Hydroxypropyl methylcellulose (HPMC) ndi non-ayoni madzi sungunuka polima pawiri wopezedwa ndi kusinthidwa mankhwala achilengedwe mapadi. Amagwiritsidwa ntchito kwambiri m'mafakitale azakudya, zamankhwala, zodzoladzola ndi zomangamanga, makamaka ngati zomatira, zonenepa, zokometsera komanso zoyimitsa pokonzekera mankhwala. Pogwiritsa ntchito, mawonekedwe a viscosity ya HPMC amadzimadzi amadzimadzi ndi ofunika kwambiri pakuchita kwake m'magawo osiyanasiyana.
1. Mapangidwe ndi katundu wa hydroxypropyl methylcellulose
Mapangidwe a maselo a HPMC ali ndi magulu awiri olowa, hydroxypropyl (-CH₂CHOCH₃) ndi methyl (-OCH₃), zomwe zimapangitsa kuti zikhale ndi madzi abwino kusungunuka komanso kusinthika. The HPMC molekyulu unyolo ali ena okhwima dongosolo, koma akhoza kupanga atatu azithunzithunzi maukonde dongosolo mu amadzimadzi njira, kuchititsa kuwonjezeka mamasukidwe akayendedwe. Kulemera kwake kwa mamolekyulu, mtundu wa cholowa m'malo ndi kuchuluka kwa m'malo (mwachitsanzo, kuchuluka kwa hydroxypropyl ndi kusintha kwa methyl pagawo lililonse) kumakhudza kwambiri kukhuthala kwa yankho.
2. Viscosity makhalidwe a amadzimadzi njira
Makhalidwe a mamasukidwe akayendedwe a HPMC amadzimadzi amadzimadzi amagwirizana kwambiri ndi zinthu monga ndende, kulemera kwa maselo, kutentha ndi pH mtengo wa zosungunulira. Nthawi zambiri, mamasukidwe akayendedwe a HPMC amadzimadzi njira kumawonjezeka ndi kuwonjezeka ndende yake. Kukhuthala kwake kumasonyeza khalidwe losakhala la Newtonian rheological, ndiko kuti, pamene kumeta ubweya wa ubweya ukuwonjezeka, kukhuthala kwa yankho kumachepa pang'onopang'ono, kusonyeza kumeta ubweya wonyezimira chodabwitsa.
(1) Zotsatira za kuika maganizo pa zinthu
Pali ubale wina pakati pa mamasukidwe akayendedwe a HPMC amadzimadzi yankho ndi ndende yake. Pamene chiwerengero cha HPMC chikuwonjezeka, kuyanjana kwa ma molekyulu mu njira yamadzimadzi kumawonjezeka, ndipo kutsekemera ndi kugwirizanitsa kwa unyolo wa maselo kumawonjezeka, zomwe zimabweretsa kuwonjezeka kwa viscosity ya yankho. Pazigawo zotsika, kukhuthala kwa HPMC yamadzimadzi kumawonjezeka mofanana ndi kuwonjezeka kwa ndende, koma pazigawo zapamwamba, kukula kwa viscosity kwa yankho kumakhala kosalala ndipo kumafika pamtengo wokhazikika.
(2) Zotsatira za kulemera kwa maselo
The molecular kulemera kwa HPMC mwachindunji zimakhudza mamasukidwe akayendedwe ake amadzimadzi njira. HPMC yokhala ndi kulemera kwakukulu kwa maselo imakhala ndi maunyolo aatali a maselo ndipo imatha kupanga mawonekedwe ovuta kwambiri amitundu itatu mu njira yamadzimadzi, zomwe zimapangitsa kukhuthala kwapamwamba. Mosiyana ndi izi, HPMC yokhala ndi kulemera kochepa kwa maselo imakhala ndi maukonde omasuka komanso ma viscosity otsika chifukwa cha unyolo wake wamfupi. Choncho, pamene ntchito, n'kofunika kwambiri kusankha HPMC ndi oyenera maselo kulemera kukwaniritsa abwino mamasukidwe akayendedwe kwenikweni.
(3) Zotsatira za kutentha
Kutentha ndi chinthu chofunikira chomwe chikukhudza mamasukidwe amadzimadzi a HPMC. Pamene kutentha kumawonjezeka, kuyenda kwa mamolekyu amadzi kumawonjezeka ndipo kukhuthala kwa yankho kumachepa. Izi zili choncho chifukwa kutentha kumakwera, ufulu wa HPMC unyolo wa maselo ukuwonjezeka ndipo kuyanjana pakati pa mamolekyu kumafooketsa, motero kuchepetsa kukhuthala kwa yankho. Komabe, kuyankha kwa HPMC kuchokera kumagulu osiyanasiyana kapena mitundu yosiyanasiyana kutentha kumathanso kusiyanasiyana, chifukwa chake kutentha kumafunika kusinthidwa malinga ndi zofunikira za ntchito.
(4) Zotsatira za pH mtengo
HPMC palokha ndi sanali ionic pawiri, ndi mamasukidwe akayendedwe ake amadzimadzi yankho tcheru kusintha pH. Ngakhale HPMC imawonetsa mawonekedwe okhazikika a viscosity m'malo okhala acidic kapena osalowerera ndale, kusungunuka ndi kukhuthala kwa HPMC kudzakhudzidwa m'malo amchere kwambiri kapena amchere. Mwachitsanzo, pansi pa asidi amphamvu kapena zinthu zamphamvu zamchere, mamolekyu a HPMC amatha kuchepetsedwa pang'ono, potero amachepetsa kukhuthala kwa njira yake yamadzimadzi.
3. Rheological analysis of viscosity makhalidwe a HPMC amadzimadzi njira
The rheological khalidwe la HPMC amadzimadzi njira zambiri zimasonyeza sanali Newtonian madzimadzi makhalidwe, kutanthauza kuti mamasukidwe akayendedwe ake si zokhudzana ndi zinthu monga njira ndende ndi maselo kulemera, komanso kumeta ubweya mlingo. Nthawi zambiri, pamitengo yotsika yometa ubweya, njira yamadzi ya HPMC imawonetsa kukhuthala kwapamwamba, pomwe kuchuluka kwa kukameta ubweya kumawonjezeka, kukhuthala kumachepa. Khalidweli limatchedwa "kumeta ubweya wa ubweya" kapena "kumeta ubweya" ndipo ndilofunika kwambiri pazochitika zambiri. Mwachitsanzo, m'minda ya zokutira, kukonzekera mankhwala, kukonza chakudya, ndi zina zotero, kumeta ubweya wa ubweya wa HPMC kungathe kuonetsetsa kuti kukhuthala kwapamwamba kumasungidwa panthawi yogwiritsira ntchito mofulumira, ndipo kumatha kuyenda mosavuta pansi pamikhalidwe yothamanga kwambiri.
4. Zinthu zina zomwe zimakhudza kukhuthala kwa HPMC yamadzimadzi
(1) Mphamvu ya mchere
Kuwonjezera mchere solutes (monga sodium kolorayidi) kuonjezera mamasukidwe akayendedwe a HPMC amadzimadzi njira. Izi ndichifukwa choti mchere ukhoza kupititsa patsogolo kuyanjana pakati pa mamolekyu posintha mphamvu ya ayoni ya yankho, kuti mamolekyu a HPMC apange mawonekedwe ophatikizika kwambiri, potero akuwonjezera kukhuthala. Komabe, zotsatira za mtundu wa mchere ndi ndende pa viscosity zimafunikanso kusinthidwa malinga ndi zochitika zenizeni.
(2) Zotsatira za zowonjezera zina
Kuonjezera zina (monga surfactants, ma polima, etc.) kuti HPMC amadzimadzi njira zidzakhudzanso mamasukidwe akayendedwe. Mwachitsanzo, surfactants akhoza kuchepetsa mamasukidwe akayendedwe a HPMC, makamaka pamene surfactant ndende ndi mkulu. Kuphatikiza apo, ma polima ena kapena tinthu tating'onoting'ono amathanso kucheza ndi HPMC ndikusintha mawonekedwe a rheological a yankho lake.
Makhalidwe a mamasukidwe akayendedwe ahydroxypropyl methylcellulose njira amadzimadzi amakhudzidwa ndi zinthu zambiri, kuphatikizapo ndende, maselo kulemera, kutentha, pH mtengo, etc. HPMC amadzimadzi njira zambiri zimasonyeza sanali Newtonian rheological katundu, ali thickening wabwino ndi kukameta ubweya kupatulira katundu, ndipo chimagwiritsidwa ntchito zosiyanasiyana mafakitale ndi mankhwala minda. Kumvetsetsa ndikuzindikira mawonekedwe a viscosity izi kumathandizira kukhathamiritsa kugwiritsa ntchito HPMC pazogwiritsa ntchito zosiyanasiyana. Muzogwiritsira ntchito, mtundu woyenera wa HPMC ndi machitidwe a ndondomeko ayenera kusankhidwa malinga ndi zosowa zenizeni kuti apeze kukhuthala koyenera komanso katundu wa rheological.
Nthawi yotumiza: Mar-01-2025