Imithelela Yezinto Ezihlukile kanye Nesisindo Sengqamuzana Ezimpahleni Ezingaphezulu Ze-Nonionic Cellulose Ether

Ngokusho kwethiyori ka-Washburn yokukhulelwa (i-Penetration Theory) kanye nethiyori ehlanganisiwe ka-van Oss-Good-Chaudhury (Ithiyori Ehlanganisa) kanye nokusetshenziswa kobuchwepheshe be-columnar wick (I-Column Wicking Technique), ama-ether amaningana angewona ionic cellulose, njenge-methyl cellulose i-cellulose, i-hydroxypropyl cellulose ne-hydroxypropyl methylcellulose kwahlolwa. Ngenxa yezindawo ezihlukile ezihlukile, amadigri okushintsha kanye nezisindo zamangqamuzana alawa ma-cellulose ether, amandla awo angaphezulu nezingxenye zawo kuhluke kakhulu. Idatha ibonisa ukuthi isisekelo se-Lewis se-non-ionic cellulose ether sikhulu kune-Lewis acid, futhi ingxenye eyinhloko yamandla amahhala angaphezulu amandla e-Lifshitz-van der Waals. Amandla angaphezulu e-hydroxypropyl nokwakheka kwawo kukhulu kunalawo e-hydroxymethyl. Ngaphansi kwesisekelo sendawo efanayo kanye nezinga lokushintsha, amandla angaphezulu amahhala e-hydroxypropyl cellulose alingana nesisindo samangqamuzana; kuyilapho amandla angaphezulu amahhala e-hydroxypropyl methylcellulose elingana nezinga lokushintsha futhi ephikisana ngokuphambene nesisindo samangqamuzana. Ucwaningo luphinde lwathola ukuthi amandla angaphezulu e-hydroxypropyl ne-hydroxypropylmethyl ku-non-ionic cellulose ether abonakala emakhulu kunamandla angaphezulu e-cellulose, futhi ukuhlola kufakazela ukuthi amandla angaphezulu e-cellulose ehloliwe kanye nokwakheka kwayo ehambisana nezincwadi.

Amagama angukhiye: i-nonionic cellulose ethers; ama-substitute namadigri okushintsha; isisindo samangqamuzana; izakhiwo ezingaphezulu; ubuchwepheshe be-wick

I-Cellulose ether iyisigaba esikhulu sokuphuma kwe-cellulose, esingahlukaniswa sibe ama-ether anionic, cationic kanye nama-nonionic ngokuya ngesakhiwo samakhemikhali sabasekeli bawo be-ether. I-Cellulose ether futhi ingomunye wemikhiqizo yokuqala eyacwaningwa futhi yakhiqizwa kumakhemikhali e-polymer. Kuze kube manje, i-cellulose ether isetshenziswe kabanzi kwezokwelapha, inhlanzeko, izimonyo kanye nemboni yokudla.

Nakuba ama-cellulose ethers, afana ne-hydroxymethylcellulose, i-hydroxypropylcellulose kanye ne-hydroxypropylmethylcellulose, akhiqizwa ezimbonini futhi eziningi zezindawo zabo zihlolisisiwe, amandla abo angaphezulu, izakhiwo ze-Alkali-reactive azikabikwa kuze kube manje. Njengoba iningi lale mikhiqizo lisetshenziswa endaweni ewuketshezi, futhi izici ezingaphezulu, ikakhulukazi izici zokusabela kwe-acid-base, zingase zibe nomthelela ekusetshenzisweni kwayo, kubaluleke kakhulu ukufunda nokuqonda izici zamakhemikhali ezingaphezulu zale ether ye-cellulose yokuhweba.

Uma kucatshangelwa ukuthi amasampula e-cellulose derivatives alula kakhulu ukushintsha ngokushintsha kwezimo zokulungiselela, leli phepha lisebenzisa imikhiqizo yokuhweba njengamasampula ukuze kubonakale amandla abo angaphezulu, futhi ngokusekelwe kulokhu, ithonya lama-substituents kanye nezisindo zamangqamuzana zemikhiqizo enjalo ebusweni. izakhiwo ziyafundwa.

1. Ingxenye yokuhlola

1.1 Izinto ezisetshenziswayo

I-non-ionic cellulose ether esetshenziswe ekuhloleni iwumkhiqizo weI-KIMA CHEMICAL CO., LTD,. Amasampula awazange enzelwe noma yikuphi ukwelashwa ngaphambi kokuhlolwa.

Uma kucatshangelwa ukuthi okuphuma ku-cellulose kwenziwa nge-cellulose, lezi zakhiwo ezimbili ziseduze, futhi izakhiwo ezingaphezulu ze-cellulose zibikwe ezincwadini, ngakho leli phepha lisebenzisa i-cellulose njengesampula evamile. Isampula ye-cellulose esetshenzisiwe yabizwa ngekhodi-C8002 futhi yathengwa kuyoKIMA, CN. Isampula ayizange iphathwe noma yikuphi ukwelashwa ngesikhathi sokuhlolwa.

Ama-reagents asetshenziswe ekuhloleni yilawa: i-ethane, i-dioodomethane, amanzi e-deionized, i-formamide, i-toluene, i-chloroform. Zonke izinto eziwuketshezi zaziyimikhiqizo ehlanzekile ngaphandle kwamanzi ayethengiswa.

1.2 Indlela yokuhlola

Kulesi sivivinyo, inqubo yokufaka ikholomu yamukelwa, futhi ingxenye (cishe i-10 cm) ye-pipette evamile enobubanzi obungaphakathi obungu-3 mm yasikwa njengethubhu yekholomu. Faka u-200 mg wesampula eyimpuphu eshubhuni yekholomu isikhathi ngasinye, bese uyinyakazisa ukuze ilingane futhi uyibeke iqonde phansi esitsheni sengilazi enobubanzi obungango-3 cm, ukuze uketshezi lukwazi ukukhangiswa ngokuzenzakalelayo. Kala u-1 mL woketshezi oluzohlolwa bese ulufaka esitsheni sengilazi, bese urekhoda isikhathi sokucwiliswa t nebanga lokucwiliswa elingu-X ngesikhathi esifanayo. Zonke izivivinyo zenziwa ekamelweni lokushisa (25±1°C). Idatha ngayinye iyisilinganiso sezilingo ezintathu eziyimpinda.

1.3 Ukubalwa kwedatha yokuhlola

Isisekelo setiyetha sokusetshenziswa kwendlela yokufaka ikholomu ukuhlola amandla angaphezulu ezinto eziyimpushana i-Washburn impregnation equation (i-Washburn penetration equation).

1.3.1 Ukunqunywa kwe-capillary radius esebenzayo Reff yesampula elinganisiwe

Uma usebenzisa ifomula yokucwiliswa kwe-Washburn, umbandela wokuzuza ukumanzisa okuphelele ngu-cos=1. Lokhu kusho ukuthi uma uketshezi lukhethwa ukuze lucwiliswe kokuqinile ukuze sifinyelele isimo esimanzi ngokugcwele, singabala i-capillary radius Reff yesampula elinganisiwe ngokuhlola ibanga lokucwiliswa kanye nesikhathi ngokwesimo esikhethekile sefomula yokucwiliswa kwe-Washburn.

1.3.2 I-Lifshitz-van der Waals iphoqelela ukubala kwesampula elinganisiwe

Ngokusho kwemithetho ehlanganisayo ka-van Oss-Chaudhury-Good, ubudlelwano phakathi kokusabela phakathi koketshezi nokuqinile.

1.3.3 Ukubalwa kwe-Lewis acid-base force yamasampuli akaliwe

Ngokuvamile, izakhiwo ze-acid-base yezinto eziqinile zilinganiselwa kudatha efakwe emanzini ne-formamide. Kodwa kulesi sihloko, sithole ukuthi ayikho inkinga lapho kusetshenziswa le pair of polar liquids ukukala i-cellulose, kodwa ekuhlolweni kwe-cellulose ether, ngoba ukuphakama kokucwiliswa kwesistimu yesisombululo se-polar yamanzi / i-formamide ku-cellulose ether iphansi kakhulu. , okwenza kube nzima kakhulu ukuqopha isikhathi. Ngakho-ke, uhlelo lwesisombululo se-toluene/chloroform olwethulwa yiChibowsk lukhethiwe. NgokukaChibowski, uhlelo lwe-toluene/chloroform polar solution nalo luyinketho. Lokhu kungenxa yokuthi lezi ziphuzo ezimbili zine-acidity ekhetheke kakhulu kanye ne-alkalinity, isibonelo, i-toluene ayinayo i-Lewis acid, futhi i-chloroform ayinayo i-Lewis alkalinity. Ukuze uthole idatha etholwe isistimu yesisombululo se-toluene/chloroform eduze nesistimu yesisombululo esinconyiwe samanzi/i-formamide, sisebenzisa lezi zinhlelo ezimbili eziwuketshezi ezishisayo ukuze sihlole i-cellulose ngesikhathi esisodwa, bese sithola ukunwetshwa okuhambisanayo noma ukufinyezwa kwamakhoyethi. ngaphambi kokufaka idatha etholwe ngokumithisa i-cellulose ether nge-toluene/chloroform iseduze neziphetho ezitholiwe zohlelo lwamanzi/i-formamide. Njengoba ama-cellulose ether etholakala ku-cellulose futhi kukhona ukwakheka okufanayo phakathi kwakho kokubili, le ndlela yokulinganisa ingase isebenze.

1.3.4 Ukubalwa kwamandla amahhala angaphezulu

2. Imiphumela Nezingxoxo

2.1 I-Cellulose ejwayelekile

Njengoba imiphumela yethu yokuhlolwa kumasampula ajwayelekile we-cellulose ithole ukuthi le datha ivumelana kahle naleyo ebikwe ezincwadini, kunengqondo ukukholelwa ukuthi imiphumela yokuhlolwa kuma-cellulose ether kufanele futhi icatshangelwe.

2.2 Imiphumela yokuhlolwa nengxoxo ye-cellulose ether

Ngesikhathi sokuhlolwa kwe-cellulose ether, kunzima kakhulu ukurekhoda ibanga lokucwiliswa kanye nesikhathi ngenxa yokuphakama okuphansi kakhulu kokucwiliswa kwamanzi kanye ne-formamide. Ngakho-ke, leli phepha likhetha uhlelo lwesisombululo se-toluene/chloroform njengenye isixazululo, futhi lilinganisela i-Lewis acidity ye-cellulose ether ngokusekelwe emiphumeleni yokuhlola yamanzi/i-formamide ne-toluene/chloroform ku-cellulose kanye nobudlelwano obulinganayo phakathi kwezinhlelo ezimbili zesixazululo. namandla ane-alkaline.

Ukuthatha i-cellulose njengesampula evamile, uchungechunge lwezimpawu ze-acid-base zama-cellulose ethers ziyanikezwa. Njengoba umphumela wokumithisa i-cellulose ether nge-toluene/chloroform ihlolwe ngokuqondile, iyakholisa.

Lokhu kusho ukuthi uhlobo nesisindo samangqamuzana sezinto ezihlukile zithinta izakhiwo ze-acid-base ze-cellulose ether, kanye nobudlelwane phakathi kwezinto ezimbili ezithatha indawo, i-hydroxypropyl ne-hydroxypropylmethyl, ezakhiweni ze-acid-base ze-cellulose ether kanye nesisindo se-molecular ngokuphambene ngokuphelele. Kodwa futhi kungahlotshaniswa nokuthi amalungu ePhalamende angamalungu axubile.

Njengoba okufakwe esikhundleni se-MO43 ne-K8913 kuhlukile futhi kunesisindo samangqamuzana esifanayo, isibonelo, indawo yangaphambili i-hydroxymethyl futhi ebambele yakamuva i-hydroxypropyl, kodwa isisindo samangqamuzana kokubili siyi-100,000, ngakho-ke kusho ukuthi Isisekelo sesisindo samangqamuzana esifanayo Ngaphansi kwezimo, i-S+ ne-S- yeqembu le-hydroxymethyl ingase ibe yincane kuneqembu le-hydroxypropyl. Kodwa izinga lokufaka esikhundleni lingenzeka, ngoba izinga lokushintshwa kwe-K8913 licishe libe ngu-3.00, kuyilapho lelo le-MO43 liyi-1.90 kuphela.

Njengoba izinga lokufaka esikhundleni kanye ne-substitutes ye-K8913 ne-K9113 lifana kodwa isisindo samangqamuzana kuphela esihlukile, ukuqhathanisa phakathi kokubili kubonisa ukuthi i-S + ye-hydroxypropyl cellulose iyancipha ngokunyuka kwesisindo samangqamuzana, kodwa i-S- iyanda ngokuphambene nalokho. .

Kusukela esifinyezweni semiphumela yokuhlola yamandla angaphezulu kwawo wonke ama-ether e-cellulose kanye nezingxenye zawo, kungabonakala ukuthi noma ngabe i-cellulose noma i-cellulose ether, ingxenye eyinhloko yamandla abo angaphezulu amandla e-Lifshitz-van der Waals, ebalwa cishe 98%~99%. Ngaphezu kwalokho, amandla e-Lifshitz-van der Waals alawa ma-nonionic cellulose ethers (ngaphandle kwe-MO43) nawo makhulu kakhulu kunalawo e-cellulose, okubonisa ukuthi inqubo ye-etherification ye-cellulose iyinqubo yokwandisa amandla e-Lifshitz-van der Waals. Futhi lokhu kwanda kuholela ekubeni amandla angaphezulu e-cellulose ether abe makhulu kunalawo e-cellulose. Lesi simo siyathakazelisa kakhulu ngoba lawa ma-cellulose ethers avame ukusetshenziswa ekukhiqizeni ama-surfactants. Kodwa idatha iyaphawuleka, hhayi kuphela ngenxa yokuthi idatha mayelana nesampula evamile yesithenjwa ehlolwe kulokhu kuhlolwa ihambisana kakhulu nenani elibikwe ezincwadini, idatha emayelana nesampula evamile yesithenjwa ihambisana kakhulu nenani elibikwe ezincwadini, ngoba isibonelo: wonke lawa ma-cellulose I-SAB yama-ether incane kakhulu kune-cellulose, futhi lokhu kungenxa yezisekelo zawo ezinkulu ze-Lewis. Ngaphansi kwesisekelo sendawo efanayo kanye nezinga lokushintsha, amandla angaphezulu amahhala e-hydroxypropyl cellulose alingana nesisindo samangqamuzana; kuyilapho amandla angaphezulu amahhala e-hydroxypropyl methylcellulose elingana nezinga lokushintsha futhi ephikisana ngokuphambene nesisindo samangqamuzana.

Ngaphezu kwalokho, ngenxa yokuthi ama-cellulose ether ane-SLW enkulu kune-cellulose, kodwa sesiyazi kakade ukuthi ukuhlakazeka kwawo kungcono kune-cellulose, ngakho-ke kungacatshangwa ngaphambilini ukuthi ingxenye eyinhloko ye-SLW eyakha ama-nonionic cellulose ethers kufanele kube amandla aseLondon.

3. Isiphetho

Ucwaningo luye lwabonisa ukuthi uhlobo lwe-substitute, degree of substitution kanye nesisindo samangqamuzana kunomthelela omkhulu kumandla angaphezulu kanye nokwakheka kwe-non-ionic cellulose ether. Futhi lo mphumela ubonakala unokujwayelekile okulandelayo:

(1) I-S+ ye-non-ionic cellulose ether incane kune-S-.

(2) Amandla angaphezulu we-nonionic cellulose ether aphethwe amandla ka-Lifshitz-van der Waals.

(3) Isisindo sengqamuzana nezinye ezibambele zinomthelela kumandla angaphezulu wama-non-ionic cellulose ether, kodwa kuncike kakhulu ohlotsheni lwama-substitutes.

(4) Ngaphansi kwesisekelo sento efanayo kanye nezinga lokushintsha, amandla angaphezulu amahhala e-hydroxypropyl cellulose alingana nesisindo se-molecule; kuyilapho amandla angaphezulu amahhala e-hydroxypropyl methylcellulose elingana nezinga lokushintsha futhi ephikisana ngokuphambene nesisindo samangqamuzana.

(5) Inqubo ye-etherification ye-cellulose iyinqubo lapho amandla e-Lifshitz-van der Waals enyuka, futhi kuyinqubo lapho i-acidity ye-Lewis incipha futhi i-Lewis alkalinity iyanda.