Hydroxypropylmethylcellulose (HPMC) ndi pawiri yomwe yakhala yofunika kwambiri m'mafakitale ambiri chifukwa cha ntchito zake zambiri. Nthawi zambiri amagwiritsidwa ntchito ngati chowonjezera chakudya, chowonjezera mu zodzoladzola, komanso ngati mankhwala opangira mankhwala ambiri. A wapadera katundu wa HPMC ake thixotropic khalidwe, amene amalola kusintha mamasukidwe akayendedwe ndi otaya katundu pansi zina. Komanso, onse mkulu mamasukidwe akayendedwe ndi otsika mamasukidwe akayendedwe HPMC ndi katundu, kusonyeza thixotropy ngakhale pansi kutentha gel osakaniza.
Thixotropy imapezeka mu HPMC pamene yankho limakhala lometa ubweya wa ubweya pamene kupanikizika kumagwiritsidwa ntchito kapena kugwedezeka, zomwe zimapangitsa kuchepa kwa viscosity. Khalidweli lingathenso kusinthidwa; pamene kupsinjika kumachotsedwa ndipo yankho limasiyidwa kuti lipume, kukhuthala kumabwerera pang'onopang'ono kumalo ake apamwamba. Katundu wapaderawa amapangitsa HPMC kukhala chinthu chofunikira m'mafakitale ambiri chifukwa imalola kugwiritsa ntchito bwino komanso kukonza kosavuta.
Monga nonionic hydrocolloid, HPMC imatupa m'madzi kupanga gel. Kuchuluka kwa kutupa ndi gelling kumadalira kulemera kwa maselo ndi ndende ya polima, pH ndi kutentha kwa yankho. High mamasukidwe akayendedwe HPMC zambiri ali mkulu maselo kulemera ndi kumapanga mkulu mamasukidwe gel osakaniza, pamene otsika mamasukidwe akayendedwe HPMC ali otsika molecular kulemera ndipo umapanga gel osakaniza viscous. Komabe, ngakhale kusiyana kumeneku kwa magwiridwe antchito, mitundu yonse ya HPMC imawonetsa thixotropy chifukwa cha kusintha kwamapangidwe komwe kumachitika pamlingo wa maselo.
Khalidwe la thixotropic la HPMC ndi chifukwa cha kuyanjanitsa kwa maunyolo a polima chifukwa cha kumeta ubweya wa ubweya. Pamene kumeta ubweya wa tsitsi kumagwiritsidwa ntchito ku HPMC, maunyolo a polima amagwirizana kumbali ya kupanikizika komwe kumagwiritsidwa ntchito, zomwe zimapangitsa kuti pakhale kuwonongeka kwa mawonekedwe a maukonde atatu omwe analipo popanda kupanikizika. Kusokonezeka kwa maukonde kumabweretsa kuchepa kwa kukhuthala kwa yankho. Kupsyinjika kumachotsedwa, maunyolo a polima amakonzanso motsatira momwe adayambira, kumanganso maukonde ndikubwezeretsa kukhuthala.
HPMC imasonyezanso thixotropy pansi pa kutentha kwa gelling. Kutentha kwa gel ndi kutentha komwe maunyolo a polima amadutsana kuti apange maukonde amitundu itatu, kupanga gel. Zimatengera ndende, kulemera kwa maselo ndi pH ya yankho la polima. Gel chifukwa chake chimakhala ndi kukhuthala kwakukulu ndipo sichimasintha mofulumira pansi pa kupanikizika. Komabe, pansi pa kutentha gelation, ndi HPMC njira anakhalabe madzi, komabe anasonyeza thixotropic khalidwe chifukwa cha kukhalapo kwa pang'ono anapanga maukonde dongosolo. Maukonde opangidwa ndi magawowa amasweka ndi kupsinjika, zomwe zimapangitsa kuchepa kwa mamasukidwe akayendedwe. Khalidweli ndi lopindulitsa m'mapulogalamu ambiri pomwe mayankho amafunikira kuyenda mosavuta akagwedezeka.
HPMC ndi zosunthika mankhwala ndi angapo wapadera katundu, mmodzi wa iwo ndi khalidwe thixotropic. Ma HPMC onse apamwamba kwambiri komanso otsika-makamaka ali ndi katunduyu, akuwonetsa thixotropy ngakhale pansi pa kutentha kwa gel osakaniza. Khalidweli limapangitsa HPMC kukhala gawo lofunikira m'mafakitale ambiri omwe amafunikira mayankho omwe amawongolera kuyenda kosavuta kuti atsimikizire kugwiritsa ntchito bwino. Ngakhale kusiyana katundu pakati mkulu-makamaka mamasukidwe akayendedwe otsika mamasukidwe akayendedwe HPMCs, awo thixotropic khalidwe limapezeka chifukwa cha mayikidwe ndi kusokonezeka kwa pang'ono anapanga maukonde dongosolo. Chifukwa cha mawonekedwe ake apadera, ofufuza akufufuza nthawi zonse ntchito zosiyanasiyana za HPMC, akuyembekeza kupanga zatsopano ndikupereka mayankho abwino kwa ogula padziko lonse lapansi.
Nthawi yotumiza: Aug-23-2023