Amaphuzu avelele
● Isayensi yezinto eziphilayo yezingxube ze-surfactant engenayo i-sulfate ibonakala ngokuhlola.
● Imithelela ye-pH, ukwakheka nokugxila kwe-ionic kuphenywa ngendlela ehlelekile.
● I-CAPB:Isilinganiso sesisindo se-SMCT sika-1:0.5 sakha ubukhulu be-shear viscosity.
● Ukugxiliswa kukasawoti okubalulekile kuyadingeka ukuze kuzuzwe i-shear viscosity esiphezulu.
● Ubude bekhonta ye-Micellar obuqondiswe ku-DWS buhlobana kakhulu ne-shear viscosity.
Abstract
Ekuphishekeleni isizukulwane esilandelayo samapulatifomu e-surfactant angenayo i-sulfate, umsebenzi wamanje uhlinzeka ngophenyo lokuqala lwe-rheological oluhlelekile lwengxube ye-Cocamidopropyl Betaine (CAPB)-Sodium Methyl Cocoyl Taurate (SMCT) ehlukahlukene ekwakhiweni okuhlukahlukene, i-pH, namandla e-ionic. Izixazululo zamanzi ze-CAPB-SMCT (ingqikithi yokuhlushwa kwe-surfactant esebenzayo ye-8-12 wt. %) zalungiswa ngezilinganiso ezimbalwa zesisindo se-surfactant, zalungiswa ukuze zibe pHs 4.5 kanye ne-5.5, futhi zibhalwe nge-NaCl. Izilinganiso ze-shear eziqinile ne-oscillatory zilinganisela i-macroscopic shear viscosity, kuyilapho i-diffusing wave spectroscopy (DWS) microrheology inikeze imvamisa exazululwe i-viscoelastic moduli kanye nezikali zobude be-micellar. Ngaphansi kwezimo ezingenawo usawoti, ukwakheka kubonise i-Newtonian rheology ene-viscosities ye-shear ephezulu ku-CAPB:SMCT isisindo isilinganiso esingu-1:0.5, okubonisa ukuthuthukiswa kwebhuloho le-cationic-anionic headgroup. Ukwehlisa i-pH isuka ku-5.5 iye ku-4.5 kunikeza i-CAPB imali eningi ekhokhiswayo, ngaleyo ndlela kukhulisa ukuhlangana kwe-electrostatic nge-anionic SMCT ngokugcwele futhi kukhiqize amanethiwekhi aqinile e-micellar. Ukwengeza usawoti okuhlelekile kuguqule ukuhlehla kweqembu le-headgroup-headgroup, okuqhuba inguquko ye-morphological kusuka kuma-micelles ahlukene kuya kuma-aggregate amade, afana nezikelemu. Ama-viscosity we-Zero-shear abonise ubukhulu obuhlukile kuzilinganiso ezibucayi zikasawoti-to-surfactant (R), egqamisa ibhalansi eyinkimbinkimbi phakathi kokuhlolwa kwe-electrostatic double-layer kanye nokwelulwa kwe-micellar. I-DWS microrheology iqinisekise lokhu kubonwa kwe-macroscopic, yembula i-spectra ye-Maxwellian ehlukile ku-R ≥ 1, ehambisana nezindlela zokuphindaphinda ezilawulwa ngokuhlephuka. Ngokuphawulekayo, ubude bokubambelela kanye nokuphikelela buhlala bungaguquki ngamandla e-ionic, kuyilapho ubude bekhonta bubonisa ukuhlobana okuqinile ne-viscosity ye-zero-shear. Lokhu okutholakele kugcizelela indima ebalulekile ye-micellar elongation kanye ne-thermodynamic synergy ekulawuleni i-viscoelasticity ye-fluid, ihlinzeka ngohlaka lobunjiniyela bokusebenza okuphezulu kwe-sulfate-free surfactants ngokulawula okunembile kokuminyana kweshaji, ukwakheka, nezimo ze-ionic.
I-Graphical Abstrac
Isingeniso
Amasistimu we-aqueous binary surfactant ahlanganisa izinhlobo ezikhokhiswa ngokuphambene asetshenziswa kakhulu emikhakheni eminingi yezimboni, ehlanganisa izimonyo, ezemithi, amakhemikhali ezolimo, nezimboni ezilungisa ukudla. Ukwamukelwa okusabalele kwalezi zinhlelo kubangelwa ikakhulukazi ukusebenza kwazo okuphakeme kokuhlangana kobuso kanye ne-rheological, okuvumela ukusebenza okuthuthukisiwe ekubunjweni okuhlukahlukene. Ukuzihlanganisa kwe-synergistic kwama-surfactants anjalo ku-aggregate efana nezikelemu, ehilelekile kunikeza izici ze-macroscopic ezifundeka kakhulu, okuhlanganisa ukukhuphuka kwe-viscoelasticity kanye nokungezwani okuncishisiwe kobuso. Ikakhulukazi, izinhlanganisela ze-anionic kanye ne-zwitterionic surfactants zibonisa izithuthukisi ezihambisanayo emsebenzini ongaphezulu, i-viscosity, kanye nokuguquguquka kokungezwani kobuso. Lezi zindlela zokuziphatha zivela ekusebenzisaneni okuqinile kwe-electrostatic kanye ne-steric phakathi kwamaqembu ekhanda elipholile kanye nemisila ye-hydrophobic yama-surfactants, ngokuqhathaniswa nezinhlelo ze-surfactant eyodwa, lapho amandla e-electrostatic enyanyayo evame ukukhawulela ukulungiselelwa kokusebenza.
I-Cocamidopropyl betaine (CAPB; I-Smiles: CCCCCCCCCC(=O)NCCCN+ (C)CC([O−])=O) iyisisetshenziswa esisetshenziswa kakhulu se-amphoteric ekwenziweni kwezimonyo ngenxa yokusebenza kwayo kahle kokuhlanza kanye nezakhiwo zokupholisa izinwele. Imvelo ye-zwitterionic ye-CAPB inika amandla ukusebenzisana kwe-electrostatic nama-anionic surfactants, ithuthukisa ukuqina kwegwebu futhi ikhuthaze ukusebenza kokubunjwa okuphezulu. Eminyakeni engamashumi amahlanu edlule, izingxube ze-CAPB ezinama-surfactants asekelwe ku-sulfate, njenge-CAPB–sodium lauryl ether sulfate (SLES), seziyisisekelo emikhiqizweni yokunakekela umuntu. Kodwa-ke, naphezu kokuphumelela kwama-surfactants asekelwe ku-sulfate, ukukhathazeka mayelana namandla abo okucasula isikhumba kanye nokuba khona kwe-1,4-dioxane, i-byproduct yenqubo ye-ethoxylation, kubangele isithakazelo kwezinye izindlela ezingenayo i-sulfate. Amakhandidethi athembisayo afaka ama-surfactants asuselwa ku-amino-acid, njengama-taurates, ama-sarcosinates, nama-glutamates, abonisa ukuhambelana kwe-biocompatibility okuthuthukisiwe kanye nezakhiwo ezithambile [9]. Noma kunjalo, amaqembu amakhulu ngokuqhathaniswa amakhanda e-polar alezi zinketho ngokuvamile avimbela ukwakheka kwezakhiwo ze-micellar ezibambene kakhulu, okwenza kudingeke ukuthi kusetshenziswe iziguquli ze-rheological.
I-sodium methyl cocoyl taurate (SMCT; I-SMILES:
I-CCCCCCCCCCCC(=O)N(C)CCS(=O)(=O)O[Na]) iyisisetshenziswa se-anionic esakhiwe njengosawoti wesodium ngokuhlangana kwe-amide kwe-N-methyltaurine (2-methylaminoethanesulfonic acid) ngochungechunge lwe-acid ephuma kukhukhunathi. I-SMCT ineqembu le-taurine elixhunywe i-amide eduze neqembu elinamandla le-anionic sulfonate, elenza likwazi ukubola futhi lihambisane ne-pH yesikhumba, okuyibeka njengekhandidethi elithembisayo lokwakheka okungenayo i-sulfate . Ama-surfactants e-Taurate abonakala ngokuhlanzeka kwawo okunamandla, aqinile emanzini aqinile, ubumnene, nokuzinza okubanzi kwe-pH.
Imingcele ye-Rheological, ehlanganisa i-shear viscosity, i-viscoelastic moduli, kanye nengcindezi yesivuno, ibalulekile ekunqumeni ukuzinza, ukuthungwa, nokusebenza kwemikhiqizo esekelwe ku-surfactant. Isibonelo, ukuphakama kwe-shear viscosity kungathuthukisa ukugcinwa kwe-substrate, kuyilapho ukucindezeleka kwesivuno kulawula ukunamathela kokwakheka kwesikhumba noma izinwele ngemva kokufakwa kwesicelo. Lezi zimfanelo ze-rheological ze-macroscopic zishintshwa yizici eziningi, okuhlanganisa ukugxila kwe-surfactant, i-pH, izinga lokushisa, kanye nokuba khona kwezincibilikisi ezihlangene noma izithasiselo. Ama-surfactants afakwe ngokuphambene angabhekana noshintsho lwesakhiwo esincane, kusukela kuma-micelles ayindilinga nama-vesicles kuya ezigabeni zekristalu ewuketshezi, okubuye kube nomthelela omkhulu ku-rheology enkulu. Izingxube zezinto ezisebenza ngama-amphoteric kanye ne-anionic ngokuvamile zakha ama-micelles anjenge-wormlike (WLMs), athuthukisa kakhulu izici ze-viscoelastic. Ngakho-ke, ukuqonda ubudlelwano be-microstructure–property kubalulekile ekuthuthukiseni ukusebenza komkhiqizo.
Ucwaningo oluningi lokuhlola luphenye amasistimu kanambambili afanayo, njenge-CAPB-SLES, ukuze kucaciswe isisekelo sesakhiwo esincane sezakhiwo zabo. Ngokwesibonelo, uMitrinova et al. [13] usayizi we-micelle ohlotshaniswayo (irediyasi ye-hydrodynamic) ene-viscosity yesixazululo ku-CAPB-SLES-medium-chain-medium-chain co-surfactant izingxube zisebenzisa i-rheometry kanye ne-dynamic light scattering (DLS). I-rheometry yemishini inikeza ukuqonda ngokuvela kwe-microstructural yalezi zingxube futhi inganwetshwa yi-optical microrheology isebenzisa i-wave wave spectroscopy (DWS) enweba isizinda samafrikhwensi esifinyelelekayo, ithwebula amandla esikhashana esifushane ahambisana ikakhulukazi nezinqubo zokuphumula ze-WLM. Ku-DWS microrheology, isilinganiso esimaphakathi sokususwa kwesikwele se-colloidal probes eshumekiwe silandelelwa ngokuhamba kwesikhathi, okuvumela ukukhishwa kwemoduli eqondile ye-viscoelastic yendawo ezungezile kusetshenziswa ubudlelwano obujwayelekile be-Stokes-Einstein. Le nqubo idinga amavolumu amasampula amancane kuphela futhi ngaleyo ndlela inenzuzo ekutadisheni uketshezi oluyinkimbinkimbi olunokutholakala okulinganiselwe, isb. ukwakheka okusekelwe kumaprotheni . Ukuhlaziywa kwedatha ye-< Δr²(t)> kuwo wonke ama-spectra abanzi kusiza ukulinganiswa kwamapharamitha e-micellar njengosayizi we-mesh, ubude bokubopha, ubude bokuqhubeka, nobude bekhonta. U-Amin et al ubonise ukuthi izingxube ze-CAPB-SLES zivumelana nezibikezelo ezivela kumbono kaCates, okubonisa ukwanda okukhulu kwe-viscosity nosawoti ongeziwe kuze kube yilapho usawoti obalulekile, ngaphezu kwalokho i-viscosity yehla ngokushesha-impendulo evamile ezinhlelweni ze-WLM u-Xu no-Amin basebenzisa i-rheometry yomshini kanye ne-DWS ukuze bahlole ingxube ye-SLES-CAPB, i-CCB-rheological ukwakheka kwe-WLM okubambene, okuphinde kwaqinisekiswa amapharamitha esakhiwo esincane esithathwe ezilinganisweni ze-DWS. Ukwakhela phezu kwalezi zindlela, ucwaningo lwamanje luhlanganisa i-rheometry yemishini kanye ne-DWS microrheology ukuze kucace ukuthi ukuhlelwa kabusha kwesakhiwo esincane kuqhuba kanjani ukuziphatha kokugunda kwezingxube ze-CAPB-SMCT.
Ngenxa yesidingo esikhulayo sama-ejenti okuhlanza athambile futhi asimeme kakhudlwana, ukuhlolwa kwama-anionic surfactants angenayo i-sulfate kuye kwathuthuka naphezu kwezinselelo zokwakheka. Izakhiwo zamangqamuzana ezihlukile zezinhlelo ezingenayo i-sulfate zivame ukukhiqiza amaphrofayili e-rheological ahlukene, anzima amasu ajwayelekile okuthuthukisa i-viscosity njengokusebenzisa usawoti noma ukujiya kwe-polymeric. Ngokwesibonelo, u-Yorke et al. ihlole ezinye izindlela ezingezona i-sulfate ngokuphenya ngokuhlelekile izici zokugwaza kanye ne-rheological zezingxube ze-surfactant kanambambili ne-ternary ezihlanganisa i-alkyl olefin sulfonate (AOS), i-alkyl polyglucoside (APG), ne-lauryl hydroxysultaine. Isilinganiso esingu-1:1 se-AOS–sultaine sibonise izici zokushearna kanye nezici zegwebu ezifana ne-CAPB–SLES, okubonisa ukwakheka kwe-WLM. Rajput et al. [26] ihlole enye i-anionic surfactant engenayo i-sulfate, i-sodium cocoyl glycinate (SCGLY), eduze kwama-nonionic co-surfactants (i-cocamide diethanolamine ne-lauryl glucoside) nge-DLS, i-SANS, ne-rheometry. Nakuba i-SCGLY iyodwa yakha ama-micelles ayisiyingi ngokuyinhloko, ukungezwa kwe-co-surfactant kusize ukwakhiwa kwama-micellar morphologies ayinkimbinkimbi, akwazi ukuguquguquka okuqhutshwa yi-pH.
Naphezu kwalokhu kuthuthuka, uphenyo olumbalwa ngokuqhathaniswa oluqondise izici ze-rheological zezinhlelo ezisimeme ze-sulfate-free ezibandakanya i-CAPB nama-taurate. Lolu cwaningo luhlose ukugcwalisa lesi sikhala ngokuhlinzeka ngezimpawu zokuqala ze-rheological zesistimu kanambambili ye-CAPB–SMCT. Ngokushintsha ngokuhlelekile ukwakheka kwe-surfactant, i-pH, namandla e-ionic, sicacisa izici ezibusa i-shear viscosity kanye ne-viscoelasticity. Sisebenzisa i-rheometry yomshini kanye ne-DWS microrheology, silinganisela ukuhlelwa kabusha kwesakhiwo esincane esingaphansi kokuziphatha kokugunda kwezingxube ze-CAPB-SMCT. Lokhu okutholakele kucacisa ukusebenzisana phakathi kwe-pH, isilinganiso se-CAPB–SMCT, kanye namazinga e-ionic ekukhuthazeni noma ekuvimbeleni ukwakheka kwe-WLM, ngaleyo ndlela inikeze imininingwane engokoqobo ekuhlanganiseni amaphrofayili e-rheological wemikhiqizo esekelwe ku-surfactant esimeme yezinhlelo zokusebenza ezihlukene zezimboni.
Isikhathi sokuthumela: Aug-05-2025