Hydroxypropyl Methyl Cellulose (HPMC), eo hape e tsejoang ka lebitso la khoebo hypromellose, ke polymer ea maiketsetso e nkiloeng ho selulose ea tlhaho. Mohloli oa mantlha oa selulose bakeng sa tlhahiso ea HPMC hangata ke makhasi a lehong kapa k'hothone. Ts'ebetso ea tlhahiso e kenyelletsa ho fetola selulose ka lik'hemik'hale ka etherification, ho hlahisa lihlopha tsa hydroxypropyl le methyl mokokotlong oa cellulose.

Tlhahiso ea HPMC e kenyelletsa mehato e mengata:

1. Ho ntšoa ha Cellulose:
   • Selulose e fumanoa mehloling ea limela, haholo-holo makhasi a lehong kapa k'hothone. Selulose e ntšoa ebe e hloekisoa ho etsa makhasi a cellulose.
2. Alkalization:
   • Sehlahisoa sa cellulose se phekoloa ka tharollo ea alkaline, hangata sodium hydroxide (NaOH), ho kenya tšebetsong lihlopha tsa hydroxyl ka ketane ea cellulose.
3. Etherification:
   • Etherification ke mohato oa bohlokoa tlhahisong ea HPMC. The alkalized cellulose e arajoa ka propylene oxide (bakeng sa lihlopha tsa hydroxypropyl) le methyl chloride (bakeng sa lihlopha tsa methyl) ho hlahisa lihlopha tsena tsa ether mokokotlong oa cellulose.
4. Ho Neutralization le Ho Hlatsoa:
   • Sephetho se fetotsoeng selulose, eo hona joale e leng Hydroxypropyl Methyl Cellulose, e kena ts'ebetsong ea ho se nke lehlakore ho tlosa alkali leha e le efe e setseng. Joale e hlatsuoa hantle ho tlosa litšila le lihlahisoa.
5. Ho omisa le ho sila:
   • Selulose e fetotsoeng 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.

Sehlahisoa sa HPMC se hlahisoang ke phofo e tšoeu kapa e sa bosoeu e nang le likhato tse fapaneng tsa hydroxypropyl le methyl substitution. Thepa e khethehileng ea HPMC, joalo ka solubility ea eona, viscosity, le litšobotsi tse ling tsa ts'ebetso, li itšetlehile ka tekanyo ea ho kenya sebaka le ts'ebetso ea tlhahiso.

Ho bohlokoa ho hlokomela hore HPMC ke polymer ea semi-synthetic, mme leha e tsoa ho selulose ea tlhaho, e ba le liphetoho tse kholo tsa lik'hemik'hale nakong ea ts'ebetso ea tlhahiso ho fihlela thepa eo e e batlang bakeng sa lits'ebetso tse fapaneng tsa indasteri.