碱金属反离子对聚乙烯吡咯烷酮-十二烷基硫酸盐复合作用的影响

Influence of alkali metal counterions on the complexation of polyvinylpyrrolidone with dodecyl sulfates

研究了十二烷基硫酸锂、钠和钾盐分别与聚乙烯吡咯烷酮(PVP)的复合作用,用表面张力法、电导率法和毛细管电泳法(CE)考察不同水化半径的碱金属反离子对PVP-十二烷基硫酸盐的拟聚电解质类型和电解质强度的影响。表面张力和电导率的实验结果表明,当碱金属反离子水化半径减小时(Li+>Na+>K+),PVP-十二烷基硫酸盐间的缔合量随之增大,且参与反离子架桥作用的反离子数增加;CE实验结果表明,PVP-十二烷基硫酸盐的复合作用形成拟聚阴离子,不会随碱金属反离子水化半径增大而改变拟聚电解质类型,且其拟聚阴离子的电解质强度将随之减弱。

The complexation between polyvinylpyrrolidone(PVP)and dodecyl sulfates with different alkali metal counterions(Li+,Na+and K+)was studied by tensiometry,conductometry and capillary electrophoresis(CE).The effects of these alkali metal counterions with different hydration radii on the pseudo-polyelectrolyte types and electrolyte strength of PVP-dodecyl sulfate complexes were also investigated.The experimental results of tensiometry and conductometry showed that,the association between PVP and dodecyl sulfates and the bridging degree of counterions both increase with the decrease of hydration radii of alkali metal counterions(Li+>Na+>K+).The CE results showed that,the complexation between PVP and dodecyl sulfates has formed pseudo-polyanions no matter what alkali metal counterion is,but the polyanion properties become strong with the decreasing hydration radii of alkali metal counterions.