Super Absorbent Material kubva kuCellulose Ether

Maitiro uye kuita kwechigadzirwa che carboxymethyl cellulose cross-linked by N, N-methylenebisacrylamide kugadzirira superabsorbent resin zvakadzidzwa, uye kusungirirwa kwealkali, kuwanda kwe-cross-linking agent, alkali etherification, uye solvent zvakakurukurwa. Mhedzisiro yedosage pakubata kwemvura kuita kwechigadzirwa. Iyo adsorption mechanism yemvura-inopinza resin kumvura inotsanangurwa. Zvidzidzo zvakaratidza kuti kukosha kwekuchengetedza mvura (WRV) kwechigadzirwa ichi kunosvika 114ml/g.

Mazwi akakosha:cellulose ether; methylenebisacrylamide; kugadzirira

1,Nhanganyaya

Superabsorbent resin ndeye polymer zvinhu zvine akasimba hydrophilic mapoka uye imwe dhigirii yekuyambuka. Zvakajairwa-kunwa mvura zvinhu zvakaita sebepa, donje, uye hemp zvine mwero wakaderera wekutora mvura uye husina kunaka hwekuchengeta mvura, nepo maresheni akanyanya-absorbent anogona kutora mvura kakawanda kakapetwa huremu hwawo, uye gel rinoumbwa mushure mekutora mvura harizopedzi mvura kunyangwe. nekumanikidza kushoma. Yakanakisa kuchengetedza mvura. Hainyungudike mumvura kana muorganic solvents.

Kune huwandu hukuru hwemapoka e-hydroxyl, mapoka e-carboxyl uye sodium hydrate ions pane molecular cheni yeakanyanya kunyudza zvinhu zvakagadzirwa neselulosi. Mushure mekutora mvura, mvura yakakomberedzwa ne hydrophilic macromolecular network uye inogona kuchengetwa pasi pekumanikidzwa kwekunze. Kana mvura ikanyorovesa adsorption resin, mutsetse we semi-permeable membrane inoumbwa pakati pe resin nemvura. Nekuda kwekuwanda kweiyo nharembozha (Na+) mumvura inonyura resin, maererano naDonnan.'s equilibrium musimboti, iyi ion concentration musiyano inogona kukonzera osmotic pressure. Murombo, achigadzira inonyorovesa uye kuzvimba simba risina simba, mvura inopfuura nepakati peiyo semi-permeable membrane uye inosanganiswa nemapoka ehydrophilic uye ions pane macromolecules e superabsorbent resin, ichideredza kuwanda kweiyo nharembozha, zvichiratidza kunyura kwemvura uye kuzvimba. Iyi adsorption process inoenderera mberi kusvika iyo osmotic pressure mutsauko unokonzerwa nemusiyano mukusangana kweiyo mobile ions yakaenzana nekupokana nekuwedzera kuwedzera kunokonzerwa nekubatana kwesimba remamorekuru network yepolymer resin. Zvakanakira superabsorbent resin yakagadzirwa kubva ku cellulose ndeiyi: mwero wekunyudzwa kwemvura, kukurumidza kunyudzwa kwemvura, kunaka kwemvura yemunyu inodzivirira, isina chepfu, iri nyore kugadzirisa pH kukosha, inogona kuderedzwa muzvisikwa, uye yakaderera mutengo, saka ine yakafara. zvakasiyana-siyana zvekushandisa. Inogona kushandiswa semvura inovharira mumiriri, ivhu conditioner, uye mvura inochengetedza mumiriri muindasitiri nekurima. Pamusoro pezvo, ine budiriro yakanaka uye tarisiro yekushandisa mune hutano, chikafu, microbiology, uye mushonga.

2. Chikamu chekuedza

2.1 Chiyedzo musimboti

Kugadzirira kwekotoni fiber superabsorbent resin inonyanya kuumba chimiro chemuchinjikwa-chinopindirana nechepasi chekugadzirisa pane fiber ganda. Muchinjikwa-kubatanidza kune makomisheni ayo anowanzo aine maviri kana anopfuura anochinja anoshanda mapoka. Mapoka anoshanda anokwanisa kuyambuka-kubatanidza anosanganisira vinyl, hydroxyl, carboxyl, amide, acid chloride, oxirane, nitrile, etc. Mvura yekunyura reshiyo ye superabsorbent resins yakagadzirwa neyakasiyana-siyana-inobatanidza vamiririri yakasiyana. Muchiyedzo ichi, N, N-methylenebisacrylamide inoshandiswa semuchinjiko wekubatanidza, kusanganisira anotevera matanho:

(1) Cellulose (Rcell) inobata nealkaline solution kugadzira alkali cellulose, uye alkalization reaction ye cellulose inokurumidza exothermic reaction. Kudzikisa tembiricha kunobatsira pakuumbwa kwealkali fibers uye kunogona kuvharidzira hydrolysis yavo. Kuwedzera madoro kunogona kuwedzera kusagadzikana kwe cellulose, iyo inobatsira kune alkalization uye inotevera etherification.

RcellOH+NaOH→RcellONA+H2O

(2) Alkali cellulose uye monochloroacetic acid inogadzira sodium carboxymethyl cellulose, uye etherification reaction ndeye nucleophilic substitution reaction:

RcellONA+ClCH2COONA→RcellOCH2COONA+NaCl

(3) N, N-methylenebisacrylamide muchinjiko-yakabatana kuti iwane yakanyanya kunyura resin. Nekuti kuchine huwandu hukuru hwemapoka ehydroxyl pane molecular chain ye carboxymethyl fiber, iyo ionization yehydroxyl boka re cellulose uye ionization ye acryloyl mbiri bond pane molecular chain yeN, N-methylenebisacrylamide inogona kukonzereswa pasi pechiito. yealkali catalysis, uye ipapo Cross-linking pakati cellulose molecular cheni kunoitika kubudikidza Michael condensation, uye pakarepo anopindira proton exchange nemvura kuti ive mvura-insoluble cellulose superabsorbent resin.

2.2 Raw zvinhu uye zviridzwa

Raw zvinhu: donje rinopinza (rakachekwa kuita linters), sodium hydroxide, monochloroacetic acid, N, N-methylenebisacrylamide, absolute ethanol, acetone.

Zviridzwa: furasiki ine mitsipa mitatu, yemagetsi inobvongodza, reflux condenser, suction filter flask, Buchner funnel, vacuum drying oven, inotenderedza mvura vacuum pump.

2.3 Kugadzirira nzira

2.3.1 Alkalilization

Wedzera 1 g yedonje inonyura mubhodhoro rine mitsipa mitatu, wobva wawedzera imwe sodium hydroxide solution uye absolute ethanol, chengetedza tembiricha iri pasi petembiricha yekamuri, uye kurunga kwechinguva.

2.3.2 Etherification

Wedzera imwe chiyero che chloroacetic acid uye simbisa kwe1h.

2.3.2 Crosslinking

Muchikamu chekupedzisira che etherification, N, N-methylenebisacrylamide yakawedzerwa muchiyero chekuita-cross-linking, uye yakasimudzwa pakupisa kwekamuri kwemaawa maviri.

2.3.4 Mushure mekugadzirisa

Shandisa glacial acetic acid kugadzirisa pH kukosha kusvika pa7, geza munyu ne ethanol, geza mvura neacetone, sefa nekusveta, uye vacuum yakaoma kwemaawa mana (inenge makumi matanhatu.°C, vacuum degree 8.8kPa) kuwana chena donje filament chigadzirwa.

2.4 Kuongorora kwekuongorora

Mwero wekunyura kwemvura (WRV) inotarwa nekusefa, kureva kuti, 1g yechigadzirwa (G) inowedzerwa mubeaker ine 100ml yemvura yakanyungudutswa (V1), yakanyoroveswa kwemaawa makumi maviri nemana, yakasefa kuburikidza ne200-mesh simbi isina tsvina skrini. , uye mvura iri pasi pechidzitiro inounganidzwa (V2). Iyo yekuverenga formula ndeyotevera: WRV=(V1-V2)/G.

3. Migumisiro uye nhaurirano

3.1 Kusarudzwa kwemamiriro ekuita alkalization

Mukugadzira alkali cellulose nekuita kwekotoni faibha uye alkaline mhinduro, maitiro ekugadzirisa ane simba rakakura pakuita kwechigadzirwa. Pane zvakawanda zvinhu mu alkalization reaction. Kuti zvive nyore kutarisa, iyo orthogonal yekuedza dhizaini nzira inogamuchirwa.

Mamwe mamiriro ezvinhu: The solvent i20ml yeabsolute ethanol, chiyero chealkali kune etherifying agent (mol/md) i3: 1, uye crosslinking agent i0.05g.

Mhedzisiro yekuedza inoratidza kuti: hukama hwekutanga uye hwechipiri: C> A> B, iyo yakanakisa chiyero: A3B3C3. Iko kusungirirwa kwe lye ndiyo inonyanya kukosha mukuita kwe alkalization. Iyo yakanyanya kuwanda yelye inobatsira pakuumbwa kwealkali cellulose. Nekudaro, zvinofanirwa kucherechedzwa kuti iyo yakanyanya kuwanda kweiyo, iyo yakakura munyu weiyo yakagadzirwa superabsorbent resin. Nokudaro, paunenge uchigeza munyu ne ethanol, ugeze kakawanda kuti uone kuti munyu uri muchigadzirwa unobviswa, kuitira kuti usakanganisa kukwanisa kwemvura yechigadzirwa.

3.2 Mhedzisiro yecrosslinking agent dosage pachigadzirwa WRV

Mamiriro ekuedzwa ndeaya: 20ml yeabsolute ethanol, 2.3:1 chiyero chealkali kune etherification agent, 20ml yelye, uye 90min yealkalization.

Mhedzisiro yacho yakaratidza kuti huwandu hwemuchinjiko-yekubatanidza mumiriri hwakakanganisa muchinjiko-wekubatanidza dhigirii yeCMC-Na. Kuwedzeredza kuyambuka-kubatanidza kunotungamira kune yakasimba network dhizaini munzvimbo yechigadzirwa, iyo inoratidzirwa nekudzika kwemvura kunyura mwero uye kushata elasticity mushure mekutora mvura; kana huwandu hwemuchinjiro wemuchinjika hudiki, kuchinjika-kubatanidza hakuna kukwana, uye kune zvigadzirwa zvinonyungudika nemvura, izvo zvinokanganisawo chiyero chekunwa kwemvura. Kana huwandu hwemuchinjiro wemuchinjika uri pasi pe 0.06g, chiyero chekunyura kwemvura chinowedzera nekuwedzera kwehuwandu hwemuchinjiko-muchinjiro mumiriri, kana huwandu hwemuchinjiko-muchinjika hunopfuura 0.06g, chiyero chemvura chinodzikira. nehuwandu hwemuchinjiro wekubatanidza. Naizvozvo, iyo dosage ye crosslinking agent inenge 6% yekotoni fiber mass.

3.3 Mhedzisiro yemamiriro etherification pane chigadzirwa WRV

Mamiriro ekuedzwa ndeaya: alkali concentration 40%; alkali vhoriyamu 20ml; absolute ethanol 20ml; cross-linking agent dosage 0.06g; alkalization 90min.

Kubva kumakemikari reaction formula, iyo alkali-ether ratio (NaOH: CICH2-COOH) inofanira kunge iri 2: 1, asi iyo chaiyo huwandu hwealkali inoshandiswa yakakura kupfuura iyi reshiyo, nekuti imwe yemahara alkali concentration inofanirwa kuvimbiswa muhurongwa hwekuita. , nekuti: kumwe Kukwirisa kwepamusoro kwemahara base kunobatsira pakupedzwa kweiyo alkalization reaction; iyo cross-linking reaction inofanira kuitwa pasi pemamiriro e-alkaline; mamwe maitiro eparutivi anopedza alkali. Zvisinei, kana huwandu hwealkali huchiwedzerwa zvakanyanya, iyo alkali fiber ichave yakasvibiswa zvakanyanya, uye panguva imwechete, kushanda kweiyo etherification agent ichaderedzwa. Ongororo dzinoratidza kuti reshiyo yealkali kune ether inenge 2.5:1.

3.4 Pesvedzero yehuwandu hwekunyungudutsa

Mamiriro ekuedzwa ndeaya: alkali concentration 40%; alkali dosage 20ml; alkali-ether chiyero 2.5: 1; cross-linking agent dosage 0.06g, alkalization 90min.

Iyo solvent anhydrous ethanol inobata basa rekuparadzira, homogenizing uye kuchengetedza slurry mamiriro ehurongwa, iyo inobatsira kuparadzira uye kuendesa kupisa kunoburitswa panguva yekuumbwa kwealkali cellulose, uye inogona kuderedza hydrolysis reaction yealkali cellulose, nekudaro kuwana yunifomu. cellulose. Nekudaro, kana huwandu hwedoro hwakawedzerwa hwakawandisa, iyo alkali uye sodium monochloroacetate ichanyungudika mairi, kuwanda kweanogadzirisa kunoderera, chiyero chekuita chinodzikira, uye zvakare chichava nemhedzisiro yakaipa pakuyambuka kunotevera. Kana huwandu hweabsolute ethanol huri 20ml, kukosha kweWRV kwakakura.

Muchidimbu, iyo yakanyanya kufanirwa mamiriro ekugadzirira superabsorbent resin kubva mumucheka wedonje alkalized uye etherified carboxymethyl cellulose cross-linked neN, N-methylenebisacrylamide ndeiyi: alkali concentration 40%, solvent-isina 20ml yemvura uye ethanol, chiyero chealkali kune ether. iri 2.5:1, uye dosage ye crosslinking agent i 0.06g (6% yehuwandu hwematoni linters).