Njirimara kemịkalụ nke HPMC

Hydroxypropyl Methylcellulose (HPMC)bụ cellulose ether nke na-abụghị ionic, nke bụ ngwaahịa e ji kemịkalụ gbanwee site na mmeghachi omume nke cellulose eke na propylene oxide na methyl chloride mgbe alkalization gasịrị. HPMC nwere ezigbo nkwụsi ike anụ ahụ na kemịkalụ ma ejiri ya mee ihe nke ukwuu na ọgwụ, ihe owuwu ụlọ, nri, ihe ịchọ mma na ngalaba ndị ọzọ. Njirimara kemịkalụ ya bụ ndị a:

1. Àgwà nhazi molekụla

Ọkpụkpụ HPMC bụ isi sitere na cellulose eke, nke a na-emepụta site na nkeji glucose jikọtara site na njikọ β-1,4-glycosidic iji mepụta agbụ macromolecular linear. Ntinye nke otu hydroxypropyl na methoxy na-anọchi otu hydroxyl (-OH) na agbụ molekul cellulose, si otú a na-enye ya ihe pụrụ iche. Ogo nnọchi a (ya bụ, ogo nnọchi nke otu methoxy na hydroxypropyl) nwere mmetụta dị mkpa na ịgbaze, njirimara gel na nkwụsi ike nke HPMC.

2. Mmiri na-agbaze

HPMC bụ polima nkịtị nke na-agbaze na mmiri nke na-abụghị ionic nke nwere ike ịgbaze ngwa ngwa na mmiri oyi ma mepụta ngwọta colloidal doro anya ma ọ bụ translucent. Agbanyeghị, na mmiri ọkụ, HPMC adịghị mfe ịgbaze ma ga-emepụta jel na okpomọkụ dị elu. Njirimara jel a nke a na-agbanwe agbanwe bụ otu n'ime ihe ndị dị mkpa maka anụ ahụ na kemịkalụ nke HPMC. Na mgbakwunye na mmiri, enwere ike ịgbaze HPMC na ụfọdụ ihe mgbaze organic polar, dị ka ihe mgbaze ethanol na mmiri agwakọtara, dimethylformamide, wdg.

3. Nkwụsi ike na njikọta okpomọkụ

HPMC nwere ezigbo nkwụsi ike okpomọkụ. Ka okpomọkụ na-arị elu, agbụ molekul HPMC dị na mmiri mmiri ga-abanye n'ime mmiri iji mepụta nhazi netwọk atọ, mgbanwe site na mmiri gaa na jel ga-eme. Okpomọkụ gelation dabere na ọdịnaya na ibu molekul nke ihe ndị na-anọchi ya. N'ozuzu, HPMC nwere nnukwu hydroxypropyl ọdịnaya nwere okpomọkụ gelation dị elu, ebe HPMC nwere nnukwu methoxy ọdịnaya nwere obere okpomọkụ gelation.

A na-agbanwegharị gel ahụ, gel ahụ ga-agbazekwa ọzọ ka ọ bụrụ mmiri mmiri mgbe ọ jụrụ oyi. Ihe pụrụ iche a na-akpọ thermogel na-eme ka HPMC bụrụ ihe a na-eji ewepụta ihe na-adịgide adịgide n'ụlọ ọrụ ọgwụ ma jiri ya mee ihe n'ụlọ ọrụ ihe owuwu iji melite arụmọrụ owuwu nke moto.

4. nkwụsi ike pH

HPMC na-ejigide ezigbo nkwụsi ike na oke pH nke 3~11. Oke nkwụsi ike pH a sara mbara na-enye ohere iji ya n'ọtụtụ ebe na-enweghị mmebi ma ọ bụ mmiri ozuzo. Mgbe uru pH dị ala karịa 3 ma ọ bụ karịa 11, ngwọta ahụ nwere ike imebi ma ọ bụ kpalite n'ihi oke mkpokọta nke ion hydrogen ma ọ bụ ion hydroxide, nke na-ebute mbelata arụmọrụ.

5. Mmeghachi omume Kemịkalụ

N'ihi ọnụnọ nke ụfọdụ otu hydroxyl a na-edochighị na molekul HPMC, ọ ka na-ejigide ọrụ kemịkalụ ụfọdụ ma nwee ike ịnweta mmeghachi omume ndị a:

Mmeghachi omume Esterification: N'ọnọdụ kwesịrị ekwesị, HPMC nwere ike imeghachi omume na acyl chlorides, anhydrides, wdg iji mepụta esters;

Mmeghachi omume nke mgbanwe: Otu hydroxyl fọdụrụnụ nwere ike ịnọgide na-emeghachi omume na ihe ndị na-eme ka ihe dị n'ime mmiri (dịka epoxides) iji gbanwee ọkwa nnọchi na arụmọrụ nke HPMC;

Mmeghachi omume oxidation: Ọ bụrụ na e nwere ihe ndị na-eme ka oxidants sie ike (dịka potassium permanganate, sodium hypochlorite), usoro molekul nke HPMC nwere ike imebi, nke na-eme ka viscosity belata;

Mmeghachi omume nke hydrolysis: N'okpuru ọrụ nke asịd siri ike ma ọ bụ ntọala siri ike, a pụrụ ịgbaze hydroxypropyl na methoxy n'akụkụ agbụ, na-akpata mgbanwe na nhazi molekul na mmebi arụmọrụ.

N'ozuzu, n'okpuru ọnọdụ ngwa nkịtị, ihe kemịkalụ nke HPMC kwụsiri ike.

6. Mmebi nke ihe ndị dị ndụ

A na-esi na cellulose eke enweta HPMC, ya mere enwere ike imebi ya ka ọ bụrụ obere shuga molekul n'ime gburugburu ebe obibi (dịka site n'ọrụ nke obere nje), ma mechaa gbazee ka ọ bụrụ carbon dioxide na mmiri. Ezigbo mmebi a na-eme ka HPMC mezuo ihe achọrọ maka ihe ndị na-adịghị ize ndụ gburugburu ebe obibi.

7. Ndakọrịta na ihe ndị ọzọ

Dịka polima na-abụghị ionic, HPMC nwere ezigbo ndakọrịta na ọtụtụ ihe mgbakwunye ionic ma ọ bụ nke na-abụghị ionic (dịka polima ndị ọzọ, surfactants, thickeners, wdg). Karịsịa na sistemụ nhazi, ọ nwere ike ịrụ ọrụ na ọtụtụ ihe eji eme ọgwụ, ihe oriri, agba, wdg na-enweghị mmiri ozuzo ma ọ bụ nhazi.

Ọ ga-emetụta nkwụsi ike nke HPMC n'ebe nwere nnukwu njupụta elektrọl, oke nnu na-adịghị n'ime ahụ nwere ike ime ka viscosity nke ngwọta ahụ belata ma ọ bụ ọbụna mee ka ọ daa.

8. Nguzogide enzyme

Ma e jiri ya tụnyere cellulose eke,HPMCo nwere ike iguzogide cellulase nke ọma n'ihi mgbanwe nke ụfọdụ otu hydroxyl, ọ naghịkwa agbaze ngwa ngwa site na enzymes nkịtị. Njirimara a na-enye ya uru nke iwepụ ọgwụ n'oge na-adịghị anya na gburugburu afọ.

Hydroxypropyl methylcellulose (HPMC) bụ ihe e ji kemịkalụ mepụta nke e ji kemịkalụ gbanwee, nke nwere ezigbo mmiri na-agbaze, ihe na-eme ka ọ dị nro, pH kwụsie ike, nkwụsi ike kemịkalụ na ihe ndị na-emebi emebi. N'ihi nhazi ya pụrụ iche na ihe ndị metụtara kemịkalụ, a na-ejikarị HPMC eme ihe n'ọtụtụ ebe n'ọgwụ, ihe owuwu ụlọ, ihe mkpuchi, nri, ihe ịchọ mma, wdg, ọkachasị n'ihe ndị chọrọ ka ihe dị arọ, mwepụta a na-achịkwa, nhazi ihe nkiri, nkwụsịtụ, emulsification na ọrụ ndị ọzọ.