Halayen halayen rheological na gaurayawan surfactant-free sulfate na cocamidopropyl betaine-sodium methyl cocoyl taurate a fadin abun da ke ciki, pH, da yanayin ionic

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Tsarukan surfactant na ruwa na binary wanda ya ƙunshi nau'ikan da aka caje daban-daban ana amfani da su sosai a sassan masana'antu da yawa, gami da kayan shafawa, magunguna, masana'antar agrochemicals, da masana'antar sarrafa abinci. Yaɗuwar karɓar waɗannan tsarin ana danganta shi ne da fifikon aikin su na tsaka-tsaki da na rheological, waɗanda ke ba da damar ingantacciyar aiki a cikin ƙira iri-iri. Haɗin kai na haɗin kai na irin waɗannan surfactants zuwa nau'in tsutsotsi, tarawa masu haɗaka suna ba da kaddarorin macroscopic sosai, gami da ƙãra danko da rage tashin hankali tsakanin fuska. Musamman, haɗe-haɗe na anionic da zwitterionic surfactants suna nuna haɓaka haɓakawa a cikin ayyukan sama, danko, da daidaita yanayin tashin hankali tsakanin fuska. Waɗannan halayen sun taso ne daga ingantacciyar hulɗar electrostatic da steric tsakanin ƙungiyoyin shugabannin polar da wutsiyoyi na hydrophobic na surfactants, suna bambanta da tsarin surfactant guda ɗaya, inda ƙarfin wutan lantarki mai tsauri sau da yawa yana iyakance haɓaka aiki.

Cocamidopropyl betaine (CAPB; SMILES: CCCCCCCCCC(=O)NCCCN+ (C)CC([O-])=O) wani nau'in amphoteric surfactant ne da ake amfani da shi sosai a cikin kayan kwaskwarima saboda sauƙin tsaftacewarsa da kaddarorin sanyaya gashi. Halin zwitterionic na CAPB yana ba da damar daidaitawa na lantarki tare da anionic surfactants, haɓaka kwanciyar hankali da haɓaka aikin ƙira. A cikin shekaru biyar da suka gabata, gaurayawan CAPB tare da sulfate na tushen surfactants, irin su CAPB-sodium lauryl ether sulfate (SLES), sun zama tushe a cikin samfuran kulawa na sirri. Koyaya, duk da tasirin surfactants na tushen sulfate, damuwa game da yuwuwar ɓacin rai na dermal da kasancewar 1,4-dioxane, samfuri na tsarin ethoxylation, sun haifar da sha'awar hanyoyin da ba su da sulfate. 'Yan takarar da ke da alƙawarin sun haɗa da tushen amino-acid surfactants, kamar taurates, sarcosinates, da glutamates, waɗanda ke nuna haɓakar haɓakar ƙwayoyin cuta da kaddarorin masu laushi [9]. Duk da haka, ƙananan ƙungiyoyin shugabannin pola na waɗannan hanyoyin sau da yawa suna hana samuwar sifofin micellar masu ruɗewa sosai, suna buƙatar yin amfani da na'urori masu gyara rheological.

Sodium methyl cocoyl taurate (SMCT; SMILES:
CCCCCCCCCCCC (= O) N (C) CCS (= O) (= O) O[Na]) wani nau'in surfactant ne wanda aka hada shi azaman gishiri na sodium ta hanyar haɗin haɗin gwiwa na N-methyltaurine (2-methylaminoethanesulfonic acid) tare da sarkar fatty acid mai kwakwa. SMCT yana da ƙungiyar taurine mai alaƙa da amide tare da ƙungiyar anionic sulfate mai ƙarfi, yana mai da shi biodegradable kuma ya dace da pH na fata, wanda ke sanya shi a matsayin ɗan takara mai ban sha'awa don ƙirar sulfate. Taurate surfactants ana siffanta su da ƙaƙƙarfan ƙaƙƙarfan ƙaƙƙarfan ƙaƙƙarfan ƙarfi, juriyar ruwa mai ƙarfi, tawali'u, da faɗin kwanciyar hankali na pH.

Ma'auni na rheological, gami da danko mai ƙarfi, viscoelastic moduli, da yawan damuwa, suna da mahimmanci a ƙayyadadden kwanciyar hankali, rubutu, da aikin samfuran tushen surfactant. Misali, girman dankon shear na iya inganta rikitaccen abu, yayin da yawan damuwa ke tafiyar da tsarin da aka yi ga fata ko gashi bayan aikace-aikacen. Wadannan sifofin rheological macroscopic ana daidaita su ta hanyar abubuwa masu yawa, gami da maida hankali na surfactant, pH, zazzabi, da kasancewar abubuwan haɗin gwiwa ko ƙari. Dabbobin da aka caje kishiyar su na iya fuskantar sauye-sauye na microstructural daban-daban, kama daga miceles mai siffar zobe da vesicles zuwa matakan kristal na ruwa, wanda, bi da bi, yana tasiri sosai ga ilimin rheology. Ganyayyaki na amphoteric da anionic surfactants sukan samar da elongated wormlike micelles (WLMs), wanda ke haɓaka kaddarorin viscoelastic sosai. Fahimtar ƙayyadaddun ƙayyadaddun ƙayyadaddun ƙayyadaddun ƙayyadaddun ƙayyadaddun abubuwa, don haka, yana da mahimmanci don haɓaka aikin samfur.

Yawancin gwaje-gwaje na gwaji sun bincika tsarin binary masu kamanceceniya, kamar CAPB-SLES, don fayyace tushen ƙananan kaddarorin su. Alal misali, Mitrinova et al. [13] Girman micelle mai alaƙa (radius hydrodynamic) tare da dankon bayani a cikin CAPB-SLES-matsakaicin sarkar co-surfactant gauraye ta hanyar amfani da rheometry da tarwatsa haske mai ƙarfi (DLS). rheometry na injina yana ba da haske game da juyin halittar microstructural na waɗannan gaurayawan kuma ana iya haɓaka ta ta hanyar microrheology na gani ta amfani da rarrabuwar raƙuman raƙuman ruwa (DWS) wanda ke faɗaɗa yankin mitar mai isa, yana ɗaukar matakan ɗan gajeren lokaci musamman masu dacewa da hanyoyin shakatawa na WLM. A cikin microrheology na DWS, ana bin diddigin madaidaicin murabba'in murɗaɗɗen binciken colloidal na tsawon lokaci, yana ba da damar haɓakar ƙirar viscoelastic na madaidaiciyar matsakaicin kewaye ta hanyar gamayya na Stokes-Einstein. Wannan dabarar tana buƙatar ƙididdige ƙididdiga kaɗan kawai kuma don haka yana da fa'ida don nazarin hadaddun ruwaye tare da iyakancewar kayan aiki, misali tsarin tushen furotin. Binciken <Δr²(t)> bayanai a cikin faffadan mitar mitoci yana sauƙaƙe ƙididdige sigogin micellar kamar girman raga, tsayin rikodi, tsayin tsayin daka, da tsayin kwane-kwane. Amin et al nuna cewa CAPB-SLES gaurayawan daidai da tsinkaya daga Cates 'ka'idar, nuna wani pronounced karuwa a danko tare da gishiri Bugu da kari har wani m gishiri maida hankali, bayan abin da danko saukad da precipitously-a hankula amsa a cikin WLM tsarin Xu da Amin aiki inji rheometry da DWS don bincikar SLES-CAPB-CCB-CCB a cikin SLES-CAPB-CCBangological gauraye a Maxaukacin amsa gauraye. samuwar, wanda aka ƙara inganta ta ta hanyar sigar microstructural da aka kwatanta daga ma'aunin DWS. Gina kan waɗannan hanyoyin, binciken na yanzu ya haɗu da rheometry na injiniya da kuma DWS microrheology don bayyana yadda tsarin sake tsara tsarin tsarin ke tafiyar da halayen juzu'i na gaurayawan CAPB-SMCT.

Dangane da karuwar buƙatu na wakilai masu sauƙi kuma masu ɗorewa, bincike na sulfate-free anionic surfactants ya sami ci gaba duk da ƙalubalen ƙira. Daban-daban tsarin gine-ginen ƙwayoyin cuta na tsarin marasa sulfate galibi suna haifar da mabambantan bayanan martaba na rheological, suna rikitarwa dabarun al'ada don haɓaka danko kamar ta gishiri ko kauri na polymeric. Alal misali, Yorke et al. binciko hanyoyin da ba sulfate ba ta hanyar bincikar tsarin kumfa da kaddarorin rheological na gaurayawan binary da ternary surfactant da ke nuna alkyl olefin sulfonate (AOS), alkyl polyglucoside (APG), da lauryl hydroxysultaine. Rabo na 1:1 na AOS-sultaine ya nuna halayen kumfa mai kauri da sifofi daidai da CAPB-SLES, yana nuna samuwar WLM. Rajput et al. [26] kimanta wani surfactant anionic sulfate-free, sodium cocoyl glycinate (SCGLY), tare da nonionic co-surfactants (cocamide diethanolamine da lauryl glucoside) ta DLS, SANS, da rheometry. Ko da yake SCGLY shi kaɗai ya samar da miceles masu siffar zobe, ƙari na haɗin gwiwa ya ba da damar gina ƙarin ƙayyadaddun ƙwayoyin halittar micellar, wanda ya dace da ƙirar pH.

Duk da waɗannan ci gaban, kwatankwacin ƴan bincike sun yi niyya ga kaddarorin rheological na tsarin da ba shi da sulfate mai dorewa wanda ya ƙunshi CAPB da taurates. Wannan binciken yana nufin cike wannan rata ta hanyar samar da ɗaya daga cikin sifofin rheological na farko na tsarin binary CAPB-SMCT. Ta hanyar sauye-sauyen tsarin surfactant na tsari, pH, da ƙarfin ionic, muna haɓaka abubuwan da ke tafiyar da danko da danko. Yin amfani da rheometry na injiniya da microrheology na DWS, muna ƙididdige gyare-gyaren ƙayyadaddun ƙayyadaddun ƙayyadaddun ƙayyadaddun halayen haɓakar CAPB-SMCT. Waɗannan binciken suna haɓaka hulɗar tsakanin pH, CAPB-SMCT rabo, da matakan ionic don haɓaka ko hana samuwar WLM, ta haka ne ke ba da haske mai amfani don daidaita bayanan martaba na samfuran tushen surfactant mai dorewa don aikace-aikacen masana'antu iri-iri.