The effects of additives in aqueous threadlike micellar systems formed with cetyltrimethylammonium bromide (CTAB) were studied by means of dynamic viscoelastic and
1H-NMR techniques. Additives were
ionic aromatic compound, sodium
p-toluenesulfonate (Na
pTS), and
noionic ones / styrene (St) , and toluene (Tol). When a ratio (
CS/
CD) of the concentration of Na
pTS (
CS) to the concentration of CTAB (
CD) was 0.3, 0.4, and 0.5, the longest relaxation time (τ
m) became longer with increasing St (or Tol) concentration [St] (or [Tol]). This suggests that St (or Tol) interacts with CTA
+ at the micellar surface and a threadlike micelle grows longer as [St] (or [Tol]) increases. When
CS/
CD = 1, τ
m became shorter with increasing [St] (or [Tol]). This finding suggests that St (or Tol) is solubilized in the deep interior of threadlike micelles and the mechanical strength of threadlike micelles becomes weak with [St] (or [Tol]).
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