| Type of Document |
Master's Thesis |
| Author |
Kumar, Amit
|
| Author's Email Address |
akumar@vt.edu |
| URN |
etd-06142001-134722 |
| Title |
Morphology, Crystallization and Melting Behavior of Statistical Copolymers of Propylene with Ethylene, 1-Butene, 1-Hexene and 1-Octene
|
| Degree |
Master of Science |
| Department |
Materials Science and Engineering |
| Advisory Committee |
| Advisor Name |
Title |
| Marand, Hervé L. |
Committee Chair |
| Kander, Ronald G. |
Committee Member |
| Reynolds, William T. Jr. |
Committee Member |
|
| Keywords |
- alpha and gamma-phase
- multiple melting
- cross-hatching
|
| Date of Defense |
2001-06-12 |
| Availability |
unrestricted |
Abstract
In this thesis, the morphology, crystallization and melting behavior of polypropylene copolymers (propylene/ethylene, propylene/1-butene, propylene/1-hexene and propylene/1-octene) has been examined. The multiple melting behavior has been correlated with the presence of alpha and gamma phases and with the occurrence of cross-hatching morphology. The Crystallization and melting behavior of propylene/ethylene and propylne/1-butene are qualitatively similar and compatible with the expectations that the ethylene and butene comonomers are partly included in the propylene lattice. Propylene/1-hexene and propylene/1-octene copolymers exhibit remarkably similar behavior and morphologies consistent with the expectations that the hexene and the octene comonomers are rigorously excluded from the crystal lattice.
The origin and the crystallization time dependence of the multiple melting behavior is very different for these two pairs of copolymers. For PE and PB it is consistent with the melting of parent a-phase lamellae and alpha or gamma-phase daughter lamellae. For PH and PO copolymers it is very similar to that observed for ethylene-octene(EO) and ethylene-styrene(ES) copolymers and compatible with the melting of primary lamellae and secondary mosaic or fringed micellar structures.
|
| Files |
| Filename |
Size |
Approximate Download Time
(Hours:Minutes:Seconds)
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| 28.8 Modem |
56K Modem |
ISDN (64 Kb) |
ISDN (128 Kb) |
Higher-speed Access |
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1amit.pdf |
7.49 Mb |
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