Iipropati zeCationic Cellulose Ether Solution

Iipropati zesisombululo se-dilute ye-high-charge-density cationic cellulose ether (KG-30M) kumaxabiso ahlukeneyo e-pH yaphononongwa ngesixhobo sokuchithachitha i-laser, ukusuka kwiradiyo ye-hydrodynamic (Rh) kwii-angles ezahlukeneyo, kwaye ingcambu ithetha i-square radius yokujikeleza. Rg Umlinganiselo ukuya kwi-Rh ubonisa ukuba imilo yayo ayiqhelekanga kodwa ikufutshane nengqukuva. Emva koko, ngoncedo lwe-rheometer, izisombululo ezintathu ezigxininisiweyo ze-cationic cellulose ethers ezinoxinano lwentlawulo eyahlukeneyo zafundwa ngokweenkcukacha, kwaye impembelelo yoxinaniso, ixabiso le-pH kunye nokuxinana kwentlawulo yayo kwiipropati zayo ze-rheological zaxoxwa. Njengoko ugxininiso lusanda, i-exponent ye-Newton yaqala yehla kwaye yehla. Ukuguquguquka okanye ukuphindaphinda kwenzeka, kwaye ukuziphatha kwe-thixotropic kwenzeka kwi-3% (iqhekeza elikhulu). Ukuxinana kwentlawulo ephakathi kunenzuzo ukufumana i-viscosity ephezulu ye-zero-shear, kwaye i-pH inempembelelo encinci kwi-viscosity yayo.

Amagama angundoqo:i-cationic cellulose ether; imofoloji zero shear viscosity; irheology

I-cellulose derivatives kunye neepolymers zabo ezisebenzayo eziguquliweyo ziye zasetyenziswa ngokubanzi kwiimveliso ze-physiological and sanitary, i-petrochemicals, amayeza, ukutya, iimveliso zokunyamekela, ukupakishwa, njl njl. amandla, isetyenziswa ngokubanzi kwiikhemikhali zemihla ngemihla, ngakumbi iishampu, kwaye inokuphucula ukuhambelana kweenwele emva kokuhlamba. Ngexesha elifanayo, ngenxa yokuhambelana kwayo kakuhle, inokusetyenziswa kwii-shampoos ezimbini-nye kunye nazo zonke. Ikwanalo nethemba lesicelo esihle kwaye itsale umdla kumazwe ahlukeneyo. Kuye kwaxelwa kuncwadi ukuba izisombululo ze-cellulose eziphuma kwi-cellulose zibonisa ukuziphatha okufana ne-Newtonian fluid, i-pseudoplastic fluid, i-thixotropic fluid kunye ne-viscoelastic fluid kunye nokwanda koxinaniso, kodwa i-morphology, i-rheology kunye nezinto ezichaphazelayo ze-cationic cellulose ether kwisisombululo samanzi. iingxelo zophando. Eli phepha ligxile ekuziphatheni kwe-rheological ye-quaternary ammonium modified cellulose isisombululo se-aqueous, ukwenzela ukubonelela ngesalathiso sokusetyenziswa okusebenzayo.

1. Inxalenye yovavanyo

1.1 Iimathiriyeli ekrwada

I-Cationic cellulose ether (KG-30M, JR-30M, LR-30M); Imveliso yaseCanada iDow Chemical Company, ebonelelwa yiProcter & Gamble Company Kobe R&D Centre eJapan, ilinganiswe nguVario EL elemental analyzer (German Elemental Company), isampuli Umxholo wenitrogen ngu-2.7%, 1.8%, 1.0% ngokulandelanayo (ubuninzi bentlawulo I-1.9 Meq/g, 1.25 Meq/g, 0.7 Meq/g ngokulandelelanayo), kwaye ivavanywa yi-German ALV-5000E laser light Scattering instrument (LLS) ilinganisa ubunzima bayo obuqhelekileyo bemolekyuli malunga ne-1.64×106g/mol.

1.2 Ukulungiswa kwesisombululo

Isampulu yahlanjululwa ngokucoca, i-dialysis kunye ne-freeze-drying. Viyisha uthotho lweesampulu zobungakanani ezintathu ngokulandelelanayo, kwaye wongeze isisombululo esisezantsi se-buffer kunye ne-pH 4.00, 6.86, 9.18 ukulungiselela ugxininiso olufunekayo. Ukuze kuqinisekiswe ukuba iisampuli zachithwa ngokupheleleyo, zonke izisombululo zesampulu zibekwe kwi-stirrer magnetic kwiiyure ze-48 ngaphambi kokuvavanya.

1.3 Umlinganiselo wokusabalalisa ukukhanya

Sebenzisa i-LLS ukulinganisa ubunzima-umndilili wemolekyuli yesampulu kwisisombululo esinamanzi, iradiyasi ye-hydrodynamic kunye neengcambu ezithetha iradiyasi yesikwere sokujikeleza xa i-coefficient yeVilli yesibini kunye nee-engile ezahlukeneyo, kwaye uqonde ukuba le cationic cellulose ether ingaphakathi. isisombululo esinamanzi ngokwemeko yomlinganiselo.

1.4 Umlinganiselo we-Viscosity kunye nophando lwe-rheological

Isisombululo esigxininisiweyo se-CCE safundwa yi-rheometer ye-Brookfield RVDV-III+, kunye nefuthe lokuxinana, ukuxinwa kwentlawulo kunye nexabiso le-pH kwiipropati ze-rheological ezifana ne-viscosity yesampuli yaphandwa. Kwiindawo eziphezulu, kuyimfuneko ukuphanda i-thixotropy yayo.

2. Iziphumo kunye nengxoxo

2.1 Uphando malunga nokuSasaza koKhanya

Ngenxa yesakhiwo sayo esikhethekileyo seemolekyuli, kunzima ukuba khona kwimo yemolekyuli enye nakwi-solvent elungileyo, kodwa ngendlela yeemicelles ezithile ezizinzileyo, amaqoqo okanye imibutho.

Xa isisombululo se-aqueous dilute (~o.1%) se-CCE sabonwa nge-microscope epholileyo, phantsi kwemvelaphi yebala elimnyama elinqamlezayo, iindawo eziqaqambileyo kunye nemivalo eqaqambileyo yavela. Iphinda ibonakaliswe ngokusasazwa kokukhanya, iradiyasi eguquguqukayo ye-hydrodynamic kwi-pH eyahlukeneyo kunye nee-engile, ingcambu ye-square radius yokujikeleza kunye ne-coefficient ye-Villi yesibini efunyenwe kwi-Berry diagram idweliswe kwi-Tab. 1. Igrafu yokusabalalisa i-hydrodynamic radius function efunyenwe kwi-concentration ye-10-5 ubukhulu becala iphakamileyo eyodwa, kodwa ukusabalalisa kubanzi kakhulu (umzobo 1), okubonisa ukuba kukho imibutho ye-molecular-level kunye ne-aggregates enkulu kwinkqubo. ; Kukho utshintsho, kwaye ixabiso le-Rg / Rb lijikeleze i-0.775, ebonisa ukuba imilo ye-CCE kwisisombululo isondele kwi-spherical, kodwa ayiqhelekanga ngokwaneleyo. Impembelelo ye-pH kwi-Rb kunye ne-Rg ayibonakali. I-counterion kwisisombululo se-buffer isebenzisana ne-CCE ukukhusela intlawulo kwikhonkco layo elisecaleni kwaye iyenze iyancipha, kodwa umahluko uyahluka ngohlobo lwe-counterion. Umlinganiselo wokusasazwa kokukhanya kweepolymers ezihlawulweyo zichaphazeleka kwintsebenziswano yamandla omde kunye nokuphazamiseka kwangaphandle, ngoko ke kukho iimpazamo ezithile kunye nemida kwiimpawu zeLLS. Xa ubukhulu beqhekeza bungaphezulu kwe-0.02%, kukho iincopho eziphindwe kabini ezingenakuhlukaniswa okanye iincopho ezininzi kumzobo wokusabalalisa i-Rh. Njengoko i-concentration inyuka, i-Rh nayo iyanda, ebonisa ukuba ii-macromolecules ezininzi zidibene okanye zidibene. Xa uCao et al. kusetyenziswe ukukhanya okukhanyayo ukufunda i-copolymer ye-carboxymethyl cellulose kunye ne-face-active macromers, bekukho iincopho eziphindwe kabini ezingenakuhlukaniswa, enye yazo yayiphakathi kwe-30nm kunye ne-100nm, emele ukwakheka kweemicelles kwinqanaba le-molecular, kwaye enye Incopho yeRh enkulu, ethathwa ngokuba yi-aggregate, efana neziphumo ezichazwe kweli phepha.

2.2 Uphando ngokuziphatha kwerheological

2.2.1 Isiphumo sokugxila:Ukulinganisa i-viscosity ebonakalayo yezisombululo ze-KG-30M kunye nogxininiso oluhlukeneyo kumazinga ahlukeneyo okucheba, kwaye ngokwendlela ye-logarithmic ye-equation yomthetho wamandla ecetywayo ngu-Ostwald-Dewaele, xa iqhezu lobunzima lingadluli i-0.7%, kunye noluhlu lwemigca ethe tye. kunye ne-linear coefficients yokulungelelanisa ngaphezulu kwe-0.99 yafunyanwa. Kwaye njengoko ugxininiso lukhula, ixabiso le-Newton's exponent n liyancipha (konke ngaphantsi kwe-1), kubonisa i-pseudoplastic fluid ebonakalayo. Iqhutywa ngamandla e-shear, i-macromolecular chains iqala ukugoba kwaye ijikeleze, ngoko ke i-viscosity iyancipha. Xa i-mass fraction ingaphezu kwe-0.7%, i-coefficient yokulungelelaniswa komgca wendlela echanekileyo efunyenweyo iyancipha (malunga ne-0.98), kwaye i-n iqala ukuguquguquka okanye ukunyuka kunye nokunyuka koxinzelelo; xa i-mass fraction ifikelela kwi-3% (umzobo 2), itheyibhile I-viscosity ebonakalayo iqala ukwanda kwaye iyancipha ngokunyuka kwezinga le-shear. Olu chungechunge lweziganeko luhluke kwiingxelo zezinye izixazululo ze-anionic kunye ne-cationic polymer. Ixabiso lika-n liyenyuka, oko kukuthi, ipropathi engeyoyaseNewtonian ibuthathaka; I-Newtonian fluid i-viscous liquid, kwaye i-intermolecular slippage iyenzeka phantsi kwesenzo soxinzelelo lwe-shear, kwaye ayikwazi ukufunyanwa; Ulwelo olungelulo olwaseNewtonian luqulethe indawo enwebekayo enokufunyanwa kunye nenxalenye ye-viscous engafumanekiyo. Ngaphantsi kwesenzo soxinzelelo lwe-shear, i-slip engenakuguqulwa phakathi kweeamolekyu iyenzeka, kwaye ngelo xesha, ngenxa yokuba i-macromolecules yoluliwe kwaye ijoliswe kwi-shear, inxalenye ye-elastic efumanekayo yenziwa. Xa amandla angaphandle esusiwe, i-macromolecules idla ngokubuyela kwifom egobileyo yokuqala, ngoko ke ixabiso le-n liyenyuka. Ugxininiso luqhubeka lukhula ukwenza isakhiwo sothungelwano. Xa uxinzelelo lwe-shear luncinci, aluyi kutshatyalaliswa, kwaye kuya kwenzeka kuphela i-elastic deformation. Ngeli xesha, i-elasticity iya kunyuswa ngokuthe ngqo, i-viscosity iya kuba buthathaka, kwaye ixabiso le-n liya kuncipha; ngelixa uxinzelelo lokucheba lukhula ngokuthe ngcembe ngexesha lenkqubo yokulinganisa, ngoko ke n Ixabiso liyaguquguquka. Xa i-mass fraction ifikelela kwi-3%, i-viscosity ebonakalayo iqala ukwanda kwaye iyancipha, kuba i-shear encinci ikhuthaza ukungqubana kwama-macromolecules ukwenza ii-aggregates ezinkulu, ngoko i-viscosity iphakama, kwaye uxinzelelo lwe-shear luyaqhubeka nokuphula i-aggregates. , i-viscosity iya kuncipha kwakhona.

Kuphando lwe-thixotropy, seta isantya (r/min) ukufikelela kwi-y oyifunayo, yandisa isantya ngamaxesha aqhelekileyo de ifikelele kwixabiso elibekiweyo, emva koko wehle ngokukhawuleza ukusuka kwisantya esiphezulu ubuyela kwixabiso lokuqala ukuze ufumane oluhambelanayo. Uxinzelelo lwe-shear, ubudlelwane balo kunye nesantya se-shear kuboniswe kwi-Fig. 3. Xa i-mass fraction ingaphantsi kwe-2.5%, i-curve ephezulu kunye ne-curve ephantsi idibanisa ngokupheleleyo, kodwa xa i-mass fraction i-3%, imigca emibini ayikho. Umgca ojonge ezantsi usalele ngasemva, nto leyo ebonisa ukuba thixotropy.

Ukuxhomekeka kwexesha loxinzelelo lwe-chear kwaziwa ngokuba yi-rheological resistance. Ukumelana neRheological kukuziphatha okubonakalayo kolwelo lwe-viscoelastic kunye nolwelo olunezakhiwo ze-thixotropic. Kufunyaniswa ukuba i-y enkulu ikwiqhekeza elifanayo lobunzima, i-r ngokukhawuleza ifikelela kwi-equilibrium, kwaye ixesha lokuxhomekeka lincinci; kwiqhekeza eliphantsi lobunzima (<2%), i-CCE ayibonisi ukuxhathisa kwe-rheological. Xa i-mass fraction inyuka ukuya kwi-2.5%, ibonisa ukuxhomekeka kwexesha eliqinileyo (umzobo 4), kwaye kuthatha malunga nemizuzu eyi-10 ukufikelela kwi-equilibrium, ngelixa i-3.0%, ixesha lokulinganisa lithatha imizuzu engama-50. I-thixotropy enhle yenkqubo ifanelekile kwisicelo esisebenzayo.

2.2.2 Isiphumo sokuxinana kwentlawulo:ifom ye-logarithmic ye-Spencer-Dillon ye-empirical formula ikhethiwe, apho i-viscosity ye-zero-cut, i-b ihlala igxininisekile kunye nobushushu obuhlukeneyo, kwaye inyuka ngokunyuka koxinzelelo kwiqondo lokushisa elifanayo. Ngokomthetho we-equation wamandla owamkelwa ngu-Onogi ngo-1966, i-M yi-molecular mass ye-polymer, i-A kunye ne-B ziyi-constants, kwaye i-c yi-mass fraction (%). ikhiwane.5 Iigophe ezintathu zineengongoma ezicacileyo zokuguquguquka malunga ne-0.6%, oko kukuthi, kukho iqhezu lobunzima elibalulekileyo. Ngaphezulu kwe-0.6%, i-viscosity ye-zero-shear ikhula ngokukhawuleza ngokunyuka kwe-concentration C. Iingqungquthela zeesampulu ezintathu ezinobunzima obuhlukeneyo bentlawulo zisondele kakhulu. Ngokwahlukileyo, xa iqhezu lobunzima liphakathi kwe-0.2% kunye ne-0.8%, i-viscosity ye-zero-cut ye-sampulu ye-LR kunye neyona nto incinci yokuxinwa kwentlawulo yeyona inkulu, kuba umbutho we-hydrogen bond ufuna umfowunelwa othile. Ngoko ke, ukuxinana kwentlawulo kuhambelana ngokusondeleyo nokuba ingaba i-macromolecules ingacwangciswa ngendlela ecwangcisiweyo kunye ne-compact; ngovavanyo lwe-DSC, kufumaniseke ukuba i-LR inencopho yecrystallization ebuthathaka, ebonisa ingxinano yentlawulo efanelekileyo, kwaye i-viscosity ye-zero-shear iphezulu kwinqanaba elifanayo. Xa i-mass fraction ingaphantsi kwe-0.2%, i-LR iyona nto incinci, kuba kwisisombululo se-dilute, i-macromolecules ene-low charge density inokwenzeka ukuba yenze i-coil orientation, ngoko i-viscosity ye-zero-shear iphantsi. Oku kunokubaluleka kwesikhokelo esilungileyo malunga nokusebenza kokuqina.

2.2.3 pH isiphumo: Umzobo 6 sisiphumo esilinganiswe kwi-pH eyahlukileyo phakathi koluhlu lwe-0.05% ukuya kwi-2.5% yeqhezu lobunzima. Kukho indawo yokuguquguquka ejikeleze i-0.45%, kodwa iigophe ezithathu ziphantse zadibana, nto leyo ebonisa ukuba i-pH ayinasiphumo esicacileyo kwi-zero-shear viscosity, eyahluke kakhulu kubuntununtunu be-anionic cellulose ether ukuya kwi-pH.

3. Isiphelo

I-KG-30M i-dilute i-aqueous solution ifundwa yi-LLS, kwaye i-hydrodynamic radius distribution efunyenweyo yinto enye. Ukusuka kwi-engile yokuxhomekeka kunye ne-Rg / Rb ratio, kunokuchazwa ukuba imilo yayo isondele kwi-spherical, kodwa ayiqhelekanga ngokwaneleyo. Kwizisombululo zeCCE ezinoxinzelelo lwentlawulo emithathu, i-viscosity iyanda ngokunyuka koxinzelelo, kodwa inombolo yokuzingela yeNewton n iyancipha kuqala, emva koko iguquguquke kwaye iphakame; I-pH inempembelelo encinci kwi-viscosity, kwaye ukuxinwa kwentlawulo ephakathi kunokufumana i-viscosity ephezulu.