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Physics, 10.07.2019 23:40 Goldenstate32

Asample of poly(1,4-phenylene sulphide) (pps) is known to have a glass transition tem- perature of 89°c, a cold-crystallization temperature of 137°c and a melting temperature of 278°c. sketch the heat-flux differential scanning calorimetry (dsc) trace you would expect to observe on heating a completely amorphous specimen of this pps from 25°c-325°c labelling the axes and each of the thermal events you show. a sample of this pps (15.3 mg) that had been annealed at 150°c for 1 h was analysed by dsc using a heating rate of 20°c min and the area of the melting endotherm found to be 192.55 mw k. melting of indium (23.2 mg) was used for calibration and gave a melting endotherm of area 216.87 mw k on heating at 20°c min. given that the enthalpy for melting of indium is 28.6 j g and that the enthalpy of melting for 100% crystalline pps is 55.9 j g, calculate (a) the dsc instrument calibration factor, kpsc (b) the enthalpy of melting and degree of crystallinity of the annealed sample of pss a 1 n- he

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Asample of poly(1,4-phenylene sulphide) (pps) is known to have a glass transition tem- perature of 8...

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