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篇目详细内容 |
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【篇名】 |
Investigation on the Brill transition of polyamide 618 |
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【刊名】 |
Frontiers of Chemistry in China |
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【刊名缩写】 |
Front. Chem. China |
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【ISSN】 |
1673-3495 |
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【EISSN】 |
1673-3614 |
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【DOI】 |
10.1007/s11458-007-0002-z |
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【出版社】 |
Higher Education Press and Springer-Verlag |
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【出版年】 |
2007 |
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【卷期】 |
2
卷1期 |
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【页码】 |
6-12
页,共
7
页 |
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【作者】 |
XIAO Dan;
CUI Xiaowen;
LI Weihua;
YAN Deyue;
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【关键词】 |
Brill transition; polyamide 618; conformation; triclinic; pseudo-hexagonal |
【摘要】 |
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The Brill transition of even–even polyamide 618 was investigated using differential scanning calorimetry (DSC), temperature-dependent wide angle X-ray diffraction (WAXD) and Fourier transform infrared (FTIR). The X-ray diffraction results indicate that the melt-crystallized sample of polyamide 618 transforms from the triclinic unit cell to the pseudo-hexagonal phase in the range of 120–180°C. In this range, the thermograph of polyamide 618 presents a broad endothermal peak. From the FTIR spectra, it was found that during the transition process of polyamide 618, the intensity of the intra-sheet hydrogen bonds becomes weak. At the same time, the CH2–amide bonds twist, and the all-trans conformation of methylene sequences is disordered by inserting the gauche conformation. The CH2 segments are in a mobile state because of the enhanced stretching and twisting vibrations of the C–CO and C–N bonds. |
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