Measuring the viscoelastic properties of polytetrafluoroethylene copolymers at ultrasonic frequencies /
and G"(w), of Tefzel 280 (a high molecular weight copolymer
| Main Author: | |
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| Format: | Thesis eBook |
| Language: | English |
| Published: |
[Place of publication not identified] :
[publisher not identified] ;
1994.
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| Subjects: | |
| Online Access: | Link to OAKTrust copy |
| Summary: | and G"(w), of Tefzel 280 (a high molecular weight copolymer exist in the melt state over a wide enough temperature range for superposition, their viscoelastic properties must be frequencies (40-200 kHz). A discrete relaxation spectrum for inference, the spectrum over a wide enough range of insoluble in most common solvents, direct measurement of linear viscoelastic properties of the melt. To make this measured directly. A new technique employing a piezoelectric melting points, this is not possible. Since they do not of ethylene and tetrafluoroethylene) at ultrasonic possible. Instead, the structure must be inferred from the relaxation times to include the plateau modulus, GNI is required. For most polymers this is accomplished by time- Since polytetrafluoroethylene (PTFE) and its copolymers are techniques such as size exclusion chromatography (SEC) is not Tefzel 280 has been determined. temperature superposition, but for PTFE and its copolymers, the viscoelastic properties, GI(w) their molecular weight distribution by conventional ultrasonic composite oscillator has been developed to measure with their burning points being not much higher than the |
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| Item Description: | "Major subject: Mechanical Engineering". Vita. |
| Physical Description: | xxi, 181 leaves : illustrations ; 28 cm. Also available online. |
| Bibliography: | Includes bibliographical references. |