Ukuhlanganiswa kwe-Hydroxypropyl Methyl Cellulose Acetate ne-Propionate

Ukusebenzisa i-hydroxypropyl methylcellulose (HPMC) njengempahla eluhlaza, i-acetic anhydride ne-propionic anhydride njengama-esterification agents, ukusabela kwe-esterification ku-pyridine kulungiselelwe i-hydroxypropyl methylcellulose acetate kanye ne-hydroxypropyl methylcellulose Cellulose propionate. Ngokushintsha inani le-solvent esetshenziswa ohlelweni, umkhiqizo onezakhiwo ezingcono kanye neziqu zokushintsha watholwa. Idigri yokushintsha yanqunywa indlela yokubhalwa kwetitration, futhi umkhiqizo waphawulwa futhi wahlolelwa ukusebenza. Imiphumela ibonise ukuthi isistimu yokusabela isabele ku-110°C isikhathi esingamahora angu-1-2.5, futhi amanzi enziwe nge-deionized asetshenziswa njenge-ejenti ethela amanzi ngemva kokusabela, futhi imikhiqizo eyimpushana enezinga lokushintsha elingaphezu kuka-1 (izinga lethiyori lokushintshwa lalingu-2) lingatholakala. Inokuncibilika okuhle kuzinyibilikisi ezihlukahlukene eziphilayo njenge-ethyl ester, i-acetone, i-acetone/amanzi, njll.

Amagama angukhiye: i-hydroxypropyl i-methylcellulose; i-hydroxypropyl methylcellulose acetate; i-hydroxypropyl methylcellulose propionate

IHydroxypropylmethylcellulose (HPMC) iyinhlanganisela ye-polymer engeyona i-ionic kanye ne-cellulose ether enezinhlobonhlobo zokusetshenziswa. Njengesengezo samakhemikhali esihle kakhulu, i-HPMC ivame ukusetshenziswa emikhakheni ehlukahlukene futhi ibizwa ngokuthi “industrial monosodium glutamate”. IHydroxypropyl methylcellulose (HPMC) ayigcini nje ngokuba nemisebenzi emihle yokuhlanganisa, ukuqina, nokubopha, kodwa futhi ingasetshenziswa ukugcina umswakama nokuvikela ama-colloid. Isetshenziswa kabanzi emikhakheni eminingi efana nokudla, imithi, okokugqoka, izindwangu kanye nezolimo. . Ukuguqulwa kwe-hydroxypropyl methylcellulose kungashintsha ezinye zezakhiwo zayo, ukuze isetshenziswe kangcono endaweni ethile. I-molecular formula ye-monomer yayo ithi C10H18O6.

Eminyakeni yamuva nje, ucwaningo lokuphuma kwe-hydroxypropyl methylcellulose seluphenduke indawo eshisayo kancane kancane. Ngokulungisa i-hydroxypropyl methylcellulose, izinhlanganisela ezihlukahlukene zokuphuma kokunye ezinezakhiwo ezihlukene zingatholakala. Isibonelo, ukwethulwa kwamaqembu e-acetyl kungashintsha ukuguquguquka kwamafilimu enamathela ezokwelapha.

Ukuguqulwa kwe-hydroxypropyl methylcellulose kuvame ukwenziwa phambi kwe-acid catalyst efana ne-concentrated sulfuric acid. Ukuhlolwa kuvame ukusebenzisa i-acetic acid njengesinyibilikisi. Izimo zokusabela zinzima futhi zidla isikhathi, futhi umkhiqizo owumphumela unezinga eliphansi lokushintshwa. (ngaphansi kuka-1).

Kuleli phepha, i-acetic anhydride ne-propionic anhydride zisetshenziswe njengama-esterification agents ukuze kulungiswe i-hydroxypropyl methylcellulose ukuze kulungiswe i-hydroxypropyl methylcellulose acetate ne-hydroxypropyl methylcellulose propionate. Ngokuhlola izimo ezinjengokukhethwa kwe-solvent (pyridine), umthamo we-solvent, njll., kuthenjwa ukuthi umkhiqizo onezakhiwo ezingcono kanye ne-substitution degree ingatholakala ngendlela elula. Kuleli phepha, ngocwaningo lokuhlola, umkhiqizo okuhlosiwe one-powdery precipitate kanye ne-degree of substitution enkulu kune-1 yatholwa, enikeze isiqondiso esithile sethiyori sokukhiqizwa kwe-hydroxypropyl methylcellulose acetate kanye ne-hydroxypropyl methylcellulose propionate.

1. Ingxenye yokuhlola

1.1 Izinto zokwakha kanye nama-reagents

Ibanga lemithi ye-hydroxypropyl methylcellulose (KIMA CHEMICAL CO.,LTD, 60HD100, ingxenyenamba ye-methoxyl mass 28% -30%, ingxenyenamba ye-hydroxypropoxyl mass 7% -12%); acetic anhydride, AR, Sinopharm Group Chemical Reagent Co., Ltd.; I-Propionic Anhydride, i-AR, i-West Asia Reagent; I-Pyridine, AR, i-Tianjin Kemiou Chemical Reagent Co., Ltd.; I-methanol, i-ethanol, i-ether, i-ethyl acetate, i-acetone, i-NaOH ne-HCl ayatholakala ngokudayiswa ngokuhlaziya okumsulwa.

Ingubo yokushisa kagesi ye-KDM thermostat, isivinini se-JJ-1A esikala isibonisi sikagesi sedijithali, i-NEXUS 670 Fourier iguqule i-infrared spectrometer.

1.2 Ukulungiswa kwe-hydroxypropyl methylcellulose acetate

Inani elithile le-pyridine lanezelwa ku-flask enentamo emithathu, kwase kwengezwa u-2.5 g we-hydroxypropyl methylcellulose lapho, ama-reactants anyakaziswa ngokulinganayo, futhi izinga lokushisa lakhushulwa lafika ku-110.°C. Engeza u-4 mL we-acetic anhydride, sabela ku-110°C ngehora elingu-1, misa ukufudumeza, uphole ekamelweni lokushisa, engeza amanzi amaningi akhishwe ukuze uphuze umkhiqizo, hlunga ngokumunca, geza ngamanzi angcolile izikhathi eziningana kuze kube yilapho i-eluate ingathathi hlangothi, bese womisa umkhiqizo.

1.3 Ukulungiswa kwe-hydroxypropyl methylcellulose propionate

Inani elithile le-pyridine lengezwe kuflask enezintamo ezintathu, kwase kwengezwa u-0.5 g we-hydroxypropyl methylcellulose lapho, ama-reactants anyakaziswa ngokulinganayo, futhi izinga lokushisa lakhushulelwa ku-110.°C. Engeza u-1.1 mL we-propionic anhydride, sabela kokungu-110°C amahora angu-2.5, misa ukufudumeza, upholile ekamelweni lokushisa, engeza amanzi amaningi akhishwe ukuze uphuze umkhiqizo, hlunga ngokumunca, ugeze ngamanzi akhishwe izikhathi eziningana kuze kube yilapho i-eluate iyimpahla ephakathi, gcina umkhiqizo womile.

1.4 Ukunqunywa kwe-infrared spectroscopy

I-hydroxypropyl methylcellulose, i-hydroxypropyl methylcellulose acetate, i-hydroxypropyl methylcellulose propionate ne-KBr zaxutshwa futhi zagaywa ngokulandelana, zase zicindezelwa kumaphilisi ukuze kutholwe i-spectrum ye-infrared.

1.5 Ukunqunywa kwezinga lokushintshwa

Lungiselela izixazululo ze-NaOH ne-HCl nge-concentration ye-0.5 mol/L, futhi wenze ukulinganisa ukuze unqume ukugxila okuqondile; kala u-0.5 g we-hydroxypropylmethylcellulose acetate (hydroxypropylmethylcellulose propionic acid ester) eflaskni ye-Erlenmeyer engu-250 mL, engeza u-25 mL we-acetone namaconsi ama-3 esikhombi se-phenolphthalein, hlanganisa kahle, bese ufaka u-25 mL we-NaOH uzibuthe ukuze uxube i-electromagnetic solution, 2 ihora; i-titrate nge-HCI kuze kube yilapho umbala obomvu wesisombululo uphela, bhala Ivolumu V1 (V2) ye-hydrochloric acid esetshenzisiwe; sebenzisa indlela efanayo ukuze ulinganise umthamo we-V0 we-hydrochloric acid esetshenziswe i-hydroxypropyl methylcellulose, futhi ubale izinga lokushintshwa.

1.6 Ukuhlolwa kokuncibilika

Thatha inani elifanele lemikhiqizo yokwenziwa, uyifake ku-solvent ye-organic, unyakazise kancane, bese ubheka ukuchithwa kwento.

2. Imiphumela Nezingxoxo

2.1 Umphumela yenani le-pyridine (i-solvent)

Imiphumela yamanani ahlukene e-pyridine ku-morphology ye-hydroxypropylmethylcellulose acetate kanye ne-hydroxypropylmethylcellulose propionate. Uma inani le-solvent lincane, lizonciphisa ukwanda kweketango le-macromolecular kanye ne-viscosity yesistimu, ukuze izinga le-esterification yesistimu yokusabela lincishiswe, futhi umkhiqizo uzokwenyuka njengenqwaba enkulu. Futhi uma inani le-solvent liphansi kakhulu, i-reactant kulula ukuyihlanganisa ibe yiqhubu futhi inamathele odongeni lwesitsha, okungeyona nje into engalungile ekwenzeni ukusabela, kodwa futhi kubangela ukuphazamiseka okukhulu ekwelapheni ngemva kokusabela. . Ekuhlanganisweni kwe-hydroxypropyl methylcellulose acetate, inani le-solvent esetshenzisiwe lingakhethwa njenge-150 mL / 2 g; ukuze kuhlanganiswe i-hydroxypropyl methylcellulose propionate, ingakhethwa njengo-80 mL/0.5 g.

2.2 Ukuhlaziya i-infrared spectrum

Ishadi lokuqhathanisa le-infrared le-hydroxypropyl methylcellulose ne-hydroxypropyl methylcellulose acetate. Uma kuqhathaniswa nezinto ezingavuthiwe, i-spectrogram ye-infrared yomkhiqizo we-hydroxypropyl methylcellulose acetate inoshintsho olusobala kakhudlwana. Ku-spectrum ye-infrared yomkhiqizo, ukuphakama okuqinile kwavela ku-1740cm-1, okubonisa ukuthi iqembu le-carbonyl lakhiqizwa; ngaphezu kwalokho, ukuqina kokuphakama kokudlidliza okunwebekayo kwe-OH ku-3500cm-1 kwakuphansi kakhulu kunaleyo yezinto ezingavuthiwe, okuphinde kwabonisa ukuthi -OH Kwakukhona ukusabela.

I-spectrogram ye-infrared yomkhiqizo we-hydroxypropyl methylcellulose propionate nayo ishintshe kakhulu uma iqhathaniswa nempahla eluhlaza. Ku-spectrum ye-infrared yomkhiqizo, ukuphakama okuqinile kwavela ku-1740 cm-1, okubonisa ukuthi iqembu le-carbonyl lakhiqizwa; ngaphezu kwalokho, i-OH enwebekayo yokuqina kokudlidliza ku-3500 cm-1 yayiphansi kakhulu kunaleyo yezinto ezingavuthiwe, okuphinde kwabonisa ukuthi i-OH isabele.

2.3 Ukunqunywa kwezinga lokushintshwa

2.3.1 Ukunqunywa kwedigri yokushintsha ye-hydroxypropyl methylcellulose acetate

Njengoba i-hydroxypropyl methylcellulose ine-OH eyodwa eyodwa kuyunithi ngayinye, futhi i-cellulose acetate iwumkhiqizo otholwe ngokufaka i-COCH3 eyodwa ku-H ku-OH eyodwa, idigri enkulu yokufaka esikhundleni (Ds) ngu-2.

2.3.2 Ukunqunywa kwezinga lokushintshwa kwe-hydroxypropyl methylcellulose propionate

2.4 Ukuncibilika komkhiqizo

Izinto ezimbili ezihlanganisiwe zazinezici ezifanayo zokuncibilika, futhi i-hydroxypropyl methylcellulose acetate yayincibilika kancane kune-hydroxypropyl methylcellulose propionate. Umkhiqizo wokwenziwa ungancibilika ku-acetone, i-ethyl acetate, i-acetone/i-solvent exutshwe namanzi, futhi unokukhetha okwengeziwe. Ukwengeza, umswakama oqukethwe ku-acetone/i-solvent exutshwe namanzi ungenza okuphuma ku-cellulose kuphephe kakhulu futhi kungabi nemvelo uma kusetshenziswa njengezinto zokumboza.

3. Isiphetho

(1) Izimo zokwenziwa kwe-hydroxypropyl methylcellulose acetate zimi kanje: 2.5 g ye-hydroxypropyl methylcellulose, i-acetic anhydride njenge-esterification agent, 150 mL ye-pyridine njengesinyibiliki, izinga lokushisa lokusabela ku-110° C, kanye nesikhathi sokuphendula 1 h.

(2) Izimo zokwenziwa kwe-hydroxypropyl methylcellulose acetate yilezi: 0.5 g we-hydroxypropyl methylcellulose, i-propionic anhydride njenge-esterification agent, 80 mL ye-pyridine njengesinyibiliki, izinga lokushisa lokusabela ku-110°C, nesikhathi sokuphendula singamahora angu-2.5.

(3) Izinto eziphuma ku-cellulose ezihlanganiswe ngaphansi kwalesi simo zisesimweni ngokuqondile sezimpushana ezinhle ezinezinga elihle lokushintshwa, futhi lezi zinto ezimbili eziphuma ku-cellulose zingancibilika kuzincibilikisi ezihlukahlukene zezinto eziphilayo njenge-ethyl acetate, i-acetone, ne-acetone/amanzi.