Chinthu chofunika kwambiri cha mankhwala a cellulose ether ndi katundu wake wa rheological. Makhalidwe apadera a rheological a ma cellulose ethers ambiri amawapangitsa kuti azigwiritsidwa ntchito kwambiri m'magawo osiyanasiyana, ndipo kuphunzira za rheological properties kumakhala kopindulitsa pakupanga minda yatsopano yogwiritsira ntchito kapena kukonza magawo ena ogwiritsira ntchito. Li Jing wochokera ku yunivesite ya Shanghai Jiao Tong adachita kafukufuku wokhazikika pazikhalidwe za rheologicalcarboxymethylcellulose (CMC), kuphatikiza chikoka cha magawo a CMC a mamolekyulu (kulemera kwa mamolekyulu ndi kuchuluka kwa kulowetsa), ndende pH, ndi mphamvu ya ionic. Zotsatira zafukufuku zikuwonetsa kuti zero-shear viscosity ya yankho imawonjezeka ndi kuwonjezeka kwa kulemera kwa maselo ndi mlingo wolowa m'malo. Kuwonjezeka kwa kulemera kwa maselo kumatanthauza kukula kwa unyolo wa maselo, ndipo kusakanikirana kosavuta pakati pa ma molekyulu kumawonjezera kukhuthala kwa yankho; kulowetsedwa kwakukulu kumapangitsa mamolekyu kutambasula kwambiri mu yankho. Dziko lilipo, voliyumu ya hydrodynamic ndi yayikulu, ndipo mamasukidwe ake amakhala akulu. Kukhuthala kwa njira yamadzimadzi ya CMC kumawonjezeka ndikuwonjezeka kwa ndende, komwe kumakhala ndi viscoelasticity. Kukhuthala kwa yankho kumachepa ndi pH mtengo, ndipo ikakhala yotsika kuposa mtengo wina, kukhuthala kumawonjezeka pang'ono, ndipo pamapeto pake asidi waulere amapangidwa ndikuwombedwa. CMC ndi polyanionic polima, pamene kuwonjezera monovalent mchere ayoni Na+, K+ chishango, mamasukidwe akayendedwe adzachepa moyenerera. Kuphatikiza kwa divalent cation Caz + kumapangitsa kuti kukhuthala kwa yankho kuchepe koyamba kenako ndikuwonjezeka. Pamene kuchuluka kwa Ca2 + ndipamwamba kuposa stoichiometric point, mamolekyu a CMC amalumikizana ndi Ca2 +, ndipo mawonekedwe apamwamba amakhalapo mu yankho. Liang Yaqin, North University of China, etc. ntchito viscometer njira ndi rotational viscometer njira kuchita kafukufuku wapadera pa katundu rheological wa kuchepetsa ndi anaikira njira za kusinthidwa hydroxyethyl mapadi (CHEC). Zotsatira za kafukufukuyu zidapeza kuti: (1) Cationic hydroxyethyl cellulose imakhala ndi mawonekedwe a polyelectrolyte viscosity m'madzi oyera, ndipo kuchepetsedwa kwa mamachulukidwe kumawonjezeka ndi kuchuluka kwa ndende. The intrinsic viscosity ya cationic hydroxyethyl cellulose yokhala ndi digiri yayikulu yolowa m'malo ndi yayikulu kuposa ya cellulose ya cationic hydroxyethyl yokhala ndi m'malo pang'ono. (2) The njira ya cationic hydroxyethyl mapadi zimasonyeza sanali Newtonian madzimadzi makhalidwe ndi makhalidwe kukameta ubweya: monga njira misa ndende ukuwonjezeka, kukhuthala kwake zikuoneka ukuwonjezeka; mumtundu wina wa mchere wa mchere, CHEC yowonekera kukhuthala Imachepa ndi kuwonjezeka kwa mchere wowonjezera. Pansi pa kumeta ubweya womwewo, kukhuthala kowonekera kwa CHEC mu njira yothetsera ya CaCl2 ndikokwera kwambiri kuposa kwa CHEC mu dongosolo la NaCl.
Ndi kuzama kosalekeza kwa kafukufuku ndi kukula kosalekeza kwa minda yogwiritsira ntchito, katundu wa njira zosakanikirana zopangidwa ndi ma cellulose ethers osiyanasiyana alandiranso chidwi cha anthu. Mwachitsanzo, sodium carboxymethyl cellulose (NACMC) ndi hydroxyethyl cellulose (HEC) amagwiritsidwa ntchito ngati mafuta osasunthika m'minda yamafuta, omwe ali ndi ubwino wa kukana kumeta ubweya wambiri, zopangira zambiri komanso kuwonongeka kwa chilengedwe, koma zotsatira za kuzigwiritsa ntchito zokha sizili zabwino. Ngakhale zakale zili ndi mamasukidwe abwino, zimakhudzidwa mosavuta ndi kutentha kwa nkhokwe ndi mchere; ngakhale yotsirizirayi imakhala ndi kutentha kwabwino komanso kukana mchere, mphamvu yake yowonjezereka ndi yochepa ndipo mlingo wake ndi waukulu. Ofufuzawo adasakaniza mayankho awiriwa ndipo adapeza kuti kukhuthala kwa njira yophatikizika kunakula, kukana kutentha ndi kukana kwa mchere kunasinthidwa pang'ono, ndipo zotsatira zake zidakulitsidwa. Verica Sovilj et al. aphunzira khalidwe rheological ya njira ya osakaniza dongosolo wapangidwa HPMC ndi NACMC ndi anionic surfactant ndi rotational viscometer. The rheological khalidwe la dongosolo zimadalira HPMC-NACMC, HPMC-SDS ndi NACMC- (HPMC- SDS) zotsatira zosiyana zinachitika pakati.
The rheological zimatha ma cellulose ether njira zimakhudzidwanso ndi zinthu zosiyanasiyana, monga zowonjezera, mphamvu zamakina akunja ndi kutentha. Tomoaki Hino et al. anaphunzira zotsatira za kuwonjezera kwa chikonga pa rheological properties za hydroxypropyl methylcellulose. Pa 25C ndi ndende yotsika kuposa 3%, HPMC inawonetsa khalidwe la Newtonian fluid. Pamene chikonga chinawonjezeredwa, kukhuthala kumawonjezeka, zomwe zimasonyeza kuti chikonga chimawonjezera kugwidwa kwa chikonga.Mtengo wa HPMCmamolekyu. Chikonga apa chikuwonetsa mphamvu ya salting yomwe imakweza gel point ndi chifunga cha HPMC. Mphamvu zamakina monga kukameta ubweya wa ubweya kudzakhalanso ndi chikoka pa zinthu za cellulose ether amadzimadzi. Kugwiritsa ntchito rheological turbidimeter ndi yaing'ono ngodya kuwala kubalalika chida, amapezeka kuti theka-kuchepetsa njira, kuwonjezera mlingo kukameta ubweya, chifukwa kukameta ubweya kusanganikirana, kusintha kutentha kwa mfundo chifunga adzawonjezeka.
Nthawi yotumiza: Apr-28-2024