is due to the fact that plastic deformation is mainly concentrated on the small volume of the weak spherulite boundaries. An improvement of the properties can be reached in this type of morphology when a Polypropylene with a higher content of atactic polymer chains is used. For temperatures under Tg the strength of a material was defined in this work as the product of fracture stress and fracture toughness. Optimum values of strength are measured for fine spherulitic Polypropylene produced by quenching from the melt, especially when the polymer has a relatively high moecular weight. In this type of morphology a dense craze formation in front of the crack tip provides high energy dissipation. Thus crack propagation under static load is rendered more difficult even at low temperatures. [ABSTRACT FROM AUTHOR]

Copyright of Anwendungsbezogene Physikalische Charakterisierung von Polymeren, Insbesondere im Festen Zustand is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Anwendungsbezogene Physikalische Charakterisierung von Polymeren, Insbesondere im Festen Zustand is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Stirling approximation was introduced into the Flory f-functional distribution function for polycondensation, and the accuracy of the resulting expressions was determined. An expression, which can be readily numerically integrated, was found to yield cumulative distributions which agree very well with exact summations of the classic f-functional polycondensation expression for low p and all mer sizes, i, as well as for p up to p = 1/(f − 1) and high i for functionalities, f, in the range 2 < f ⪙ 4. The agreement is quite good for low i and p up to p = 1/(f − 1) and f in the same range, with a clear trend to better agreement for lower f. The expression obtained using the Stirling approximation yields unnormalised i-mer weight fractions. An equation is given which relates the normalisation factor with acceptable accuracy to p and f in the range 2 < f ⪙ 3. [ABSTRACT FROM AUTHOR]

Copyright of Anwendungsbezogene Physikalische Charakterisierung von Polymeren, Insbesondere im Festen Zustand is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Anwendungsbezogene Physikalische Charakterisierung von Polymeren, Insbesondere im Festen Zustand is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A series of low molecular weight $$(\bar M_n < 10,000)$$ block copolymers of composition (L-alanine)n-(L-glutamate)m covering a range of values of m/n from 0.56 to 4.4 have been prepared and characterised. Samples with m/n < 1.3 were shown by low angle laser light scattering to be very highly aggregated in aqueous solutions of ionic strength 0.5 whereas above this ratio the copolymers were monomeric. Circular dichroic spectra of the samples in aqueous media can be interpreted in terms of a conformation consisting of β-sheet structure plus extended structure with a greater proportion of β-sheet structure in the aggregated state most probably associated with the alanine residues. On the addition of methanol the longer chain copolypeptides exhibit a transition to an α-helical conformation. [ABSTRACT FROM AUTHOR]

Copyright of Anwendungsbezogene Physikalische Charakterisierung von Polymeren, Insbesondere im Festen Zustand is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Anwendungsbezogene Physikalische Charakterisierung von Polymeren, Insbesondere im Festen Zustand is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

When compared with results from humid fibers, characteristic changes of the SAXS-pattern taken from dried collagen fibers have been observed. The average lateral width of the various reflexions increases with the order of reflexion whereby a fluctuation is superimposed, the type of which cannot easily be related to the reflexion order. Moreover, each of the reflexions is obviously laterally split into three components. An explanation of these characteristics can be given with the aid of a distinct model, assuming that the collagen fibrils have definitely varying diameters along their axis, whereby paracrystalline distortions appear, represented by nematic fluctuations. Additionally, there is a need for postulating a shear deformation of parts of the sample. [ABSTRACT FROM AUTHOR]

Copyright of Anwendungsbezogene Physikalische Charakterisierung von Polymeren, Insbesondere im Festen Zustand is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Anwendungsbezogene Physikalische Charakterisierung von Polymeren, Insbesondere im Festen Zustand is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

During the compressive deformation of atactic Polystyrene coarse shear bands and/or diffuse shear zones are formed according to the testing conditions. Optical and scanning electron micrographs of these deformation zones and of the resulting fracture surfaces are presented in this paper. With these observations the processes which occur during fracture in the different shear zones can be interpreted. In spite of a macroscopically brittle fracture in the discrete coarse shear bands fine stretched fibrils are found on the fracture surface. They indicate large plastic deformations inside the shear bands before final fracture occurred. From these observations a similarity of the fracture mechanisms in coarse shear bands and crazes of Polystyrene can be deduced. When the plastic deformation only occurs in a broad diffuse shear zone, for example at elevated temperatures, ductile fracture behaviour is observed. In this case the deformation develops by void- and craze-formation and by viscous flow in a large volume of the polymer. [ABSTRACT FROM AUTHOR]

The influence of the cooling conditions and the shear on the mechanical properties of isotactic Polypropylene were investigated. Former works about the crystallization and the morphology (1-5) were the basis. The mechanical properties were discussed by density, Vicat temperature, tensile strength, impact strength and hardness. The differences between the investigated samples were that the tubes crystallized under shear influence and the sheets crystallized without any shear influence. The mass and bath temperatures of tubes als well als sheets and the pressure at crystallization were kept constant. The relations between density, tensile strength, impact strength and hardness, found by other authors (13) with injection moulded Polypropylene, were analogous to ours. The tubes which crystallized under shear influence had rendered higher or equal values of the tensile strength, the tear strain, the impact strength and the hardness than those ones of the sheets which crystallized without any shear influence. These differences cannot be explained by the different cooling media (Silicon oil, water). If the sheets were cooled with water — as the tubes were — both the density and the mechanical properties of the sheets would even be lower than the rendered values because of the higher warmth conductivity of water as that of Silicon oil. Polymorphism of it-PP (10) may provide one explanation, and other the great differences in textures of tubes and sheets (tubes — strong texture; sheets — low texture) found by P. F. Mayer (9). The textures and the polymorph structures are enclosed in certain layers of the samples (2, 11, 14-16). In a later work these influences should be discussed by investigating the mechanical properties of separated layers ("differential") of the samples and then comparing the single values to the integral properties. [ABSTRACT FROM AUTHOR]

Measurements of the longitudinal relaxation time T1 of fractionated polyethylene at temperatures between 77 K and 373 K in a broad frequency range (20 kHz - 100 MHz) are reported. Three discrete processes could be detected and are interpreted by diffusing defects (vacancies, kinks and torsions). [ABSTRACT FROM AUTHOR]

Copyright of Anwendungsbezogene Physikalische Charakterisierung von Polymeren, Insbesondere im Festen Zustand is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Anwendungsbezogene Physikalische Charakterisierung von Polymeren, Insbesondere im Festen Zustand is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Anwendungsbezogene Physikalische Charakterisierung von Polymeren, Insbesondere im Festen Zustand is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Anwendungsbezogene Physikalische Charakterisierung von Polymeren, Insbesondere im Festen Zustand is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Anwendungsbezogene Physikalische Charakterisierung von Polymeren, Insbesondere im Festen Zustand is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Anwendungsbezogene Physikalische Charakterisierung von Polymeren, Insbesondere im Festen Zustand is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Anwendungsbezogene Physikalische Charakterisierung von Polymeren, Insbesondere im Festen Zustand is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

PE-monofilaments are produced by the melt-spinning process. The cooling velocity and the stretch-ratio of the melt were varied as characteristic parameters of the melt-spinning process. By increasing the cooling velocity and the cold drawing of the obtained threads, the elastic recovery after a 25% — elongation can be improved to complete reversibility. From tensile test runs a new deformation mechanism can be identified which explains this behaviour. The main features of this deformation mechanism are that no necking occurs during the deformation and that the deformation of the noncrystalline plays an important role. Apparently this mechanism is correlated with an imperfect crystalline structure. [ABSTRACT FROM AUTHOR]

Copyright of Anwendungsbezogene Physikalische Charakterisierung von Polymeren, Insbesondere im Festen Zustand is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The absorption spectra of polyurethane elastomers consisting of poly(adipine-acid-glycolester) (soft segment) with diphenyl-methyl-diisocyanate and butanediol-1,4 (hard segment) in the far infrared were reported. Spectral changes are studied depending on different hard segment content and different annealing conditions. Drawn samples were studied with a draw ratio up to 360%. The temperature dependence of the spectra was studied (30-300 K). The results are discussed in terms of intermolecular interactions between coupled benzene rings and coupled HN-CO-groups. [ABSTRACT FROM AUTHOR]

PA 6, PA 6,6 and PA 12 films are uniaxially drawn under various drawing conditions. The morphology of the drawn samples is investigated by SALS, polarized light and scanning electron microscopy. All PA films show overlapping scattering figures at higher draw ratios. The correlation between this scattering figures and the morphology is examined and discussed. [ABSTRACT FROM AUTHOR]

The method of inelastic ligt scattering is able to give information about the dynamic properties of a material. It is a spectroscopic method, which is sensitive to siolated and collective translational, rotational as well as vibrational motions. The basic theory of the method is described. The analysis of the inelastic spectrum and the general applications of the technique are discussed. Finally a review is given on the results which have been obtained by this method for solid polymers. [ABSTRACT FROM AUTHOR]

Copyright of Anwendungsbezogene Physikalische Charakterisierung von Polymeren, Insbesondere im Festen Zustand is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Anwendungsbezogene Physikalische Charakterisierung von Polymeren, Insbesondere im Festen Zustand is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Anwendungsbezogene Physikalische Charakterisierung von Polymeren, Insbesondere im Festen Zustand is the property of Springer eBooks and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)