摘要
粘度测定法研究了十六烷基三甲基溴化铵在０．２ＭＮａＢｒ溶液中在３０～５０℃温度范围内的球－棒转变．溶液粘度的增大是由于棒形胶束的生成．发现溶液粘度随表面活性剂浓度呈指数函数关系变化而不出现转折点，说明胶束的球－棒转变是一个逐步进行的过程．用高分子稀溶液的粘度理论计算了实验温度下各浓度表面活性剂溶液的特性粘度［η］、棒形胶束的轴比Ｊ、棒长Ｌ及棒形胶束的表观流体力学半径Ｒｈ。计算结果表明，流体力学半径Ｒｈ随温度的升高而减小，在所研究的浓度范围内从３０℃时的４４．５ｎｍ减小至５０℃时的６．６ｎｍ．
Viscosities of aqueous solutions of cetyltrimethylammonium bromide in the presence of NaBr(0.2 M)have been measured by an ubbelohde-type capillary viscometer over a range of teinperatures(30℃ to 50℃).The increase in viseosities is due to the formation of rod-shaped micelles.At-high ionic strengths,rod-shaped micelles can be considered similar to neutral polymers dissolved in good solvents since the micellar surface charge is shielded by the ionic atmo sphere and electrostatic interactions are greatly diminished.The sphere-to-rod transition would be a gradual process since the changes in vixcosities with CTAB concentration in the presence of 0.2 M NaBr correspond to an exponential function.without a breakpoint.The intrinsic viscosity,[η],axial ratio,J,length of rod-like micelle,L,and the apparent hydrodynamic radius,Rh,of rod-like micelle of CTAB at various concentrations have been calculated using the theory of the intrinsic viscosity for dilute solutions of linear polymers,the hydrodynamic radiums of , the piculles,R,was found to the range of CTAB concentrations examined.
出处
《江西师范大学学报（自然科学版）》
CAS
1996年第1期16-22,共7页
Journal of Jiangxi Normal University(Natural Science Edition)
