Solvent permeability of dissolved polymer material. Its direct determination from sedimentation measurements
Solvent permeability of dissolved polymer material. Its direct determination from sedimentation measurements
复制标题
溶解的聚合物材料的溶剂渗透性。
DOI：
10.1039/tf9716701837
复制
发表时间：
1971
影响因子：
--
通讯作者：
W. Jaspers
中科院分区：
文献类型：
--
作者：
P. Mijnlieff;W. Jaspers
Sedimentation coefficients have been measured for samples of poly-α-methylstyrene (PAMS) in toluene and in cyclohexane as a function of molecular weight, concentration and temperature.
Considering the analogy, at high polymer concentrations, between the sedimentation of a polymer in a solvent and the permeation of solvent through a porous plug of polymer material a general relation, based on irreversible thermodynamics, between the sedimentation coefficient and the permeability, was derived and applied to the measured sedimentation coefficients.
At low temperature, the permeability in cyclohexane (poor solvent) was about three times as high as that in toluene (good solvent). This difference is ascribed to local associations in the poor solvent, because the permeability in the poor solvent decreases strongly as the temperature is raised.
In calculations of the frictional coefficient of polymer coils, permeability has hitherto been an unknown quantity with an adjustable value. The present investigation shows that permeabilities can now be determined direct from sedimentation measurements at finite concentration.
