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Thermoplastic polyurethane(TPU) is a linear block copolymer which composedof immiscible soft-segments and rystalline hard- segments in a three dimensionalmatrix. The inherent microphase separation within the matrix structure hasgreat influence on the physcial properties of the elastomer. This study employsFourier- Transform infrared spectrophotometer(FTIR) technique, together with thedifferential scanning calorimetry(DSC),the thermogravimetry (TG), the analysesof hardness, water absorption and tensile stress-strain, to investigate and the relationship between the degree of microphase separation of the elastomerphysical structure andproperties of the polymer. In the FTIR spertrum of theTPU samples, having a higher degree of hydrogen-bond ratio indicates thesample has a higher degree of microphaseseparation. And from the DSC data, aclear evidence of microphase separation,this means that the elastomers possesa two-phase morphology. In genernal,elastomers having a higer degree of microphase separation will have highervaule of hardness, Young's modulus, ultimate stress and lower water absorption,also less elongation ratio. Futherstudies on the samples with DSC and TGA for the cracking temperatures of chiphas found that all the Tgs,Tgh,Tm,Td and activation energy increases with theincrese of the degree of microphase seprartion. The Tgs also shows a largerange of temperature variation as well. Also it was found that a sample withhigher cracking temperature willhave more rapid rate of heat loss when theheating exceeds the crackingtemperature.
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