Hydroxypropyl methylcellulose (HPMC) jẹ ẹya pataki ologbele-synthetic cellulose ether yellow, eyiti o jẹ lilo pupọ ni oogun, awọn ohun elo ile, ounjẹ, awọn aṣọ ati awọn ile-iṣẹ miiran. HPMC ni o nipọn ti o dara, emulsification, film-forming, moisturizing, imuduro ati awọn ohun-ini miiran, nitorina o ni iye ohun elo pataki ni ọpọlọpọ awọn aaye. Awọn ohun elo aise akọkọ fun iṣelọpọ HPMC pẹlu cellulose, sodium hydroxide, propylene oxide, methyl kiloraidi ati omi.
1. Cellulose
Cellulose jẹ ohun elo aise akọkọ ti HPMC, nigbagbogbo yo lati awọn okun ọgbin adayeba gẹgẹbi owu ati igi. Cellulose jẹ polima Organic adayeba lọpọlọpọ julọ lori ilẹ. Ẹya molikula rẹ jẹ polysaccharide pq gigun ti o ni awọn ẹyọ glukosi ti o ni asopọ nipasẹ awọn ifunmọ β-1,4-glycosidic. Cellulose funrararẹ ko ṣee ṣe ninu omi ati pe ko ni ifaseyin kemikali to dara. Nitorinaa, lẹsẹsẹ awọn ilana iyipada kemikali ni a nilo lati jẹki solubility rẹ ati iṣẹ ṣiṣe lati mura ọpọlọpọ awọn ọja ether cellulose.
2. Sodium hydroxide (NaOH)
Sodium hydroxide, ti a tun mọ ni omi onisuga caustic, jẹ agbo-ara ipilẹ ti o lagbara ti o ṣe ipa pataki bi alkalizer ninu ilana iṣelọpọ ti HPMC. Ni ipele ibẹrẹ ti iṣelọpọ, cellulose ṣe atunṣe pẹlu ojutu iṣuu soda hydroxide lati mu awọn ẹgbẹ hydroxyl ṣiṣẹ lori ẹwọn molikula cellulose, nitorinaa pese awọn aaye ifaseyin fun ifaseyin etherification ti o tẹle. Igbesẹ yii ni a tun pe ni "idahun alkalization". cellulose alkalized faragba awọn iyipada igbekalẹ kan, ti o mu ki o rọrun lati fesi pẹlu awọn reagents kẹmika ti o tẹle (gẹgẹbi propylene oxide ati methyl kiloraidi).
3. Propylene oxide (C3H6O)
Propylene oxide jẹ ọkan ninu awọn aṣoju etherifying bọtini ni iṣelọpọ HPMC, ni pataki ti a lo lati ṣe iyipada awọn ẹgbẹ hydroxyl ni cellulose sinu awọn ẹgbẹ hydroxypropyl. Ni pataki, cellulose alkalized ṣe atunṣe pẹlu ohun elo afẹfẹ propylene labẹ iwọn otutu kan ati awọn ipo titẹ, ati awọn ẹgbẹ iposii ti nṣiṣe lọwọ ninu ohun elo afẹfẹ propylene ti sopọ si ẹwọn molikula ti cellulose nipasẹ iṣesi afikun ṣiṣi oruka lati ṣe aropo hydroxypropyl kan. Ilana yi yoo fun HPMC ti o dara omi solubility ati nipon agbara.
4. Methyl kiloraidi (CH3Cl)
Methyl kiloraidi jẹ oluranlowo etherifying pataki miiran ti a lo lati yi awọn ẹgbẹ hydroxyl ti cellulose pada si awọn ẹgbẹ methoxyl. Methyl kiloraidi ṣe atunṣe pẹlu awọn ẹgbẹ hydroxyl lori ẹwọn molikula cellulose nipasẹ iṣe aropo nucleophilic lati ṣe agbejade cellulose methyl. Nipasẹ iṣesi methylation yii, HPMC gba hydrophobicity ti o dara, ni pataki ti n ṣafihan solubility ti o dara julọ ni diẹ ninu awọn olomi Organic. Ni afikun, ifihan ti awọn ẹgbẹ methoxy siwaju si ilọsiwaju ohun-ini iṣelọpọ fiimu ati iduroṣinṣin kemikali ti HPMC.
5. Omi
Omi, bi ohun olomi ati ifaseyin alabọde, nṣiṣẹ nipasẹ gbogbo HPMC gbóògì ilana. Ninu alkalization ati awọn aati etherification, omi kii ṣe iranlọwọ nikan lati tu iṣuu soda hydroxide ati ṣatunṣe ipo hydration ti cellulose, ṣugbọn tun ṣe alabapin ninu ilana ti ooru ifa lati rii daju iṣakoso iwọn otutu jakejado ilana iṣe. Iwa mimọ ti omi ni ipa pataki lori didara HPMC, ati omi ti a ti sọ di mimọ ti o ga julọ tabi omi distilled nigbagbogbo nilo.
6. Organic epo
Ninu ilana iṣelọpọ ti HPMC, diẹ ninu awọn igbesẹ ilana le tun nilo lilo diẹ ninu awọn olomi Organic, gẹgẹbi kẹmika tabi ethanol. Awọn olomi wọnyi ni a lo nigba miiran lati ṣatunṣe iki ti eto ifaseyin, dinku iṣelọpọ ti awọn ọja-ọja, tabi ṣe igbega awọn aati kemikali kan pato. Yiyan olomi Organic nilo lati pinnu ni ibamu si awọn iwulo ti ilana iṣelọpọ ati ohun elo ti ọja ikẹhin.
7. Awọn ohun elo iranlọwọ miiran
Ni afikun si awọn ohun elo aise akọkọ ti o wa loke, ninu ilana iṣelọpọ gangan, diẹ ninu awọn ohun elo iranlọwọ ati awọn afikun, gẹgẹbi awọn ayase, awọn amuduro, ati bẹbẹ lọ, le ṣee lo lati mu imudara iṣesi ṣiṣẹ, ṣakoso oṣuwọn ifaseyin tabi ilọsiwaju awọn ohun-ini ti ara ati kemikali ti ik ọja.
8. Awọn igbesẹ akọkọ ti ilana iṣelọpọ
Awọn igbesẹ ilana akọkọ fun iṣelọpọ HPMC le pin si awọn ẹya mẹta: alkalization, etherification ati itọju yomi. Ni akọkọ, cellulose ṣe atunṣe pẹlu iṣuu soda hydroxide si alkalize lati dagba cellulose alkali. Lẹhinna, etherification waye ninu iṣesi ti cellulose alkali pẹlu propylene oxide ati methyl kiloraidi lati dagba hydroxypropyl ati methoxy rọpo cellulose ethers. Lakotan, nipasẹ itọju didoju, fifọ, gbigbe ati awọn ilana miiran, awọn ọja HPMC pẹlu solubility pato, iki ati awọn abuda miiran ni a gba.
9. Ipa ti didara ohun elo aise lori iṣẹ ti awọn ọja HPMC
Awọn orisun ohun elo aise oriṣiriṣi ati mimọ ni ipa pataki lori didara ati iṣẹ ti HPMC ikẹhin. Fun apẹẹrẹ, mimọ ati pinpin iwuwo molikula ti awọn ohun elo aise cellulose yoo ni ipa lori iki ati solubility ti HPMC; iwọn lilo ati awọn ipo iṣe ti propylene oxide ati methyl kiloraidi yoo pinnu iwọn ti hydroxypropyl ati aropo methoxy, nitorinaa ni ipa ipa ti o nipọn ati awọn ohun-ini iṣelọpọ fiimu ti ọja naa. Nitorinaa, yiyan ati iṣakoso didara ti awọn ohun elo aise jẹ pataki lakoko ilana iṣelọpọ.
Awọn ohun elo aise akọkọ ti hydroxypropyl methylcellulose (HPMC) pẹlu cellulose, sodium hydroxide, propylene oxide, methyl kiloraidi ati omi. Nipasẹ lẹsẹsẹ awọn aati kemikali eka, awọn ohun elo aise wọnyi ti yipada si ohun elo iṣẹ kan pẹlu iye ohun elo jakejado. Iwọn ohun elo ti HPMC ni wiwa ọpọlọpọ awọn aaye bii oogun, awọn ohun elo ile, ati ounjẹ. Awọn ohun-ini ti ara ti o dara ati kemikali jẹ ki o ṣe pataki ni ọpọlọpọ awọn ile-iṣẹ.
Akoko ifiweranṣẹ: Oṣu Kẹsan-30-2024