Qhov tseem ceeb
● Rheology ntawm binary sulfate-dawb surfactant sib tov yog yam ntxwv xyaum ua.
● Cov teebmeem ntawm pH, muaj pes tsawg leeg thiab ionic concentration yog soj ntsuam raws li systematically.
● CAPB: SMCT surfactant huab hwm coj piv ntawm 1: 0.5 tsim qhov siab tshaj plaws shear viscosity.
● Qhov tseem ceeb ntsev concentration yuav tsum ua kom tiav shear viscosity siab tshaj plaws.
● Micellar contour ntev inferred los ntawm DWS correlates heev nrog shear viscosity.
Abstract
Hauv kev nrhiav cov txheej txheem tom ntej ntawm sulfate-dawb surfactant platforms, txoj haujlwm tam sim no muab ib qho ntawm thawj qhov kev tshawb xyuas rheological ntawm aqueous Cocamidopropyl Betaine (CAPB)-Sodium Methyl Cocoyl Taurate (SMCT) sib tov thoob plaws ntau yam sib txawv, pH, thiab ionic zog. CAPB-SMCT aqueous daws (tag nrho cov active surfactant concentration ntawm 8-12 wt. %) tau npaj ntawm ob peb surfactant qhov hnyav piv, hloov mus rau pHs 4.5 thiab 5.5, thiab titrated nrog NaCl. Kev ntsuas tsis tu ncua thiab oscillatory shear ntsuas kom muaj nuj nqis macroscopic shear viscosity, thaum diffusing yoj spectroscopy (DWS) microrheology muab zaus daws viscoelastic moduli thiab cov yam ntxwv micellar length scales. Nyob rau hauv cov dej tsis muaj ntsev, cov formulations nthuav tawm Newtonian rheology nrog qhov siab tshaj plaws shear viscosities ntawm CAPB: SMCT qhov hnyav piv ntawm 1: 0.5, qhia txog kev txhim kho cationic-anionic headgroup bridging. Txo cov pH ntawm 5.5 mus rau 4.5 conferred net zoo nqi ntawm CAPB, yog li amplifying electrostatic complexation nrog rau tag nrho cov anionic SMCT thiab generating robust micellar tes hauj lwm. Systematic ntsev ntxiv modulated headgroup-headgroup repulsions, tsav morphological evolution los ntawm discrete micelles mus rau elongated, wormlike aggregates. Zero-shear viscosities nthuav tawm qhov sib txawv maxima ntawm qhov tseem ceeb ntsev-rau-surfactant ratios (R), qhia txog qhov sib npaug sib npaug ntawm electrostatic ob txheej tshuaj ntsuam xyuas thiab micellar elongation. DWS microrheology corroborated cov kev soj ntsuam macroscopic, unveiling txawv Maxwellian spectra ntawm R ≥ 1, zoo ib yam nrog reptation-dominated breakage-recombination mechanisms. Qhov tseem ceeb, qhov entanglement thiab persistence lengths tseem tsis sib xws nrog lub zog ionic, thaum contour ntev pom muaj kev sib raug zoo nrog xoom-shear viscosity. Cov kev tshawb pom no hais txog lub luag haujlwm tseem ceeb ntawm micellar elongation thiab thermodynamic synergy hauv kev tswj cov kua viscoelasticity, muab lub hauv paus rau kev ua haujlwm siab ntawm sulfate-dawb surfactants los ntawm kev tswj cov nqi ceev, muaj pes tsawg leeg, thiab ionic tej yam kev mob.
Graphical Absrac
Taw qhia
Aqueous binary surfactant systems suav nrog cov tsiaj sib txawv tau siv dav hauv ntau qhov chaw lag luam, suav nrog tshuaj pleev ib ce, tshuaj, agrochemicals, thiab kev lag luam ua zaub mov. Kev siv dav dav ntawm cov tshuab no feem ntau yog los ntawm lawv cov kev sib txuas lus zoo tshaj plaws thiab kev ua haujlwm rheological, uas ua kom muaj kev ua tau zoo hauv ntau hom kev tsim. Lub synergistic nws tus kheej sib sau ua ke ntawm cov surfactants rau hauv wormlike, entangled aggregates imparts heev tunable macroscopic zog, nrog rau nce viscoelasticity thiab txo interfacial nro. Hauv particular, kev sib txuas ntawm anionic thiab zwitterionic surfactants muaj kev sib koom ua ke hauv kev ua haujlwm saum npoo av, viscosity, thiab kev hloov pauv ntawm kev sib tshuam. Cov kev coj cwj pwm no tshwm sim los ntawm kev sib zog ntawm electrostatic thiab steric kev sib cuam tshuam ntawm cov pawg polar taub hau thiab hydrophobic tails ntawm surfactants, sib piv nrog ib leeg-surfactant systems, qhov twg repulsive electrostatic rog feem ntau txwv kev ua tau zoo.
Cocamidopropyl betaine (CAPB; SMILES: CCCCCCCCCCCC(=O)NCCCN+ (C)CC([O−])=O) yog siv dav siv amphoteric surfactant hauv cov tshuaj pleev ib ce vim nws cov tshuaj ntxuav me me thiab cov plaub hau txias. Lub zwitterionic xwm ntawm CAPB enables electrostatic synergy nrog anionic surfactants, txhim khu ua npuas ncauj stability thiab txhawb superior formulation kev ua tau zoo. Tshaj li tsib xyoos dhau los, CAPB sib xyaw nrog sulfate-based surfactants, xws li CAPB-sodium lauryl ether sulfate (SLES), tau dhau los ua lub hauv paus hauv cov khoom tu tus kheej. Txawm li cas los xij, txawm tias muaj txiaj ntsig zoo ntawm sulfate-based surfactants, kev txhawj xeeb txog lawv qhov kev ua kom khaus khaus khaus thiab muaj 1,4-dioxane, uas yog cov khoom lag luam ntawm cov txheej txheem ethoxylation, tau ua rau muaj kev txaus siab rau kev xaiv tsis muaj sulfate. Cov neeg sib tw muaj txiaj ntsig suav nrog cov amino-acid-based surfactants, xws li taurates, sarcosinates, thiab glutamates, uas nthuav tawm kev txhim kho biocompatibility thiab cov khoom me me [9]. Txawm li cas los xij, cov pawg loj ntawm lub taub hau ntawm cov kev xaiv no feem ntau cuam tshuam rau kev tsim cov qauv micellar heev, yuav tsum tau siv cov kev hloov kho rheological.
Sodium methyl cocoyl taurate (SMCT; SMILES:
CCCCCCCCCCCC(=O)N(C)CCS(=O)(=O)O[Na]) yog ib qho anionic surfactant synthesized li sodium ntsev ntawm amide coupling ntawm N-methyltaurine (2-methylaminoethanesulfonic acid) nrog cov txiv maj phaub-derived fatty acid saw. SMCT muaj ib qho amide-linked taurine headgroup nrog rau cov pab pawg neeg anionic sulfonate, ua rau nws biodegradable thiab sib haum nrog pH ntawm daim tawv nqaij, uas tso cai rau nws los ua ib tus neeg sib tw rau cov tshuaj sulfate-dawb formulations. Taurate surfactants yog tus cwj pwm los ntawm lawv cov muaj zog detergency, tawv-dej resilience, me ntsis, thiab dav pH stability.
Rheological tsis, suav nrog shear viscosity, viscoelastic moduli, thiab yield stress, yog ib qho tseem ceeb rau kev txiav txim siab stability, kev ntxhib los mos, thiab kev ua tau zoo ntawm surfactant-based khoom. Piv txwv li, elevated shear viscosity tuaj yeem txhim kho substrate tuav, thaum lub zog tawm los tswj cov qauv kev ua raws li daim tawv nqaij lossis plaub hau tom qab daim ntawv thov. Cov macroscopic rheological cwj pwm no yog modulated los ntawm ntau yam, nrog rau surfactant concentration, pH, kub, thiab muaj cov co-solvents los yog additives. Tus nqi surfactants tuaj yeem ua rau muaj ntau yam kev hloov pauv ntawm microstructural, xws li cov micelles kheej kheej thiab cov hlwv mus rau cov kua crystalline theem, uas, nyob rau hauv lem, profoundly cuam tshuam rau tej rheology. Kev sib xyaw ntawm amphoteric thiab anionic surfactants feem ntau tsim elongated wormlike micelles (WLMs), uas txhim kho viscoelastic zog. Kev nkag siab txog microstructure-cov khoom sib raug zoo yog, yog li ntawd, tseem ceeb heev rau kev ua kom zoo ntawm cov khoom lag luam.
Ntau cov kev tshawb fawb sim tau tshawb xyuas cov tshuab binary zoo sib xws, xws li CAPB-SLES, los qhia txog lub hauv paus microstructural ntawm lawv cov khoom. Piv txwv li, Mitrinova et al. [13] correlated micelle loj (hydrodynamic radius) nrog cov tshuaj viscosity hauv CAPB-SLES-medium-chain co-surfactant sib tov siv rheometry thiab dynamic light scattering (DLS). Mechanical rheometry muab kev pom rau hauv microstructural evolution ntawm cov kev sib tov thiab tuaj yeem ua kom zoo dua los ntawm kev kho qhov muag microrheology siv diffusing yoj spectroscopy (DWS) uas txuas rau qhov siv tau ntau zaus, ntes cov sij hawm luv luv tshwj xeeb tshaj yog cuam tshuam rau WLM so cov txheej txheem. Nyob rau hauv DWS microrheology, lub ntsiab lus square hloov chaw ntawm embedded colloidal probes yog taug qab nyob rau lub sij hawm, ua kom lub extraction ntawm linear viscoelastic moduli ntawm ib puag ncig nruab nrab ntawm lub generalized Stokes-Einstein kev sib raug zoo. Cov txheej txheem no tsuas yog yuav tsum muaj cov qauv me me xwb thiab yog li muaj txiaj ntsig zoo rau kev kawm cov kua dej sib xyaw nrog cov khoom siv tsawg, xws li cov qauv tsim cov protein. Kev soj ntsuam ntawm < Δr²(t)> cov ntaub ntawv hla dav zaus spectra txhawb kev kwv yees ntawm micellar tsis xws li mesh loj, entanglement length, persistence length, thiab contour ntev. Amin thiab al tau qhia tias CAPB-SLES cov khoom sib xyaw ua raws li kev kwv yees los ntawm Cates' txoj kev xav, uas qhia tau hais tias muaj kev nce ntxiv hauv viscosity nrog ntsev ntxiv kom txog rau thaum muaj ntsev tseem ceeb, dhau qhov uas viscosity drops precipitously-ib qho lus teb nyob rau hauv WLM systems Xu thiab Amin ua hauj lwm mechanical rheometry, DWSB toCA. Maxwellian rheological teb qhia tau hais tias entangled WLM tsim, uas tau ntxiv corroborated los ntawm microstructural tsis inferred los ntawm DWS ntsuas. Ua raws li cov txheej txheem no, txoj kev tshawb fawb tam sim no sib koom ua ke cov tshuab rheometry thiab DWS microrheology los piav qhia tias cov txheej txheem microstructural reorganizations tsav tus cwj pwm ntawm CAPB-SMCT li cas.
Nyob rau hauv lub teeb ntawm escalating thov rau softer thiab ntau sustainable cleansing agents, kev tshawb nrhiav ntawm sulfate-dawb anionic surfactants tau txais lub zog txawm tias muaj teeb meem kev tsim. Cov txheej txheem molecular txawv ntawm cov tshuab tsis muaj sulfate feem ntau ua rau muaj qhov sib txawv ntawm cov rheological profiles, ua rau nyuaj rau cov tswv yim zoo rau kev txhim kho viscosity xws li ntsev los yog polymeric thickening. Piv txwv li, Yorke et al. tshawb nrhiav cov kev xaiv uas tsis yog-sulfate los ntawm kev tshawb xyuas cov foaming thiab rheological zog ntawm binary thiab ternary surfactant mixs featuring alkyl olefin sulfonate (AOS), alkyl polyglucoside (APG), thiab lauryl hydroxysultaine. A 1: 1 piv ntawm AOS-sultaine pom shear-thinning thiab ua npuas ncauj yam ntxwv zoo li CAPB-SLES, qhia WLM tsim. Rajput et al. [26] soj ntsuam lwm yam sulfate-free anionic surfactant, sodium cocoyl glycinate (SCGLY), nrog rau cov nonionic co-surfactants (cocamide diethanolamine thiab lauryl glucoside) los ntawm DLS, SANS, thiab rheometry. Txawm hais tias SCGLY ib leeg tsim cov micelles kheej kheej feem ntau, co-surfactant ntxiv tau ua rau kev tsim kho ntawm micellar morphologies intricate ntau, amenable rau pH-driven modulation.
Txawm hais tias qhov kev nce qib no, kev sib piv ob peb qhov kev tshawb fawb tau tsom rau cov khoom siv rheological ntawm cov tshuab tsis muaj sulfate-dawb uas koom nrog CAPB thiab taurates. Txoj kev tshawb no tsom mus ua kom tiav qhov sib txawv no los ntawm kev muab ib qho ntawm thawj qhov systematic rheological yam ntxwv ntawm CAPB-SMCT binary system. Los ntawm kev sib txawv ntawm cov surfactant muaj pes tsawg leeg, pH, thiab ionic zog, peb elucidate cov yam ntxwv tswj shear viscosity thiab viscoelasticity. Siv cov tshuab rheometry thiab DWS microrheology, peb suav cov microstructural reorganizations hauv qab lub shear cwj pwm ntawm CAPB-SMCT sib tov. Cov kev tshawb pom no qhia txog kev sib cuam tshuam ntawm pH, CAPB-SMCT piv, thiab qib ionic hauv kev txhawb lossis inhibiting WLM tsim, yog li muab cov tswv yim pom zoo rau kev txiav cov rheological profiles ntawm cov khoom lag luam surfactant rau kev siv ntau yam.
Post lub sij hawm: Aug-05-2025