술폰화된 폴리스티렌 이오노머 용액과 멤브레인의 유변학적, 물리적 특성
55권 1호, pp. 56-62,
2월 2018
10.12772/TSE.2018.55.056
PDF
요약
The rheological properties of sulfonated polystyrene (SPS) ionomer solutions were found to be significantly affected by solvent polarity, counterion, sulfonation level, and temperature. In the dilute concentration regime, the reduced viscosity (ηred) of SPS solutions in the dimethyl sulfoxide (DMSO), which is a polar solvent, increased with decreasing concentration, whereas opposite effects were observed in low-polarity solvent tetrahydrofuran (THF). H-SPS solutions in THF showed typical shear-thinning behavior over all the measured frequencies, while solutions in DMSO showed shear-thickening behavior at low shear rates, followed by shear-thinning behavior at higher shear rates. These different behaviors might result from differences in polymer–solvent interactions and the chain conformation. SPS solutions in DMSO containing monovalent ions (Na+) exhibited higher dynamic viscosity values than those with divalent ions (Ca2+, Mg2+) because of the different degrees of chain expansion. In DMSO, the dynamic viscosity increased with temperature, regardless of the sulfonation level and counterion. Both the proton conductivity and methanol permeability of the SPS membranes increased with increasing sulfonation level and exhibited an abrupt increase between 10 and 15 mol%, indicative of a percolation threshold.
통계
2022년 11월부터 누적 집계
동일한 세션일 때 여러 번 접속해도 한 번만 카운트됩니다. 그래프 위에 마우스를 올리면 자세한 수치를 확인하실 수 있습니다.
