| Autor: |
S.D. Artamonova, B.A. Arutyunov, Yu. V. Popov, G.P. Andrianova |
| Rok vydání: |
1977 |
| Předmět: |
|
| Zdroj: |
Polymer Science U.S.S.R.. 19:1418-1426 |
| ISSN: |
0032-3950 |
| DOI: |
10.1016/0032-3950(77)90272-6 |
| Popis: |
The orientational crystallization of PETPh has been investigated by calorimetry and X-ray structural analysis for the stretching of the polymer at various temperatures and rates of extension. The temperature boundaries of the region in which crystallization is possible as a consequence of the uniaxial extension of the polymer have been determined, together with the heat effect of this phase change. It is shown that the process of orientational crystallization, occurring at the same time as the extension of the polymer, develops only in quite a narrow temperature region lying in the range 70–94°C. The boundaries of this region are not sensitive to any change in the strain rate within a change by a factor of 10. The kinetics of the reorientational crystallization of PETPh have been investigated within this temperature range and structural investigations of the specimens have been made. By comparing measured values of the change in internal energy in this process with the limiting degrees of crystallinity of the stretched specimens, the heat of the phase change in the orientational crystallization of PETPh has been determined; this was found to be equal to 5·5 cal/g. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
|
