Jump to main content
Jump to site search


Rheological behavior and mechanism of pH-responsive wormlike micelles variation induced by isomer of phthalic acid

Abstract

Responsive wormlike micelles (WLMs) constructed by different carboxylic acids are fascinating. Among them, it is unknown that how the position of carboxylic groups alters the stimuli-response in wormlike micellar systems. Here in, three pH-responsive WLMs based on Gemini-like surfactants (named as o-EAPA, m-EAPA and p-EAPA respectively) were formed and studied through the complexation of N-erucamidopropyl-N, N-dimethylamine (UC22AMPM) and o-phthalic acid (o-PA), m-phthalic acid (m-PA), p-phthalic acid (p-PA) at the molar ratio of 2:1. The viscoelasticity, phase behavior and aggregate microstructure were separately explored by rheological, appearance observation and cryo-TEM methods. The results show that all phthalic acids can protonate UC22AMPM, thereby forming WLMs. However, with the shorter spacer distance between two carboxyl groups in phthalic acid, o-EAPA exhibits the longer length scale of aggregates and more efficient thickening ability compared to other two systems. The similar results in the N, N-dimethyl oleoaminde-propylamine (DOAPA) and o-PA, m-PA, p-PA systems further verify the applicability of this mechanism. Besides, the phthalic acid based WLMs are found to exhibit intriguing pH-responsive behaviors with reversibility, which could be promptly switched between high elastic system and low viscosity fluid by pH control. The o-EAPA system possesses larger viscosity maximum, which produces more precipitous viscosity changes as pH varies. This study is beneficial to formulate pH-responsive WLMs and to determine their advantages for applications.

Back to tab navigation

Publication details

The article was received on 06 Mar 2018, accepted on 16 Apr 2018 and first published on 16 Apr 2018


Article type: Paper
DOI: 10.1039/C8SM00467F
Citation: Soft Matter, 2018, Accepted Manuscript
  •   Request permissions

    Rheological behavior and mechanism of pH-responsive wormlike micelles variation induced by isomer of phthalic acid

    W. Kang, Y. Zhao, P. Wang, Z. Li, X. Hou, Z. Huang and H. Yang, Soft Matter, 2018, Accepted Manuscript , DOI: 10.1039/C8SM00467F

Search articles by author

Spotlight

Advertisements