A novel pH-responsive wormlike micellar viscoelastic solution was constructed by a rosin-based anionic surfactant (Na-MPA-AZO-Na) in the presence of cetyltrimethylammonium bromide (CTAB). The viscoelasticity, aggregate morphology, and pH-responsiveness of the pH-responsive wormlike micelles have been investigated through the method of rheology and cryogenic-transmission electron microscopy. Its corresponding mechanism has been studied using H NMR and H-H 2D NOESY HNMR. The zero-shear viscosity (η) of the wormlike micellar solution rapidly decreases by 3 orders of magnitude as the pH increases from 5.21 to 9.56. The viscoelastic fluids and water-like solutions can be converted by tuning the pH between 3.62 and 12.00, and the corresponding aggregates also transform between wormlike micelles and spherical micelles. In addition, the wormlike micellar cross-sectional diameter is approximately 10 nm, which is remarkably larger than that of the common wormlike micelles. The phenomenon can be attributed to the large steric volume of the rosin rigid skeleton. When the pH is 12.00, a "pseudo" Gemini surfactant is constructed by Na-MPA-AZO-Na and CTAB through the electrostatic interactions. Wormlike micelles also can be formed with the increasing concentrations. The η of the wormlike micellar system shows strong dependence on concentration with an exponent of 9.6 (η ∝ ). This work further promotes new applications of forest resources.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/acs.jafc.0c03749 | DOI Listing |
Small
December 2024
Department of Chemistry, Xihua University, Chengdu, 610039, China.
Nano-formulated pesticides are increasingly desired to control the insect pest and plant disease with superior efficacy for guaranteeing the high yield and quality in crop production. However, the impact of nanocarrier morphology on pesticide resistance against rainwash, photolysis, and overall pesticide bioactivity remains unknown. In this work, a series of well-defined and morphology-controllable polymer nanocarriers for pesticide are fabricated through polymerization-induced self-assembly.
View Article and Find Full Text PDFLangmuir
December 2024
Department of Chemistry, Faculty of Science, Nara Women's University, Kitauoyanishi-machi, Nara 630-8506, Japan.
The aggregation properties of sugar-based surfactants with methyl groups at multiple positions on the linear alkyl chain are an understudied topic. Therefore, in this study, we performed a structural analysis of aggregates formed by two types of sugar-based nonionic surfactants with multibranched methyl chains, 3,7,11-trimethyldodecyl maltoside (CMal), as well as with a linear chain, dodecyl--d-maltoside (CMal), in aqueous solutions using rheological and small-angle X-ray scattering techniques. CMal showed an excellent performance in lowering surface tension (28.
View Article and Find Full Text PDFAdv Mater
November 2024
Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China.
To endow non-antibacterial molecules with highly efficient bactericide activity is an important but challenging issue. Herein, a kind of cell-penetrating peptide octa-arginine (R8) is found to be effective in activating antibacterial ability when assembling with anionic surfactant sodium dodecyl sulfate (SDS), while individual R8 or SDS shows poor or no antibacterial ability. By combined electrostatic, hydrogen bond, and hydrophobic interactions, R8 and SDS associate into wormlike micelle and lamellar structure by forming supramolecular self-assembling units, depending on their charge ratio (CR).
View Article and Find Full Text PDFMolecules
November 2024
School of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng 252059, China.
Wormlike micelles (WLMs) with tunable viscoelastic characteristics have emerged as indispensable smart materials with a wide range of applications, which have garnered intense interest over the past few decades. However, quantitatively predicting the effect of various hydrotropes on the rheological behaviors of WLMs remains a challenge. In this article, micelles were formed in a mixture of 3-hexadecyloxy-2-hydroxypropyltrimethylammonium bromide (RHTAB) and aromatic hydrotropes (e.
View Article and Find Full Text PDFSoft Matter
November 2024
Laboratoire Charles Coulomb (L2C), University of Montpellier, CNRS, Montpellier, France.
Gemini surfactants are ideal systems to study a wide range of rheological behaviours in soft matter, showing fascinating analogies with living polymers and polyelectrolytes. By only changing the concentration, the shear viscosity can vary by 7 orders of magnitude in the bulk when transitioning through the semidilute regime. In order to elucidate on the intrinsic shear viscosity profile at the interface in soft matter systems manifesting various concentration regimes and morphological transitions, we performed microrheology and adsorption experiments under a wide range of experimental conditions.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!