High-temperature X-ray diffraction studies on the crystalline transitions in the alpha- and gamma-forms of nylon-6
Metadata of CSIR Papers
View Archive Info| Field | Value | |
| Title |
High-temperature X-ray diffraction studies on the crystalline transitions in the alpha- and gamma-forms of nylon-6
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| Creator |
Ramesh, C
Gowd, EB |
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| Subject |
Polymer Science
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| Description |
The crystallization of nylon-6 from the melt was monitored in situ by X-ray diffraction. The nylon-6 was found to crystallize into a high-temperature alpha'-phase as indicated by the two-peak nature of the diffractogram. On cooling from the crystallization temperature to room temperature, nalon-6 retained the two-peak nature. However, data analysis indicates a change from high temperature (HT) alpha'-phase to low-temperature alpha -phase at similar to 180 degreesC. On heating, the a-phase transformed into the alpha'-phase at about 190 degreesC and melted in the alpha'-phase. The transition took place over a temperature range where both phases coexisted. However, samples crystallized from the melt at temperatures 140 and 180 degreesC showed the alpha -phase at room temperature, but on heating the alpha -phase first transformed into a pseudohexagonal phase and before melting the pseudohexagonal phase further transformed into the alpha'-phase. The alpha -phase was transformed into the gamma -phase, by potassium iodide-iodine treatment, and the behavior of the gamma -phase with temperature had been studied for the first time. The gamma -phase was very stable and did not show any crystalline transition below the melting point.
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| Publisher |
AMER CHEMICAL SOCWASHINGTON1155 16TH ST, NW, WASHINGTON, DC 20036 USA
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| Date |
2011-09-24T08:41:08Z
2011-09-24T08:41:08Z 2001 |
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| Type |
Article
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| Identifier |
MACROMOLECULES
0024-9297 http://hdl.handle.net/123456789/24066 |
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| Language |
English
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