ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Ihre E-Mail wurde erfolgreich gesendet. Bitte prüfen Sie Ihren Maileingang.

Leider ist ein Fehler beim E-Mail-Versand aufgetreten. Bitte versuchen Sie es erneut.

Vorgang fortführen?

Exportieren
Filter
Sammlung
Verlag/Herausgeber
Erscheinungszeitraum
  • 1
    Digitale Medien
    Digitale Medien
    Weinheim : Wiley-Blackwell
    Angewandte Makromolekulare Chemie 221 (1994), S. 137-153 
    ISSN: 0003-3146
    Schlagwort(e): Chemistry ; Polymer and Materials Science
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Physik
    Beschreibung / Inhaltsverzeichnis: Der Einfluß der Verarbeitungsbedingungen auf die Morphologie und die mechanischen Eigenschaften von unidirektionalen Composites aus Poly(ethylenterephthalat) und Glasfasern wurde untersucht. Im ersten Teil dieser Arbeit wurde über den Einfluß von Glasfasern auf die Kristallisationskinetik und die Matrixmorphologie von Poly(ethylenterephthalat)(PET) berichtet. Dabei wurden die Schmelz-und Kristallisa-tionsbedingungen, die thermische Stabilität und die Zugabe von Kristallisationskeimen (Talkum und Natriumbenzoat) berücksichtigt. Auf der Grundlage dieser Ergebnisse wurden mit Glasfasern gefüllte PET-Streifen unter verschiedenen Bedingungen zu Preßformplatten verarbeitet. Dynamische und statische Kurzzeit-Scherversuche sowie Langzeit-Biegefestigkeitsversuche wurden durchgeführt und unter Berücksichtigung der Verarbeitungsbedingungen und der Mikrophasenstruktur analysiert.
    Notizen: The aim of this study was to understand how changes in processing conditions affect the morphology and ultimately mechanical performances of unidirectional poly(ethylene terephthalate) / glass fibre composites. In a previous paper, we have presented the influence of fibres on the crystallization kinetics and on the matrix morphology of poly(ethylene terephthalate) (PET), considering fusion-crystallization conditions, thermal stability and the addition of nucleating agents in the matrix (talc or sodium benzoate). Based on the results of that crystallization study, various processing conditions were implemented on compression-moulded plated made from PET-glass pultruded ribbons. Short-term (dynamic and static) shear tests and long-term flexural fatigue tests were performed to characterize the effects of moulding conditions. The mechanical results were analysed considering both processing conditions and microstructural parameters.
    Zusätzliches Material: 6 Ill.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 2
    ISSN: 0025-116X
    Schlagwort(e): Chemistry ; Polymer and Materials Science
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Physik
    Notizen: The nature of interactions between polyethylene and a non-wetting solute was analyzed to know if the interface can be characterized by the expression of the energy of wetting or if phenomena other than adhesion and wetting must be taken into account. In this way, the isotherms of sorption, the molar heats of interaction, the kinetic behaviour of the sorption, the permeation, and the changes of length during liquid immersion gave informations on the existence of a limited diffusion into the polymer. Two types of systems were investigated: polyethylene/water and polyethylene/methylene iodide. The formation of aggregates is discussed.
    Zusätzliches Material: 9 Ill.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 3
    ISSN: 0025-116X
    Schlagwort(e): Chemistry ; Polymer and Materials Science
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Physik
    Notizen: Dynamic viscoelastic analysis was used to continuously follow the “cold crystallisation” of poly(ethylene terephthalate) (PET) test bars. Samples which were cut from an amorphous PET sheet were heated to a given temperature in a hot cell. The evolution of the real part of the modulus not only allows the kinetic crystallisation parameters but also the nucleation and growth characteristics to be determined. This method was applied to unidirectional PET/glass fibre composite strips. Thus, the influence of the glass fibres on the morphological and kinetic characteristics of the matrix crystallisation has been investigated.
    Zusätzliches Material: 13 Ill.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 4
    Digitale Medien
    Digitale Medien
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 185 (1984), S. 601-613 
    ISSN: 0025-116X
    Schlagwort(e): Chemistry ; Polymer and Materials Science
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Physik
    Notizen: Differential scanning calorimetry and thermomechanical analysis are used for examining the thermal behaviour of amorphous poly(ethylene terephthalate) films in the glass-transition range. By variation of the heating rate between 0,2 and 100 K. · min-1, it is possible to obtain either an exotherm associated with a shrinkage, or an endotherm, or both of these phenomena. It is found that very low heating rates not only give rise to a retardation mechanism but also to a molecular rearrangement.
    Zusätzliches Material: 7 Ill.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 5
    ISSN: 0025-116X
    Schlagwort(e): Chemistry ; Polymer and Materials Science
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Physik
    Notizen: In order to correlate crystallinity and dynamic mechanical properties, poly(ethylene terephthalate) (PETP) samples were prepared and subjected to viscoelastic measurements. The evolution of the glass-rubber transition is analyzed for samples annealed at different temperatures. Multiplexing analysis allows to draw the Cole-Cole plot and to develop a rheological model for the polymer behaviour. In the case of the amorphous PETP, the asymmetric Cole-Cole plot may be represented by a “biparabolic” rheological model. On the other hand, for the semi-crystalline polymer, the Cole-Cole plot is symmetrical and the corresponding rheological model is the “liquid Cole” one. Dielectric spectroscopy experiments are in good agreement with the previous method. Particularly, the Cole-Cole plot for semi-crystalline samples is perfectly symmetric. The previous rheological models with, in addition, a static modulus are applicable to glass-fibre reinforced PETP. These new models are called “limited biparabolic” and “Zener parabolic” model, respectively.
    Zusätzliches Material: 16 Ill.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 6
    Digitale Medien
    Digitale Medien
    Weinheim : Wiley-Blackwell
    Angewandte Makromolekulare Chemie 188 (1991), S. 129-142 
    ISSN: 0003-3146
    Schlagwort(e): Chemistry ; Polymer and Materials Science
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Physik
    Beschreibung / Inhaltsverzeichnis: The changes in the electrical features of bonded joints stainless steel/adhesive film/stainless steel are followed against aging time in a hot moist environment by using non-destructive electrical impedance measurements. It is shown that the ingress of moisture into the bonded joint leads to a decrease in resistance at low frequencies and to an increase of the dielectric constant of the adhesive. This sorption of water results from two simultaneous processes: -  bonding of water molecules with the active sites of the polymer chains leading to a relaxation at low frequencies. -  diffusion of free water in the bonded joint, leading to an increase in the permittivity of the adhesive at high frequencies.The relative proportion of the bonded water and free water is also given.In addition, it is shown that the water sorption kinetics varies with the nature of the surface pretreatment of the metallic substrate.All these data are in agreement with those obtained by dynamic mechanical thermal analysis.
    Notizen: L'évolution des caractéristiques électriques d'un assemblage collé acier inoxydable/adhésif en film/acier inoxydable est étudiée en fonction du temps de vieillissement en atmosphère chaude et humide. A partir de mesures non destructives d'impédance électrique, il est montré que l'absorption d'eau par le joint conduit à une diminution de sa résistance en basse fréquence et à un accroissement de sa constante diélectrique. La sorption d'eau dans le joint résulte de deux processus simultanés: -  La fixation de molécules d'eau sur les sites polaires de l'adhésif. Ce phénomène est caractérisé par une dispersion électrique croissante en basse fréquence. -  La migration d'eau libre dans des microcavités. Ce phénomène entraîne un accroissement de la permittivité en haute fréquence.La proportion relative de ces deux phases (eau structurale et eau libre) est également donnée.D'autre part, ce travail montre que la nature du traitement de surface du métal provoque une modification de la cinétique de sorption d'eau.Ces résultats sont en accord avec ceux obtenus par analyse thermomécanique dynamique.
    Zusätzliches Material: 5 Ill.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 7
    Digitale Medien
    Digitale Medien
    Weinheim : Wiley-Blackwell
    Angewandte Makromolekulare Chemie 212 (1993), S. 19-33 
    ISSN: 0003-3146
    Schlagwort(e): Chemistry ; Polymer and Materials Science
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Physik
    Beschreibung / Inhaltsverzeichnis: Der Einfluß von Glasfasern auf die Kristallisationskinetik und die Matrixmorphologie von Composites aus Poly(ethylenterephthalat) und Glasfasern wurde untersucht. Die Schmelz- und Kristallisationsbedingungen, die thermische Stabilität und die Addition von Kristallisationskeimen (Talkum oder Natriumbenzoat) wurden ebenfalls berücksichtigt. Der Einfluß dieser Additive auf die Kristallisation überwiegt den der Verstärkungsfasern. Darüber hinaus fördern Scherspannungen an der PET/Glasfaser-Grenzfläche das Wachstum einer anderen kristallinen Überstruktur.
    Notizen: This paper presents the influence of glass fibres on crystallization kinetics and on matrix morphology for poly(ethylene terephthalate) (PET)/glass fibre composites. The following parameters are also considered: fusion-crystallization conditions, thermal stability and the addition of nucleating agents in the matrix (talc or sodium benzoate). It clearly appears that the influence of those additives on the crystallization of PET is predominant compared to the effect of stiffening fibres. Moreover, the application of shear stresses at the PET/glass fibre interface promotes the growth of a different crystalline superstructure.
    Zusätzliches Material: 12 Ill.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 8
    Digitale Medien
    Digitale Medien
    Weinheim : Wiley-Blackwell
    Macromolecular Chemistry and Physics 195 (1994), S. 3949-3961 
    ISSN: 1022-1352
    Schlagwort(e): Chemistry ; Polymer and Materials Science
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Physik
    Notizen: The diffusion-limited thermodegradation of a poly[ethylene-co-(methyl acrylate)] rubber was studied using an original pinpoint dynamic mechanical analysis (PDMA). The importance of the temperature of the analysis in the physical and mechanical determination of oxidation profiles was clearly illustrated. The variations of the tan δ (δ: loss angle) at the glass transition temperature allows the determination of the apparent activation energy of the diffusion-limited thermooxidation phenomena.
    Zusätzliches Material: 14 Ill.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 9
    Digitale Medien
    Digitale Medien
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 18 (1974), S. 2435-2447 
    ISSN: 0021-8995
    Schlagwort(e): Chemistry ; Polymer and Materials Science
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: Different polyamides and polysulfonamides were prepared by the interfacial polycondensation method. The influence of the experimental condition was specified. The principal characteristics of polymers are indicated (solubilities, molecular weights, IR spectra, thermal stability). In the case of poly(ethylene 1,3-benzenesulfonamide), a study of the thermal behavior was specially developed.
    Zusätzliches Material: 7 Ill.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 10
    ISSN: 0021-9304
    Schlagwort(e): Chemistry ; Polymer and Materials Science
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Medizin , Technik allgemein
    Notizen: Twenty-two cases of vascular graft failures (thrombosis, pseudoaneurysm, dilation, infection) were investigated by means of physicochemical, histological, and ultrastructural studies. A general decrease of mechanical resistance to stress of the prostheses was observed. Its magnitude ranged from 2 to 75% of the values of identical virgin prostheses and there was no relation with the duration of implantation. In addition to the breakage of yarn filaments (SEM), migration of fiber debris (histology) was observed in 7 cases. The structure of the polyester molecule had evolved after implantation. A decrease of crystallinity (x-ray diffraction and differential scanning calorimetry) was noted. These observations raise the question of the established stability of vascular prostheses and emphasize the need for further investigations in human graft retrieval programs.
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
Schließen ⊗
Diese Webseite nutzt Cookies und das Analyse-Tool Matomo. Weitere Informationen finden Sie hier...