Ko nga mea tino nui mai i te Cellulose Ether

Ko te tukanga me te mahi hua o te carboxymethyl cellulose i honoa e te N, N-methylenebisacrylamide ki te whakarite i te kapia superabsorbent i akohia, me te kukū o te alkali, te nui o te kaihoko whakawhiti, te etherification alkali, me te whakarewa i korerohia. Te painga o te inenga ki runga i te mahi whakauru wai o te hua. Ka whakamaramahia te tikanga whakauru o te kapia wai-absorbent ki te wai. Kua whakaatuhia e nga rangahau ko te uara pupuri wai (WRV) o tenei hua ka eke ki te 114ml/g.

kupu matua:cellulose ether; methylenebisacrylamide; whakarite

1、Kupu Whakataki

Ko te kapia Superabsorbent he rauemi polymer me nga roopu hydrophilic kaha me tetahi tohu o te honohono. Ko nga taonga momi wai noa penei i te pepa, te miro, me te hemp he iti te tere o te whakauru wai me te ngoikore o te kaha ki te pupuri i te wai, i te mea ka taea e nga kapia tino kaha te tango i te wai he maha nga wa o to ratou ake taumaha, a ko te gel i hangaia i muri i te tango i te wai ka kore e maroke noa. me te pehanga iti. He pai te kaha pupuri wai. Karekau e memeha ki te wai, ki nga wairewa waro ranei.

He maha nga roopu hydroxyl, nga roopu carboxyl me nga katote konutai hydrate kei runga i te mekameka ngota o te mea tino whakangao i te cellulose. I muri i te ngongo wai, ka karapotia te wai e te whatunga macromolecular hydrophilic ka taea te pupuri i raro i te pehanga o waho. Ka whakamakuku te wai i te kapia adsorption, ka hanga he apa o te kiriuhi ahua-permeable i waenganui i te kapia me te wai. Na te nui o te kukū o nga katote pūkoro (Na+) i roto i te kapia wai-absorbent, e ai ki a Donnan's te tikanga taurite, ka taea e tenei rereketanga o te kukū katote te pehanga osmotic. He rawakore, he kaha ngoikore te makuku me te pupuhi, ka rere te wai i roto i tenei paparanga o te membrane semi-permeable me te whakakotahi ki nga roopu hydrophilic me nga katote i runga i nga macromolecules o te kapia superabsorbent, ka whakaiti i te kukū o nga katote pūkoro, na reira e whakaatu ana te kaha o te wai me te pupuhi. Ka haere tonu tenei tukanga adsorption tae noa ki te rereketanga o te pehanga osmotic i puta mai i te rereketanga o te kukū o nga katote pūkoro he rite ki te parenga ki te roha atu i puta mai i te kaha whakakotahi o te kupenga ngota o te kapia polymer. Ko nga painga o te kapia superabsorbent i mahia mai i te cellulose ko: te tere o te whakauru wai, te tere tere o te wai, te pai o te wai tote, te kore-paitini, te ngawari ki te whakatika i te uara pH, ka taea te whakaheke i te taiao, me te utu iti, no reira he whanui te whānuitanga o ngā whakamahinga. Ka taea te whakamahi hei kaihoko aukati wai, hei whakamaarama i te oneone, me te kaihoko pupuri wai i roto i te umanga me te ahuwhenua. I tua atu, he pai te whakawhanaketanga me te tono mo te hauora, te kai, te microbiology, me te rongoa.

2. Wāhanga whakamātautau

2.1 Te kaupapa whakamatautau

Ko te whakarite o te kapia superabsorbent muka miro ko te nuinga ki te hanga i te hanganga hono-whakawhiti me te iti o te whakakapinga i runga i te kiri muka. Te hono-whakawhiti ki nga pūhui e rua, neke atu ranei nga roopu mahi tauhohenga. Ko nga roopu mahi e kaha ana ki te whakawhiti hononga ko te vinyl, hydroxyl, carboxyl, amide, acid chloride, oxirane, nitrile, me etahi atu. I roto i tenei whakamatautau, ka whakamahia te N, N-methylenebisacrylamide hei kaihoko whakawhiti, tae atu ki nga waahanga e whai ake nei:

(1) Ka tauhohe te Cellulose (Rcell) ki te wairewa kawakore ki te whakaputa i te cellulose alkali, a ko te tauhohenga waikore o te cellulose he tauhohenga exothermic tere. Ko te whakaheke i te pāmahana he pai ki te hanganga o nga muka kawakore, ka taea te aukati i te waiwai. Ko te taapiri i nga waipiro ka nui ake te mate o te cellulose, he painga ki te whakamaaramatanga me te whakamaarama o muri mai.

RcellOH+NaOH→RcellONa+H2O

(2) Ko te cellulose alkali me te waikawa monochloroacetic e whakaputa ana i te konutai carboxymethyl cellulose, a ko te tauhohenga etherification no te tauhohenga whakakapi nucleophilic:

RcellONa+ClCH2COONa→RcellOCH2COONa+NaCl

(3) N, N-methylenebisacrylamide hono-whiti ki te whiwhi i te kapia tino kaha. Na te mea he maha tonu nga roopu hydroxyl i runga i te mekameka ngota o te muka carboxymethyl, ka taea te whakakorikori i te roopu hydroxyl o te cellulose me te katotetanga o te hononga takirua acryloyl i runga i te mekameka ngota o N, N-methylenebisacrylamide ka taea te whakaoho i raro i te mahi. o te catalysis alkali, katahi ka hono-whakawhitinga i waenga i nga mekameka ngota ngota cellulose ka puta i roto i te condensation Michael, a ka uru tonu ki te whakawhiti iraoho ki te wai kia noho hei kapia superabsorbent cellulose waikore.

2.2 Maata me nga taputapu

Rauemi mata: miro mimiti (tapahia ki roto i nga riki), te konutai waikawa, te waikawa monochloroacetic, N, N-methylenebisacrylamide, te waihano tino, te acetone.

Nga taputapu: te ipu kaki-toru, te whakakorikori hiko, te whakakorikori whakamaarama, te ipu tātari momi, te kohanga Buchner, te oumu whakamaroke korehau, te papu wai rere.

2.3 Tikanga whakarite

2.3.1 Whakawaitanga

Tāpirihia te 1 g o te miro ngongo ki te pounamu kaki-toru, katahi ka tapirihia he wairewa konutai hydroxide me te waihano tino, kia mau te pāmahana ki raro i te pāmahana rūma, ka whakaoho mo te wa poto.

2.3.2 Whakawhanaunga

Tāpirihia he waikawa chloroacetic me te whakaoho mo te 1 haora.

2.3.2 Whakawhitiwhiti

I te wa o muri mai o te whakamaaramatanga, ka taapirihia te N,N-methylenebisacrylamide kia rite ki te kawe i te hononga-whakawhitinga, me te whakaoho i te pāmahana rūma mo te 2 haora.

2.3.4 Tukatuka-muri

Whakamahia te waikawa acetic glacial ki te whakatika i te uara pH ki te 7, horoia te tote ki te waiwaro, horoia te wai ki te acetone, tātari ki te momi, ka maroke mo te 4 haora (i te 60 pea.°C, tohu korehau 8.8kPa) ki te whiwhi hua kakawaua miro ma.

2.4 Te whakamatautau tātari

Ka whakatauhia te tere momi wai (WRV) ma te tatari, ara, 1g o te hua (G) ka tapirihia ki te ipurau kei roto te 100ml wai matutu (V1), ka ruia mo te 24 haora, ka tātarihia ma te mata kowiri tira 200-mata. , ka kohia te wai kei raro o te mata (V2). Ko te tātai tātai e whai ake nei: WRV=(V1-V2)/G.

3. Nga hua me te matapaki

3.1 Te kowhiringa o nga tikanga tauhohenga waikore

I roto i te tukanga o te whakaputa cellulose alkali na roto i te mahi o te muka miro me te otinga kawakore, ko nga tikanga tukanga he tino paanga ki te mahi o te hua. He maha nga mea i roto i te tauhohenga o te alkaliization. Mo te pai o te tirohanga, ka whakamahia te tikanga hoahoa whakamatautau orthogonal.

Ko etahi atu tikanga: Ko te whakarewa ko te 20ml o te ethanol tino, ko te ōwehenga o te kawakore ki te kaihoko etherifying (mol/md) he 3:1, ko te kaihoko whakawhiti he 0.05g.

Ko nga hua whakamatautau e whakaatu ana: ko te hononga tuatahi me te tuarua: C>A>B, te tauwehenga pai: A3B3C3. Ko te kukū o te reitia te mea tino nui i roto i te tauhohenga o te waikura. Ko te kukū nui o te reitia he pai ki te hanga o te cellulose alkali. Heoi, me tohu ko te teitei o te kukū o te rei, ka nui ake te tote o te kapia superabsorbent kua oti te whakarite. Na reira, i te wa e horoi ana i te tote ki te waihano, horoia kia maha nga wa ki te whakarite kia tangohia te tote i roto i te hua, kia kore ai e pa ki te kaha o te whakauru wai o te hua.

3.2 Te awenga o te inenga a te kaihoko honohono ki te hua WRV

Ko nga tikanga whakamatautau ko: 20ml o te waihano tino, 2.3:1 ōwehenga o te kawakore ki te kaihoko whakaetherification, 20ml o te rei, me te 90min o te whakamaaramatanga.

Ko nga hua i whakaatu ko te nui o te kaihoko whakawhiti i pa ki te tohu whakawhiti o te CMC-Na. Ko te nui o te hononga-whakawhitinga ka arahi ki te hanganga whatunga kikii i roto i te waahi hua, e tohuhia ana e te iti o te whakauru wai me te ngoikore o te elasticity i muri i te whakauru wai; i te mea he iti te nui o te kaihoko whakawhiti, kaore i te oti te whakawhitinga, a, kei reira nga hua wairewa, e pa ana ki te tere o te whakauru wai. I te iti iho i te 0.06g te nui o te kaihoko whakawhiti, ka piki ake te tere o te whakauru wai ki te piki ake o te nui o te kaihoko whakawhiti, ka nui ake te nui o te kaihoko whakawhiti i te 0.06g, ka heke te tere o te whakauru wai. me te nui o te kaihoko whakawhiti. Na reira, ko te inenga o te kaihoko whakawhiti he tata ki te 6% o te papatipu muka miro.

3.3 Te paanga o nga tikanga whakamaarama ki te hua WRV

Ko nga tikanga whakamatautau ko: te kukū alkali 40%; rōrahi alkali 20ml; te waihā tino 20ml; te inenga a te kaihoko whakawhiti 0.06g; waikawa 90min.

Mai i te tātai tauhohenga matū, ko te ōwehenga alkali-ether (NaOH:CICH2-COOH) kia 2:1, engari ko te tino nui o te kawakore e whakamahia ana he nui ake i tenei ōwehenga, no te mea me whakamana tetahi kukū kawakore kore utu i roto i te punaha tauhohenga. , na te mea: etahi Ko te kukū teitei ake o te turanga kore utu e pai ana ki te whakaotinga o te tauhohenga waikore; me whakahaere te tauhohenga whakawhiti i raro i nga tikanga kawakore; ko etahi tauhohenga taha ka pau te kawakore. Engari, ki te nui rawa te taapiri o te alkali, ka tino heke te muka alkali, a, i te wa ano, ka whakahekehia te pai o te kaikawe etherification. Ko nga whakamatautau e whakaatu ana ko te ōwehenga o te kawakore ki te ether he 2.5:1.

3.4 Te awe o te nui whakarewa

Ko nga tikanga whakamatautau ko: te kukū alkali 40%; inenga alkali 20ml; ōwehenga alkali-ether 2.5:1; te inenga a te kaihoko whakawhiti-whakawhiti 0.06g, te whakangao 90min.

Ko te wairewa anhydrous ethanol e mahi ana ki te whakamarara, ki te whakakotahi me te pupuri i te ahua slurry o te punaha, he pai ki te marara me te whakawhiti i te wera i tukuna i te wa o te hanganga o te cellulose alkali, ka taea te whakaiti i te tauhohenga hydrolysis o te cellulose alkali, na reira ka whiwhi kakahu. cellulose . Heoi, ki te nui rawa te nui o te waipiro e tapirihia ana, ka memeha te alkali me te konutai monochloroacetate ki roto, ka heke te kukū o nga tauhohenga, ka heke te tere o te tauhohenga, ka pa he kino ki runga i nga hononga whakawhiti ka whai ake. Ina 20ml te nui o te waihano tino, he nui te uara WRV.

Hei whakarapopototanga, ko nga tikanga tino pai mo te whakarite i te kapia superabsorbent mai i te miro absorbent alkalized and etherified carboxymethyl cellulose cross-linked by N, N-methylenebisacrylamide are: alkali concentration 40%, solvent-free 20ml of water and ethanol, te ōwehenga o te alkali ki te etera. he 2.5:1, a ko te inenga o te kaihoko whakawhiti he 0.06g (6% o te nui o nga miro miro).