I-sodium carboxymethyl cellulose, ebizwa ngokuthi i-carboxymethyl cellulose (CMC) iwuhlobo lwe-fiber ether ephezulu ye-polymer elungiswe ukuguqulwa kwamakhemikhali kwe-cellulose yemvelo.Ukwakheka kwayo ngokuyinhloko iyunithi ye-D-glucose ngo-β (1→4) Okhiye baxhunywe ndawonye.
I-CMC iyimpushana emhlophe noma eyi-milky emhlophe noma ama-granules, anobuningi obungu-0.5-0.7 g/cm3, cishe ayinaphunga, ayinambitheki, futhi i-hygroscopic.Ihlakazeka kalula emanzini ukuze yenze isixazululo se-colloidal esobala, esingancibiliki kumakhemikhali ezinto eziphilayo njenge-ethanol.I-pH ye-aqueous solution engu-1% ingu-6.5-8.5, lapho i-pH>10 noma <5, i-viscosity ye-mucilage iyancipha kakhulu, futhi ukusebenza kuba kuhle kakhulu uma i-pH=7.Izinzile ekushiseni, i-viscosity ikhuphuka ngokushesha ngaphansi kuka-20°C, futhi ishintsha kancane ku-45°C.Ukushisa isikhathi eside ngaphezu kuka-80°C kungashintsha i-colloid futhi kunciphise ngokuphawulekayo i-viscosity nokusebenza.Incibilika kalula emanzini futhi isisombululo sisobala;izinzile kakhulu kusisombululo se-alkaline, kodwa i-hydrolyzed kalula uma ihlangana ne-asidi, futhi izokwehla lapho inani le-pH liyi-2-3, futhi izophinde isabele ngosawoti wensimbi we-multivalent.
Ifomula yesakhiwo: C6H7(OH)2OCH2COONA Ifomula yemolekyuli: C8H11O5Na
Ukusabela okuyinhloko ukuthi: i-cellulose yemvelo kuqala ithola ukusabela kwe-alkalinization nge-NaOH, futhi ngokungezwa kwe-chloroacetic acid, i-hydrogen eqenjini le-hydroxyl kuyunithi ye-glucose ibhekana nokusabela esikhundleni seqembu le-carboxymethyl ku-chloroacetic acid.Kungabonakala kufomula yesakhiwo ukuthi kunamaqembu amathathu e-hydroxyl kuyunithi ngayinye ye-glucose, okungukuthi, amaqembu e-C2, C3, kanye ne-C6 hydroxyl.I-hydrogen eqenjini ngalinye le-hydroxyl ithathelwa indawo yi-carboxymethyl, echazwa njenge-degree of substitution of 3. Izinga lokushintshwa kwe-CMC lithinta ngokuqondile ukuncibilika, ukuxubha, ukuqina, ukuzinza, ukumelana ne-asidi kanye nokumelana nosawotiI-CMC .
Ngokuvamile kunenkolelo yokuthi uma izinga lokushintsha liseduze kuka-0.6-0.7, ukusebenza kwe-emulsifying kuba ngcono, futhi ngokwanda kwezinga lokushintshwa, ezinye izakhiwo ziyathuthukiswa ngokufanele.Lapho izinga lokushintsha lingaphezu kuka-0.8, ukumelana kwayo ne-asidi nokumelana nosawoti kuyathuthukiswa kakhulu..
Ukwengeza, kuphinde kushiwo ngenhla ukuthi kunamaqembu amathathu e-hydroxyl kuyunithi ngayinye, okungukuthi, amaqembu e-hydroxyl yesibili ye-C2 ne-C3 kanye neqembu le-hydroxyl eliyinhloko le-C6.Ngokombono, umsebenzi weqembu eliyinhloko le-hydroxyl mkhulu kunoweqembu lesibili le-hydroxyl, kodwa ngokusho komphumela we-isotopic we-C, iqembu le--OH ku-C2 I-acidic eyengeziwe, ikakhulukazi endaweni ye-alkali enamandla, umsebenzi wayo. inamandla kune-C3 ne-C6, ngakho-ke ijwayele ukusabela esikhundleni, ilandelwe yi-C6, futhi i-C3 ibuthakathaka kakhulu.
Eqinisweni, ukusebenza kwe-CMC akuhlobene kuphela nezinga lokushintsha, kodwa futhi nokufana kokusatshalaliswa kwamaqembu e-carboxymethyl kuyo yonke i-molecule ye-cellulose kanye nokushintshwa kwamaqembu e-hydroxymethyl kuyunithi ngayinye nge-C2, C3, ne-C6 i-molecule ngayinye.okuhlobene nokufana.Njengoba i-CMC iyinhlanganisela yomugqa eyenziwe nge-polymerized kakhulu, futhi iqembu layo le-carboxymethyl linokushintshwa okulinganayo ku-molecule, ama-molecule anomumo ohlukile lapho ikhambi lishiywe limile, nobude be-molecule yomugqa buhlukile uma kukhona amandla okugunda esixazululweni. .I-axis inomkhuba wokuphendukela ekuqondeni kokugeleza, futhi lokhu kuthambekela kuba namandla ngokunyuka kwezinga lokugunda kuze kube yilapho ukuqondiswa kokugcina kuhlelwe ngokuphelele.Lesi sici se-CMC sibizwa nge-pseudoplasticity.I-pseudoplasticity ye-CMC ihambisana ne-homogenization kanye nokuthuthwa kwamapayipi, futhi ngeke inambithe i-greasy obisini oluwuketshezi, okusiza ekukhishweni kwephunga lobisi..
Ukuze sisebenzise imikhiqizo ye-CMC, sidinga ukuqonda kahle imingcele eyinhloko njengokuzinza, i-viscosity, ukumelana ne-asidi, kanye ne-viscosity.Yazi ukuthi sikhetha kanjani umkhiqizo olungile.
Imikhiqizo ye-CMC ene-viscosity ephansi inokunambitheka okuqabulayo, i-viscosity ephansi, futhi cishe ayinawo umuzwa owugqinsi.Zisetshenziswa kakhulu kumasoso akhethekile neziphuzo.Uketshezi oluphuzwayo lwezempilo nakho kuyisinqumo esihle.
Imikhiqizo ye-Medium-viscosity ye-CMC isetshenziswa kakhulu eziphuzweni eziqinile, eziphuzweni ezijwayelekile zamaprotheni kanye nejusi yezithelo.Indlela yokukhetha incike emikhubeni yomuntu siqu yonjiniyela.Ekuzinzeni kweziphuzo zobisi, i-CMC ifake isandla kakhulu.
Imikhiqizo ye-CMC ene-viscosity ephezulu inendawo enkulu yokufaka isicelo.Uma kuqhathaniswa nesitashi, i-guar gum, i-xanthan gum neminye imikhiqizo, ukuzinza kwe-CMC kusesobala, ikakhulukazi emikhiqizweni yenyama, inzuzo yokugcina amanzi ye-CMC isobala kakhulu!Phakathi kokuqiniswa okufana no-ayisikhilimu, i-CMC nayo iyisinqumo esihle.
Izinkomba eziyinhloko zokukala ikhwalithi ye-CMC yi-degree of substitution (DS) nobumsulwa.Ngokuvamile, izakhiwo ze-CMC zihlukile uma i-DS ihlukile;izinga lokushintsha liphakeme, kuqina ukuncibilika, kanye nokuba sobala nokuzinza kwesixazululo.Ngokwemibiko, ukucaca kwe-CMC kungcono uma izinga lokushintshwa liyi-0.7-1.2, futhi i-viscosity yesisombululo sayo esinamanzi inkulu kakhulu lapho inani le-pH liyi-6-9.
Ukuze kuqinisekiswe ikhwalithi yayo, ngaphezu kokukhethwa komenzeli wokufaka i-etherification, ezinye izici ezithinta izinga lokushintsha nobumsulwa nazo kufanele zicatshangelwe, njengobudlelwane phakathi kwenani le-alkali ne-etherification ejenti, isikhathi sokufaka i-etherification, okuqukethwe kwamanzi uhlelo, izinga lokushisa, inani le-DH, isixazululo Ukugxila nosawoti njll.
Izinga lemikhiqizo eqediwe ye-CMC ikakhulukazi lincike kwisixazululo somkhiqizo.Uma isixazululo somkhiqizo sicacile, kunezinhlayiya ezimbalwa zejeli, imicu yamahhala, namabala amnyama okungcola, kuqinisekiswa ngokuyisisekelo ukuthi izinga le-CMC lihle.Uma isisombululo sishiywe izinsuku ezimbalwa, isisombululo asibonakali.Imhlophe noma i-turbid, kodwa isacacile kakhulu, lowo ngumkhiqizo ongcono!
Isikhathi sokuthumela: Dec-14-2022