Akopọ ti Hydroxypropyl Methyl Cellulose Acetate ati Propionate

Lilo hydroxypropyl methylcellulose (HPMC) bi awọn ohun elo aise, acetic anhydride ati propionic anhydride gẹgẹbi awọn aṣoju esterification, iṣesi esterification ni pyridine pese hydroxypropyl methylcellulose acetate ati hydroxypropyl methylcellulose Cellulose propionate. Nipa yiyipada iye epo ti a lo ninu eto naa, ọja kan pẹlu awọn ohun-ini to dara julọ ati alefa aropo ti gba. Iwọn aropo jẹ ipinnu nipasẹ ọna titration, ati pe ọja naa jẹ afihan ati idanwo fun iṣẹ ṣiṣe. Awọn abajade fihan pe eto ifaseyin ti ṣe ni 110°C fun awọn wakati 1-2.5, ati omi ti a ti sọ diionized ni a lo bi oluranlowo itunnu lẹhin ifura, ati pe awọn ọja powdery pẹlu iwọn aropo ti o tobi ju 1 (iwọn arosọ ti aropo jẹ 2) le gba. O ni solubility ti o dara ni ọpọlọpọ awọn olomi Organic gẹgẹbi ethyl ester, acetone, acetone / omi, ati bẹbẹ lọ.

Awọn ọrọ pataki: hydroxypropyl methylcellulose; hydroxypropyl methylcellulose acetate; hydroxypropyl methylcellulose propionate

Hydroxypropylmethylcellulose (HPMC) jẹ apopọ polima ti kii ṣe ionic ati ether cellulose kan pẹlu ọpọlọpọ awọn lilo. Gẹgẹbi afikun kemikali ti o dara julọ, HPMC ni igbagbogbo lo ni awọn aaye pupọ ati pe a pe ni “monosodium glutamate ile-iṣẹ”. Hydroxypropyl methylcellulose (HPMC) kii ṣe nikan ni awọn emulsifying ti o dara, nipọn, ati awọn iṣẹ abuda, ṣugbọn tun le ṣee lo lati ṣetọju ọrinrin ati daabobo awọn colloid. O ti wa ni lilo pupọ ni ọpọlọpọ awọn aaye bii ounjẹ, oogun, awọn aṣọ, awọn aṣọ, ati iṣẹ-ogbin. . Iyipada ti hydroxypropyl methylcellulose le yi diẹ ninu awọn ohun-ini rẹ pada, ki o le ṣee lo daradara ni aaye kan. Ilana molikula ti monomer rẹ jẹ C10H18O6.

Ni awọn ọdun aipẹ, iwadii lori awọn itọsẹ hydroxypropyl methylcellulose ti di aaye gbigbona diẹdiẹ. Nipa iyipada hydroxypropyl methylcellulose, ọpọlọpọ awọn agbo ogun itọsẹ pẹlu awọn ohun-ini oriṣiriṣi le ṣee gba. Fun apẹẹrẹ, ifihan ti awọn ẹgbẹ acetyl le yi iyipada ti awọn fiimu ti a bo iṣoogun pada.

Iyipada ti hydroxypropyl methylcellulose ni a maa n ṣe ni iwaju ayase acid gẹgẹbi imi-ọjọ sulfuric ogidi. Idanwo naa nigbagbogbo nlo acetic acid bi epo. Awọn ipo ifaseyin jẹ cumbersome ati akoko n gba, ati pe ọja ti o yọrisi ni iwọn kekere ti aropo. (kere ju 1).

Ninu iwe yii, acetic anhydride ati propionic anhydride ni a lo bi awọn aṣoju esterification lati yipada hydroxypropyl methylcellulose lati mura hydroxypropyl methylcellulose acetate ati hydroxypropyl methylcellulose propionate. Nipa wiwa awọn ipo bii yiyan epo (pyridine), iwọn lilo epo, ati bẹbẹ lọ, a nireti pe ọja kan pẹlu awọn ohun-ini to dara julọ ati alefa aropo le ṣee gba nipasẹ ọna ti o rọrun. Ninu iwe yii, nipasẹ iwadii esiperimenta, ọja ibi-afẹde pẹlu precipitate powdery ati iwọn aropo ti o tobi ju 1 ni a gba, eyiti o pese diẹ ninu awọn itọnisọna imọ-jinlẹ fun iṣelọpọ ti hydroxypropyl methylcellulose acetate ati hydroxypropyl methylcellulose propionate.

1. Apakan idanwo

1.1 Awọn ohun elo ati awọn reagents

Elegbogi ite hydroxypropyl methylcellulose (KIMA CHEMICAL CO., LTD, 60HD100, ida methoxyl mass 28%-30%, hydroxypropoxyl mass ida 7%-12%); acetic anhydride, AR, Sinopharm Group Chemical Reagent Co., Ltd .; Propionic Anhydride, AR, Oorun Asia Reagent; Pyridine, AR, Tianjin Kemiou Chemical Reagent Co., Ltd .; methanol, ethanol, ether, ethyl acetate, acetone, NaOH ati HCl wa ni iṣowo ti o wa ni mimọ ni itupalẹ.

KDM thermostat itanna alapapo aṣọ, JJ-1A iyara wiwọn oni àpapọ ina aruwo, NEXUS 670 Fourier yipada infurarẹẹdi spectrometer.

1.2 Igbaradi ti hydroxypropyl methylcellulose acetate

Iwọn kan ti pyridine ni a fi kun sinu ọpọn ọrùn mẹta, lẹhinna 2.5 g ti hydroxypropyl methylcellulose ti wa ni afikun sibẹ, awọn oludasiṣẹ ti ru ni deede, ati pe iwọn otutu ti ga si 110.°C. Fi 4 milimita ti acetic anhydride kun, fesi ni 110°C fun 1 h, da alapapo duro, dara si iwọn otutu yara, ṣafikun iye nla ti omi deionized lati ṣaju ọja naa, ṣe àlẹmọ pẹlu afamora, wẹ pẹlu omi deionized fun ọpọlọpọ igba titi eluate yoo jẹ didoju, ki o gbẹ fifipamọ ọja naa.

1.3 Igbaradi ti hydroxypropyl methylcellulose propionate

Iwọn kan ti pyridine ni a fi kun sinu ọpọn ọlọrun mẹta, lẹhinna 0.5 g ti hydroxypropyl methylcellulose ti wa ni afikun sibẹ, awọn oludasiṣẹ ti ru ni deede, ati pe iwọn otutu ti ga si 110.°C. Fi 1.1 milimita ti propionic anhydride kun, fesi ni 110°C fun wakati 2.5, dawọ alapapo, tutu si iwọn otutu yara, ṣafikun iye nla ti omi deionized lati ṣaju ọja naa, àlẹmọ pẹlu afamora, wẹ pẹlu omi deionized fun igba pupọ titi ti eluate yoo jẹ ohun-ini alabọde, tọju ọja naa gbẹ.

1.4 Ipinnu ti infurarẹẹdi spectroscopy

Awọn hydroxypropyl methylcellulose, hydroxypropyl methylcellulose acetate, hydroxypropyl methylcellulose propionate ati KBr ni a dapọ ati ilẹ ni atele, ati lẹhinna tẹ sinu awọn tabulẹti lati pinnu iyasọtọ infurarẹẹdi.

1.5 Ipinnu ti ìyí ti aropo

Mura awọn ojutu NaOH ati HCl pẹlu ifọkansi ti 0.5 mol / L, ati ṣe iwọntunwọnsi lati pinnu ifọkansi gangan; ṣe iwọn 0.5 g ti hydroxypropylmethylcellulose acetate (hydroxypropylmethylcellulose propionic acid ester) ninu 250 mL Erlenmeyer flask, fi 25 mL ti acetone ati 3 silė ti phenolphthalein atọka, dapọ daradara, lẹhinna fi 25 mL ti NaOH ojutu, aruwo ati saponre. wakati 2; titrate pẹlu HCI titi awọ pupa ti ojutu yoo parẹ, igbasilẹ Iwọn didun V1 (V2) ti hydrochloric acid ti jẹ; lo ọna kanna lati wiwọn iwọn didun V0 ti hydrochloric acid ti o jẹ nipasẹ hydroxypropyl methylcellulose, ati ṣe iṣiro iwọn aropo.

1.6 Solubility ṣàdánwò

Mu iye ti o yẹ fun awọn ọja sintetiki, ṣafikun wọn si ohun elo Organic, gbọn die-die, ki o ṣe akiyesi itusilẹ nkan naa.

2. Awọn esi ati ijiroro

2.1 Ipa ti iye pyridine (iyọ)

Awọn ipa ti awọn oye oriṣiriṣi ti pyridine lori ẹda ti hydroxypropylmethylcellulose acetate ati hydroxypropylmethylcellulose propionate. Nigbati iye epo ba kere si, yoo dinku extensibility ti pq macromolecular ati iki ti eto naa, nitorinaa iwọn ti esterification ti eto ifaseyin yoo dinku, ati pe ọja naa yoo ṣaju bi ibi-nla kan. Ati pe nigbati iye epo ba lọ silẹ pupọ, oludasiṣẹ jẹ rọrun lati di sinu odidi kan ki o faramọ ogiri eiyan, eyiti kii ṣe aibalẹ nikan fun gbigbe jade ti iṣe, ṣugbọn tun fa aibalẹ nla si itọju lẹhin ifura naa. . Ninu iṣelọpọ ti hydroxypropyl methylcellulose acetate, iye epo ti a lo ni a le yan bi 150 mL / 2 g; fun iṣelọpọ ti hydroxypropyl methylcellulose propionate, o le yan bi 80 mL/0.5 g.

2.2 Infurarẹẹdi spekitiriumu

Aworan afiwe infurarẹẹdi ti hydroxypropyl methylcellulose ati hydroxypropyl methylcellulose acetate. Ti a ṣe afiwe pẹlu ohun elo aise, spectrogram infurarẹẹdi ti ọja hydroxypropyl methylcellulose acetate ni iyipada ti o han gedegbe. Ni irisi infurarẹẹdi ti ọja naa, oke ti o lagbara han ni 1740cm-1, ti o nfihan pe a ṣe agbekalẹ ẹgbẹ carbonyl; ni afikun, awọn kikankikan ti awọn nínàá tente gbigbọn ti OH ni 3500cm-1 wà Elo kekere ju ti awọn aise ohun elo, eyi ti o tun tọkasi wipe -OH Nibẹ je kan lenu.

spectrogram infurarẹẹdi ti ọja hydroxypropyl methylcellulose propionate ti tun yipada ni pataki ni akawe pẹlu ohun elo aise. Ni irisi infurarẹẹdi ti ọja naa, oke ti o lagbara han ni 1740 cm-1, ti o fihan pe a ṣe agbekalẹ ẹgbẹ carbonyl; ni afikun, awọn OH nínàá tente giga kikankikan ni 3500 cm-1 wà Elo kekere ju ti awọn aise ohun elo, eyi ti o tun tọkasi wipe a OH fesi.

2.3 Ipinnu ti ìyí ti aropo

2.3.1 Ipinnu iwọn aropo ti hydroxypropyl methylcellulose acetate

Niwọn igba ti hydroxypropyl methylcellulose ni OH meji kan ni ẹyọ kọọkan, ati acetate cellulose jẹ ọja ti a gba nipasẹ fifidipo COCH3 kan fun H ni OH kan, iwọn aropin ti o pọju ti aropo (Ds) jẹ 2.

2.3.2 Ipinnu iwọn aropo ti hydroxypropyl methylcellulose propionate

2.4 Solubility ti ọja naa

Awọn nkan meji ti a ṣajọpọ ni iru awọn abuda solubility, ati hydroxypropyl methylcellulose acetate jẹ diẹ tiotuka diẹ sii ju hydroxypropyl methylcellulose propionate. Ọja sintetiki le ni tituka ni acetone, ethyl acetate, acetone/omi adalu epo, ati pe o ni yiyan diẹ sii. Ni afikun, ọrinrin ti o wa ninu acetone / omi ti o dapọ epo le jẹ ki awọn itọsẹ cellulose diẹ sii ni ailewu ati ore ayika nigba lilo bi awọn ohun elo ti a bo.

3. Ipari

(1) Awọn ipo iṣelọpọ ti hydroxypropyl methylcellulose acetate jẹ bi atẹle: 2.5 g ti hydroxypropyl methylcellulose, acetic anhydride bi oluranlowo esterification, 150 milimita ti pyridine bi epo, iwọn otutu ifasẹ ni 110° C, ati akoko idahun 1 wakati.

(2) Awọn ipo iṣọpọ ti hydroxypropyl methylcellulose acetate jẹ: 0.5 g ti hydroxypropyl methylcellulose, propionic anhydride bi oluranlowo esterification, 80 milimita ti pyridine bi epo, iwọn otutu lenu ni 110°C, ati akoko idahun ti awọn wakati 2.5.

(3) Awọn itọsẹ cellulose ti a ṣepọ labẹ ipo yii wa ni taara ni irisi awọn erupẹ ti o dara pẹlu iwọn ti o dara ti iyipada, ati awọn itọsẹ cellulose meji wọnyi le ti wa ni tituka ni orisirisi awọn nkan ti ara ẹni gẹgẹbi ethyl acetate, acetone, ati acetone / omi.