Polyanionic cellulose (PAC) yog ib qho kev hloov kho cellulose derivative uas tau siv dav hauv ntau daim ntawv thov kev lag luam. Qhov no ntau yam polymer yog muab los ntawm cellulose, ib tug natural polysaccharide pom nyob rau hauv cov nroj tsuag cell phab ntsa. Kev hloov kho suav nrog kev qhia txog cov pab pawg anionic ntawm cov pob txha cellulose, yog li ua kom cov dej solubility thiab txhim kho rheological zog. Cov txiaj ntsig PAC muaj cov khoom tshwj xeeb uas ua rau nws muaj txiaj ntsig hauv kev lag luam roj thiab roj, khoom noj khoom haus, tshuaj, thiab lwm yam.
Cellulose yog ib tug linear polymer tsim los ntawm rov qab cov piam thaj txuas los ntawm β-1,4-glycosidic bonds. Nws yog nplua nuj nyob rau hauv cov xwm thiab yog ib feem ntawm cov nroj tsuag cell phab ntsa. Txawm li cas los xij, ntuj cellulose muaj kev txwv tsis pub solubility hauv dej vim nws muaj zog intermolecular hydrogen bonds. Txhawm rau kov yeej qhov kev txwv no, polyanionic cellulose tau tsim los ntawm kev hloov kho tshuaj lom neeg.
Ib txoj hauv kev rau PAC ntau lawm suav nrog etherification lossis esterification cov tshuaj tiv thaiv. Thaum cov txheej txheem no, pawg anionic, xws li carboxylate lossis sulfonate pawg, tau nkag mus rau hauv cov saw cellulose. Qhov no muab cov polymer tsis zoo, ua rau nws cov dej-soluble thiab muab nws cov khoom tshwj xeeb. Lub degree ntawm kev hloov pauv lossis tus naj npawb ntawm anionic pawg hauv ib chav tsev qabzib tuaj yeem hloov kho kom haum rau cov khoom ntawm PAC kom ua tau raws li cov ntawv thov tshwj xeeb.
Ib qho ntawm cov kev siv tseem ceeb ntawm PAC yog nyob rau hauv kev lag luam roj thiab roj, qhov twg nws yog siv los ua ib qho tseem ceeb additive nyob rau hauv drilling kua. Drilling kua, tseem hu ua av nkos, ua si ntau yam ntawm lub luag haujlwm tseem ceeb hauv cov txheej txheem drilling ntawm cov roj thiab cov qhov dej, suav nrog kev ua kom txias rau cov laum me ntsis, thauj cov txiav mus rau saum npoo, thiab tswj kev ruaj ntseg zoo. Ntxiv PAC rau cov dej drilling tswj nws cov khoom rheological, xws li viscosity thiab kua poob. Nws ua raws li tackifier, tiv thaiv cov khib nyiab los ntawm kev nyob thiab ua kom muaj kev cuam tshuam zoo hauv cov kua dej.
Cov khoom rheological ntawm PAC tuaj yeem raug kho kom zoo kom ua tiav qhov xav tau sib npaug ntawm viscosity thiab kua tsis tswj. Qhov no yog ib qho tseem ceeb tshwj xeeb rau kev ua haujlwm drilling nyob rau hauv cov xwm txheej sib txawv, xws li kev sib txawv thiab qhov kub thiab txias. PAC cov dej solubility kuj ua rau nws yooj yim rau kev sib xyaw nrog cov kua dej drilling, thiab nws txoj kev ruaj ntseg thoob plaws ntau yam ntawm pH ntxiv txhim kho nws cov txiaj ntsig hauv thaj chaw.
Ntxiv rau nws lub luag haujlwm hauv cov dej drilling, PAC tau siv ntau yam kev siv. Hauv kev lag luam khoom noj khoom haus, nws yog siv los ua cov thickener thiab stabilizer hauv cov khoom xws li cov khaub ncaws hnav khaub ncaws, cov kua ntses thiab cov khoom siv mis nyuj. Nws lub peev xwm los txhim kho viscosity thiab tswj kev ntxhib los mos ua rau nws muaj txiaj ntsig hauv cov qauv uas cov khoom no tseem ceeb heev.
Kev lag luam kws tshuaj kuj tseem siv PACs ua cov khoom ntxiv hauv cov tshuaj formulations. Nws tuaj yeem suav nrog hauv cov ntsiav tshuaj coatings thiab tswj-tso formulations los hloov kho cov tshuaj tso tawm. Biocompatibility thiab toxicity tsawg ntawm PAC pab txhawb rau nws qhov kev lees paub hauv kev siv tshuaj.
Tsis tas li ntawd, PAC tau pom cov ntawv thov hauv cov txheej txheem kho dej. Nws qhov xwm txheej anionic tso cai rau nws cuam tshuam nrog cov khoom muaj txiaj ntsig zoo, pab tshem tawm impurities ntawm dej. Nyob rau hauv cov ntaub ntawv no, nws ua raws li ib tug flocculant los yog coagulant, txhawb lub aggregation ntawm hais kom lawv yooj yim tshem tawm los ntawm sedimentation los yog pom.
Txawm hais tias nws siv dav heev, cov teeb meem ib puag ncig thiab kev ruaj ntseg cuam tshuam nrog PAC tsim thiab pov tseg yuav tsum raug txiav txim siab. Cov kws tshawb fawb thiab kev lag luam tseem niaj hnub tshawb nrhiav ntsuab chemistry thiab lwm qhov chaw ntawm cellulose los daws cov teeb meem no.
Polyanionic cellulose yog ib qho piv txwv zoo ntawm yuav ua li cas hloov tshuaj lom neeg tuaj yeem hloov cov polymers ntuj rau hauv cov ntaub ntawv siv ntau yam nrog ntau yam kev siv. Nws lub luag haujlwm hauv kev lag luam xws li roj thiab roj, khoom noj khoom haus thiab tshuaj qhia txog nws txoj kev siv ntau yam thiab qhov tseem ceeb ntawm cov cellulose derivatives hauv cov txheej txheem tsim khoom niaj hnub no. Raws li kev siv thev naus laus zis thiab kev xav tau kev daws teeb meem loj zuj zus tuaj, kev tshawb nrhiav rau ib puag ncig tus phooj ywg txoj hauv kev ntawm PAC ntau lawm thiab nws cov ntawv thov yuav txuas ntxiv txhim kho.
Post lub sij hawm: Dec-19-2023