1. Umsebenzi oyinhloko we-cellulose ether
Odakeni oseluxubile, i-cellulose ether iyisengezo esiyinhloko esingezwa ngenani eliphansi kakhulu kodwa singathuthukisa kakhulu ukusebenza kodaka olumanzi futhi sithinte ukusebenza kokwakhiwa kodaka.
2. Izinhlobo zama-cellulose ethers
Ukukhiqizwa kwe-cellulose ether kwenziwa ikakhulukazi ngemicu yemvelo ngokusebenzisa ukuchithwa kwe-alkali, ukusabela ngokuxhunyelelwa (i-etherification), ukugeza, ukomisa, ukugaya nezinye izinqubo.
Ngokusho kwezinto eziyinhloko zokusetshenziswa, izintambo zemvelo zingahlukaniswa zibe: i-cotton fiber, i-cedar fiber, i-beech fiber, njll. Iziqu zabo ze-polymerization ziyahlukahluka, ezithinta i-viscosity yokugcina yemikhiqizo yabo. Njengamanje, abakhiqizi abakhulu be-cellulose basebenzisa i-cotton fiber (ngomkhiqizo we-nitrocellulose) njengento eyinhloko eluhlaza.
Ama-cellulose ether angahlukaniswa abe ionic ne-nonionic. Uhlobo lwe-ionic ikakhulukazi luhlanganisa usawoti we-carboxymethyl cellulose, kanti uhlobo olungezona i-ionic ikakhulukazi luhlanganisa i-methyl cellulose, i-methyl hydroxyethyl (propyl) cellulose, i-hydroxyethyl cellulose, njll.
Njengamanje, ama-cellulose ether asetshenziswa odakeni oseluxutshiwe ikakhulukazi i-methyl cellulose ether (MC), i-methyl hydroxyethyl cellulose ether (MHEC), i-methyl hydroxypropyl cellulose ether (MHPG), i-hydroxypropyl Methyl cellulose ether (HPMC). Ngodaka oluxutshwe ngomumo, ngenxa yokuthi i-ionic cellulose (usawoti we-carboxymethyl cellulose) ayizinzile lapho kukhona i-calcium ions, ayivamile ukusetshenziswa emikhiqizweni exutshwe ngomumo esebenzisa usimende, i-lime e-slaked, njll njengezinto zokuhlanganisa. Kwezinye izindawo e-China, usawoti we-carboxymethyl cellulose usetshenziswa njengesithako semikhiqizo ethile yasendlini ecutshungulwa ngesitashi esishintshiwe njengento eyinhloko yokufaka usimende kanye nempushana ye-Shuangfei njengesigcwalisi. Lo mkhiqizo ujwayele ukuba nesikhunta futhi awumelani namanzi, futhi manje uyaqedwa. I-Hydroxyethyl cellulose iphinde isetshenziswe kweminye imikhiqizo eseyimiksiwe, kodwa inesabelo semakethe esincane kakhulu.
3. Izinkomba zokusebenza eziyinhloko ze-cellulose ether
(1) Ukuncibilika
I-Cellulose iyinhlanganisela ye-polyhydroxy polymer engancibiliki noma incibilike. Ngemuva kwe-etherification, i-cellulose iyancibilika emanzini, ixube isixazululo se-alkali kanye ne-organic solvent, futhi ine-thermoplasticity. I-Solubility ikakhulukazi incike ezintweni ezine: okokuqala, ukuncibilika kuyahlukahluka nge-viscosity, i-viscosity ephansi, i-solubility enkulu. Okwesibili, izici zamaqembu ezethulwe ohlelweni lwe-etherification, iqembu elikhulu elethulwa, i-solubility ephansi; lapho iqembu elethula i-polar, kuba lula ukuthi i-cellulose ether incibilike emanzini. Okwesithathu, izinga lokushintshwa kanye nokusatshalaliswa kwamaqembu e-etherified kuma-macromolecules. Ama-ether amaningi e-cellulose angancibilika kuphela emanzini ngaphansi kwezinga elithile lokushintsha. Okwesine, izinga le-polymerization ye-cellulose ether, izinga eliphezulu le-polymerization, izinga lokuncibilika kancane; i-degree ephansi ye-polymerization, ububanzi bezinga lezinga lokushintsha elingancibilika emanzini.
(2) Ukugcinwa kwamanzi
Ukugcinwa kwamanzi kuwumsebenzi obalulekile we-cellulose ether, futhi kuwukusebenza ukuthi abakhiqizi abaningi be-powder eyomile basekhaya, ikakhulukazi labo abasezifundeni eziseningizimu ezinokushisa okuphezulu, banake. Izinto ezithinta umphumela wokugcina amanzi wodaka zihlanganisa inani le-cellulose ether engeziwe, i-viscosity, ukucoleka kwezinhlayiyana kanye nezinga lokushisa lendawo yokusebenzisa. Ukuphakama kwenani le-cellulose ether engeziwe, kuba ngcono umphumela wokugcina amanzi; i-viscosity enkulu, ngcono umphumela wokugcina amanzi; uma izinhlayiya zibe zinhle, kuba ngcono umphumela wokugcina amanzi.
(3) I-Viscosity
I-viscosity iyipharamitha ebalulekile yemikhiqizo ye-cellulose ether. Njengamanje, abakhiqizi be-cellulose ether abahlukene basebenzisa izindlela ezahlukene nezinsimbi zokukala i-viscosity. Ngomkhiqizo ofanayo, imiphumela ye-viscosity elinganiswa ngezindlela ezahlukene ihluke kakhulu, futhi eminye inomehluko ophindwe kabili. Ngakho-ke, lapho uqhathanisa i-viscosity, kufanele yenziwe phakathi kwezindlela ezifanayo zokuhlola, kufaka phakathi izinga lokushisa, i-rotor, njll.
Ngokuvamile, ukuphakama kwe-viscosity, kuba ngcono umphumela wokugcina amanzi. Kodwa-ke, ukuphakama kwe-viscosity, ukuphakama kwesisindo samangqamuzana e-cellulose ether, futhi ukwehla okuhambisanayo kokuncibilika kwawo kuzoba nomthelela omubi emandleni nokusebenza kokwakhiwa kodaka. Ukuphakama kwe-viscosity, kusobala kakhulu umphumela wokuqina odongeni, kodwa awulingani ngokuqondile. Ukuphakama kwe-viscosity, i-viscous yodaka olumanzi luyoba lukhulu. Ngesikhathi sokwakhiwa, kubonakala njengokunamathela ku-scraper nokunamathela okuphezulu ku-substrate. Kodwa akusizi ukwandisa amandla esakhiwo sodaka olumanzi ngokwalo. Ngesikhathi sokwakhiwa, ukusebenza kwe-anti-sag akubonakali. Ngokuphambene, i-viscosity ethile emaphakathi nephansi kodwa eshintshiwe ye-methyl cellulose ethers inokusebenza okuhle kakhulu ekuthuthukiseni amandla esakhiwo sodaka olumanzi.
(4) Ubuhle bezinhlayiya:
I-cellulose ether esetshenziselwa udaka oluxutshwe ngomumo iyadingeka ukuba ibe yimpushana, enokuqukethwe okuphansi kwamanzi, futhi ukucolisa kudinga futhi u-20% kuya ku-60% wesayizi wezinhlayiyana ukuze ube ngaphansi kuka-63 μm. Ukucoleka kuthinta ukunyibilika kwe-cellulose ether. Ama-coarse cellulose ethers ngokuvamile asesimweni sama-granules, okulula ukuwahlakaza nokuncibilika emanzini ngaphandle kwe-agglomeration, kodwa izinga lokuchithwa lihamba kancane, ngakho-ke alifanele ukusetshenziswa odakeni oluxutshwe ngomumo (eminye imikhiqizo yasekhaya i-flocculent; akulula ukuhlakazeka nokuncibilika emanzini, futhi othambekele ekwenzeni ikhekhe). Odakeni oseluxubile, i-cellulose ether ihlakazwa phakathi kwama-aggregates, izigcwalisi ezinhle nosimende nezinye izinto zikasimende. Impushana enhle ngokwanele kuphela engagwema i-cellulose ether agglomeration lapho ixutshwa namanzi. Uma i-cellulose ether yengezwa ngamanzi ukuze kuncibilike i-agglomeration, kunzima kakhulu ukuhlakazeka nokuhlakazeka.
(5) Ukuguqulwa kwe-cellulose ether
Ukuguqulwa kwe-cellulose ether kuyisandiso sokusebenza kwayo, futhi yingxenye ebaluleke kakhulu. Izakhiwo ze-cellulose ether zingathuthukiswa ukuze kwandiswe ukumanzisa kwayo, ukuhlakazeka, ukunamathela, ukujiya, i-emulsification, ukugcinwa kwamanzi kanye nezakhiwo zefilimu, kanye nokungagxili kwayo emafutheni.
4. Umthelela wezinga lokushisa elizungezile ekugcinweni kwamanzi odaka
Ukugcinwa kwamanzi kwe-cellulose ether kuncipha ngokunyuka kwezinga lokushisa. Ekusetshenzisweni kwezinto ezibonakalayo, udaka luvame ukusetshenziswa kuma-substrates ashisayo emazingeni okushisa aphezulu (ngaphezulu kuka-40°C) ezindaweni eziningi. Ukwehla kokugcinwa kwamanzi kubangele umthelela obonakalayo ekusebenzeni kanye nokumelana nokuqhekeka. Ukuncika kwayo emazingeni okushisa kusazoholela ekubeni buthakathaka kwezakhiwo zodaka, futhi kubaluleke kakhulu ukunciphisa umthelela wezici zokushisa ngaphansi kwalesi simo. Izindlela zokupheka zodaka zalungiswa ngokufanele, futhi izinguquko eziningi ezibalulekile zenziwa ekuphekeni kwesizini. Nakuba kwandisa umthamo (ifomula yasehlobo), ukusebenza nokumelana nokuqhekeka akukakwazi ukuhlangabezana nezidingo zokusetshenziswa, okudinga ukwelashwa okukhethekile kwe-cellulose ether, njengokwandisa izinga le-etherification, njll., ukuze umphumela wokugcina amanzi ube kufinyelelwe ezingeni lokushisa eliphezulu ngokuqhathaniswa. Igcina umphumela ongcono uma iphezulu, ukuze inikeze ukusebenza okungcono ezimweni ezinzima.
5. Faka isicelo odakeni oluxutshwe ngomumo
Ngodaka oluxutshwe ngomumo, i-cellulose ether idlala indima yokugcina amanzi, ukuqina nokuthuthukisa ukusebenza kokwakhiwa. Ukusebenza kahle kokugcinwa kwamanzi kuqinisekisa ukuthi udaka ngeke lubangele ukuthungathwa kwesihlabathi, impushana kanye nokunciphisa amandla ngenxa yokushoda kwamanzi kanye nokungagcwaliswa kahle kwamanzi. Umphumela wokujiya uthuthukisa kakhulu amandla esakhiwo sodaka olumanzi. Ukwengezwa kwe-cellulose ether kungathuthukisa kakhulu i-viscosity emanzi yodaka olumanzi, futhi kube ne-viscosity enhle kuma-substrates ahlukahlukene, ngaleyo ndlela kuthuthukise ukusebenza kodonga lodaka olumanzi futhi kunciphise imfucuza. Ngaphezu kwalokho, indima ye-cellulose ether emikhiqizweni ehlukene nayo ihlukile. Isibonelo, kuma-adhesives we-tile, i-cellulose ether ingandisa isikhathi sokuvula futhi ilungise isikhathi; odakeni lokufafaza ngomshini, lungathuthukisa amandla esakhiwo sodaka olumanzi; ekuzilinganiseni, kungavimbela ukuhlaliswa, Ukuhlukaniswa kanye nokuhlukaniswa. Ngakho-ke, njengesengezo esibalulekile, i-cellulose ether isetshenziswa kabanzi ku-powder mortar omile.
Isikhathi sokuthumela: Jan-11-2023