IHydroxypropyl methylcellulose (HPMC) yipolymer eguquguqukayo eneendlela ezahlukeneyo zokusetyenziswa kumashishini ahlukeneyo kuquka amayeza, ukutya, ulwakhiwo kunye nezinto zokuthambisa. Izinto eziphambili ezisetyenziswayo ukwenza i-HPMC yi-cellulose kunye ne-propylene oxide.
1. I-Cellulose: isiseko se-HPMC
1.1 Isishwankathelo se-cellulose
I-Cellulose yi-carbohydrate eyinkimbinkimbi eyiyeyona nto iphambili kwisakhiwo seendonga zeeseli zezityalo eziluhlaza. Iqulethwe ziintambo ezithe ngqo zeemolekyuli zeglucose ezidityaniswe kunye ziibhondi ze-β-1,4-glycosidic. Ubuninzi bamaqela e-hydroxyl kwi-cellulose buyenza ibe yinto efanelekileyo yokuqala yokwenza izinto ezahlukeneyo ze-cellulose, kuquka ne-HPMC.
1.2 Ukuthengwa kweseli
I-Cellulose inokufumaneka kwizinto ezahlukeneyo zezityalo, ezifana ne-pulp yomthi, ii-cotton linters, okanye ezinye izityalo ezine-fibrous. I-pulp yomthi ngumthombo oqhelekileyo ngenxa yobuninzi bayo, ukusebenza kakuhle kweendleko, kunye nozinzo. Ukukhupha i-cellulose kudla ngokubandakanya ukuqhekeza imicu yezityalo ngothotho lweenkqubo ze-mechanical kunye neekhemikhali.
1.3 Ubunyulu kunye neempawu
Umgangatho kunye nobunyulu be-cellulose zibalulekile ekumiseleni iimpawu zemveliso yokugqibela ye-HPMC. I-cellulose ecocekileyo kakhulu iqinisekisa ukuba i-HPMC iveliswa ngeempawu ezifanayo ezifana ne-viscosity, ukunyibilika kunye nozinzo lobushushu.
2. I-propylene oxide: ukungeniswa kweqela le-hydroxypropyl
2.1 Intshayelelo kwi-propylene oxide
I-Propylene oxide (PO) yikhompawundi yendalo enefomyula yekhemikhali i-C3H6O. Yi-epoxide, oko kuthetha ukuba ine-athomu yeoksijini edityaniswe nee-athomu ezimbini zekhabhoni ezikufutshane. I-Propylene oxide yeyona nto ibalulekileyo ekuvelisweni kwe-hydroxypropyl cellulose, eyinxalenye ephakathi yokuveliswa kwe-HPMC.
2.2 Inkqubo ye-Hydroxypropylation
Inkqubo ye-hydroxypropylation ibandakanya ukusabela kwe-cellulose kunye ne-propylene oxide ukungenisa amaqela e-hydroxypropyl kwi-cellulose backbone. Olu kusabela ludla ngokwenziwa xa kukho i-catalyst esisiseko. Amaqela e-hydroxypropyl anika ukunyibilika okuphuculweyo kunye nezinye iimpawu ezinqwenelekayo kwi-cellulose, nto leyo ekhokelela ekwakhiweni kwe-hydroxypropyl cellulose.
3. I-Methylation: Ukongeza amaqela e-methyl
3.1 Inkqubo yeMethylation
Emva kwe-hydroxypropylation, inyathelo elilandelayo ekuqulunqweni kwe-HPMC yi-methylation. Le nkqubo ibandakanya ukungeniswa kwamaqela e-methyl kumqolo we-cellulose. I-Methyl chloride sisixhobo esisetyenziswa kakhulu kule mpendulo. Ubungakanani be-methylation buchaphazela iipropati zemveliso yokugqibela ye-HPMC, kubandakanya i-viscosity yayo kunye nokuziphatha kwejeli.
3.2 Umgangatho wokutshintsha
Iqondo lokutshintshwa (DS) liyiparameter ebalulekileyo yokulinganisa inani eliphakathi lezinto ezithatha indawo (i-methyl kunye ne-hydroxypropyl) ngeyunithi nganye ye-anhydroglucose kwikhonkco le-cellulose. Inkqubo yokuvelisa ilawulwa ngononophelo ukuze kufezekiswe ukusebenza okunqwenelekayo kweemveliso ze-HPMC.
4. Ukucoca kunye noLawulo loMgangatho
4.1 Ukususwa kweemveliso ezingaphantsi kwemveliso
Ukwenziwa kwe-HPMC kunokubangela ukwenziwa kweemveliso ezingaphantsi kwe-HPMC ezifana neetyuwa okanye ii-reagents ezingaphendulwanga. Amanyathelo okucoca aquka ukuhlamba kunye nokucoca asetyenziselwa ukususa ezi zinto zingcolileyo kunye nokunyusa ubumsulwa bemveliso yokugqibela.
4.2 Amanyathelo okulawula umgangatho
Amanyathelo okulawula umgangatho angqongqo ayasetyenziswa kuyo yonke inkqubo yokuvelisa ukuqinisekisa ukuhambelana kunye nomgangatho we-HPMC. Iindlela zokuhlalutya ezifana ne-spectroscopy, i-chromatography kunye ne-rheology zisetyenziselwa ukuvavanya iiparameter ezifana nobunzima be-molecular, i-degree of substitution kunye ne-viscosity.
5. Iimpawu zeHydroxypropyl Methylcellulose (HPMC)
5.1 Iimpawu ezibonakalayo
I-HPMC yimpuphu emhlophe ukuya kwemhlophe, engenavumba kwaye ineempawu ezintle zokwenza ifilimu. I-hygroscopic kwaye yenza ijeli ecacileyo ngokulula xa isasazwa emanzini. Ukunyibilika kwe-HPMC kuxhomekeke kwinqanaba lokutshintshwa kwaye kuchatshazelwa zizinto ezifana nobushushu kunye ne-pH.
5.2 Ulwakhiwo lweekhemikhali
Ulwakhiwo lweekhemikhali lwe-HPMC luqulathe umqolo we-cellulose one-hydroxypropyl kunye ne-methyl substituents. Umlinganiselo wezi substituents, obonakaliswa kwinqanaba lokutshintshwa, umisela ulwakhiwo lweekhemikhali luphela kwaye ngaloo ndlela iimpawu ze-HPMC.
5.3 Iimpawu zokuxinana kunye neempawu ze-rheological
I-HPMC ifumaneka kwiindidi ezahlukeneyo ezinobubanzi obahlukeneyo be-viscosity. I-viscosity yezisombululo ze-HPMC yinto ebalulekileyo kwizicelo ezifana namayeza, apho ichaphazela iprofayili yokukhululwa kwesiyobisi, nakwisakhiwo, apho ichaphazela ukusebenza kakuhle kweemortar kunye neepaste.
5.4 Iimpawu zokwenza ifilimu kunye nokwenza iqine
I-HPMC isetyenziswa kakhulu njengefilimu esetyenziswa kwiingubo zamayeza kwaye njengearhente yokutyeba kwiindlela ezahlukeneyo zokwenziwa kwefilimu. Amandla ayo okwenza ifilimu ayenza ibe luncedo ekuphuhlisweni kweenkqubo zokutyeba zamayeza ezikhutshwayo ezilawulwayo, ngelixa iimpawu zayo zokutyeba ziphucula ubume kunye nozinzo lweemveliso ezininzi.
6. Ukusetyenziswa kwe-hydroxypropyl methylcellulose
6.1 Ishishini leMithi
Kwishishini lezemithi, i-HPMC isetyenziselwa ukwenza iifom zedosi eqinileyo yomlomo ezifana neepilisi kunye neekhaphu. Isetyenziswa kakhulu njenge-binder, disintegrant kunye ne-film coating agent. Iipropati zokukhululwa ezilawulwayo ze-HPMC zenza kube lula ukusetyenziswa kwayo kwiifomyula ezikhutshwayo rhoqo.
6.2 Ishishini lokwakha
Kwicandelo lokwakha, i-HPMC isetyenziswa njengesixhobo sokugcina amanzi, isithambisi kunye nesincamathelisi kwiimveliso ezisekwe kwisamente. Iphucula ukusebenza kakuhle kwesamente, ithintela ukugoba xa isetyenziswa ngokuthe nkqo, kwaye iphucula ukusebenza ngokubanzi kwezixhobo zokwakha.
6.3 Ishishini lokutya
I-HPMC isetyenziswa kwishishini lokutya njengesithambisi, isiqinisi kunye nesixubisisi. Amandla ayo okwenza iijeli ngomlinganiselo ophantsi ayenza ifaneleke kwiintlobo ngeentlobo zezicelo, kubandakanya iisosi, iidizethi kunye needizethi.
6.4 Izinto zokuthambisa kunye neemveliso zokhathalelo lomntu
Kwizinto zokuthambisa kunye neemveliso zokhathalelo lomntu, i-HPMC ifumaneka kwiindidi ezahlukeneyo zeemveliso kuquka iikhrimu, iiloshini kunye neeshampu. Inceda ukuphucula ubume, uzinzo kunye nokusebenza ngokubanzi kwezi mveliso.
6.5 Amanye amashishini
Ukuguquguquka kwe-HPMC kufikelela nakwamanye amashishini, kuquka amalaphu, iipeyinti kunye nezinto zokuncamathelisa, apho ingasetyenziswa njengesixhobo sokuguqula i-rheology, iarhente yokugcina amanzi kunye nesixhobo sokwandisa ukuqina.
7. Isiphelo
I-Hydroxypropylmethylcellulose yi-polymer eguquguqukayo enezicelo ezininzi. Ukwenziwa kwayo kusebenzisa i-cellulose kunye ne-propylene oxide njengezinto eziphambili zokwenziwa, kwaye i-cellulose iguqulwa ngeenkqubo ze-hydroxypropylation kunye ne-methylation. Ulawulo olulawulwayo lwezi zinto zokwenziwa kunye neemeko zokusabela lunokuvelisa i-HPMC eneempawu ezenzelwe wena ukuhlangabezana neemfuno ezithile zoshishino. Ke ngoko, i-HPMC idlala indima ebalulekileyo ekuphuculeni ukusebenza kunye nokusebenza kweemveliso kumashishini onke. Ukuhlolwa okuqhubekayo kwezicelo ezintsha kunye nokuphuculwa kweenkqubo zokwenziwa kunceda i-HPMC iqhubeke nokudlala indima ebalulekileyo kwimarike yehlabathi.
Ixesha lokuthumela: Disemba-28-2023