Hydroxypropyl methylcellulose (hpmc)Ndi malo osungunuka osungunuka omwe amagwiritsidwa ntchito pomanga, mankhwala, chakudya ndi mafakisoni. Ndiwosagwiritsa ntchito ma cellulose ether ether etted ndi kusintha kwa mankhwala a cellulose wachilengedwe, ndikukula bwino, emulsization, kukhazikika ndi mawonekedwe a filimu. Komabe, pansi pa kutentha kwambiri, HPMC idzawonongeka kwamafuta, komwe kumakhala kofunikira pakukhazikika kwake ndikugwirira ntchito pakugwiritsa ntchito.
Njira yochepetsera mafuta ya HPMC
Kuwonongeka kwa matenthedwe a HPMC makamaka kumaphatikizapo kusintha kwakuthupi ndi kusintha kwamankhwala. Kusintha kwakuthupi kumawonekera makamaka ngati kusintha madzi, kusintha kwagalasi ndi kuchepetsedwa kwa ma vina, pomwe kusintha kwa mankhwala kumakhudza kuwonongeka kwa kapangidwe kake, kapangidwe ka kapangidwe ka kapangidwe ka kapangidwe ka kayendedwe ka mpweya.
1. Gawo lotentha lochepa (100-200 ° C): Madzi am'madzi ndi kuwola koyamba
Pansi pa kutentha kochepa (pafupifupi 100 ° C), HPMC makamaka kumapangitsa madzi kutuluka ndi galasi. Popeza HPMC ili ndi madzi omanga, madzi awa amayamba kutuluka pang'onopang'ono pakutentha, motero amakhudza miyambo yake yanyengo. Kuphatikiza apo, mafayilo a HPMC amachepetsa ndi kuchuluka kwa kutentha. Zosintha mu gawo ili zimasintha kwambiri thupi, pomwe mawonekedwe a mankhwala amasintha.
Kutentha kukupitilizabe mpaka kufika 150-200 ° C, HPMC kumayamba kuwonongeka kokha kwamankhwala koyambirira. Zimawonekera makamaka pakuchotsa kwa hydroxypyl ndi methoxy magwiridwe antchito, zomwe zimapangitsa kuchepa kwa mapangidwe a ma celecular ndi kusintha kwa kapangidwe kake. Pakadali pano, hpmc imatha kubweretsa mamolekyulu ochepa osasunthika, monga methanol ndi proliquionaldehyde.
2. Gawo lotentha (200-300 ° C): Kodi kuwonongeka kwakukulu ndi m'badwo wawung'ono wa Molekyu
Kutentha kumawonjezeka mpaka 200-300 ° C, kuwonongeka kwa HPMC kumapitilira kwakukulu. Njira zowonongeka zazikulu zimaphatikizapo:
Ether Conseorged Sturm: Tsitsi lalikulu la HPMC limalumikizidwa ndi ma elucose mphete, ndipo zomangira za Ether mkati mwake zimapuma pansi pa kutentha kwambiri, zomwe zimapangitsa unyolo wa polymer kuti muwongolere.
Kuchita mwanzeru: Kapangidwe ka shuga kwa HPMC kungayambitse matenda osokoneza bongo pamtunda wambiri kuti apange pakatikati, komwe kumawola ku zinthu zosasunthika.
Kumasulidwa kwa ma molekyulu ang'onoang'ono: Panthawi imeneyi, hpmc imatulutsa co, coce, h₂o ndi ma molekyulu okhazikika, monga formaldehyde, acetaldehyde ndi acrolein.
Kusintha kumeneku kudzapangitsa kuti ma molecular kulemera kwa hpmc kuti agwetse kwambiri, mamasukidwe otukula kwambiri, ndipo zinthuzo ziyamba kutembenukira chikasu ngakhale kumapanga zophika.
3. Gawo lotentha kwambiri (300-500 ° C): Cabonization ndi kuphika
Matenthedwe akakwera pamwamba 300 ° C, hpmc amalowa mu gawo lachiwawa la kuwonongeka. Pakadali pano, kuswa kwinanso kwa unyolo waukulu ndi volatilizetion ya mankhwala ang'onoang'ono a molekyulu amatsogolera ku chiwonongeko chonsecho, kenako ndikupanga ma carbonalous otsalira (coke). Izi zimachitika makamaka pagawo ili:
Kuwonongeka Kwakuti: Kutentha kwambiri, hpmc kumachitika maxidation omwe amapanga co₂ ndi CO, ndipo nthawi yomweyo amapanga matebulo.
Kuchulukana: Gawo la kapangidwe ka polymer limasinthidwa kukhala zinthu zosakwanira, monga zotsalira zakuda kapena zotsalira.
Zosasintha: Pitilizani kumasula ma hydrocarbons monga Ethylene, Propylene, ndi Methane.
Atatenthedwa mlengalenga, hpmc amatha kuwotcha, pomwe mukutenthetsa mpweya chifukwa cha mpweya umakhala ndi zotsalira za kaboni.
Zinthu zomwe zimakhudza kuwonongeka kwa matenthedwe a HPMC
Kuwonongeka kwa matenthedwe kwa HPMC kumakhudzidwa ndi zinthu zambiri, kuphatikiza:
Kapangidwe ka mankhwala: Mlingo wazomera za hydroxypylll ndi methoxy magulu a HPMC amakhudzanso bata. Nthawi zambiri, ma hpmc omwe ali ndi vuto la hydroxypyl ali ndi bata labwino.
Mpweya wabwino: Mlengalenga, HPMC imakonda kuwonongeka kwa oxina (monga nayitrogeni), kuchuluka kwake kuwonongeka kwa mafuta ndi pang'onopang'ono.
Kutenthetsa Mtengo: Kutenthetsa mwachangu kumabweretsa kuwola kwachangu, pomwe pang'onopang'ono kumathandiza pang'onopang'ono kaboni pang'ono ndikuchepetsa kupanga kwa zinthu zosasunthika.
Zolemba: HPMC ili ndi madzi okwera. Mukamatenthetsa, kusintha kwa chinyezi kumakhudza kutentha kwake kagalasi ndi njira yowonongeka.
Ntchito zothandiza pakuwonongeka kwa matenthedwe a HPMC
Makhalidwe osokoneza bongo a HPMC ndi ofunika kwambiri mu gawo lake. Mwachitsanzo:
Makampani omanga: HPMC imagwiritsidwa ntchito mu matope a simenti ndi gypsum, ndipo kukhazikika kwake nthawi yamagetsi kumayenera kuonedwa kuti kupewa kuwonongeka.
Makampani ogulitsa mankhwala: HPMC ndi mankhwala omasulidwa mankhwala osokoneza bongo, ndipo kuwonongeka kumayenera kupewedwa pakupanga kutentha kwambiri kuonetsetsa kukhazikika kwa mankhwalawa.
Makampani ogulitsa zakudya: hpmc ndi chowonjezera cha chakudya, ndipo mawonekedwe ake osokoneza bongo amazindikira kuti ntchito yake imabisala kutentha ndi kukonza.
Njira yochepetsera mafutaHpmcikhoza kugawidwa m'madzi ndikuwonongeka koyambirira mu gawo lochepa kwambiri, cleavage yayikulu ndi mawonekedwe ang'onoang'ono a Moleculization mu gawo la kutentha-sing'anga ndi mpweya wa kutentha kutentha kwambiri. Kukhazikika kwake kwamafuta kumakhudzidwa ndi zinthu monga kapangidwe ka mankhwala, malo ozungulira, kutentha ndi chinyezi. Kuzindikira kuwonongeka kwa mafuta a hpmc ndi phindu lalikulu kuti athe kukonza ntchito ndikusintha bata.
Post Nthawi: Mar-28-2025