Yang'anani pa ma cellulose ethers

Kodi ndi zinthu ziti zomwe zimakhudza kasungidwe ka madzi pazinthu za HPMC?

Hydroxypropyl methylcellulose (HPMC, Hydroxypropyl Methylcellulose) ndi yofunika kwambiri ya cellulose ether, yomwe imagwiritsidwa ntchito kwambiri pomanga, mankhwala, chakudya ndi madera ena, ndipo imapezeka makamaka muzomangamanga. Kusungidwa kwa madzi kwa HPMC ndi chimodzi mwazinthu zofunika kwambiri ndipo kumagwira ntchito yofunika kwambiri pazochitika zambiri zogwiritsira ntchito. Zinthu zomwe zimakhudza kusungidwa kwa madzi kwa HPMC zimaphatikizapo kapangidwe ka maselo, kuchuluka kwa m'malo, kulemera kwa maselo, kusungunuka, kutentha kozungulira, zowonjezera, ndi zina zambiri.

1. Mapangidwe a mamolekyu
HPMC ndi chochokera ku cellulose chomwe ma cell ake amakhudza kwambiri kusunga madzi. Maselo a HPMC ali ndi hydrophilic hydroxyl (-OH), lipophilic methyl (-CH₃) ndi hydroxypropyl (-CH₂CHOHCH₃). Kuchuluka ndi kugawa kwa magulu a hydrophilic ndi lipophilic kumakhudza mwachindunji ntchito yosunga madzi ya HPMC.

Udindo wamagulu a hydroxyl: Magulu a Hydroxyl ndi magulu a hydrophilic omwe amatha kupanga ma hydrogen bond ndi mamolekyu amadzi, potero amathandizira kukonza kasungidwe ka madzi a HPMC.
Udindo wa magulu a methyl ndi hydroxypropyl: Maguluwa ndi a hydrophobic ndipo amatha kukhudza kusungunuka ndi kutentha kwa gelation kwa HPMC m'madzi, potero kumakhudza kasungidwe ka madzi.

2. Digiri ya m'malo
Digiri ya m'malo (DS) imatanthawuza kuchuluka kwa magulu a hydroxyl olowetsedwa m'malo mwa ma cellulose. Kwa HPMC, kuchuluka kwa kusintha kwa methoxy (-OCH₃) ndi hydroxypropoxy (-OCH₂CHOHCH₃) nthawi zambiri kumakhudzidwa, ndiko kuti, kuchuluka kwa kusintha kwa methoxy (MS) ndi kuchuluka kwa hydroxypropoxy (HP):

Kulowa m'malo kwapamwamba: Kukwera kwa kuchuluka kwa m'malo, magulu a HPMC amakhala ndi ma hydrophilic, ndipo kunena kuti kusungidwa kwa madzi kudzakhala bwino. Komabe, kulowetsedwa kwakukulu kwambiri kungayambitse kusungunuka kwakukulu, ndipo zotsatira zosunga madzi zimatha kuchepetsedwa.
M'malo otsika: HPMC yokhala ndi m'malo pang'ono imakhala yosasungunuka bwino m'madzi, koma mawonekedwe a netiweki amatha kukhala okhazikika, potero amasunga madzi abwinoko.
Kusintha kuchuluka kwa kulowetsa m'malo mwamitundu ina kumatha kukulitsa kusungidwa kwamadzi kwa HPMC. Madigirii olowa m'malo wamba nthawi zambiri amakhala 19-30% ya methoxy ndi 4-12% ya hydroxypropoxy.

3. Kulemera kwa mamolekyu
Kulemera kwa mamolekyu a HPMC kumakhudza kwambiri kusunga kwake madzi:

Kulemera kwakukulu kwa maselo: HPMC yokhala ndi kulemera kwakukulu kwa maselo imakhala ndi maunyolo aatali a maselo ndipo imapanga mawonekedwe osakanikirana, omwe amatha kukhala ndi madzi ochulukirapo, motero amawongolera kusunga madzi.
Kulemera kwa mamolekyulu otsika: HPMC yokhala ndi mamolekyu otsika imakhala ndi mamolekyu amfupi komanso mphamvu yosungira madzi yocheperako, koma imakhala ndi kusungunuka kwabwino ndipo ndiyoyenera kugwiritsa ntchito zomwe zimafunikira kusungunuka mwachangu.
Nthawi zambiri, kuchuluka kwa zolemetsa za HPMC zomwe zimagwiritsidwa ntchito pomanga zimachokera ku 80,000 mpaka 200,000.

4. Kusungunuka
Kusungunuka kwa HPMC kumakhudza mwachindunji kusunga kwake madzi. Kusungunuka kwabwino kumathandiza HPMC kuti imwazike mokwanira mu masanjidwewo, potero imapanga mawonekedwe osungira madzi. Kusungunuka kumakhudzidwa ndi:

Kutentha kwa kutentha: HPMC imasungunuka pang'onopang'ono m'madzi ozizira, koma imasungunuka mofulumira m'madzi ofunda. Komabe, kutentha kwambiri kumapangitsa kuti HPMC isungunuke kwambiri, zomwe zimakhudza momwe imasungira madzi.
Phindu la pH: HPMC imakhudzidwa ndi mtengo wa pH ndipo imakhala yosungunuka bwino m'malo osalowerera kapena opanda acidic. Itha kutsitsa kapena kuchepetsa kusungunuka pansi pa ma pH apamwamba kwambiri.

5. Kutentha kozungulira
Kutentha kumakhudza kwambiri kusunga madzi kwa HPMC:

Kutentha kochepa: Pa kutentha kochepa, kusungunuka kwa HPMC kumachepa, koma kukhuthala kwake kumakhala kokwera, komwe kungapangitse dongosolo lokhazikika losungira madzi.
Kutentha kwakukulu: Kutentha kwakukulu kumafulumizitsa kusungunuka kwa HPMC, koma kungayambitse kuwonongeka kwa kamangidwe kamene kamasungira madzi ndikusokoneza momwe madzi amasungira. Nthawi zambiri, kusunga bwino madzi kumatha kusungidwa pansi pa 40 ℃.

6. Zowonjezera
HPMC nthawi zambiri amagwiritsidwa ntchito limodzi ndi zina zowonjezera pazogwiritsa ntchito. Zowonjezera izi zitha kukhudza kusungidwa kwa madzi kwa HPMC:

Plasticizers: monga glycerol ndi ethylene glycol, amene angathe kusintha kusinthasintha ndi kusunga madzi a HPMC.
Zodzaza: monga gypsum ndi quartz powder, zidzakhudza kusungidwa kwa madzi kwa HPMC ndikusintha makhalidwe ake obalalika ndi kusungunuka mwa kuyanjana ndi HPMC.

7. Mikhalidwe yofunsira
Kusunga madzi kwa HPMC kudzakhudzidwanso pansi pamikhalidwe yosiyanasiyana yogwiritsira ntchito:

Zomangamanga: monga nthawi yomanga, chinyezi cha chilengedwe, ndi zina zambiri zidzakhudza momwe HPMC imasungira madzi.
Kugwiritsa ntchito: Kuchuluka kwa HPMC kumakhudza mwachindunji kusunga madzi. Nthawi zambiri, HPMC yokhala ndi mlingo wapamwamba imawonetsa bwino kusunga madzi mumatope a simenti ndi zida zina.

Pali zinthu zambiri zomwe zimakhudza kusungidwa kwa madzi kwa HPMC, kuphatikiza kapangidwe kake ka maselo, kuchuluka kwa m'malo, kulemera kwa maselo, kusungunuka, kutentha kozungulira, zowonjezera, ndi mikhalidwe yeniyeni yogwiritsira ntchito. Panthawi yogwiritsira ntchito, posankha mwanzeru ndikusintha zinthuzi, ntchito yosungira madzi ya HPMC ikhoza kukonzedwa kuti ikwaniritse zosowa za madera osiyanasiyana.


Nthawi yotumiza: Jun-24-2024
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