Izakhiwo ze-Cationic Cellulose Ether Solution

Izakhiwo zesisombululo esincibilikisiwe se-high-charge-density cationic cellulose ether (KG-30M) ngamavelu e-pH ahlukene ahlolisiswa ngethuluzi lokuhlakaza le-laser, kusukela kurediyasi ye-hydrodynamic (Rh) kuma-engeli ahlukene, kanye nempande isho irediyasi yesikwele yokuzungezisa. Rg Isilinganiso ku-Rh sichaza ukuthi umumo wayo awujwayelekile kodwa usondelene nendingilizi. Khona-ke, ngosizo lwe-rheometer, izixazululo ezintathu ezigxiliwe ze-cationic cellulose ethers ezinobunzima obuhlukene bokushaja zacwaningwa ngokuningiliziwe, kanye nomthelela wokugxila, inani le-pH kanye nomthamo wayo wezindleko ezicini zayo ze-rheological. Njengoba ukugxila kuyanda, i-exponent ka-Newton yaqala yehla futhi yabe seyehla. Ukushintshashintshashintsha noma ukuphindaphinda kwenzeka, futhi ukuziphatha kwe-thixotropic kwenzeka ku-3% (ingxenyana yobuningi). Ukuminyana kokushaja okumaphakathi kunenzuzo ukuthola i-viscosity ephezulu ye-zero-shear, futhi i-pH inomthelela omncane ku-viscosity yayo.

Amagama angukhiye:i-cationic cellulose ether; i-morphology; i-viscosity ye-shear zero; i-rheology

Okuphuma ku-cellulose kanye nama-polymers awo asebenzayo ashintshiwe asetshenziswe kabanzi emkhakheni wemikhiqizo ye-physiological and sanitary, amakhemikhali e-petrochemicals, imithi, ukudla, imikhiqizo yokunakekelwa komuntu siqu, ukupakishwa, njll. I-cationic cellulose ether encibilikayo emanzini (CCE) ingenxa yokuqina kwayo okuqinile. ikhono, isetshenziswa kabanzi kumakhemikhali wansuku zonke, ikakhulukazi ama-shampoos, futhi ingathuthukisa ukuhambisana kwezinwele ngemva kokugeza izinwele. Ngesikhathi esifanayo, ngenxa yokuhambisana kwayo okuhle, ingasetshenziswa kuma-shampoos amabili-in-one kanye nawo wonke-in-one. Ibuye ibe nethuba elihle lokufaka isicelo futhi idonse ukunaka kwamazwe ahlukahlukene. Kubikwe ezincwadini ukuthi izixazululo ze-cellulose derivative zibonisa ukuziphatha okufana ne-Newtonian fluid, i-pseudoplastic fluid, i-thixotropic fluid kanye ne-viscoelastic fluid kanye nokwanda kokugxila, kodwa i-morphology, i-rheology kanye nezici ezithonya ze-cationic cellulose ether ku-aqueous solution Zimbalwa. imibiko yocwaningo. Leli phepha ligxile ekuziphatheni kwe-rheological kwe-quaternary ammonium modified cellulose aqueous solution, ukuze kunikezwe ireferensi yokusetshenziswa okungokoqobo.

1. Ingxenye yokuhlola

1.1 Izinto ezisetshenziswayo

I-Cationic cellulose ether (KG-30M, JR-30M, LR-30M); Umkhiqizo we-Canada Dow Chemical Company, ohlinzekwe yi-Procter & Gamble Company Kobe R&D Center e-Japan, ukalwe nge-Vario EL elemental analyzer (German Elemental Company), isampula Okuqukethwe kwe-nitrogen ngu-2.7%, 1.8%, 1.0% ngokulandelanayo (i-charge density 1.9 Meq/g, 1.25 Meq/g, 0.7 Meq/g ngokulandelanayo), futhi ihlolwe yi-German ALV-5000E laser light Scattering instrument (LLS) ikalwe isisindo sayo esimaphakathi nesisindo se-molecular cishe ngu-1.64×106g/mol.

1.2 Ukulungiswa kwesixazululo

Isampula yahlanzwa ngokuhlunga, i-dialysis kanye nokomisa iqhwa. Kala uchungechunge lwamasampuli amathathu omthamo ngokulandelanayo, bese wengeza isisombululo sebhafa esijwayelekile nge-pH 4.00, 6.86, 9.18 ukuze ulungiselele ukugxilisa ingqondo okudingekile. Ukuze kuqinisekiswe ukuthi amasampula ahlakazwe ngokugcwele, zonke izixazululo zesampula zafakwa kusivusi kazibuthe amahora angama-48 ngaphambi kokuhlolwa.

1.3 Isilinganiso sokuhlakazeka okulula

Sebenzisa i-LLS ukuze ulinganise isisindo se-molecular weight-average yesampula kusixazululo esimanzi, irediyasi ye-hydrodynamic kanye nempande isho irediyasi yesikwele yokuzungezisa lapho i-coefficient ye-Villi yesibili nama-engeli ahlukene,), bese ubeka ukuthi le cationic cellulose ether iku isisombululo se-aqueous ngesimo saso sesilinganiso.

1.4 Isilinganiso se-viscosity kanye nophenyo lwe-rheological

Isixazululo se-CCE esigxilisiwe sacwaningwa yi-rheometer ye-Brookfield RVDV-III+, futhi kwaphenywa nomthelela wokugxilisa ingqondo, ukuminyana kokushaja kanye nenani le-pH ezimpahleni ze-rheological ezifana nesampula ye-viscosity yaphenywa. Ekugxilweni okuphezulu, kuyadingeka ukuphenya i-thixotropy yayo.

2. Imiphumela kanye nengxoxo

2.1 Ucwaningo Ngokuhlakazeka Kokukhanya

Ngenxa yesakhiwo sayo esikhethekile samangqamuzana, kunzima ukuba khona ngesimo se-molecule eyodwa ngisho ne-solvent enhle, kodwa ngesimo sama-micelles athile azinzile, amaqoqo noma izinhlangano.

Lapho isisombululo se-aqueous dilute (~o.1%) se-CCE sibonwa ngesibonakhulu esihlukanisayo, ngaphansi kwesizinda senkambu ye-orthogonal yesiphambano esimnyama, amabala agqamile "inkanyezi" namabha agqamile avela. Ibuye ibonakale ngokuhlakazeka kokukhanya, irediyasi eguquguqukayo ye-hydrodynamic ku-pH nama-engeli ahlukene, impande yerediyasi yesikwele yokuzungezisa kanye ne-coefficient ye-Villi yesibili etholwe kumdwebo we-Berry afakwe ku-Tab. 1. Igrafu yokusabalalisa yomsebenzi werediyasi ye-hydrodynamic etholwe ekuhlanganiseni okungu-10-5 ngokuyinhloko isiqongo esisodwa, kodwa ukusatshalaliswa kubanzi kakhulu (Umfanekiso 1), okubonisa ukuthi kukhona izinhlangano zamangqamuzana nama-aggregate amakhulu ohlelweni. ; Kukhona izinguquko, futhi amanani e-Rg/Rb azungeze u-0.775, okubonisa ukuthi ukwakheka kwe-CCE esixazululweni kuseduze nokuyisiyingi, kodwa akujwayelekile ngokwanele. Umthelela we-pH ku-Rb ne-Rg awubonakali. I-counterion kusixazululo se-buffer isebenzisana ne-CCE ukuvikela ukushaja ochungechungeni lwayo oluseceleni futhi yenze inciphe, kodwa umehluko uyahlukahluka ngohlobo lokubala. Isilinganiso sokuhlakazeka okulula kwama-polymers ashajiwe sisengozini yokusebenzisana kwamandla ebanga elide kanye nokuphazamiseka kwangaphandle, ngakho-ke kukhona amaphutha athile kanye nemikhawulo ekucacisweni kwezinhlamvu ze-LLS. Uma ingxenye enkulu ye-mass ingaphezu kuka-0.02%, kuneziqongo eziphindwe kabili ezingenakuhlukaniswa noma iziqongo eziningi kumdwebo wokusabalalisa we-Rh. Njengoba ukugxila kukhula, i-Rh nayo iyanda, okubonisa ukuthi ama-macromolecules amaningi ahlotshaniswa noma ahlanganiswe. Lapho uCao et al. wasebenzisa ukusabalalisa ukukhanya ukuze atadishe i-copolymer ye-carboxymethyl cellulose kanye nama-macromers asebenza phezulu, kwakukhona futhi iziqongo eziphindwe kabili ezingenakuhlukaniswa, enye yazo eyayiphakathi kuka-30nm no-100nm, emele ukwakheka kwama-micelles ezingeni lamangqamuzana, kanti enye I-peak Rh iqhathaniswa. enkulu, ethathwa njengenhlanganisela, efana nemiphumela enqunywe kuleli phepha.

2.2 Ucwaningo ngokuziphatha kwe-rheological

2.2.1 Umthelela wokugxilisa ingqondo:Linganisa i-viscosity ebonakalayo yezixazululo ze-KG-30M ngokugxila okuhlukene ngamanani ahlukene okugunda, futhi ngokohlobo lwe-logarithmic lwe-equation yomthetho wamandla ehlongozwa ngu-Ostwald-Dewaele, lapho ingxenye enkulu ingeqi ku-0.7%, kanye nochungechunge lwemigqa eqondile. ngama-coefficients omugqa wokuhlanganisa amakhulu kuno-0.99 atholiwe. Futhi njengoba ukugxila kukhula, inani le-eksponenti ka-Newton n liyehla (konke lingaphansi kuka-1), okubonisa uketshezi olusobala lwe-pseudoplastic. Eqhutshwa amandla e-shear, amaketanga e-macromolecular aqala ukugoqa futhi abheke, ngakho i-viscosity iyancipha. Uma ingxenyenamba enkulu ingaphezu kuka-0.7%, i-coefficient yomugqa womugqa womugqa oqondile etholakalayo iyancipha (cishe ngo-0.98), futhi n iqala ukuguquguquka noma ikhuphuke ngokwanda kokugxila; lapho ingxenye enkulu ifinyelela ku-3% (Fig. 2), ithebula I-viscosity ebonakalayo iqala ukwanda bese iyancipha ngokunyuka kwezinga le-shear. Lolu chungechunge lwezimo luhlukile emibikweni yezinye izixazululo ze-anionic ne-cationic polymer. Inani elingu-n liyakhuphuka, okungukuthi, impahla okungeyona eyaseNewtonian yenziwe buthaka; I-Newtonian fluid iyi-viscous liquid, futhi i-intermolecular slippage ivela ngaphansi kwesenzo sokucindezeleka kwe-shear, futhi ayikwazi ukubuyiselwa; I-non-Newtonian fluid iqukethe ingxenye enwebekayo ebuyisekayo kanye nengxenye ye-viscous engatholakali. Ngaphansi kwesenzo sokucindezeleka kwe-shear, ukushelela okungenakuguqulwa phakathi kwama-molecule kwenzeka, futhi ngesikhathi esifanayo, ngenxa yokuthi ama-macromolecules anwetshiwe futhi aqondiswe nge-shear, kwakheka ingxenye enwebekayo ebuyiselwayo. Lapho amandla angaphandle esuswa, ama-macromolecules athambekele ekubuyeleni efomini eligoqiwe lokuqala, ngakho Inani lika-n liyakhuphuka. Ukugxila kuyaqhubeka nokwanda ukuze kwakhiwe isakhiwo senethiwekhi. Lapho ukucindezeleka kwe-shear kukuncane, ngeke kubhujiswe, futhi i-deformation elastic kuphela izokwenzeka. Ngalesi sikhathi, i-elasticity izothuthukiswa ngokuqhathaniswa, i-viscosity izoba buthakathaka, futhi inani le-n lizokwehla; kuyilapho ingcindezi yokugunda ikhula kancane kancane phakathi nenqubo yokulinganisa, ngakho n Inani liyashintshashintsha. Lapho ingxenyenamba enkulu ifinyelela ku-3%, i-viscosity ebonakalayo iqala ukwanda bese iyancipha, ngoba i-shear encane ikhuthaza ukungqubuzana kwama-macromolecules ukwakha ama-aggregates amakhulu, ngakho-ke i-viscosity iphakama, futhi ukucindezeleka kwe-shear kuyaqhubeka nokuphula ama-aggregates. , i-viscosity izokwehla futhi.

Ophenyweni lwe-thixotropy, setha isivinini (r/min) ukuze ufinyelele ku-y oyifunayo, ukhuphule isivinini ngezikhathi ezithile kuze kube yilapho sifinyelela inani elibekiwe, bese wehla ngokushesha ukusuka kusivinini esikhulu ubuyele enanini lokuqala ukuze uthole okuhambisanayo. Ukucindezeleka kwe-shear, ubuhlobo bawo nesilinganiso sokugunda kuboniswa ku-Fig. 3. Uma ingxenye enkulu ye-mass ingaphansi kuka-2.5%, ijika elikhuphukayo kanye ne-curve ephansi idlula ngokuphelele, kodwa uma ingxenye enkulu ingu-3%, imigqa emibili ayikho. ukugqagqana okude, futhi umugqa obheke phansi usale ngemuva, okubonisa i-thixotropy.

Ukuncika kwesikhathi kokucindezeleka kwe-shear kwaziwa ngokuthi ukumelana ne-rheological. Ukumelana ne-Rheological kuwukuziphatha okuyisici koketshezi lwe-viscoelastic noketshezi olunezakhiwo ze-thixotropic. Kutholakala ukuthi u-y omkhulu usengxenyeni efanayo yenqwaba, i-r esheshayo ifinyelela ukulingana, futhi ukuncika kwesikhathi kuncane; engxenyeni encane yesisindo (<2%), i-CCE ayibonisi ukumelana ne-rheological. Lapho ingxenye enkulu ikhula ibe ngu-2.5%, ibonisa ukuncika kwesikhathi esiqinile (Fig. 4), futhi kuthatha imizuzu engaba ngu-10 ukufinyelela ukulingana, kuyilapho ku-3.0%, isikhathi sokulinganisa sithatha imizuzu engu-50. I-thixotropy enhle yesistimu ihambisana nokusetshenziswa okusebenzayo.

2.2.2 Umphumela wokuminyana kwenkokhiso:ifomu le-logarithmic lefomula ye-Spencer-Dillon empirical ikhethiwe, lapho i-viscosity ye-zero-cut, b ihlala njalo ekugxilweni okufanayo kanye nezinga lokushisa elihlukile, futhi iyanda ngokunyuka kokugxila ezingeni lokushisa elifanayo. Ngokwezibalo zomthetho wamandla owamukelwa u-Onogi ngo-1966, u-M uyisisindo samangqamuzana e-polymer, u-A no-B ama-constants, futhi u-c yingxenyana enkulu (%). Fig.5 Amajika amathathu anamaphuzu okuguquguquka asobala azungeze u-0.6%, okungukuthi, kukhona ingxenyenamba yesisindo esibucayi. Ngaphezulu kuka-0.6%, i-viscosity ye-zero-shear ikhula ngokushesha ngokwanda kokugxila C. Amajika amasampula amathathu ane-charge density ehlukene asondelene kakhulu. Ngokuphambene, uma ingxenyenamba yenqwaba iphakathi kuka-0.2% no-0.8%, i-viscosity ye-zero-cut yesampula ye-LR enomthamo omncane weshajile inkulu kakhulu, ngoba inhlangano yebhondi ye-hydrogen idinga othintana naye othile. Ngakho-ke, ukuminyana kokushaja kuhlobene eduze nokuthi ama-macromolecules angahlelwa ngendlela ehlelekile futhi ehlangene; ngokuhlolwa kwe-DSC, kutholakala ukuthi i-LR inenani eliphakeme elicwebezelayo elibuthakathaka, elibonisa ukuminyana kweshaja okufanele, futhi i-viscosity ye-zero-shear iphezulu ekugxiliseni okufanayo. Uma ingxenye enkulu ingaphansi kuka-0.2%, i-LR incane kakhulu, ngoba kusixazululo se-dilute, ama-macromolecules ane-low density ye-charge kungenzeka ukuthi enze i-coil orientation, ngakho-ke i-viscosity ye-zero-shear iphansi. Lokhu kunokubaluleka kokuqondisa okuhle mayelana nokusebenza kokuqina.

2.2.3 pH umphumela: Umdwebo 6 umphumela okalwa nge-pH ehlukene phakathi kwebanga lika-0.05% kuya ku-2.5% wengxenyana yesisindo. Kukhona iphoyinti lokuguquguquka elizungeze u-0.45%, kodwa amajika amathathu acishe adlulelane, okubonisa ukuthi i-pH ayinawo umthelela osobala ku-zero-shear viscosity, ehluke kakhulu ekuzweleni kwe-anionic cellulose ether kuya ku-pH.

3. Isiphetho

Isixazululo se-aqueous se-KG-30M sicwaningwa yi-LLS, futhi ukusatshalaliswa kwerediyasi ye-hydrodynamic okutholiwe kuyinani eliphakeme elilodwa. Kusukela ku-engeli yokuncika kanye nesilinganiso se-Rg/Rb, kungase kuthiwe umumo wayo usondelene nendingilizi, kodwa awuvamile ngokwanele. Ukuze uthole izixazululo ze-CCE ezinobunzima obuthathu bokushaja, i-viscosity iyanda ngokukhula kokugxila, kodwa inombolo yokuzingela ye-Newton n iyancipha kuqala, bese iguquguquka futhi iphakame; I-pH inomthelela omncane ku-viscosity, futhi ukuminyana kweshaja okumaphakathi kungathola i-viscosity ephezulu .