A cationic surfactant, cetyltrimethylammonium
p-toluenesufonate (CTA
pTS), forms long threadlike micelles in aqueous solution. The threadlike micelles make concentrated entanglement networks to show pronounced viscoelastic behavior as well as concentrated polymer systems. However, a responsible mechanism for the longest relaxation mode of the threadlike micellar system is different from that of the polymer system. The threadlike micellar system exhibits unique viscoelasticity described well by a Maxwell model. The longest relaxation time of the threadlike micellar system is not a function of the concentration of CTA
pTS, but of
p−toluenesufonate (
pTS
−) ions in the bulk aqueous phase supplied by added sodium
p−toluenesulfonate (Na
pTS). The rates of molecular motions in the threadlike micelles are not influenced by the concentration of
pTS
− anions, therefore, molecular motions in the threadlike micelles (
micro-dynamics) are independent of the longest relaxation mode (
macro-dynamics). A nonionic surfactant, oleyldimethylamineoxide (ODAO), forms long threadlike micelles in aqueous solution without any additives. The aqueous threadlike micellar system of ODAO also shows Maxwell type viscoelastic behavior. However, the relaxation mechanism for the longest relaxation process in the system should be different from that in the threadlike micellar systems of CTA
pTS, since the system of ODAO does not contain additive anions. Because increase in the average degree of protonation of ODAO head groups in micelles by adding hydrogen bromide lengthens the relaxation time remarkably, changes in
micro-structure and
micro-dynamics in the threadlike micelle are closely related to
macro−
dynamics in contrast with the threadlike micellar system of CTA
pTS.
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