Mokhoa oa ho etsa cellulose ether?

Mokhoa oa ho etsa cellulose ether?

Tlhahiso ea li-cellulose ethers e kenyelletsa ho fetola lik'hemik'hale cellulose ea tlhaho, eo hangata e nkiloeng ho makhasi a lehong kapa k'hothone, ka letoto la liphetoho tsa lik'hemik'hale. Mefuta e tloaelehileng haholo ea li-cellulose ethers e kenyelletsa Methyl Cellulose (MC), Hydroxyethyl Cellulose (HEC), Hydroxypropyl Methyl Cellulose (HPMC), Carboxymethyl Cellulose (CMC), le tse ling. Ts'ebetso e nepahetseng e ka fapana ho latela selulose ether e khethehileng e hlahisoang, empa mehato e akaretsang e tšoana. Mona ke kakaretso e nolofalitsoeng:

Mehato e akaretsang ea ho etsa Cellulose Ethers:

1. Mohloli oa Cellulose:

  • Thepa ea ho qala ke selulose ea tlhaho, hangata e fumanoang ho tloha makhasi a lehong kapa k'hothone. Selulose hangata e fumaneha ka mokhoa oa "purified cellulose pulp".

2. Alkalization:

  • Selulose e phekoloa ka tharollo ea alkaline, joalo ka sodium hydroxide (NaOH), ho kenya tšebetsong lihlopha tsa hydroxyl ka ketane ea cellulose. Mohato ona oa alkalization ke oa bohlokoa bakeng sa nts'etsopele e tsoelang pele.

3. Etherification:

  • Selulose e nang le alkalize e kenngoa ka etherification, moo lihlopha tse fapaneng tsa ether li kenngoa mokokotlong oa cellulose. Mofuta o khethehileng oa sehlopha sa ether se hlahisitsoeng (methyl, hydroxyethyl, hydroxypropyl, carboxymethyl, joalo-joalo) e itšetlehile ka ether ea cellulose e lakatsehang.
  • Ts'ebetso ea etherification e kenyelletsa karabelo ea cellulose ka li-reagents tse nepahetseng, joalo ka:
    • Bakeng sa Methyl Cellulose (MC): Kalafo ka dimethyl sulfate kapa methyl chloride.
    • Bakeng sa Hydroxyethyl Cellulose (HEC): Kalafo ka ethylene oxide.
    • Bakeng sa Hydroxypropyl Methyl Cellulose (HPMC): Kalafo ka propylene oxide le methyl chloride.
    • Bakeng sa Carboxymethyl Cellulose (CMC): Kalafo ka sodium chloroacetate.

4. Ho Neutralization le Ho Hlatsoa:

  • Ka mor'a etherification, sephetho sa selulose se hlahisoang hangata ha se nke lehlakore ho tlosa alkali efe kapa efe e setseng. Joale sehlahisoa se hlatsuoa ho felisa litšila le lihlahisoa.

5. Ho omisa le ho sila:

  • Ether ea cellulose e omisitsoe ho tlosa mongobo o feteletseng ebe e kenngoa ka phofo e ntle. Boholo ba likaroloana bo ka laoloa ho latela ts'ebeliso e reriloeng.

6. Taolo ea Boleng:

  • Sehlahisoa sa ho qetela sa cellulose ether se feta litekong tsa taolo ea boleng ho netefatsa hore se kopana le litlhaloso tse ikhethileng, ho kenyelletsa le viscosity, mongobo, kabo ea boholo ba likaroloana, le thepa e 'ngoe e amehang.

Ke habohlokoa ho hlokomela hore tlhahiso ea cellulose ethers e etsoa ke baetsi ba khethehileng ba sebelisang mekhoa e laoloang. Maemo a ikhethileng, li-reagents, le lisebelisoa tse sebelisoang li ka fapana ho latela thepa e lakatsehang ea cellulose ether le ts'ebeliso e reriloeng. Ho feta moo, mehato ea polokeho e bohlokoa nakong ea ts'ebetso ea phetoho ea lik'hemik'hale.


Nako ea poso: Jan-01-2024