| Summary: | 碩士 === 國立臺灣大學 === 材料科學與工程學研究所 === 86 === Abstract
Some fundamental physical properties of C60-based polyether urethane star
polymer would be studied in this work.
From the results of GPC, it was found that the number of arms of star polymer
decreased with increasing the length of arms. Since the core of star polymer
would be exclude from crystal lamellae, the crystallinity of star polymer was
lower than it of corresponding linear polymer from the DSC
measurement. From the
results of POM, it was not observed the spherulite crystal for the star polymer
due to the small size of crystal. However, it was observed the spherulite
morphology for the linear polymer. From the results of DMA, three relaxation
processes for the linear and star polymer in the temperature range -150℃- -
40℃. The high temperature α process was considered to be associated with the
glass-rubber relaxation. The β relaxation was consider to be connected with
water. In dry sample, the β relaxation was not observed. The low temperature
γprocess was considered to be a local sub-glass relaxation process. From the
fitting of DMA spectra utilizing the Havriliak-Negami equation and according to
the model proposed by Schonhals and Schloser, it was found that the excluded
volume around the core of star polymer was significant effect on the relaxation
processes of star polymer.
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