Hydroxypropyl methylcellulose (HPMC) wani abu ne da ake amfani da shi wajen sarrafa sinadarai masu narkewa cikin ruwa wanda ake amfani da shi sosai a fannin magani, abinci, gini da sauran fannoni. Yana da kyakkyawan kwanciyar hankali na zafi, amma har yanzu yana iya lalacewa a ƙarƙashin yanayin zafi mai yawa. Yanayin zafi na HPMC galibi yana shafar tsarin kwayoyin halittarsa, yanayin muhalli (kamar danshi, ƙimar pH) da lokacin dumama.
Zafin jiki na lalacewa na HPMC
Lalacewar zafi na HPMC yawanci yakan fara bayyana sama da digiri 200℃, kuma rugujewar bayyananne za ta faru tsakanin 250℃-300℃Musamman:
Ƙasa da 100℃: HPMC galibi yana nuna ƙafewar ruwa da canje-canje a cikin halayen jiki, kuma babu wani lalacewa da ke faruwa.
100℃-200℃: HPMC na iya haifar da wani ɓangare na iskar shaka saboda ƙaruwar zafin jiki na gida, amma gabaɗaya yana da ƙarfi.
200℃-250℃: HPMC a hankali yana nuna lalacewar zafi, wanda galibi yana bayyana a matsayin karyewar tsari da sakin ƙananan ƙwayoyin cuta masu canzawa.
250℃-300℃: HPMC yana fuskantar ruɓewa a bayyane, launin ya yi duhu, ƙananan ƙwayoyin halitta kamar ruwa, methanol, acetic acid suna fitowa, sannan carbonation ya faru.
Sama da 300℃: HPMC yana raguwa da sauri kuma yana zama carbon, kuma wasu abubuwa marasa halitta suna nan a ƙarshe.
Abubuwan da ke shafar lalacewar HPMC
Nauyin kwayoyin halitta da matakin maye gurbinsu
Idan nauyin kwayoyin halittar HPMC ya yi yawa, yawan juriyarsa ga zafi yakan yi yawa.
Matsayin maye gurbin ƙungiyoyin methoxy da hydroxypropoxy zai shafi daidaiton zafinsa. HPMC mai babban matakin maye gurbin yana da sauƙin lalacewa a yanayin zafi mai yawa.
Abubuwan Muhalli
Danshi: HPMC yana da ƙarfin hygroscopicity, kuma danshi na iya hanzarta lalacewa a yanayin zafi mai yawa.
Darajar pH: HPMC ya fi saurin kamuwa da hydrolysis da lalacewa a ƙarƙashin yanayin acid mai ƙarfi ko alkaline.
Lokacin dumama
Dumamawa zuwa 250℃na ɗan gajeren lokaci ba zai iya ruɓewa gaba ɗaya ba, yayin da kiyaye zafin jiki mai yawa na dogon lokaci zai hanzarta tsarin ruɓewa.
Kayayyakin lalata na HPMC
Ana samun HPMC ne galibi daga cellulose, kuma samfuran lalatawarsa suna kama da cellulose. A lokacin dumama, ana iya fitar da waɗannan abubuwa:
Tururin ruwa (daga rukunin hydroxyl)
Methanol, ethanol (daga ƙungiyoyin methoxy da hydroxypropoxy)
Acetic acid (daga samfuran ruɓaɓɓu)
Carbon oxides (CO, CO)₂, wanda aka samar ta hanyar ƙona abubuwan halitta)
Ƙaramin adadin ragowar coke
Aikace-aikace zafi juriya na HPMC
Kodayake HPMC zai ragu a hankali sama da 200℃, yawanci ba a fallasa shi ga irin wannan yanayin zafi mai yawa a aikace-aikacen gaske. Misali:
Masana'antar harhada magunguna: Ana amfani da HPMC galibi don shafa kwayayen magani da kuma magungunan da ke dawwama, galibi ana aiki da su a digiri 60.℃-80℃, wanda ya yi ƙasa da zafin lalacewarsa sosai.
Masana'antar abinci: Ana iya amfani da HPMC azaman mai thickener ko emulsifier, kuma zafin amfani na yau da kullun yawanci ba fiye da 100 ba℃.
Masana'antar gini: Ana amfani da HPMC a matsayin abin kauri na siminti da turmi, kuma zafin ginin gabaɗaya baya wuce 80℃, kuma babu wani raguwa da zai faru.
HPMC yana fara lalacewa da zafi sama da 200℃, yana wargaza sosai tsakanin 250℃-300℃, kuma yana carbonize da sauri sama da digiri 300℃A aikace-aikace na zahiri, ya kamata a guji fuskantar yanayi mai zafi na dogon lokaci don kiyaye aikinsa mai dorewa.
Lokacin Saƙo: Afrilu-03-2025