Hydroxyethyl cellulose (HEC) ndi yofunika kusungunuka m'madzi cellulose ether, yomwe imagwiritsidwa ntchito kwambiri popaka, pobowola mafuta, mankhwala ndi zina. Kusungunuka kwake ndi gawo lofunikira lomwe limakhudza kukonza ndi kugwiritsa ntchito kwake. Zomwe zimakhudza malo osungunuka a hydroxyethyl cellulose zitha kugawidwa m'magulu angapo, monga mawonekedwe a maselo, kuchuluka kwa m'malo, kulemera kwa maselo, crystallinity, zonyansa, ndi chilengedwe.
1. Mapangidwe a mamolekyu
Ma cellulose a Hydroxyethyl amapangidwa ndi cellulose pambuyo pa ethoxylation. Mapangidwe ake ofunikira ndikuti maatomu a haidrojeni mu molekyulu ya cellulose amasinthidwa ndi magulu a hydroxyethyl. Malo, chiwerengero ndi dongosolo la hydroxyethyl m'malo zidzakhudza malo ake osungunuka.
Malo olowa m'malo: Chigawo chilichonse cha shuga mu cellulose chimakhala ndi magulu atatu a hydroxyl omwe angasinthidwe. Kulowetsa m'malo osiyanasiyana kudzasintha mawonekedwe a malo a molekyulu, motero zimakhudza malo osungunuka.
Chiwerengero cha zolowa m'malo: Kuwonjezeka kwa kuchuluka kwa zolowa m'malo nthawi zambiri kumachepetsa kulumikizana kwa haidrojeni pakati pa mamolekyu, potero kumachepetsa malo osungunuka.
Dongosolo la makonzedwe olowa m'malo: Zomwe zimagawidwa mwachisawawa komanso zogawidwa pafupipafupi zimakhala ndi zotsatira zosiyana pa kusinthasintha ndi kuyanjana kwa unyolo wa ma molekyulu, potero zimakhudza malo osungunuka.
2. Digiri ya Kusintha (DS)
DS imatanthauza kuchuluka kwa zolowa m'malo mwa hydroxyethyl pagawo lililonse la shuga. Mlingo wolowa m'malo umakhudza kwambiri malo osungunuka, omwe amawonekera makamaka muzinthu izi:
Low DS: Potsika DS, kugwirizana kwa haidrojeni pakati pa mamolekyu a hydroxyethyl cellulose kumakhala kolimba, kumapangitsa kuti mamolekyuwa azikhala omangika kwambiri komanso malo osungunuka akukwera.
High DS: High DS imawonjezera kusinthasintha kwa mamolekyu ndikuchepetsa mphamvu ya hydrogen bonding, kupangitsa mamolekyu kukhala osavuta kutsetsereka komanso malo osungunuka.
3. Kulemera kwa Maselo
Kulemera kwa ma cell kumakhudza mwachindunji malo osungunuka a hydroxyethyl cellulose. Nthawi zambiri, kulemera kwa mamolekyu kukakhala kokulirapo, unyolo wa mamolekyu utalikirapo, mphamvu ya van der Waals imakhala yamphamvu pakati pa mamolekyu, ndipo m’pamenenso imasungunuka. Kuonjezera apo, m'lifupi mwa kugawa kwa kulemera kwa maselo kudzakhudzanso malo osungunuka, ndipo kugawidwa kwakukulu kungayambitse kusungunuka kosagwirizana.
Kulemera kwa mamolekyulu: Unyolo wa mamolekyu ndi wautali, womangiriridwa wina ndi mzake, ndipo malo osungunuka ndi apamwamba.
Kulemera kwa mamolekyu otsika: Unyolo wa maselo ndi wamfupi, mphamvu za intermolecular zimakhala zofooka, ndipo malo osungunuka ndi ochepa.
4. Crystallinity
Hydroxyethyl cellulose ndi polima amorphous, koma ikhoza kukhalabe ndi madera ena a crystalline. Kukhalapo kwa madera a crystalline kumawonjezera malo osungunuka chifukwa mawonekedwe a crystalline ndi okhazikika ndipo amafunikira mphamvu zambiri kuti athyole zinthu zomwe zalamulidwa. Mlingo wa hydroxyethylation ndi zochitika ndondomeko zimakhudza crystallinity ake.
Kuwala kwambiri: mawonekedwe olimba, malo osungunuka kwambiri.
Low crystallinity: mawonekedwe omasuka, malo osungunuka otsika.
5. Zonyansa
Panthawi yopanga ma cellulose a hydroxyethyl, zida zina zosagwiritsidwa ntchito, zopangira kapena zopangira zimatha kukhala. Kukhalapo kwa zonyansazi kungasinthe mphamvu za intermolecular, motero zimakhudza malo osungunuka. Mwachitsanzo:
Chothandizira chotsalira: zovuta zimatha kupangidwa, kusintha malo osungunuka.
Zomwe zimapangidwanso: Kukhalapo kwa zinthu zosiyanasiyana kumasintha kuyanjana kwadongosolo ndikusokoneza malo osungunuka.
6. Mikhalidwe ya chilengedwe
Zinthu zachilengedwe monga kutentha ndi chinyezi zidzakhudzanso malo osungunuka a hydroxyethyl cellulose. Pansi pa chinyezi chambiri, hydroxyethyl cellulose imapangidwa ndi plasticization pambuyo poyamwa madzi, zomwe zidzafooketsa mphamvu za intermolecular ndikuchepetsa kusungunuka.
Kutentha kwakukulu: Kungayambitse kuwonongeka kwa zinthu ndi kukulitsa malo osungunuka.
Chinyezi chachikulu: Unyolo wa mamolekyu umakhala wosinthika kwambiri ukatha kuyamwa madzi, ndipo malo osungunuka amachepa.
7. Processing Technology
Kutentha, kumeta ubweya wa ubweya, kuyanika zinthu, ndi zina zotero panthawi yokonza zidzakhudza malo osungunuka a mankhwala omaliza. Zosiyanasiyana pokonza zinthu zimabweretsa kusiyanasiyana kwa ma cell ndi crystallinity, zomwe zimakhudzanso malo osungunuka.
Kutentha kwa processing: Kutentha kwapamwamba kwambiri kungayambitse kuwonongeka pang'ono kapena kugwirizanitsa, kusintha malo osungunuka.
Kuyanika zinthu: Kuyanika mwachangu ndi kuyanika pang'onopang'ono kumakhala ndi zotsatira zosiyana pa dongosolo la mamolekyu, ndipo malo osungunuka adzakhalanso osiyana.
Mwachidule, zinthu zomwe zimakhudza kusungunuka kwa hydroxyethyl cellulose zimaphatikizapo kapangidwe ka maselo, kuchuluka kwa m'malo, kulemera kwa maselo, crystallinity, zonyansa, chilengedwe komanso ukadaulo wopanga. Pakugwiritsa ntchito ndi kukonza, kuwongolera koyenera kwa zinthu izi kumatha kukulitsa magwiridwe antchito a hydroxyethyl cellulose ndikupangitsa kuti ikwaniritse zofunikira zosiyanasiyana. Popanga, kusintha kwa sayansi kwa magawowa sikungangowonjezera kusungunuka kwa chinthucho, komanso kumapangitsanso kukhazikika ndi khalidwe la mankhwala.
Nthawi yotumiza: Jul-10-2024