01. Taw qhia ntawm cellulose
Cellulose yog macromolecular polysaccharide tsim los ntawm cov piam thaj. Insoluble hauv dej thiab dav dav cov kuab tshuaj organic. Nws yog lub ntsiab tivthaiv ntawm cov nroj tsuag xovtooj phab ntsa, thiab nws kuj yog qhov feem ntau faib thiab feem ntau muaj polysaccharide hauv qhov xwm.
Cellulose yog cov kev pab ntau tshaj plaws txuas ntxiv rau hauv ntiaj teb, thiab nws kuj yog lub ntuj polymer nrog cov tsub zuj zuj. Nws muaj qhov zoo ntawm kev ua dua tshiab, ua kom tiav biodegradable, thiab zoo biocompatibility.
02. Vim li cas rau hloov cellulose
Cellulose maculomolecules muaj ntau pab pawg. Vim yog cov nyhuv ntawm cov kab mob hydrogen, lub zog ntawm macromolecules yog tus loj, uas yuav ua rau lub suab loj me me enthalpy △ h; Ntawm qhov tod tes, muaj cov nplhaib hauv cellulose macromolecules. Zoo li cov qauv, cov rigidity ntawm cov molecular saw loj dua, uas yuav ua rau lub zog me me hloov ΔS. Ob qho laj thawj no ua rau qhov ntsuas kub ntawm molten cellulose (= △ h / △ s) yuav dhau los ua siab dua, thiab qhov kev txiav txim siab ntawm cellulose yog tsawg. Yog li ntawd, thaum lub cellulose yog rhuab rau qee qhov kev tshwm sim uas lub cellulosed ua ntej nws pib ua ntej melting lub txheej txheem ntawm thawj melting thiab tom qab ntawd molding.
03. Tseem ceeb ntawm cellulose hloov kho
Nrog cov chav tsev kawm tiav ntawm cov pob txha pob zeb thiab cov khoom siv hluav taws xob uas muaj zog ntxiv los ua ib qho ntawm cov kub uas tib neeg mob siab rau. Cellulose yog cov muaj ntau ntau dua tshiab uas tau txuas dua tshiab hauv qhov xwm. Nws muaj cov khoom tau zoo heev xws li cov tshuaj tua huab cua zoo, cov tshuaj tua huab, hnav zoo, xis ua, thiab kev ua haujlwm yooj yim, thiab ua kom yooj yim. Nws muaj cov yam ntxwv uas ua rau cov tshuaj lom neeg. Cov.
Cellulose molecules muaj ntau cov pab pawg hydroxyl, uas yog ib pawg hydroxel thiab decomple hydraisen bond, thiab decomple hydrogen bonds, thiab decomple ntawm kub tsis yaj. Txawm li cas los xij, cellulose muaj zoo reactivity, thiab nws cov tshuaj hydrogen yuav raug rhuav tshem los ntawm kev hloov tshuaj lom neeg lossis kev tsim cov tshuaj tiv thaiv, uas tuaj yeem txo qis lub poelting. Raws li ntau yam ntawm cov khoom lag luam, nws yog dav siv nyob rau hauv textiles, membrane sib cais, yas, yas, luam yeeb thiab txheej.
04. Cellulose Ethetification Hloov Kho
Cellulose ether yog ib hom ntawm cellulose derivative tau los ntawm Ethegation hloov kho ntawm cellulose. Nws yog dav siv vim nws qhov zoo heev thickening, raug tshem tawm, kev sau yeeb yaj kiab, noo noo kom ceev, thiab cov nplaum nplaum. Siv nyob rau hauv cov zaub mov, tshuaj, ntawv ua, pleev xim, khoom siv hauv tsev, thiab lwm yam.
Ethetification ntawm cellulose yog cov txheej txheem ntawm cov tshuaj tiv thaiv ntawm cov pab pawg ntawm cellulose molecular nrog alklating cov neeg sawv cev hauv qab cov xwm txheej alkaline. Kev noj ntawm cov pawg hydroxyl txo cov lej ntawm cov khoom siv hydogen ntawm cov ntaub ntawv, thiab tib lub sijhawm txo cov lus melting ntawm cellulose.
Piv txwv ntawm cov kev cuam tshuam ntawm Kev Hloov Chaw Nruab Nrab ntawm lwm lub zog ntawm cellulose:
Siv cov ntaub ntawv paj rwb, cov kws tshawb fawb tau siv ib-theem ethermosyloyl reflex thiab ntsev tsis kam los ntawm kev tiv thaiv zoo thiab etherification kev tiv thaiv. Siv ib-kauj ruam etherification txheej txheem, cov tsim tawm carboxymethyl hydropropyl cellulose muaj ntsev zoo, kua qaub tsis kam thiab solubility. Los ntawm kev hloov cov txheeb ze ntawm propylene oxide thiab chloroacetic acid, cov khoom lag luam nrog cov ntsiab lus sib txawv tuaj yeem npaj tau. Cov txiaj ntsig kev sim ua qhia tau tias cov carboxymethyl hydrodrose kev ua los ntawm ib-qib kuab tshuaj thiab cov ntsev tsis tshua muaj thiab cov kua qaub zoo.
05. Nej xav txog cellulose etherification hloov kho
Cellulose yog cov khoom siv tshuaj lom neeg tseem ceeb thiab cov khoom siv tshuaj lom neeg muaj cov khoom siv tau, ntsuab thiab ib puag ncig phooj ywg, thiab txuas ntxiv mus ntxiv. Lub derivatives ntawm cellulose kev hloov kho tshiab muaj kev ua tau zoo, ntau yam kev siv thiab kev xav tau ntawm kev lag luam hauv tebchaws kom muaj ntau yam. Thiab cov kev xav tau ntawm kev txhim kho kev sib raug zoo, nrog kev ua haujlwm txuas ntxiv thiab cov khoom siv hluavtaws hauv lub neej yav tom ntej, yog tias siv tau ntau dua, lawv yuav muaj ntau txoj kev siv dav dav Cov. Tus nqi
Lub Sijhawm Post: Feb-20-2023