Li-ether tsa seluloseke lelapa la li-polymer tse qhibilihang ka metsing tse tsoang ho cellulose, e leng polymer ea tlhaho e ngata ka ho fetisisa e fumanoang maboteng a sele ea limela. Li-polymer tsena tse fetotsoeng li na le mefuta e mengata ea lits'ebetso tsa indasteri le tsa khoebo, ho kenyeletsoa le ts'ebeliso ea kaho, meriana, lijo, litlolo le lipente. Ts'ebetso ea ho etsa li-ether tsa cellulose e kenyelletsa phetoho ea lik'hemik'hale ea cellulose ea tlhaho ho ntlafatsa ho qhibiliha ha eona, botsitso ba mocheso, taolo ea viscosity le ho tenyetseha ha ts'ebetso.
1. Lisebelisoa tse Tala: Cellulose ea Tlhaho
Thepa e tala ea mantlha e sebelisoang tlhahisong ea ether ea cellulose ke cellulose e hloekisitsoeng, eo hangata e fumanoang ho:
Letlalo la patsi (lehong le thata kapa lehong le bonolo)
Li-linters tsa k'hothone (mohloli o hloekileng haholo)
Cellulose ke polysaccharide e entsoeng ka liketane tse otlolohileng tsa diyuniti tsa β-D-glucose tse hokahantsweng ke dibonto tsa β-1,4-glycosidic. Dihlopha tsa hydroxyl (–OH) diyuniti tsa glucose di etsa hore cellulose e arabele haholo mme e lokele ho fetolwa ka dikhemikhale.
2. Tlhophiso ea Li-Ether tsa Cellulose
Li-ether tsa cellulose li rehelloa mabitso ho latela lintho tse nkeloang sebaka tse kentsoeng mokokotlong oa cellulose. Mefuta e tloaelehileng haholo e kenyelletsa:
Hydroxypropyl methylcellulose (HPMC)
Mofuta le tekanyo ea phetolo li khetholla litšobotsi tsa 'mele le tsa lik'hemik'hale tsa sehlahisoa sa ho qetela.
3. Likarabelo tsa Bohlokoa tsa Lik'hemik'hale Tlhahisong
Li-ether tsa cellulose li hlahisoa ke ho fetoha ha lihlopha tsa hydroxyl ho cellulose. Ts'ebetso e akaretsang e kenyelletsa liketso tse peli tse kholo tsa lik'hemik'hale:
3.1. Alkalization (Mohato oa ho Kenya Ts'ebetsong)
Mohato ona o lokisetsa cellulose bakeng sa etherification ka ho e fetola alkali cellulose:
Karabelo:
NaOH (sodium hydroxide) e roba dibopeho tsa haeterojene mme e ruruhisa difaeba tsa cellulose, e leng se eketsang phihlello.
Lihlopha tsa hydroxyl tse holim'a cellulose lia kenngoa tšebetsong ho etsa alkali cellulose.
3.2. Etherification (Karabelo ea ho Nkela Sebaka)
Selulose ea alkali e arabela le metsoako e itseng ea ho qhibilihisa, ho latela sehlahisoa se lakatsehang:
Methyl chloride (CH₃Cl) bakeng sa methyl cellulose
Ethylene oxide (C₂H₄O) kapa chloroethanol bakeng sa hydroxyethyl cellulose
Propylene oxide (C₃H₆O) bakeng sa lihlopha tsa hydroxypropyl
Sodium monochloroacetate bakeng sa carboxymethyl cellulose
Mohlala (sebopeho sa MC):
Mohlala (sebopeho sa CMC):
Tekanyo ea phetolo (DS - Tekanyo ea Phetolo) le mofuta oa sehlopha sa ether li khetholla ho qhibiliha, ho teteana, le boitšoaro ba mocheso ba ether ea cellulose e hlahisoang.
4. Ts'ebetso ea Tlhahiso ea Cellulose Ethers
Tlhahiso ea khoebo ea li-ether tsa cellulose hangata e latela sehlopha kapa ts'ebetso e tsoelang pele ka mehato e 'maloa e laoloang ka hloko:
Mohato oa 1: Ho Hloekisa Cellulose
Cellulose e tala e hloekisoa le ho soeufala ho tlosa lignin, hemicellulose le litšila.
E omisitsoe ebe e siloa hore e be phofo e ntle bakeng sa ho ntlafatsa ts'ebetso ea eona.
Mohato oa 2: Alkalization
Cellulose e kopanngoa le tharollo ea sodium hydroxide.
Mocheso o bolokoa pakeng tsa 20°C le 40°C ho laola ho sebetsa hape.
Mokhoa ona o fetola cellulose hore e be alkali cellulose.
Mohato oa 3: Karabelo ea Etherification
Moemeli o futhumatsang o eketsoa tlas'a khatello le mocheso o laoloang.
Maemo a karabelo (mocheso, nako, pH, le mahloriso a reagent) a ntlafalitsoe bakeng sa litlhaloso tsa sehlahisoa se reriloeng.
Lihlahisoa tse ling tse kang NaCl, methanol, kapa glycol lia thehoa, tse lokelang ho tlosoa hamorao.
Mohato oa 4: Ho se nke lehlakore
Alkali e sa arajoang e felisoa ka ho sebelisa li-acid tse kang acetic acid kapa hydrochloric acid.
Mohato ona o tsitsisa sehlahisoa mme o thibela liketso tse ling tse sa batleheng.
Mohato oa 5: Ho hlatsoa
Sehlahisoa se tala se hlatsuoa ka makhetlo a mangata ka metsi, joala, kapa asetone.
Sena se tlosa dihlahiswa tse setseng, di-reagent tse setseng, le matswai.
Ho sefa kapa ho centrifugation ho ka sebediswa ho arola dintho tse tiileng.
Mohato oa 6: Ho omisa
Kuku e metsi e omisoa ka har'a li-dryer tse potolohang, li-dryer tsa bethe tse nang le metsi, kapa li-dryer tsa lebanta.
Mocheso oa ho oma o laoloa ka hloko ho thibela ho senyeha.
Mohato oa 7: Ho Sila le ho Sila
Sehlahisoa se omisitsoeng se siloa hore e be phofo e tšesaane.
Kabo ea boholo ba likaroloana e lokisoa ho latela litlhoko tsa ts'ebeliso ea basebelisi ba ho qetela.
Mohato oa 8: Sephutheloana
Sehlahisoa sa ho qetela se pakoa ka mekotleng kapa lijaneng tse sa keneleng mongobo.
Maemo a polokelo a lokela ho ba a omileng le a pholileng ho boloka boleng.
5. Taolo ea Boleng le ho Etsa Lintho ka Tsela e Ikhethileng
Diparamente tsa boleng tse kang ho teteana, tekanyo ea ho nkeloa sebaka, mongobo, pH, le boholo ba likaroloana li lekoa ka mekhahlelo e mengata. Sehlahisoa se ka boela sa etsoa hore se be se ikhethileng bakeng sa:
Ho qhaqhoa ka potlako kapa ho lieha
Mekhahlelo e itseng ea viscosity (e tlase ho isa ho e phahameng)
Ho mamella letsoai
Kalafo ea bokaholimo (mohlala, ho kopanya bokaholimo bakeng sa ho lieha ho nosetsa)
6. Mehopolo ea Tikoloho
Tlhahiso ea li-ether tsa cellulose e kenyelletsa ho sebetsana le metsoako ea lintho tse phelang e feto-fetohang (VOCs), li-alkali le lihlahisoa tse ling. Bahlahisi ba nang le boikarabelo ba tsetela ho:
Mekhoa ea ho hapa le ho phekola VOC
Mekhoa ea ho hlatsoa le ho hlaphoheloa e koetsoeng
Ho lahla kapa ho sebelisa hape letsoai ka mokhoa o sireletsehileng
Lisebelisoa tsa ho omisa le ho sebetsana le tsona tse bolokang matla
Mekhoa e meng e sireletsang tikoloho le boqapi ba k'hemistri e tala li ntse li hlahlojoa ho etsa hore tlhahiso ea ether ea cellulose e tšoarelle haholoanyane.
7. Litšebeliso tsa Cellulose Ethers
Ka lebaka la thepa ea tsona e feto-fetohang (ho tenya, ho tsitsisa, ho tlama, ho etsa filimi, ho emulsifying, ho boloka metsi), li-ether tsa cellulose li sebelisoa ho:
7.1. Kaho
Likhomaretsi tsa thaele, li-render, li-plaster tsa samente, metsoako e iketsang
Lintho tse ntlafatsang ho boloka metsi le ho sebetsa hantle
7.2. Meriana
Li-binder le li-disintegrant tsa matlapa
Matrices a lokollotsoeng a laoloang
7.3. Indasteri ea Lijo
Lisebelisoa tsa ho tebisa ka lisoso, lijo tse tsoekere, le mekhoa e meng ea lebese
Lijo tse nang le lik'hilojule tse tlase li ka nkela mafura sebaka
7.4. Litlolo le Tlhokomelo ea Motho ka Mong
Litlolo, litlolo, li-shampoo le li-gel bakeng sa sebopeho le botsitso
7.5. Lipente le Liaparo
Li-modifiers tsa rheology ka pente e thehiloeng metsing
Lisebelisoa tse thibelang ho thella le ho ntlafatsa ho phunya
7.6. Ho Cheka Oli
Taolo ea tahlehelo ea mokelikeli seretseng sa ho cheka
Ho tlotsa ka hara maro a pshatlehang
Tlhahiso ea li-ether tsa cellulose ke ts'ebetso ea lik'hemik'hale e entsoeng ka hloko e fetolang cellulose ea tlhaho e ngata hore e be li-polymer tse sebetsang hantle. Ho tloha ho pulp ea lehong kapa ea k'hothone, ka alkalization le etherification, ho isa sehlahisoa sa ho qetela se hloekisitsoeng le se omisitsoeng, mohato o mong le o mong o ntlafalitsoe bakeng sa polokeho, katleho le boleng ba sehlahisoa. Lisebelisoa tsena tse feto-fetohang li bohlokoa haholo indastering e fapaneng, ka lebaka la motsoako oa tsona o ikhethang oa tlhaho le ts'ebetso ea maiketsetso. Ka ho hatisa ho ntseng ho hola lisebelisoa tse bolang le tse tšoarellang,Li-ether tsa cellulose li ntse li tsoela pele ho bapala karolo ea bohlokoa bokamosong ba k'hemistri e tala le thepa e tsoetseng pele.
Nako ea poso: Phupu-11-2025