Wormlike Micelles in Mixed Amino Acid‐Based Anionic Surfactant and Zwitterionic Surfactant Systems

Abstract

The formation of wormlike micelles in aqueous solutions of an amino acid‐based surfactant, sodium lauroyl sarcosinate (LS) and a zwitterionic surfactant, cocamidopropyl betaine (CAPB) has been investigated. Holding the total concentration of LS and CAPB constant at 12 wt%, the synergistic effects of mass ratio of CAPB and LS and pH of the micelle solution on rheological behaviors of CAPB/LS micelles were studied. The viscosity of CAPB/LS micelle systems with a mass ratio from 4:8 to 9:3 increases to maximum values and then decreases as pH increases from 4.0 to 5.6. The maximum viscosity of the transparent CAPB/LS micelle solution is nearly 5500 mPa·s with a mass ratio of CAPB/LS = 8:4 at pH 5.10. It is suggested that the proper pH for CAPB and LS to form wormlike micelles should be close to the isoelectric point of the CAPB/LS solution. The results of thixotropy measurements show that the appropriate mass ratio of CAPB/LS can improve the stability of the network structure of wormlike micelles. In addition, viscosity curves of CAPB/LS wormlike micelles follow a nonlinear co‐rotational Jeffreys model, and the linear viscoelasticity of CAPB/LS wormlike micelles can be described by a linear viscoelastic Jeffreys model. The network of wormlike micelles is confirmed by Cryo‐TEM images.

Impact of wormlike micelles on nano and macroscopic structure of TEMPO-oxidized cellulose nanofibril hydrogels

“…13,43,45,46 They are expected to be ellipsoidal objects with half axes of 13 Â 23 Â 23 Å, in solutions with salt concentrations smaller than 0.5 M NaCl. 43 For the three other surfactants studied in this work, CAPB, 28,31,[47][48][49] CAPOx, and SLS, 47,50 the information available is more limited. We conducted SANS experiments at three different concentrations above the critical micellar concentration (CMC) for each of these surfactants.…”

“…We studied the influence of surfactant mixtures on the gelation behaviour of OCNFs under saline conditions. Three mixtures, offering three different micellar morphologies were studied: cocamidopropyl betaine (CAPB)/sodium dodecyl sulphate (SDS), cocamidopropylamine oxide 30 (CAPOx)/SDS and CAPB/sodium lauroyl sarcosinate 31 (SLS). Under saline conditions, CAPB/SDS mixtures will form long rodlike micelles and, under the right conditions, 28 generate an entangled network of wormlike micelles (WLMs), while CAPOx/ SDS formed shorter cylinders and CAPB/SLS formed spherical micelles.…”

Synergistic Interaction and Aggregation Behavior in a Mixture of a Tripolar Zwitterionic Surfactant and an Anionic Surfactant

“…Thus, surfactant mixtures are commonly used in industrial applications and in pharmaceutical and medicinal formulations for the purpose of solubilization, suspension, and dispersion (Moulik et al, ; Sharma et al, ). In recent years, considerable research has been carried out on different combinations of mixed surfactant systems, including nonionic/nonionic (Ádám Juhász et al, ; Thomas et al, ), anionic/nonionic (Mahajan and Nandni, ), cationic/anionic (Schubert et al, ; Tian et al, ; Xu et al, ), cationic/cationic (Padasala et al, ; Tian et al, ), zwitterionic/anionic (Lu et al, ; Maneedaeng and Flood, ; Zhai et al, ), and zwitterionic/cationic (Abdel‐Rahem, ) surfactant systems. Normally, a stronger interaction between two surfactants leads to greater synergism in mixed surfactant systems (Holland and Rubingh, ).…”

Properties and applications of amphoteric surfactant: A concise review

“…The irritating effect on the skin was greatly decreased by amphoteric cocamidopropyl betaine (CAPB) as compared to anionic SLES (Sodium Laureth Sulfate) and SDS (Sodium Lauryl Sulfate) (Förster et al, 2000). The aqueous mixture of CAPB and lauroyl sarcosinate (LS) in suitable pH conditions could form viscoelastic worm like micelles without the use of the polymer as a thickener, and it had been extremely moderate on human skin to allow this compound to be added to the cosmetic industry (Lu et al, 2015). Recently, Zieba et al have synthesized some new betaines and sulfobetaines, which demonstrate strong efficiency in washing (Zieba et al, 2019).…”