Te whakahiato o te Hydroxypropyl Methyl Cellulose Acetate me te Propionate

Ma te whakamahi i te hydroxypropyl methylcellulose (HPMC) hei rauemi mata, te anhydride acetic me te anhydride propionic hei kaihoko esterification, te tauhohenga esterification i roto i te pyridine kua rite te hydroxypropyl methylcellulose acetate me te hydroxypropyl methylcellulose Cellulose propionate. Ma te whakarereke i te nui o te whakarewa i whakamahia i roto i te punaha, i whiwhihia he hua pai ake nga ahuatanga me te tohu whakakapinga. Ko te tohu whakakapinga i whakatauhia e te tikanga titration, ka tohuhia te hua me te whakamatautau mo te mahi. Ko nga hua i whakaatu ko te punaha tauhohenga i tauhohe i te 110°Ko te C mo te 1-2.5 haora, ka whakamahia te wai whakaheke i te wai i muri i te tauhohenga, ka taea te whiwhi i nga hua paura me te tohu whakakapinga nui ake i te 1 (ko te tohu kaupapa whakakapi ko te 2). He pai te whakarewatanga i roto i nga momo whakarewa pararopi penei i te ethyl ester, acetone, acetone/wai, aha atu.

kupu matua: hydroxypropyl methylcellulose; hydroxypropyl methylcellulose acetate; hydroxypropyl methylcellulose propionate

Ko te Hydroxypropylmethylcellulose (HPMC) he pūhui polymer kore-ionic me te cellulose ether me te whānuitanga o nga whakamahinga. Hei taapiri matū tino pai, he maha nga wa e whakamahia ana te HPMC ki nga waahi rereke ka kiia ko "monosodium glutamate ahumahi". Ko te Hydroxypropyl methylcellulose (HPMC) ehara i te mea he pai noa nga mahi whakaemulsifying, thickening, me te here, engari ka taea hoki te whakamahi ki te pupuri i te makuku me te tiaki i nga colloids. Ka whakamahia nuitia i roto i nga mara maha penei i te kai, te rongoa, te paninga, te kakano, me te ahuwhenua. . Ko te whakarereketanga o te hydroxypropyl methylcellulose ka taea te whakarereke i etahi o ona ahuatanga, kia pai ake ai te whakamahi i tetahi mara. Ko te tauira ngota o tana monomer ko C10H18O6.

I nga tau kua pahure ake nei, kua kaha haere te rangahau mo te hydroxypropyl methylcellulose derivatives hei waahi wera. Ma te whakarereke i te hydroxypropyl methylcellulose, ka taea te whiwhi i nga momo momo puhui me nga ahuatanga rereke. Hei tauira, ka taea e te whakaurunga o nga roopu acetyl te whakarereke i te ngawari o nga kiriata paninga rongoa.

Ko te whakarereketanga o te hydroxypropyl methylcellulose i te nuinga o te wa ka mahia i te aroaro o te whakakorikori waikawa penei i te waikawa pungatara kawa. Ko te tikanga ka whakamahia e te whakamatautau te waikawa ahetiki hei whakarewa. Ko nga tikanga tauhohenga he uaua me te wa e kai ana, a ko te hua ka puta he iti rawa te whakakapinga. (iti iho i te 1).

I roto i tenei pepa, i whakamahia te anhydride acetic me te propionic anhydride hei kaihoko whakamaarama hei whakarereke i te hydroxypropyl methylcellulose hei whakarite hydroxypropyl methylcellulose acetate me te hydroxypropyl methylcellulose propionate. Ma te tuhura i nga tikanga penei i te kowhiringa whakarewa (pyridine), inenga whakarewa, me etahi atu, ko te tumanako ka taea te whiwhi i tetahi hua pai ake nga ahuatanga me te tohu whakakapinga ma te huarahi ngawari noa. I roto i tenei pepa, na roto i nga rangahau whakamatautau, i whiwhihia te hua whainga me te parapara paura me te tohu whakakapinga nui ake i te 1, i homai etahi arataki whakaaro mo te hanga o te hydroxypropyl methylcellulose acetate me te hydroxypropyl methylcellulose propionate.

1. Wāhanga whakamātautau

1.1 Rauemi me nga reagents

Ko te tohu rongoa hydroxypropyl methylcellulose (KIMA CHEMICAL CO.,LTD, 60HD100, hautanga papatipu methoxyl 28% -30%, hautanga papatipu hydroxypropoxyl 7% -12%); anhydride acetic, AR, Sinopharm Group Chemical Reagent Co., Ltd.; Propionic Anhydride, AR, West Asia Reagent; Pyridine, AR, Tianjin Kemiou Chemical Reagent Co., Ltd.; Ko te mewaro, te waihano, te etera, te ethyl acetate, te acetone, te NaOH me te HCl kei te waatea ki te hokohoko parakore.

KDM thermostat hiko whakawera koroka, JJ-1A tere ine whakaatu matihiko hiko whakakorikori, NEXUS 670 Fourier te huri i te inenga infrared.

1.2 Te whakarite i te hydroxypropyl methylcellulose acetate

I tapirihia he nui o te pyridine ki roto i te pounamu kaki-toru, katahi ka tapirihia te 2.5 g o te hydroxypropyl methylcellulose ki roto, ka oho riterite nga tauhohenga, ka hiki te mahana ki te 110°C. Taapirihia te 4 mL o te acetic anhydride, tauhohe i te 110°C mo te 1 haora, whakamutua te whakamahana, whakamatao ki te mahana o te rūma, taapirihia he nui o te wai kaoona hei whakaheke i te hua, tātarihia me te momi, horoi ki te wai kaoona mo etahi wa kia noho kore te ruate, ka whakamaroke i te hua whakaora.

1.3 Te whakarite i te hydroxypropyl methylcellulose propionate

I tapirihia he nui o te pyridine ki roto i te ipu kaki-toru, katahi ka tapirihia te 0.5 g o te hydroxypropyl methylcellulose ki roto, ka oho riterite nga tauhohenga, ka hiki te mahana ki te 110°C. Tāpirihia he 1.1 mL o te anhydride propionic, tauhohe i te 110°C mo te 2.5 haora, whakamutua te whakamahana, whakamatao ki te mahana o te rūma, taapirihia he nui o te wai deionized ki te whakaheke i te hua, tātari me te momi, horoi ki te wai deionized mo te maha o nga wa tae noa ki te waahi o te eluate he taonga waenga, rokiroki te hua kia maroke.

1.4 Te Whakataunga o te hihinga infrared

Ko te hydroxypropyl methylcellulose, te hydroxypropyl methylcellulose acetate, te hydroxypropyl methylcellulose propionate me te KBr i konatunatua me te oneone, katahi ka pehia ki roto ki nga papa hei whakatau i te hiranga infrared.

1.5 Te whakatau i te tohu whakakapinga

Whakaritehia nga otinga NaOH me te HCl me te kukū o te 0.5 mol/L, ka whakahaere i te whakatikatika hei whakatau i te kukū tika; paunatia te 0.5 g o te hydroxypropylmethylcellulose acetate (hydroxypropylmethylcellulose propionic acid ester) i roto i te 250 mL Erlenmeyer flask, tāpirihia te 25 mL o te acetone me te 3 pata o te tohu phenolphthalein, uru pai, katahi ka tapirihia te 25 mL o te wairewa NaOHmagnetic whakakorikori me te whakakorikori hiko. 2 h; titrate ki te HCI kia ngaro ra ano te tae whero o te wairewa, tuhia Te rōrahi V1 (V2) o te waikawa pūhaumāota i pau; whakamahia te tikanga ano hei ine i te rōrahi V0 o te waikawa pūmāota i pau e te hydroxypropyl methylcellulose, me te tātai i te tohu whakakapinga.

1.6 Whakamātautau wairewa

Tangohia te nui o nga hua waihanga, whakauruhia ki te whakarewa pararopi, ruru paku, ka titiro ki te memehatanga o te matū.

2. Nga Hua me te Matapaki

2.1 Te painga o te nui o te pyridine (whakarewa)

Nga paanga o te nui o te pyridine ki te ahua o te hydroxypropylmethylcellulose acetate me te hydroxypropylmethylcellulose propionate. A, no te iti te nui o te whakarewa, ka whakaiti i te whakawhänui o te mekameka macromolecular me te viscosity o te pünaha, kia heke iho te tohu o te esterification o te pünaha tauhohenga, ka heke te hua hei papatipu nui. A, ki te iti rawa te nui o te whakarewa, ka ngawari te whakakoi o te reactant ki roto i te puranga ka piri ki te pakitara ipu, ehara i te mea e pai ana mo te kawe i te tauhohenga, engari he nui te raru ki te maimoatanga i muri i te tauhohenga. . I roto i te whakahiato o te hydroxypropyl methylcellulose acetate, ka taea te whiriwhiri i te nui o te whakarewa hei 150 mL/2 g; mo te whakahiato o te hydroxypropyl methylcellulose propionate, ka taea te whiriwhiri hei 80 mL/0.5 g.

2.2 Tātari tūāwhiorangi pōkākā

He tūtohi whakataurite pōkākā o te hydroxypropyl methylcellulose me te hydroxypropyl methylcellulose acetate. Ki te whakatauritea ki te rauemi mata, he tino kitea te huringa o te spectrogram infrared o te hua hydroxypropyl methylcellulose acetate. I roto i te tuāwhiorangi infrared o te hua, ka puta he tihi kaha i te 1740cm-1, e tohu ana i puta he roopu waro; i tua atu, ko te kaha o te tihi wiri totoro o te OH i te 3500cm-1 he iti ake i tera o te rauemi mata, i tohu hoki ko -OH He tauhohenga.

Ko te spectrogram infrared o te hua hydroxypropyl methylcellulose propionate kua tino rerekee ano ki te whakataurite ki te rauemi mata. I roto i te tuāwhiorangi infrared o te hua, ka puta he tihi kaha i te 1740 cm-1, e tohu ana i puta he roopu waro; i tua atu, ko te OH totoro wiri peak kaha i te 3500 cm-1 he tino iti iho i tera o te rauemi mata, i tohu hoki i tauhohe te OH.

2.3 Te whakatau i te tohu whakakapinga

2.3.1 Te whakatau i te tohu whakakapinga o te hydroxypropyl methylcellulose acetate

I te mea ko te hydroxypropyl methylcellulose e rua kotahi te OH i ia waeine, me te cellulose acetate he hua ka riro ma te whakakapi i te COCH3 mo te H i roto i te OH kotahi, ko te tohu morahi o te whakakapinga (Ds) he 2.

2.3.2 Te whakatau i te tohu whakakapinga o te hydroxypropyl methylcellulose propionate

2.4 Te whakarewatanga o te hua

Ko nga matū e rua i whakahiatohia he riterite nga ahuatanga o te wairewa, me te hydroxypropyl methylcellulose acetate he iti ake te whakarewa ake i te hydroxypropyl methylcellulose propionate. Ka taea te rewa te hua waihanga i roto i te acetone, te ethyl acetate, te acetone/wai ​​whakauru whakarewa, a he nui ake te whiriwhiri. I tua atu, ko te makuku kei roto i te acetone/wai ​​whakauru whakarewa ka taea e nga pärönaki cellulose te haumaru me te pai o te taiao ina whakamahia hei taonga whakakikorua.

3. Whakamutunga

(1) Ko nga tikanga whakahiato o te hydroxypropyl methylcellulose acetate e whai ake nei: 2.5 g o te hydroxypropyl methylcellulose, te anhydride acetic hei kaihoko esterification, 150 mL o te pyridine hei whakarewa, te pāmahana tauhohenga i te 110° C, me te wa tauhohenga 1 h.

(2) Ko nga tikanga whakahiato o te hydroxypropyl methylcellulose acetate ko: 0.5 g o te hydroxypropyl methylcellulose, propionic anhydride hei kaihoko whakamaarama, 80 mL o te pyridine hei whakarewa, te pāmahana tauhohenga i te 110°C, me te wa tauhohenga o te 2 .5 haora.

(3) Ko nga hua o te cellulose i whakahiatohia i raro i tenei ahuatanga e tika ana ki te ahua o nga paura pai me te tohu pai o te whakakapi, a ka taea te whakakore i enei waahanga e rua i roto i nga momo whakarewa pararopi penei i te ethyl acetate, acetone, me te acetone/wai.