The measured reduced viscosity\|concentration ( η \-\{sp\}/ c\|c ) curves of miscible PPO/PS、 immiscible PMMA/PS mixtures with different composition in toluene all deviate from linear and reveal downward turn in ext...The measured reduced viscosity\|concentration ( η \-\{sp\}/ c\|c ) curves of miscible PPO/PS、 immiscible PMMA/PS mixtures with different composition in toluene all deviate from linear and reveal downward turn in extremely dilute concentration region. Moreover, in the extremely dilute concentration region, the η \-\{sp\}/ c\|c curve of immiscible PVC/PS mixture solution shows upward turn in THF, while shows downward turn in DCE. These experimental facts indicate that such viscosity anomaly is not dependent of miscibility, but resulted from wall effects. Regarding the polymer mixture as a single solute, the interference of wall effects on viscosity measurement could be eliminated quantitatively with a proposed theoretical formula. After corrected, the true viscosity data of mixture shows normal linear η\-\{s p\}/ c\|c curve in the dilute and extremely dilute concentration region.展开更多
文摘The measured reduced viscosity\|concentration ( η \-\{sp\}/ c\|c ) curves of miscible PPO/PS、 immiscible PMMA/PS mixtures with different composition in toluene all deviate from linear and reveal downward turn in extremely dilute concentration region. Moreover, in the extremely dilute concentration region, the η \-\{sp\}/ c\|c curve of immiscible PVC/PS mixture solution shows upward turn in THF, while shows downward turn in DCE. These experimental facts indicate that such viscosity anomaly is not dependent of miscibility, but resulted from wall effects. Regarding the polymer mixture as a single solute, the interference of wall effects on viscosity measurement could be eliminated quantitatively with a proposed theoretical formula. After corrected, the true viscosity data of mixture shows normal linear η\-\{s p\}/ c\|c curve in the dilute and extremely dilute concentration region.