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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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