Zida Zapamwamba Zochokera ku Cellulose Ether

Ndondomeko ndi ntchito ya carboxymethyl cellulose yolumikizidwa ndi N, N-methylenebisacrylamide pokonzekera utomoni wapamwamba kwambiri adaphunziridwa, ndipo ndende ya alkali, kuchuluka kwa ogwiritsira ntchito mtanda, alkali etherification, ndi zosungunulira zinakambidwa. Zotsatira za mlingo pamayamwidwe amadzi a mankhwalawa. Dongosolo la adsorption la utomoni wotengera madzi m'madzi umafotokozedwa. Kafukufuku wasonyeza kuti mtengo wosungira madzi (WRV) wa mankhwalawa umafika 114ml/g.

Mawu ofunikira:cellulose ether; methylenebisacrylamide; kukonzekera

1,Mawu Oyamba

Superabsorbent resin ndi zinthu za polima zomwe zimakhala ndi magulu amphamvu a hydrophilic komanso kuphatikizika kwina. Zida zomwe zimayamwa madzi monga mapepala, thonje, ndi hemp zimakhala ndi madzi otsika komanso osasunga madzi bwino, pomwe ma resin omwe amamwa kwambiri amatha kuyamwa madzi kuwirikiza kulemera kwawo, ndipo gel osakaniza atamwa madzi sataya madzi ngakhale. ndi kupanikizika pang'ono. Mphamvu yabwino yosungira madzi. Sisungunuka m'madzi kapena mu zosungunulira za organic.

Pali magulu ambiri a hydroxyl, magulu a carboxyl ndi ayoni a sodium hydrate pamamolekyu azinthu zoyamwa kwambiri zopangidwa ndi cellulose. Pambuyo poyamwa madzi, madziwo amazunguliridwa ndi hydrophilic macromolecular network ndipo akhoza kusungidwa pansi pa mphamvu yakunja. Madzi akamanyowetsa utomoni wa adsorption, wosanjikiza wa semi-permeable nembanemba amapangidwa pakati pa utomoni ndi madzi. Chifukwa cha kuchuluka kwa ma ion mafoni (Na+) mu utomoni womwe umamwa madzi, malinga ndi Donnan.'s equilibrium mfundo, kusiyana kwa ndende iyi ya ion kungayambitse kupanikizika kwa osmotic. Osauka, kupanga wonyowa ndi kutupa ofooka mphamvu, madzi akudutsa wosanjikiza theka-permeable nembanemba ndi Chili ndi magulu hydrophilic ndi ayoni pa macromolecules wa superabsorbent utomoni, kuchepetsa ndende ya ayoni mafoni, potero kusonyeza mkulu mayamwidwe madzi ndi kutupa. Njira yotsatsira iyi imapitilira mpaka kusiyana kwa kuthamanga kwa osmotic komwe kumachitika chifukwa cha kusiyana kwa ma ion a mafoni ndikofanana ndi kukana kukulitsa komwe kumachitika chifukwa cha mphamvu yolumikizana ya netiweki ya ma cell a resin ya polima. Ubwino wa superabsorbent resin wokonzedwa kuchokera ku cellulose ndi: kuchuluka kwa mayamwidwe amadzi, kuthamanga kwa mayamwidwe amadzi mwachangu, kukana madzi amchere abwino, osakhala ndi poizoni, osavuta kusintha pH mtengo, amatha kunyonyotsoka m'chilengedwe, komanso mtengo wotsika, chifukwa chake uli ndi mawonekedwe ambiri. osiyanasiyana ntchito. Itha kugwiritsidwa ntchito ngati chotchinga madzi, chowongolera nthaka, komanso chosungira madzi m'makampani ndi ulimi. Kuphatikiza apo, ili ndi chitukuko chabwino komanso chiyembekezo chogwiritsa ntchito paumoyo, chakudya, microbiology, ndi mankhwala.

2. Gawo loyesera

2.1 Mfundo yoyesera

Kukonzekera kwa thonje utomoni superabsorbent utomoni makamaka kupanga mtanda cholumikizira dongosolo ndi otsika mlingo m'malo pa CHIKWANGWANI khungu. Kuphatikizana ndi mankhwala omwe nthawi zambiri amakhala ndi magulu awiri kapena angapo ogwira ntchito. Magulu ogwira ntchito amatha kugwirizanitsa ndi vinyl, hydroxyl, carboxyl, amide, asidi kolorayidi, oxirane, nitrile, etc. The mayamwidwe chiŵerengero cha madzi mayamwidwe utomoni superabsorbent anakonza ndi osiyana mtanda-kugwirizana wothandizira ndi osiyana. Pakuyesaku, N, N-methylenebisacrylamide imagwiritsidwa ntchito ngati njira yolumikizirana, kuphatikiza izi:

(1) Ma cellulose (Rcell) amakhudzidwa ndi njira ya alkaline kupanga alkali cellulose, ndipo alkalization reaction of cellulose ndikuchita mwachangu exothermic. Kutsitsa kutentha kumathandizira kupanga ulusi wa alkali ndipo kumatha kulepheretsa hydrolysis yawo. Kuonjezera zakumwa zoledzeretsa kungapangitse kusokonezeka kwa cellulose, komwe kumapindulitsa ku alkalization ndi etherification wotsatira.

RcellOH+NaOH→RcellONA+H2O

(2) Alkali cellulose ndi monochloroacetic acid amapanga sodium carboxymethyl cellulose, ndipo etherification reaction ndi ya nucleophilic substitution reaction:

RcellONA+ClCH2COONA→RcellOCH2COONA+NaCl

(3) N, N-methylenebisacrylamide yolumikizidwa kuti ipeze utomoni woyamwa kwambiri. Chifukwa pakadali magulu ambiri a hydroxyl pamamolekyu a carboxymethyl fiber, ionization ya gulu la hydroxyl la cellulose ndi ionization ya acryloyl bond pagulu la molekyulu ya N, N-methylenebisacrylamide imatha kuyambitsa alkali catalysis, ndiyeno Cross-kulumikizana pakati pa mapadi unyolo maselo kumachitika kudzera Michael condensation, ndipo nthawi yomweyo amadutsa pulotoni kuwombola madzi kukhala madzi-insoluble mapadi superabsorbent utomoni.

2.2 Zipangizo ndi zida

Zopangira: thonje loyamwa (lodulidwa mu linter), sodium hydroxide, monochloroacetic acid, N, N-methylenebisacrylamide, ethanol mtheradi, acetone.

Zida: botolo la makosi atatu, kusonkhezera kwamagetsi, reflux condenser, botolo loyamwitsa, Buchner funnel, uvuni wowumitsa vacuum, pampu yozungulira ya vacuum yamadzi.

2.3 Njira yokonzekera

2.3.1 Alkalilization

Onjezani 1 g wa thonje woyamwa mu botolo la makosi atatu, kenaka onjezerani madzi enaake a sodium hydroxide solution ndi ethanol wathunthu, sungani kutentha kosachepera kutentha, ndikugwedezani kwakanthawi.

2.3.2 Etherification

Onjezani kuchuluka kwa chloroacetic acid ndikugwedeza kwa 1h.

2.3.2 Kulumikizana

M'magawo omaliza a etherification, N,N-methylenebisacrylamide idawonjezedwa molingana kuti ilumikizane, ndikugwedezeka kutentha kwa maola awiri.

2.3.4 Pambuyo pokonza

Gwiritsani ntchito glacial acetic acid kuti musinthe pH kukhala 7, yambani mcherewo ndi ethanol, yambani madzi ndi acetone, fyuluta ndi kuyamwa, ndi vacuum youma kwa maola 4 (pafupifupi 60).°C, vacuum degree 8.8kPa) kuti mupeze chopangidwa ndi thonje loyera la thonje.

2.4 Kuyesa kupenda

Kuchuluka kwa madzi (WRV) kumatsimikiziridwa ndi sieving, ndiko kuti, 1g ya mankhwala (G) amawonjezeredwa ku beaker yomwe ili ndi 100ml ya madzi osungunuka (V1), oviikidwa kwa maola 24, amasefedwera pawindo lazitsulo zosapanga dzimbiri 200. , ndipo madzi pansi pa chinsalu amasonkhanitsidwa (V2). Njira yowerengera ili motere: WRV=(V1-V2)/G.

3. Zotsatira ndi zokambirana

3.1 Kusankhidwa kwa zinthu za alkalization reaction

Popanga ma cellulose a alkali pogwiritsa ntchito ulusi wa thonje ndi njira ya alkaline, momwe zinthu zimagwirira ntchito zimakhudza kwambiri momwe zinthu zimagwirira ntchito. Pali zinthu zambiri zomwe zimachitika mu alkalization. Kuti muwone mosavuta, njira yoyesera ya orthogonal imatengedwa.

Zina: Zosungunulira ndi 20ml za ethanol mtheradi, chiŵerengero cha alkali ndi etherifying agent (mol/md) ndi 3:1, ndi crosslinking agent ndi 0.05g.

Zotsatira zoyesera zikuwonetsa kuti: ubale woyamba ndi wachiwiri: C> A> B, chiŵerengero chabwino kwambiri: A3B3C3. Kuchuluka kwa lye ndiye chinthu chofunikira kwambiri pakuchita kwa alkalization. Kuchuluka kwa lye kumathandizira kupanga alkali cellulose. Komabe, tisaiwale kuti apamwamba ndende ya lye, ndi waukulu mchere zili okonzeka superabsorbent utomoni. Choncho, potsuka mcherewo ndi ethanol, muzitsuka kangapo kuti mutsimikize kuti mchere womwe uli mu mankhwalawo umachotsedwa, kuti musawononge mphamvu ya madzi a mankhwalawa.

3.2 Mphamvu ya crosslinking wothandizira mlingo pa mankhwala WRV

Mikhalidwe yoyesera ndi: 20ml ya ethanol mtheradi, 2.3:1 chiŵerengero cha alkali ndi etherification agent, 20ml ya lye, ndi 90min ya alkalization.

Zotsatira zake zidawonetsa kuti kuchuluka kwa othandizira olumikizana nawo kumakhudza digiri yolumikizirana ya CMC-Na. Kuphatikizika kwakukulu kumabweretsa dongosolo lolimba la maukonde mu malo ogulitsa, omwe amadziwika ndi kuchuluka kwa mayamwidwe amadzi otsika komanso kusakhazikika bwino pambuyo pa kuyamwa kwamadzi; pamene kuchuluka kwa njira yolumikizira mtanda ndi yaying'ono, kulumikizako sikukwanira, ndipo pali zinthu zosungunuka madzi, zomwe zimakhudzanso kuchuluka kwa madzi. Pamene kuchuluka kwa njira yolumikizirana ndi yochepera 0.06g, kuchuluka kwa mayamwidwe amadzi kumawonjezeka ndikuwonjezeka kwa kuchuluka kwa othandizira olumikizirana, pomwe kuchuluka kwa othandizira olumikizirana kukupitilira 0.06g, kuchuluka kwa mayamwidwe amadzi kumachepa. ndi kuchuluka kwa crosslinking agent. Choncho, mlingo wa crosslinking wothandizira ndi pafupifupi 6% ya thonje ulusi misa.

3.3 Mmene zinthu etherification pa mankhwala WRV

Mikhalidwe yoyesera ndi: ndende ya alkali 40%; alkali buku 20ml; ethanol mtheradi 20ml; Mlingo wolumikizira wolumikizana ndi 0.06g; alkalization 90min.

Kuchokera ku mankhwala opangidwa ndi mankhwala, chiŵerengero cha alkali-ether (NaOH:CICH2-COOH) chiyenera kukhala 2: 1, koma kuchuluka kwenikweni kwa alkali komwe kumagwiritsidwa ntchito ndi kwakukulu kuposa chiŵerengero ichi, chifukwa chiwerengero china cha alkali chaulere chiyenera kutsimikiziridwa mu machitidwe. , chifukwa: zina A mkulu ndende ya ufulu m'munsi ndi yabwino kuti akamaliza anachita alkalization; njira yolumikizirana iyenera kuchitika pansi pamikhalidwe yamchere; mbali zina zimadya zamchere. Komabe, ngati kuchuluka kwa alkali kuwonjezeredwa kwambiri, ulusi wa alkali udzawonongeka kwambiri, ndipo nthawi yomweyo, mphamvu ya etherification wothandizira idzachepetsedwa. Mayesero amasonyeza kuti chiŵerengero cha alkali ndi ether ndi pafupifupi 2.5:1.

3.4 Mphamvu ya zosungunulira ndalama

Mikhalidwe yoyesera ndi: ndende ya alkali 40%; Mlingo wa alkali 20 ml; chiŵerengero cha alkali-etere 2.5:1; cross-linking wothandizira mlingo 0.06g, alkalization 90min.

The zosungunulira anhydrous Mowa amasewera udindo dispersing, homogenizing ndi kukhalabe slurry boma dongosolo, amene n'kopindulitsa kumwazikana ndi kusamutsa kutentha anamasulidwa pa mapangidwe alkali mapadi, ndipo akhoza kuchepetsa hydrolysis anachita za cellulose zamchere, potero kupeza yunifolomu. cellulose. Komabe, ngati kuchuluka kwa mowa wowonjezera ndi wochuluka, alkali ndi sodium monochloroacetate zidzasungunuka mmenemo, kuchuluka kwa reactants kudzachepa, momwe zimakhalira zidzachepa, ndipo zidzakhalanso ndi zotsatira zovuta pa crosslinking yotsatira. Pamene kuchuluka kwa ethanol mtheradi ndi 20ml, mtengo wa WRV ndi waukulu.

Mwachidule, zinthu zabwino kwambiri pokonzekera superabsorbent utomoni kuchokera absorbent thonje alkalized ndi etherified carboxymethyl mapadi mtanda cholumikizidwa ndi N, N-methylenebisacrylamide ndi: zamchere ndende 40%, zosungunulira-free 20ml madzi ndi Mowa, chiŵerengero cha alkali ndi etha. ndi 2.5:1, ndipo mlingo wa crosslinking agent ndi 0.06g (6% ya kuchuluka kwa linters thonje).