| Summary: | 碩士 === 逢甲大學 === 紡織工程學系 === 88 === The aims of this work focus the effect of the repeating mit of methylene on the terephthalate polyesters, say Polyethylene terephthalate, Polytrimethylene terephthalate, and Polybutylene terephthalate. Thermal properties, crystallization, degradation behaviours of them were studied with the instruments of DSC, TGA, and HSPM. Their structures were analyzed using SEM after chemical etching and X-ray diffractometer trace.
Results show that the crystallization rate of above three polymers is followed in order by PBT, PTT, PET the Avrami exponents obtained from isothermal crystallization conditions and the Ozawa exponents from nonisothermal crystallization conditions show that all of polymers, present in 3-Dimention structure. The X-ray diffraction peaks of all polymers are not varied in spite of crystallization conditions. A spherulitic structure can be found after chemical etching in all of them.
The PET, PTT, and PBT follow the degradation kinetic data from nonisothermal conditions obtained using a Doyle-Ozawa integral in order. An Arrhenius equation based initial degradation energy, says in the 0.5% of initial weight loss, in this. study.
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