The Effect of different environments on the mass transport in POly(Ethylene Terephthalate)

• Main Authors: Shyh Horng, Shore, 蕭世宏
• Other Authors: Hao Ouyang
• Format: Others
• Language: zh-TW
• Published: 1998
• Online Access: http://ndltd.ncl.edu.tw/handle/64254397778844208925

碩士 === 國立中興大學 === 材料工程學研究所 === 86 === Abstract Acetone and ethyl acetate are used as the solvents for the study ofmass transport in Poly(Ethylene Terephthalate)(PET). Based on Harmon's modelfor Case I(Fickian),Case II(swelling) and anomalous transport,the data of mass uptake were analyzed. Pure Case I or Case II behavior did not appear in the both PET-solvents system and is affected by the atmosphere and preheatingmedium. The mass transport in PET is accompanied by a large-scale structural rearrangement,which leads to the induced crystallization of the original amorphous state. Solvent-induced crystallization was confirmed by optical microscopy (OM),X-ray diffraction (XRD),and Differential Scanning Calorimeter(DSC),which is quite different from the thermal crystallization. The density of specimen was measured by the Archimedes' principle,which can be used to estimate the weight percent of crystallites in the sample. The density ofspecimen annealed in air was approximately the same as that annealed in vacuum. The equation of Gibbs-Thomson is empolyed to explain the relationshipof crystal-thickness and melting points obtained by DSC.