| Summary: | 碩士 === 國立臺灣大學 === 材料科學(工程)研究所 === 81 === The thermal,structure,flow and mechanical properties of PEEK
and its composites were invesigated in this work. The molecular
weights and flow behaviors of three types of PEEK were measured
by capillary and rheometer. The thermal properties were
determin- ed by DSC and TGA,and structure by IR. The molecular
weight of PEEK 2285 is lower than that of PEEK 450G and PEEK
450C. So it flows much easier than the other two. But the
thermal properties and mechanical properties are almost the
same for these three types of PEEK We used DSC to analyze the
isothermal crystallization kineti- cs of PEEKs based on Avrami
equation. The Avrami exponent was be- tween 3 and 4. The rate
constant decreased as temperature is inc- reased in high
crystallization temperature region , but increased as
temperature is increased in low crystallization temperature
region. The use of Kamal model to predict the nonisothermal
crystall- ization kinetics of PEEKs was not satifactory. The
disagreement might be due to the overesimated rate constant in
some temperatu- re region , which could not be obtained
directly from the isothe- rmal data , and the extropolated data
were assumed in simulation.
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