Hydroxypropyl methylcellulose (HPMC) bụ ihe dị mkpa semi-synthetic cellulose ether compound, nke a na-ejikarị na nkà mmụta ọgwụ, ihe ụlọ, nri, mkpuchi na ụlọ ọrụ ndị ọzọ. HPMC nwere ezigbo thickening, emulsification, film-akpụ, moisturizing, stabilization na ndị ọzọ Njirimara, ya mere ọ nwere mkpa ngwa uru n'ọtụtụ ubi. Ihe ndị bụ isi maka imepụta HPMC gụnyere cellulose, sodium hydroxide, propylene oxide, methyl chloride na mmiri.
1. Cellulose
Cellulose bụ isi akụrụngwa akụrụngwa nke HPMC, nke a na-enwetakarị site na eriri osisi eke dị ka owu na osisi. Cellulose bụ polymer organic nke kachasị ukwuu n'ụwa. Ọdịdị molekụla ya bụ polysaccharide nwere ogologo yinye nke nkeji glucose jikọtara ya na njikọ β-1,4-glycosidic. Cellulose n'onwe ya enweghị ike ịsacha na mmiri ma ọ nweghị ezigbo mmeghachi omume kemịkal. Ya mere, a na-achọrọ usoro mgbanwe nke kemịkalụ iji kwalite solubility ya na ọrụ ya iji kwadebe ngwaahịa ether cellulose dị iche iche.
2. Sodium hydroxide (NaOH)
Sodium hydroxide, nke a makwaara dị ka soda caustic, bụ ogige alkaline siri ike nke na-arụ ọrụ dị mkpa dị ka alkalizer na usoro mmepụta nke HPMC. N'oge mmalite nke mmepụta, cellulose na-emeghachi omume na ngwọta sodium hydroxide iji mee ka ìgwè hydroxyl dị na cellulose molecular chain, si otú ahụ na-enye saịtị mmeghachi omume maka mmeghachi omume etherification na-esote. A na-akpọkwa nzọụkwụ a "mmeghachi omume alkalization". Cellulose alkalized na-enweta ụfọdụ mgbanwe nhazi, na-eme ka ọ dịkwuo mfe iji reagents kemịkalụ na-esote (dị ka propylene oxide na methyl chloride).
3. Propylene oxide (C3H6O)
Propylene oxide bụ otu n'ime ihe ndị na-eme ka ahụ dị mkpa na mmepụta HPMC, nke a na-ejikarị eme ka otu hydroxyl dị na cellulose ghọọ otu hydroxypropyl. Kpọmkwem, cellulose alkalized na-emeghachi omume na propylene oxide n'okpuru ọnọdụ okpomọkụ na ọnọdụ nrụgide, na otu epoxy na-arụ ọrụ na propylene oxide na-ejikọta ya na cellulose molekul site na mmeghachi omume mmeghe na-emepe mgbanaka iji mepụta ihe nnọchi hydroxypropyl. Usoro a na-enye HPMC ezigbo mmiri solubility na ike ịgba.
4. Methyl chloride (CH3Cl)
Methyl chloride bụ ihe ọzọ dị mkpa etherifying a na-eji eme ka otu hydroxyl nke cellulose ghọọ otu methoxyl. Methyl chloride na-emeghachi omume na otu hydroxyl na agbụ molekul cellulose site na mmeghachi omume nucleophilic iji mepụta methyl cellulose. Site na mmeghachi omume methylation a, HPMC na-enweta ezigbo hydrophobicity, karịsịa na-egosi ezigbo solubility na ụfọdụ ihe mgbaze organic. Na mgbakwunye, iwebata ndị otu methoxy na-eme ka ihe na-emepụta ihe nkiri na nkwụsi ike nke HPMC dịkwuo mma.
5. Mmiri
Mmiri, dị ka ihe mgbaze na mmeghachi omume mmeghachi omume, na-aga na usoro mmepụta HPMC dum. Na mmeghachi omume alkalization na etherification, mmiri ọ bụghị nanị na-enyere aka igbari sodium hydroxide ma dozie ọnọdụ hydration nke cellulose, ma na-ekerekwa òkè na nhazi nke mmeghachi omume okpomọkụ iji hụ na njikwa okpomọkụ n'oge usoro mmeghachi omume. Ịdị ọcha nke mmiri na-enwe mmetụta dị mkpa na àgwà HPMC, na mmiri dị ọcha nke deionized ma ọ bụ mmiri na-ekpo ọkụ na-achọkarị.
6. Organic mgbaze
Na usoro mmepụta nke HPMC, ụfọdụ usoro usoro nwekwara ike ịchọ iji ụfọdụ ihe mgbaze organic, dị ka methanol ma ọ bụ ethanol. A na-eji ihe mgbaze ndị a mgbe ụfọdụ iji dozie viscosity nke usoro mmeghachi omume, belata nguzobe nke ngwaahịa mmeghachi omume, ma ọ bụ kwalite mmeghachi omume kemịkalụ kpọmkwem. Nhọrọ nke ihe mgbaze organic kwesịrị ikpebi dịka mkpa nke usoro mmepụta na ntinye nke ngwaahịa ikpeazụ.
7. Ihe enyemaka ndị ọzọ
Na mgbakwunye na isi ihe ndị dị n'elu, na usoro mmepụta n'ezie, a pụrụ iji ụfọdụ ihe enyemaka na ihe mgbakwunye, dị ka catalysts, stabilizers, wdg. nke ikpeazụ ngwaahịa.
8. Isi nzọụkwụ nke usoro mmepụta
Enwere ike kewaa usoro isi usoro maka imepụta HPMC ụzọ atọ: alkalization, etherification na neutralization ọgwụgwọ. Nke mbụ, cellulose na-emeghachi omume na sodium hydroxide iji mepụta alkali cellulose. Mgbe ahụ, etherification na-apụta na mmeghachi omume nke alkali cellulose na propylene oxide na methyl chloride iji mepụta hydroxypropyl na methoxy dochie cellulose ethers. N'ikpeazụ, site neutralization ọgwụgwọ, ịsa, ihicha na ndị ọzọ usoro, HPMC ngwaahịa na kpọmkwem solubility, viscosity na ndị ọzọ e ji mara.
9. Mmetụta nke akụrụngwa akụrụngwa na arụmọrụ nke ngwaahịa HPMC
Isi mmalite akụrụngwa dị iche iche na ịdị ọcha nwere mmetụta dị ukwuu na ịdịmma na arụmọrụ nke HPMC ikpeazụ. Dịka ọmụmaatụ, ịdị ọcha na nkesa molekụla nke akụrụngwa cellulose ga-emetụta viscosity na solubility nke HPMC; Usoro onunu ogwu na mmeghachi omume nke propylene oxide na methyl chloride ga-ekpebi ogo hydroxypropyl na nnọchi methoxy, si otú a na-emetụta mmetụta na-abawanye na ihe na-emepụta ihe nkiri nke ngwaahịa ahụ. Ya mere, nhọrọ na njikwa mma nke akụrụngwa dị oke mkpa n'oge usoro mmepụta.
Ihe ndị bụ isi nke hydroxypropyl methylcellulose (HPMC) gụnyere cellulose, sodium hydroxide, propylene oxide, methyl chloride na mmiri. Site na usoro mmeghachi omume kemịkalụ dị mgbagwoju anya, a na-atụgharị akụrụngwa ndị a ka ọ bụrụ ihe na-arụ ọrụ nke nwere uru ngwa ngwa. Ngwa ngwa nke HPMC na-ekpuchi ọtụtụ ubi dịka ọgwụ, ihe ụlọ na nri. Ngwongwo anụ ahụ na kemịkal ya dị mma na-eme ka ọ dị mkpa n'ọtụtụ ụlọ ọrụ.
Oge nzipu: Sep-30-2024