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Published on: February 7, 2017
Conformation of drawn poly(trimethylene terephthalate) studied by solid-state 13C NMR
Tsunenori Kameda1, Mitsuhiro Miyazawa, Shigemitsu Murase
1National Institute of Agrobiological Sciences, Tsukuba, Ibaraki 305-8634, Japan.
Abstract:
The change in the conformation of the flexible O-CH2-CH2-CH2-O segment of poly(trimethylene terephthalate) (PTT) monofilament caused by drawing was investigated by means of the gamma-gauche effect on the 13C solid-state NMR chemical shift of the internal methylene carbon, combined with the NMR relaxations. The conformation around the O-CH2 and CH2-O bonds for as-spun fiber was trans/trans. On drawing, followed by heat treatment, the conformation changed to gauche/gauche. The ratio of gauche/gauche to trans/trans for the drawn PTT fiber was determined quantitatively.
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