Nā waiwai kemika o HPMC

ʻO ka Hydroxypropyl Methylcellulose (HPMC)He ʻetera cellulose non-ionic ia, he huahana i hoʻololi ʻia i ke kemika i hoʻokumu ʻia e ka hopena o ka cellulose kūlohelohe me ka propylene oxide a me ka methyl chloride ma hope o ka alkalization. Loaʻa iā HPMC ke kūpaʻa kino a me ke kemika maikaʻi a hoʻohana nui ʻia i nā lāʻau lapaʻau, nā mea kūkulu hale, ka meaʻai, nā mea hoʻonani a me nā ʻoihana ʻē aʻe. Eia kona mau waiwai kemika:

1. Nā ʻano hoʻonohonoho molekala

ʻO ke kumu o ka iwi o ka HPMC mai ka cellulose kūlohelohe, i hana ʻia e nā ʻāpana glucose i hoʻopili ʻia e nā pilina β-1,4-glycosidic e hana i kahi kaulahao macromolecular linear. ʻO ka hoʻolauna ʻana o nā hui hydroxypropyl a me methoxy e pani hapa i nā hui hydroxyl (-OH) ma ke kaulahao molekala cellulose, a laila e hāʻawi ana iā ia i nā waiwai kū hoʻokahi. ʻO kēia kekelē o ka pani ʻana (ʻo ia hoʻi, ke kekelē o ka pani ʻana o nā hui methoxy a me hydroxypropyl) he mana koʻikoʻi ia i ka solubility, nā waiwai gel a me ke kūpaʻa o HPMC.

2. Ka hiki ke hoʻoheheʻe ʻia

He polymer wai-soluble non-ionic maʻamau ka HPMC i hiki ke pehu koke i ka wai anuanu a hana i kahi hopena colloidal moakaka a translucent paha. Eia nō naʻe, i ka wai wela, ʻaʻole maʻalahi ka hoʻoheheʻe ʻana o HPMC a e hana i kahi gel i nā mahana kiʻekiʻe. ʻO kēia waiwai gel thermoreversible kekahi o nā waiwai kino a me nā kemika koʻikoʻi o HPMC. Ma waho aʻe o ka wai, hiki ke hoʻoheheʻe ʻia ka HPMC i loko o kekahi mau mea hoʻoheheʻe organik polar, e like me ka mea hoʻoheheʻe i hui ʻia o ka ethanol a me ka wai, dimethylformamide, a pēlā aku.

3. Paʻa wela a me ka gelation

Loaʻa i ka HPMC ke kūpaʻa wela maikaʻi loa. Ke piʻi ka mahana, e pili ana nā kaulahao molekala HPMC i loko o ka wai wai i ka hui dehydration e hana i kahi ʻano pūnaewele ʻekolu-dimensional, a e hana ʻia kahi hoʻololi mai ka hopena i ka gel. Aia ka mahana gelation i ka ʻike a me ke kaumaha molekala o nā substituents. Ma ke ʻano laulā, ʻoi aku ka mahana gelation o ka HPMC me ka ʻike hydroxypropyl kiʻekiʻe, ʻoiai ʻo ka HPMC me ka ʻike methoxy kiʻekiʻe he haʻahaʻa ka mahana gelation.

Hiki ke hoʻohuli ʻia ka Gelation, a e hoʻihoʻi ka gel i loko o kahi wai ma hope o ka hoʻomaʻalili ʻana. ʻO kēia waiwai thermogel kū hoʻokahi e hoʻohana pinepine ai ʻo HPMC ma ke ʻano he mea hoʻokuʻu mau i ka ʻoihana lāʻau lapaʻau a hoʻohana ʻia i ka ʻoihana mea kūkulu hale e hoʻomaikaʻi i ka hana kūkulu o ka mortar.

4. kūpaʻa pH

Mālama ʻo HPMC i ke kūpaʻa maikaʻi ma ka pae pH o 3 ~ 11. ʻO kēia pae kūpaʻa pH ākea e ʻae iā ia e hoʻohana ʻia ma nā ʻano ʻano like ʻole me ka ʻole o ka hōʻino ʻia a i ʻole ka ua. Ke haʻahaʻa ka waiwai pH ma mua o 3 a ʻoi aku paha ma mua o 11, hiki ke hōʻino ʻia a hoʻopūʻiwa ʻia paha ka hopena ma muli o ke kiʻekiʻe o nā ion hydrogen a i ʻole nā ​​ion hydroxide, e hopena ana i ka emi ʻana o ka hana.

5. Ka Hana Kemika

Ma muli o ke alo o kekahi mau hui hydroxyl i hoʻololi ʻole ʻia i loko o ka molekole HPMC, mālama mau ia i kahi hana kemika a hiki ke hana i nā hopena penei:

Ka hopena Esterification: Ma lalo o nā kūlana kūpono, hiki i ka HPMC ke hana me nā acyl chlorides, anhydrides, a me nā mea ʻē aʻe e hana i nā esters;

ʻO ka hopena Etherification: Hiki i nā hui hydroxyl koena ke hoʻomau i ka hana me nā mea etherifying (e like me nā epoxides) e hoʻololi hou i ke kiʻekiʻe o ka pani ʻana a me ka hana o HPMC;

Ka hopena oxidation: I ke alo o nā oxidants ikaika (e like me ka potassium permanganate, sodium hypochlorite), hiki ke haki ke kaulahao molekala o HPMC, e hopena ana i ka emi ʻana o ka viscosity;

Ka hopena hydrolysis: Ma lalo o ka hana a nā waikawa ikaika a i ʻole nā ​​​​kumu ikaika, hiki ke hydrolyzed ʻia nā kaulahao ʻaoʻao hydroxypropyl a me methoxy, e hana ana i nā loli i ke ʻano molekala a me ka hoʻohaʻahaʻa hana.

Ma keʻano laulā, ma lalo o nā kūlana noi maʻamau, ua paʻa loa nā waiwai kemika o HPMC.

6. Ka palaho ʻana o ka ʻiole

Loaʻa ka HPMC mai ka cellulose kūlohelohe, no laila hiki ke hoʻohaʻahaʻa ʻia i loko o nā kō molekala liʻiliʻi i loko o kahi ʻano olaola kikoʻī (e like me ka hana a nā microorganism), a laila hoʻohaʻahaʻa hope ʻia i loko o ke kalapona ʻokikene a me ka wai. ʻO kēia biodegradability maikaʻi e hoʻokō ai ka HPMC i nā koi o nā mea pili i ke kaiapuni.

7. Ka kūlike me nā mea ʻē aʻe

Ma ke ʻano he polymer non-ionic, loaʻa i ka HPMC kahi kūlike maikaʻi me nā ʻano mea hoʻohui ionic a non-ionic paha (e like me nā polymers ʻē aʻe, nā surfactants, nā thickeners, a me nā mea ʻē aʻe). ʻOi loa i ka ʻōnaehana hoʻohui, hiki iā ia ke hana me nā ʻano mea hoʻohui lāʻau like ʻole, nā meaʻai, nā pigments, a me nā mea ʻē aʻe me ka ʻole o ka ua a i ʻole ka stratification.

e hoʻopilikia ʻia ke kūpaʻa o HPMC i loko o kahi kaiapuni electrolyte kiʻekiʻe, a ʻo ka nui o ka paʻakai inorganic e hoʻemi ai i ka viscosity o ka hopena a i ʻole e precipitate.

8. Ke kū'ē ʻana i ka enzyme

Ke hoʻohālikelike ʻia me ka cellulose kūlohelohe,HPMCua hoʻonui ʻia ke kū'ē ʻana i ka cellulase ma muli o ka hoʻololi ʻana o kekahi mau hui hydroxyl, a ʻaʻole maʻalahi e hoʻopau ʻia e nā enzymes maʻamau. Hāʻawi kēia hiʻohiʻona iā ia i ka pono o ka hoʻokuʻu lohi ʻana o nā lāʻau lapaʻau i loko o ke kaiapuni gastrointestinal.

ʻO Hydroxypropyl methylcellulose (HPMC) kahi mea polymer kūlohelohe i hoʻololi ʻia e ke kemika me ka solubility wai maikaʻi, ka gelation thermal, ka paʻa pH, ka paʻa kemika a me ka biodegradability. Ma muli o kona ʻano kū hoʻokahi a me nā waiwai kemika, hoʻohana nui ʻia ka HPMC ma nā kahua o ka lāʻau lapaʻau, nā mea kūkulu hale, nā uhi, ka meaʻai, nā mea hoʻonani, a me nā mea ʻē aʻe, ʻoi aku hoʻi i nā ʻano hana e pono ai ka mānoanoa, ka hoʻokuʻu ʻana i kāohi ʻia, ka hoʻokumu ʻana i ka ʻili, ka hoʻokuʻu ʻana, ka emulsification a me nā hana ʻē aʻe.