Phase cwj pwm thiab fibril tsim nyob rau hauv aqueous cellulose ethers

Kev coj tus cwj pwm theem thiab fibril tsim hauv aqueouscellulose ethersyog complex phenomena cuam tshuam los ntawm cov qauv tshuaj ntawm cov cellulose ethers, lawv concentration, kub, thiab muaj lwm yam additives. Cellulose ethers, xws li Hydroxypropyl Methylcellulose (HPMC) thiab Carboxymethyl Cellulose (CMC), paub txog lawv lub peev xwm los tsim cov gels thiab nthuav tawm cov theem kev hloov pauv. Ntawm no yog ib lub ntsiab lus dav dav:

Theem cwj pwm:

1. Kev hloov pauv ntawm Sol-Gel:
   • Aqueous kev daws teeb meem ntawm cellulose ethers feem ntau raug hloov pauv sol-gel raws li qhov concentration nce.
   • Nyob rau hauv qis concentrations, cov tshuaj coj zoo li cov kua (sol), thaum nyob rau hauv ntau dua concentrations, nws tsim ib tug zoo li gel qauv.
2. Critical Gelation Concentration (CGC):
   • CGC yog qhov concentration ntawm qhov kev hloov ntawm kev daws mus rau gel tshwm sim.
   • Cov xwm txheej cuam tshuam rau CGC suav nrog qib kev hloov pauv ntawm cellulose ether, qhov kub thiab txias, thiab muaj cov ntsev lossis lwm yam khoom ntxiv.
3. Kub Dependence:
   • Gelation feem ntau nyob ntawm qhov kub thiab txias, nrog qee cov cellulose ethers nthuav tawm cov gelation ntawm qhov kub siab dua.
   • Qhov kub rhiab heev no yog siv rau hauv cov ntawv thov xws li kev tswj cov tshuaj tso tawm thiab kev ua zaub mov.

Fibril Formation:

1. Micellar Aggregation:
   • Ntawm qee qhov concentrations, cellulose ethers tuaj yeem tsim micelles lossis aggregates hauv kev daws.
   • Kev sib sau ua ke yog tsav los ntawm kev sib cuam tshuam hydrophobic ntawm pawg alkyl lossis hydroxyalkyl qhia thaum lub sijhawm etherification.
2. Fibrillogenesis:
   • Kev hloov pauv los ntawm cov khoom siv polymer soluble mus rau insoluble fibrils suav nrog cov txheej txheem hu ua fibrillogenesis.
   • Fibrils yog tsim los ntawm kev sib cuam tshuam ntawm intermolecular, hydrogen bonding, thiab lub cev entanglement ntawm polymer chains.
3. Kev cuam tshuam ntawm Shear:
   • Daim ntawv thov ntawm shear rog, xws li nplawm lossis sib tov, tuaj yeem txhawb kev tsim cov fibril hauv cellulose ether daws.
   • Shear-induced structures muaj feem xyuam rau hauv cov txheej txheem kev lag luam thiab kev siv.
4. Additives thiab Crosslinking:
   • Ntxiv ntsev los yog lwm yam additives tuaj yeem cuam tshuam rau kev tsim cov txheej txheem fibrillar.
   • Crosslinking agents tuaj yeem siv los ua kom ruaj khov thiab ntxiv dag zog rau fibrils.

Daim ntawv thov:

1. Kev xa tshuaj:
   • Cov gelation thiab fibril tsim cov khoom ntawm cellulose ethers yog siv nyob rau hauv kev tswj cov tshuaj tso tawm formulations.
2. Kev lag luam zaub mov:
   • Cellulose ethers pab txhawb kev ntxhib los mos thiab ruaj khov ntawm cov khoom noj khoom haus los ntawm gelation thiab thickening.
3. Cov Khoom Siv Kho Tus Kheej:
   • Gelation thiab fibril tsim txhim khu kev ua tau zoo ntawm cov khoom xws li tshuaj zawv plaub hau, tshuaj pleev, thiab tshuaj pleev.
4. Khoom siv:
   • Gelation cov khoom yog qhov tseem ceeb hauv kev tsim cov khoom siv xws li pobzeb nplaum thiab mortars.

Nkag siab txog theem tus cwj pwm thiab fibril tsim ntawm cellulose ethers yog qhov tseem ceeb rau kev kho lawv cov khoom rau cov kev siv tshwj xeeb. Cov kws tshawb fawb thiab cov kws tsim qauv ua haujlwm los txhim kho cov khoom no kom txhim kho kev ua haujlwm hauv ntau yam lag luam.