Hydroxypropyl Methylcellulose (HPMC)ndi ether ya cellulose yosakhala ionic yomwe imagwiritsidwa ntchito kwambiri, yomwe imagwiritsidwa ntchito kwambiri muzomangamanga, mankhwala, chakudya, zokutira, ndi zina. Kukhazikika kwa magwiridwe antchito ake ndi khalidwe lake zimakhudza mwachindunji zotsatira za chinthu chomaliza; chifukwa chake, kuyesa mwadongosolo kwa HPMC panthawi yopanga ndi kugwiritsa ntchito ndikofunikira kwambiri.
1. Maonekedwe ndi Kuyesa Katundu Woyambira
Musanayese, chitsanzocho chimaonedwa kaye ndi maso. HPMC yapamwamba kwambiri iyenera kukhala ufa woyera kapena wosayera bwino womwe umatha kuyenda bwino, wopanda ziphuphu, fungo, kapena zinyalala. Yankho lake lamadzi liyenera kukhala lowonekera bwino kapena lopanda madontho pang'ono, lopanda zinthu zobisika. Pambuyo pake, kuchuluka kwa chinyezi chake kumatsimikiziridwa, nthawi zambiri pogwiritsa ntchito chowunikira chinyezi cha infrared kapena njira yowumitsa (njira yolemera yosasintha ya 105℃). Zogulitsa zoyenerera nthawi zambiri zimakhala ndi kuchuluka kwa chinyezi pansi pa 5%.
Kuzindikira kuchuluka kwa phulusa kumasonyeza kuchuluka kwa kuipitsidwa kwake kosapangidwa ndi zinthu zachilengedwe. Chitsanzocho chimayatsidwa mu uvuni wa muffle pa kutentha kwa 550℃ mpaka kulemera kofanana. Kuchuluka kwa phulusa nthawi zambiri kumafunika kuti kusapitirire 1.5%. Kuchuluka kwa phulusa kudzakhudza kuwonekera bwino kwa yankho ndi kukhazikika kwa kukhuthala kwake.
2. Kuyesa Kukhuthala
Kukhuthala ndi chimodzi mwa zizindikiro zofunika kwambiri za HPMC, zomwe zimatsimikizira mwachindunji kukhuthala kwake, kusunga madzi, ndi zotsatira zake popanga filimu. Kuyesa nthawi zambiri kumachitika pogwiritsa ntchito viscometer yozungulira (monga Brookfield viscometer) kapena Ubbelohde capillary viscometer.
Pa nthawi yoyesera, kuchuluka kwina (nthawi zambiri 2%) kwa yankho lamadzi la HPMC kumayesedwa pa kutentha komwe kwatchulidwa (nthawi zambiri 20 ± 0.1℃). Mitundu yosiyanasiyana ya HPMC ili ndi mitundu yosiyanasiyana ya kukhuthala, monga 400, 15000, ndi 100000 mPa·s. Kukhuthala komwe kwayesedwa kuyenera kugwirizana ndi mtundu wa mankhwala; apo ayi, zimasonyeza kuti mlingo wake wa polymerization kapena kusintha kwake ndi wosakhazikika.
3. Kuyesa kwa Mlingo Wosinthira (Kuchuluka kwa Methoxy ndi Hydroxypropoxy)
Kugwira ntchito kwa HPMC kumatsimikiziridwa makamaka ndi kuchuluka kwa zinthu zomwe zimalowa m'malo mwake.
Kuchuluka kwa methoxy (–OCH₃) kumakhudza kusungunuka, kutentha kwa gel, ndi ntchito ya pamwamba;
Kuchuluka kwa hydroxypropoxy (–OCH₂CHOHCH₃) kumakhudza kusinthasintha ndi kusunga madzi.
Njira zodziwira nthawi zambiri zimagwiritsa ntchito titration ya mankhwala kapena gas chromatography. Mwachitsanzo, pambuyo pa hydrolysis ya asidi, chitsanzocho chimatulutsa alcohols yofanana, yomwe kenako imafufuzidwa mozama pogwiritsa ntchito titration kapena chromatography. Zogulitsa zoyenerera za HPMC nthawi zambiri zimakhala ndi 19%–24% ya methoxyl ndi 4%–12% ya hydroxypropoxyl.
4. Kuyeza Kutentha kwa Gel
Makhalidwe a thermogelation a HPMC ndi chinthu chofunikira chomwe chimasiyanitsa ndi ma ether ena a cellulose. Pakuyesa, yankho lamadzi la HPMC limatenthedwa pang'onopang'ono ndikusunthidwa, ndipo kutentha komwe yankho limasintha kuchoka pa clear kupita ku turbid kumalembedwa ngati kutentha kwake kwa gel.
Kawirikawiri, HPMC yokhala ndi methoxyl yambiri imakhala ndi kutentha kochepa kwa gel, pomwe kuchuluka kwa hydroxypropoxyl kwambiri kumapangitsa kutentha kwakukulu kwa gel. Chizindikiro ichi chikukhudzana ndi kukhazikika kwa mankhwalawa pakugwiritsa ntchito monga matope omangira ndi zokutira mapiritsi.
5. Kuyesa kwa pH ndi Kusungunuka
Mukamaliza kukonza yankho la 2% la HPMC, pH yake imayesedwa pogwiritsa ntchito pH meter. Chiwerengero cha pH ndi 5.0–8.0. Pakati pa chiwerengerochi, HPMC ndi yokhazikika ndipo sidzakhudzidwa ndi zinthu zambiri zosapangidwa kapena zowonjezera.
Kuyesa kusungunuka kumayesa kuchuluka kwa kufalikira kwake ndi kusungunuka kwake m'madzi ozizira. HPMC yapamwamba iyenera kufalikira mofulumira ikasakanizidwa, ndikupanga yankho lofanana komanso lowonekera mkati mwa mphindi 30.
6. Kuzindikira Chiyero ndi Chidetso
Kuzindikira kuyera kumaphatikizapo makamaka mayeso a zitsulo zolemera, ma chloride, ma sulfate, ndi malire a tizilombo toyambitsa matenda.
Kuchuluka kwa zitsulo zolemera (monga Pb) sikuyenera kupitirira 20 ppm; kloridi ≤ 0.2%, sulfate ≤ 0.5%;
Pa mankhwala kapena chakudya, chiwerengero chonse cha mabakiteriya, mabakiteriya a coliform, ndi chiwerengero cha nkhungu/yisiti chiyeneranso kuyesedwa kuti zitsimikizire kuti ndi zotetezeka.
7. Kusanthula kwa Thermogravimetric ndi Fourier Transform Infrared Spectroscopy
Kuti muwunikire bwino kapangidwe kake ndi kukhazikika kwa kutentha kwa HPMC, kusanthula kwa thermogravimetric (TGA) ndi Fourier transform infrared spectroscopy (FTIR) zingagwiritsidwe ntchito.
TGA imatha kuzindikira kusintha kwa HPMC pa kutentha kosiyanasiyana, motero imazindikira kutentha kwake komwe kumawola kutentha komanso kuchuluka kwa kukhazikika;
FTIR imasanthula kapangidwe ka gulu logwira ntchito kudzera m'magawo oyambira kuyamwa, kutsimikizira kukhalapo kwa magulu oyambira kuyamwa a –OH, –OCH₃, ndi –OCH₂CHOHCH₃ kuti atsimikizire kulondola kwa kapangidwe ka mamolekyu.
Kuyesa kwadongosolo komwe kwatchulidwa pamwambapa kumalola kuwunika kwathunthu kwa mphamvu za physicochemical ndi kuyenerera kwa HPMC kugwiritsa ntchito. Kukhuthala, kuchuluka kwa kusintha, ndi kuchuluka kwa chinyezi ndi zizindikiro zazikulu zowongolera khalidwe; pomwe pH, kuchuluka kwa phulusa, ndi kutentha kwa gelation zimasonyeza kuchuluka kwa kukonza ndi kuyera kwake. Kutsatira kwambiri njira zoyeserazi sikungotsimikizira kukhazikika kwa chinthucho komanso magwiridwe antchito ake komanso kumapereka chithandizo chodalirika cha deta kuti chikhale chotetezeka komanso chotetezeka.kugwiritsa ntchito bwino HPMCm'mafakitale monga zomangamanga, mankhwala, ndi chakudya.
Nthawi yotumizira: Okutobala-31-2025