Cellulose ya CMC ndi Mapangidwe Ake

Pogwiritsa ntchito udzu wa cellulose ngati zopangira, idasinthidwa ndi etherification. Kupyolera muyeso limodzi ndi kuyesa kasinthasintha, mikhalidwe yabwino kwambiri yopangira carboxymethyl cellulose idatsimikiziridwa kukhala: nthawi ya etherification 100min, kutentha kwa etherification 70.℃, NaOH mlingo 3.2g ndi monochloroacetic acid mlingo 3.0g, pazipita m'malo Digiri ndi 0,53.

Mawu ofunika: CMCcellulose; monochloroacetic acid; etherification; kusinthidwa

Carboxymethyl cellulosendi ether yopangidwa ndi kugulitsidwa kwambiri padziko lonse lapansi. Amagwiritsidwa ntchito kwambiri mu zotsukira, chakudya, mankhwala otsukira mano, nsalu, kusindikiza ndi utoto, kupanga mapepala, mafuta, migodi, mankhwala, ziwiya zadothi, zida zamagetsi, mphira, utoto, mankhwala, zodzoladzola, zikopa, mapulasitiki ndi kubowola mafuta, etc., kudziwika. monga "industrial monosodium glutamate". Carboxymethyl cellulose ndi chochokera m'madzi chosungunuka cha cellulose ether chomwe chimapezeka posintha mankhwala a cellulose. Cellulose, chinthu chachikulu chopangira carboxymethyl cellulose, ndi chimodzi mwazinthu zachilengedwe zongowonjezedwanso padziko lapansi, zomwe zimapangidwa pachaka matani mabiliyoni mazanamazana. dziko langa ndi dziko lalikulu laulimi ndipo ndi limodzi mwa mayiko omwe ali ndi udzu wochuluka kwambiri. Udzu nthawi zonse wakhala chimodzi mwazinthu zopangira moyo kwa anthu akumidzi. Zinthuzi sizinapangidwe moyenerera kwa nthawi yayitali, ndipo zosakwana 2% ya zinyalala zaulimi ndi nkhalango monga udzu zimagwiritsidwa ntchito padziko lonse lapansi chaka chilichonse. Mpunga ndiye mbewu yayikulu kwambiri yazachuma m'chigawo cha Heilongjiang, komwe kuli malo opitilira 2 miliyoni hm2, kutulutsa kwapachaka kwa matani 14 miliyoni a mpunga, ndi matani 11 miliyoni a udzu. Nthawi zambiri alimi amaziwotcha m'munda monga zinyalala, zomwe sizongowononga kwambiri zachilengedwe, komanso zimawononga kwambiri chilengedwe. Choncho, kuzindikira kagwiritsidwe ntchito ka udzu ndikofunika kwa chitukuko chokhazikika chaulimi.

1. Zida zoyesera ndi njira

1.1 Zida zoyesera ndi zida

Udzu wa cellulose, wodzipangira okha mu labotale; JJ～1 mtundu chosakanizira magetsi, Jintan Guowang Experimental Instrument Factory; Mtengo wa SHZW2C-Pampu ya vacuum, Shanghai Pengfu Electromechanical Co., Ltd.; pHS-3C pH mita, Mettler-Toledo Co., Ltd.; DGG-9070A magetsi Kutentha nthawi zonse kutentha kuyanika uvuni, Beijing North Lihui Test Instrument Equipment Co., Ltd.; HITACHI-S ~ 3400N kusanthula maikulosikopu ya elekitironi, Zida za Hitachi; ethanol; sodium hydroxide; chloroacetic acid, etc. (ma reagents pamwamba ali analytical woyera).

1.2 Njira yoyesera

1.2.1 Kukonzekera kwa carboxymethyl cellulose

(1) Njira yopangira carboxymethyl cellulose: Yesani 2 g ya cellulose mu botolo la makosi atatu, onjezerani 2.8 g wa NaOH, 20 ml ya 75% ya ethanol solution, ndi zilowerere mu alkali mu madzi osamba osamba kutentha kwa 25.°C kwa mphindi 80. Sakanizani ndi chosakaniza kuti muphatikize bwino. Panthawi imeneyi, cellulose imakhudzidwa ndi njira ya alkaline kupanga alkali cellulose. Mu gawo la etherification, onjezerani 10 ml ya 75% ya ethanol solution ndi 3 g wa chloroacetic acid ku botolo la makosi atatu lomwe lakhudzidwa pamwambapa, kwezani kutentha kufika 65-70.° C., ndikuchitapo kwa mphindi 60. Onjezani zamchere kachiwiri, kenaka onjezerani 0.6g NaOH ku botolo lomwe lili pamwambapa kuti kutentha kuzikhala 70.°C, ndipo nthawi yake ndi 40min kuti mupeze Na-CMC (sodium carboxymethyl cellulose).

Kusalowerera ndale ndi kutsuka: onjezani 1moL·L-1 hydrochloric acid, ndi kusokoneza zomwe zimachitika firiji mpaka pH = 7 ~ 8. Ndiye kusamba kawiri ndi 50% Mowa, ndiye kusamba kamodzi ndi 95% Mowa, fyuluta ndi kuyamwa, ndi youma pa 80-90.°C kwa maola 2.

(2) Kutsimikiza kwa mlingo wa m'malo chitsanzo: acidity mita kutsimikiza njira: Kulemera 0.2g (zolondola 0.1mg) wa oyeretsedwa ndi zouma Na-CMC chitsanzo, kupasuka mu 80mL madzi osungunulidwa, kusonkhezera electromagnetically kwa 10min, ndi kusintha. ndi asidi kapena alkali Njira yothetsera inabweretsa pH ya yankho ku 8. Kenako titrate yankho loyesa ndi sulfuric acid solution mu beaker yokhala ndi pH mita elekitirodi, ndikuyang'ana kuwonetsa kwa pH mita ndikugwedeza mpaka pH itatha. 3.74. Dziwani kuchuluka kwa sulfuric acid solution yomwe imagwiritsidwa ntchito.

1.2.2 Njira yoyesera chinthu chimodzi

(1) Zotsatira za kuchuluka kwa alkali pamlingo wolowa m'malo mwa carboxymethyl cellulose: gwiritsani ntchito alkalization pa 25.℃, kumiza zamchere kwa mphindi 80, ndende mu Mowa njira 75%, kulamulira kuchuluka kwa monochloroacetic asidi reagent 3g, etherification kutentha ndi 65 ~ 70°C, nthawi ya etherification inali mphindi 100, ndipo kuchuluka kwa sodium hydroxide kunasinthidwa kuyesa.

(2) Zotsatira za ndende ya ethanol yankho pamlingo wolowa m'malo mwa carboxymethyl cellulose: kuchuluka kwa alkali yosasunthika ndi 3.2g, kumizidwa kwamchere mumadzi osamba nthawi zonse kutentha kwa 25°C kwa 80min, kuchuluka kwa ethanol solution ndi 75%, kuchuluka kwa monochloroacetic acid reagent kumayendetsedwa pa 3g, etherification Kutentha ndi 65-70.°C, nthawi ya etherification ndi 100min, ndipo kuchuluka kwa yankho la ethanol kumasinthidwa pakuyesa.

(3) Zotsatira za kuchuluka kwa monochloroacetic acid pamlingo wolowa m'malo mwa carboxymethyl cellulose: konzani pa 25°C kwa alkalization, zilowerere mu zamchere kwa mphindi 80, kuwonjezera 3.2g wa sodium hydroxide kuti ndende ya ethanol yankho 75%, efa Kutentha ndi 65 ~ 70°C, nthawi ya etherification ndi 100min, ndipo kuchuluka kwa monochloroacetic acid kumasinthidwa kuti ayesedwe.

(4) Zotsatira za kutentha kwa etherification pamlingo wolowa m'malo mwa carboxymethyl cellulose: konzani pa 25°C kwa alkalization, zilowerere mu zamchere kwa mphindi 80, kuwonjezera 3.2g wa sodium hydroxide kuti ndende ya Mowa yankho 75%, kutentha etherification Kutentha ndi 65 ~ 70℃, nthawi ya etherification ndi 100min, ndipo kuyesa kumachitika posintha mlingo wa monochloroacetic acid.

(5) Zotsatira za nthawi ya etherification pamlingo wolowa m'malo mwa carboxymethyl cellulose: yokhazikika pa 25°C kwa alkalization, anawonjezera 3.2g wa sodium hydroxide, ndi ankawaviika alkali kwa 80min kuti ndende ya Mowa njira 75%, ndi kulamulidwa monochlor Mlingo wa acetic acid reagent ndi 3g, kutentha etherification ndi 65 ~ 70.°C, ndipo nthawi ya etherification imasinthidwa kuyesa.

1.2.3 Dongosolo loyesera ndi kukhathamiritsa kwa cellulose ya carboxymethyl

Pamaziko a kuyesa kwa chinthu chimodzi, quadratic regression orthogonal rotation kuphatikiza kuyesa zinthu zinayi ndi magawo asanu adapangidwa. Zinthu zinayi ndi nthawi ya etherification, kutentha kwa etherification, kuchuluka kwa NaOH ndi kuchuluka kwa monochloroacetic acid. Kukonza deta kumagwiritsa ntchito pulogalamu ya SAS8.2 yowerengera data, yomwe imawulula ubale womwe ulipo pakati pa chinthu chilichonse chomwe chimalimbikitsa komanso kuchuluka kwa m'malo mwa carboxymethyl cellulose. lamulo lamkati.

1.2.4 Njira yowunikira SEM

Zitsanzo za ufa wouma zinakhazikitsidwa pa siteji ya chitsanzo ndi guluu conductive, ndipo pambuyo vacuum kupopera golide, izo anaonedwa ndi kujambulidwa pansi pa Hitachi-S-3400N Hitachi sikani electron maikulosikopu.

2. Zotsatira ndi kusanthula

2.1 Zotsatira za chinthu chimodzi pamlingo wolowa m'malo mwa carboxymethyl cellulose

2.1.1 Zotsatira za kuchuluka kwa alkali pamlingo wolowa m'malo mwa carboxymethyl cellulose

NaOH3.2g itawonjezeredwa ku cellulose ya 2g, digirii yolowa m'malo mwa mankhwalawa inali yapamwamba kwambiri. Kuchuluka kwa NaOH kumachepetsedwa, zomwe sizokwanira kupanga neutralization ya alkaline cellulose ndi etherification agent, ndipo mankhwalawa ali ndi digiri yaing'ono yolowa m'malo ndi kukhuthala kochepa. M'malo mwake, ngati kuchuluka kwa NaOH kuli kochuluka, zomwe zimachitika panthawi ya hydrolysis ya chloroacetic acid zidzawonjezeka, kumwa kwa etherifying agent kumawonjezeka, ndipo kukhuthala kwa mankhwala kudzachepa.

2.1.2 Zotsatira za kuchuluka kwa ethanol solution pamlingo wolowa m'malo mwa carboxymethyl cellulose

Mbali yamadzi mu njira ya ethanol ilipo mu sing'anga zomwe zimatuluka kunja kwa cellulose, ndipo gawo lina limakhala mu cellulose. Ngati madziwo ndi ochuluka kwambiri, CMC imatupa m'madzi kuti ipange odzola panthawi ya etherification, zomwe zimapangitsa kuti zikhale zosiyana kwambiri; ngati madzi okhutira ndi ang'onoang'ono, anachita adzakhala ovuta chitani chifukwa chosowa anachita sing'anga. Nthawi zambiri, 80% ethanol ndiye chosungunulira choyenera kwambiri.

2.1.3 Zotsatira za mlingo wa monochloroacetic acid pamlingo wolowa m'malo mwa carboxymethyl cellulose

Kuchuluka kwa monochloroacetic acid ndi sodium hydroxide ndi theoretically 1: 2, koma kuti musunthire zomwe zimayendera ku njira yopangira CMC, onetsetsani kuti pali malo oyenera aulere pamachitidwe, kuti carboxymethylation ipitirire bwino. Pachifukwa ichi, njira yowonjezera ya alkali imatengedwa, ndiko kuti, chiŵerengero cha molar cha asidi ndi zinthu zamchere ndi 1: 2.2.

2.1.4 Zotsatira za kutentha kwa etherification pamlingo wolowa m'malo mwa carboxymethyl cellulose

The apamwamba ndi kutentha etherification, mofulumira anachita mlingo, koma mbali zimachitikiranso inapita patsogolo. Kutengera momwe mankhwalawo amayendera, kutentha kokwera sikungakhale kothandiza pakupanga CMC, koma ngati kutentha kuli kotsika kwambiri, momwe zimakhalira pang'onopang'ono komanso kugwiritsa ntchito etherifying agent ndi otsika. Zitha kuwoneka kuti kutentha kwabwino kwambiri kwa etherification ndi 70°C.

2.1.5 Mphamvu ya nthawi ya etherification pamlingo wolowa m'malo mwa carboxymethyl cellulose

Ndi kuwonjezeka kwa nthawi ya etherification, kuchuluka kwa kulowetsedwa kwa CMC kumawonjezeka, ndipo liwiro la zomwe likuchita likukwera, koma pakapita nthawi, zotsatira za mbali zimawonjezeka ndipo kuchuluka kwa m'malo kumachepa. Pamene etherification nthawi ndi 100min, mlingo wa m'malo ndi pazipita.

2.2 Zotsatira za mayeso a Orthogonal ndi kusanthula magulu a carboxymethyl

Zitha kuwoneka kuchokera pa tebulo la kusanthula kwa kusiyana kuti mu chinthu choyambirira, zinthu zinayi za nthawi ya etherification, kutentha kwa etherification, kuchuluka kwa NaOH ndi kuchuluka kwa monochloroacetic acid zimakhudza kwambiri kuchuluka kwa kulowetsedwa kwa carboxymethyl cellulose (p. <0.01). Pakati pa zinthu zolumikizana, zinthu zolumikizana za nthawi ya etherification ndi kuchuluka kwa monochloroacetic acid, ndi zinthu zolumikizana za kutentha kwa etherification ndi kuchuluka kwa asidi wa monochloroacetic zidakhudza kwambiri kuchuluka kwa m'malo mwa carboxymethyl cellulose (p <0.01). Dongosolo la chikoka cha zinthu zosiyanasiyana pamlingo wolowa m'malo mwa carboxymethyl cellulose inali: kutentha kwa etherification> kuchuluka kwa monochloroacetic acid> etherification time> kuchuluka kwa NaOH.

Pambuyo pakuwunika kwa zotsatira za mayeso a quadratic regression orthogonal rotation kuphatikiza, zitha kutsimikiziridwa kuti njira yoyenera yosinthira carboxymethylation ndi: etherification nthawi 100min, kutentha kwa etherification 70.℃, NaOH mlingo 3.2g ndi monochloroacetic acid Mlingo ndi 3.0g, ndipo mlingo waukulu wolowa m'malo ndi 0,53.

2.3 Mawonekedwe a Microscopic

Mapangidwe apamwamba a cellulose, carboxymethyl cellulose ndi ma cell ophatikizika a carboxymethyl cellulose adaphunziridwa mwa kusanthula ma electron microscopy. Ma cellulose amakula mumzere wokhala ndi mawonekedwe osalala; Mphepete mwa carboxymethyl cellulose ndi yolimba kuposa ya cellulose yotengedwa, ndipo kapangidwe kameneka kamawonjezeka ndipo voliyumu imakhala yayikulu. Izi ndichifukwa choti mapangidwe a mtolo amakula chifukwa cha kutupa kwa cellulose ya carboxymethyl.

3. Mapeto

3.1 Kukonzekera kwa carboxymethyl etherified cellulose Kufunika kwa zinthu zinayi zomwe zimakhudza kuchuluka kwa cellulose m'malo mwa cellulose ndi: kutentha kwa etherification> monochloroacetic acid mlingo> etherification time> NaOH mlingo. Njira yabwino yosinthira carboxymethylation ndi nthawi ya etherification 100min, kutentha kwa etherification 70.℃, NaOH mlingo 3.2g, monochloroacetic acid mlingo 3.0g, ndi pazipita digiri m'malo 0.53.

3.2 Mulingo woyenera kwambiri waukadaulo wa kusinthidwa kwa carboxymethylation ndi: etherification nthawi 100min, kutentha kwa etherification 70.℃, NaOH mlingo 3.2g, monochloroacetic acid mlingo 3.0g, pazipita digiri m'malo 0,53.