Hydroxyethyl cellulose (HEC) ke ether e seng ea ionic cellulose e sebelisoang haholo kahong, ho roala, peterole, lik'hemik'hale tsa letsatsi le letsatsi le masimo a mang. E na le botenya bo botle, ho emisoa, ho qhalakanngoa, emulsification, filimi-forming, colloid e sireletsang le lisebelisoa tse ling, 'me ke ntho ea bohlokoa e teteaneng le e tsitsitseng.
1. Tokisetso ea lisebelisoa tse tala
Ntho e ka sehloohong e tala ea hydroxyethyl cellulose ke cellulose ea tlhaho. Hangata cellulose e ntšoa ka lehong, k'hothone kapa limela tse ling. Mokhoa oa ho ntša cellulose o batla o le bonolo, empa o hloka bohloeki bo phahameng ho netefatsa ts'ebetso ea sehlahisoa sa ho qetela. Ka lebaka lena, mekhoa ea lik'hemik'hale kapa ea mechine e atisa ho sebelisoa pele ho phekoloa selulose, ho kenyelletsa le ho senya, ho senya, ho hloekisa le mehato e meng ea ho tlosa litšila le likaroloana tse seng tsa cellulose.
2. Kalafo ea alkalization
Kalafo ea alkalization ke mohato oa bohlokoa ts'ebetsong ea tlhahiso ea hydroxyethyl cellulose. Morero oa mohato ona ke ho kenya tšebetsong sehlopha sa hydroxyl (-OH) ho ketane ea limolek'hule tsa cellulose ho thusa karabelo e latelang ea etherification. Sodium hydroxide (NaOH) tharollo hangata e sebelisoa e le alkalizing agent. Mokhoa o ikhethileng ke: kopanya selulose le tharollo ea sodium hydroxide ho ruruha ka botlalo le ho hasanya selulose tlas'a maemo a alkaline. Ka nako ena, lihlopha tsa hydroxyl ka limolek'hule tsa cellulose li ba mafolofolo haholoanyane, li itokisetsa karabelo e latelang ea etherification.
3. Karabelo ea Etherification
Etherification reaction ke mohato oa mantlha tlhahisong ea hydroxyethyl cellulose. Tshebetso ena ke ho hlahisa ethylene oxide (eo hape e tsejoang e le ethylene oxide) ho selulose ka mor'a phekolo ea alkalinization, le ho itšoara ka lihlopha tsa hydroxyl ka limolek'hule tsa cellulose ho hlahisa hydroxyethyl cellulose. Hangata karabelo e etsoa ka mochini o koetsoeng, mocheso oa karabelo hangata o laoloa ho 50-100 ° C, 'me nako ea karabelo e tloha ho lihora tse' maloa ho isa ho lihora tse fetang leshome. Sehlahisoa sa ho qetela sa karabelo ke karoloana ea hydroxyethylated cellulose ether.
4. Ho se nke lehlakore le ho hlatsoa
Ka mor'a hore karabelo ea etherification e phethoe, li-reactants hangata li na le palo e kholo ea alkali e sa sebetseng le lihlahisoa. E le hore u fumane sehlahisoa se hloekileng sa hydroxyethyl cellulose, phekolo ea neutralization le ho hlatsoa e tlameha ho etsoa. Hangata, dilute acid (e kang dilute hydrochloric acid) e sebelisoa ho fokotsa masala a alkali ka karabelo, ebe li-reactants li hlatsuoa khafetsa ka metsi a mangata ho tlosa litšila tse qhibilihang ke metsi le lihlahisoa. Selulose e hlatsoitsoeng ea hydroxyethyl e teng ka sebopeho sa kuku ea sefene e metsi.
5. Ho felloa ke metsi 'meleng le ho Omisa
Kaka e metsi ka mor'a ho hlatsoa e na le metsi a mangata 'me e hloka ho felloa ke metsi le ho omisoa ho fumana sehlahisoa sa phofo sa hydroxyethyl cellulose. Hangata dehydration e etsoa ka vacuum filtration kapa karohano ea centrifugal ho tlosa boholo ba metsi. Ka mor'a moo, kuku e metsi e romelloa lisebelisoa tsa ho omisa bakeng sa ho omisa. Lisebelisoa tse tloaelehileng tsa ho omisa li kenyelletsa li-drum dryer, li-flash dryer le li-spray dryer. Thempereichara ea ho omisa hangata e laoloa ho 60-120 ℃ ho thibela mocheso o feteletseng hore o se ke oa baka denaturation ea sehlahisoa kapa ho senyeha ha ts'ebetso.
6. Ho sila le ho Hlakola
Selulose se omisitsoeng sa hydroxyethyl hangata ke sekoahelo se seholo kapa thepa ea granular. E le ho nolofatsa ts'ebeliso le ho ntlafatsa ho senyeha ha sehlahisoa, se hloka ho siloa le ho hlahlojoa. Hangata ho sila ho sebelisa grinder ea mochini ho sila litene tse kholo ho etsa phofo e ntle. Ho hlahloba ke ho arola likaroloana tse mahoashe tse sa fihlelle boholo bo hlokahalang ka phofo e ntle ka li-skrini tse nang le li-apertures tse fapaneng ho netefatsa hore ho na le fineness e lekanang ea sehlahisoa sa ho qetela.
7. Sehlahisoa sa ho paka le ho boloka
Sehlahisoa sa hydroxyethyl selulose ka mor'a ho sila le ho hlahloba se na le mokelikeli o itseng le dispersibility, tse loketseng ho sebelisoa ka ho toba kapa ho tsoela pele ho sebetsa. Sehlahisoa sa ho qetela se hloka ho phutheloa le ho bolokoa ho thibela mongobo, tšilafalo kapa oxidation nakong ea lipalangoang le polokelo. Lisebelisoa tsa ho paka tse thibelang mongobo le tse thibelang oxidation joalo ka mekotla ea foil ea aluminium kapa mekotla e nang le likarolo tse ngata hangata e sebelisoa bakeng sa ho paka. Ka mor'a ho phuthela, sehlahisoa se lokela ho bolokoa sebakeng se pholileng le se omileng, ho qoba letsatsi le tobileng le mocheso o phahameng le maemo a mongobo o phahameng ho netefatsa ts'ebetso ea eona e tsitsitseng.
Ts'ebetso ea tlhahiso ea hydroxyethyl cellulose haholo-holo e kenyelletsa ho lokisoa ha lisebelisoa tse tala, kalafo ea alkalization, karabelo ea etherification, neutralization le ho hlatsoa, ho felloa ke metsi le ho omisa, ho sila le ho hlahloba, le ho paka le ho boloka sehlahisoa sa ho qetela. Mohato o mong le o mong o na le litlhoko tsa oona tse khethehileng tsa ts'ebetso le lintlha tsa taolo. Maemo a karabelo le litlhaloso tsa ts'ebetso li hloka ho laoloa ka thata nakong ea ts'ebetso ea tlhahiso ho netefatsa boleng le ts'ebetso e tsitsitseng ea sehlahisoa. Sesebelisoa sena sa polymer se sebetsang ka bongata se na le lits'ebetso tse fapaneng tlhahisong ea indasteri le bophelo ba letsatsi le letsatsi, se bonts'ang bohlokoa ba sona bo ke keng ba nkeloa sebaka.
Nako ea poso: Aug-21-2024