Yiziphi izakhiwo ezishisayo ze-hydroxypropyll methylcellulose?

I-Hydroxypropyl Methylcellulose (HPMC) iyinhlangano eguquguqukayo enezinhlobonhlobo zezicelo ezimbonini ezahlukahlukene, kubandakanya nemithi, ukudla, ukwakhiwa kanye nezimonyo. Lapho ucubungula izakhiwo zayo ezishisayo, kubalulekile ukudonsa ekuziphatheni kwayo maqondana nezinguquko zokushisa, ukuqina okushisayo, kanye nanoma yisiphi isehlakalo esihlobene.

Ukuqina okushisayo: I-HPMC ibonisa ukuqina okuhle okushisayo ngaphezulu kwebanga lokushisa elibanzi. Ivame ukubola emazingeni okushisa aphezulu, ngokuvamile ngenhla kwama-200 ° C, kuya ngesisindo sayo samangqamuzana, izinga lokufaka esikhundleni, nezinye izinto. Inqubo yokucekelwa phansi ifaka phakathi i-cleavage ye-cellulose backbone kanye nokukhishwa kwemikhiqizo eguquguqukayo yokubola.

Ukushisa kwe-Glass Transion (TG): Njengama-polymers amaningi, i-HPMC ithola uguquko lwengilazi kusuka ku-glassy esimweni serejiya ngokushisa okukhuphukayo. I-TG ye-HPMC iyahlukahluka ngokuya ngezinga layo lokufakwa esikhundleni, isisindo se-molecular, kanye nomswakama okuqukethwe. Ngokuvamile, kusukela ku-50 ° C kuya ku-190 ° C. Ngaphezulu kwe-TG, i-HPMC iba nezimo ngokwengeziwe futhi kukhombisa ukukhuphuka kwamangqamuzana.

Iphoyinti elincibilikayo: I-HPMC ehlanzekile ayinalo iphuzu elihlukile lokuncibilika ngoba liyi-amorphous polymer. Kodwa-ke, kuyathambisa futhi kungageleza emazingeni okushisa aphakeme. Ukuba khona kwezithasiselo noma ukungcola kungathinta ukusebenza kwayo okuncibilikayo.

Ukuvuselelwa okushisayo: I-HPMC inokuphakelayo okushisayo okuphansi okuqhathaniswa nezinsimbi namanye amanye ama-polymers. Le mpahla yenza ukuthi ilungele izinhlelo zokusebenza ezidinga ukufakwa okushisayo, njengasezibhebheni zezemithi noma ezintweni zokwakha.

Ukunwetshwa kwe-Thermal: Njengama-polymers amaningi, i-HPMC inwebeka lapho kufuthelwa kanye nezinkontileka lapho kupholile. I-coefficient yokunwetshwa kwe-thermal (CTE) ye-HPMC incike ezintweni ezifana nokwakheka kwamakhemikhali kanye nezimo zokucubungula. Ngokuvamile, ine-CTE ebangeni le-100 kuye ku-300 ppm / ° C.

Umthamo wokushisa: Amandla okushisa we-HPMC athonywa yisakhiwo sawo samangqamuzana, izinga lokufakwa esikhundleni salo, kanye nokuqukethwe komswakama. Imvamisa isukela ku-1.5 kuye ku-2,5 j / g ° C. Ama-degree aphezulu wokufakwa esikhundleni kanye nokuqukethwe komswakama kuvame ukukhulisa umthamo wokushisa.

Ukuwohloka okushisayo: Lapho kuvezwa amazinga okushisa aphezulu ezikhathi ezinde, i-HPMC ingahle ibe nokuwohloka okushisayo. Le nqubo ingaholela ekushintsheni kwesakhiwo sayo samakhemikhali, okuholela ekulahlekelweni kwezindawo ezinjengokusobala namandla emishini.
Ukuthuthukiswa kwe-Thermal Treatity: I-HPMC ingashintshwa ukuze ithuthukise ukuthuthuka kwayo okushisayo kwezicelo ezithile. Ukufaka ama-filler noma izengezo, njengezinhlayiya zensimbi noma izinhlayiya ze-carbon, kungathuthukisa izakhiwo zokudlulisa ukushisa, okwenza kube lula ukuthola izinhlelo zokusebenza ezishisayo.

Izicelo: Ukuqonda izakhiwo ezishisayo ze-HPMC zibalulekile ukwenza kahle ukusetshenziswa kwayo ezinhlelweni ezahlukahlukene. Emikhakheni, isetshenziswa njenge-binder, ifilimu yangaphambili, ne-ejenti yokukhishwa kwethebhulethi. Ekwakhiweni, kuqashwa ezintweni ezisetshenziselwa ukhula ukuze kwenziwe ngcono ukusebenza, ukunamathela, kanye nokugcinwa kwamanzi. Ekudleni nasezimonyo, kusebenza njengesikhulu, i-stabilizer kanye ne-emulsifier.

I-Hydroxypropyl methylcellulose (HPMC) ibonisa uhla lwezakhiwo ezishisayo ezikwenza ilungele izinhlelo zokusebenza ezahlukahlukene kuyo yonke imboni. Ukuqina kwayo okushisayo, izinga lokushisa le-glass, ukuqina okushisayo, nezinye izici kudlala indima enkulu ekunqumeni ukusebenza kwayo ezindaweni ezithile kanye nezicelo. Ukuqonda lezi zakhiwo kubalulekile ekusetshenzisweni okusebenzayo kwe-HPMC emikhiqizweni ehlukahlukene nezinqubo.