CMC Cellulose thiab Nws Cov Qauv Cwj Pwm

Siv straw cellulose ua raw khoom, nws tau hloov kho los ntawm etherification. Los ntawm ib qho tseem ceeb thiab kev ntsuas kev sib hloov, qhov kev pom zoo rau kev npaj carboxymethyl cellulose tau txiav txim siab yog: etherification lub sij hawm 100min, etherification kub 70℃, NaOH ntau npaum 3.2g thiab monochloroacetic acid ntau npaum li cas 3.0g, qhov siab tshaj plaws hloov Cov degree yog 0.53.

Cov ntsiab lus tseem ceeb: CMCcellulose; monochloroacetic acid; etherification; kev hloov kho

Carboxymethyl celluloseyog qhov tsim thiab muag ntau tshaj plaws cellulose ether nyob hauv lub ntiaj teb. Nws yog dav siv nyob rau hauv detergent, zaub mov, tshuaj txhuam hniav, textile, printing thiab dyeing, ntawv ua, roj av, mining, tshuaj, ceramics, electronics Cheebtsam, roj hmab, Xim, tshuaj tua kab, tshuaj pleev ib ce, tawv, plastics thiab roj drilling, thiab lwm yam. Raws li "kev lag luam monosodium glutamate". Carboxymethyl cellulose yog dej-soluble cellulose ether derivative tau los ntawm chemically modifying natural cellulose. Cellulose, cov khoom siv tseem ceeb rau kev tsim cov carboxymethyl cellulose, yog ib qho ntawm cov khoom siv txuas ntxiv dua tshiab hauv ntiaj teb, nrog kev tsim txhua xyoo ntawm ntau pua lab tons. kuv lub teb chaws yog ib lub teb chaws ua liaj ua teb loj thiab ib lub teb chaws uas muaj cov nyom nyom ntau tshaj plaws. Straw yeej ib txwm yog ib qho ntawm cov roj tseem ceeb rau cov neeg nyob deb nroog. Cov peev txheej no tsis tau tsim muaj lub sijhawm ntev, thiab tsawg dua 2% ntawm kev ua liaj ua teb thiab hav zoov pov tseg xws li straw yog siv hauv ntiaj teb txhua xyoo. Nplej yog cov qoob loo tseem ceeb hauv xeev Heilongjiang, nrog thaj chaw cog qoob loo ntau dua 2 lab hm2, ib xyoos twg cov nplej tau 14 lab tons, thiab 11 lab tons ntawm straw. Cov neeg ua liaj ua teb feem ntau hlawv lawv ncaj qha rau hauv thaj teb raws li pov tseg, uas tsis yog tsuas yog pov tseg loj ntawm cov peev txheej ntuj, tab sis kuj ua rau muaj kuab paug loj rau ib puag ncig. Yog li ntawd, kev paub txog kev siv cov khoom siv straw yog qhov xav tau ntawm txoj kev txhim kho kom ruaj khov ntawm kev ua liaj ua teb.

1. Cov ntaub ntawv sim thiab cov txheej txheem

1.1 Cov khoom siv sim thiab cov khoom siv

Straw cellulose, nws tus kheej tsim hauv chav kuaj; JJ～1 hom hluav taws xob tov khoom, Jintan Guowang Kev Ntsuas Lub Hoobkas; SHZW2C hom RS—Lub tshuab nqus tsev twj, Shanghai Pengfu Electromechanical Co., Ltd.; pH-3C pH meter, Mettler-Toledo Co., Ltd.; DGG-9070A hluav taws xob cua sov qhov kub kom qhuav qhov cub, Beijing North Lihui Test Instrument Equipment Co., Ltd.; HITACHI-S ~ 3400N scanning electron microscope, Hitachi Instruments; ethanol; sodium hydroxide; chloroacetic acid, thiab lwm yam. (cov reagents saum toj no yog analytically ntshiab).

1.2 Kev sim txoj kev

1.2.1 Kev npaj ntawm carboxymethyl cellulose

(1) Txoj kev npaj ntawm carboxymethyl cellulose: Nyias 2 g ntawm cellulose rau hauv ib lub raj mis peb-caj dab, ntxiv 2.8 g ntawm NaOH, 20 mL ntawm 75% ethanol tov, thiab tsau nyob rau hauv alkali nyob rau hauv ib tug tas mus li dej kub da dej ntawm 25.°C rau 80 min. Do nrog lub tov khoom kom sib tov zoo. Thaum cov txheej txheem no, cellulose reacts nrog alkaline tov los tsim alkali cellulose. Nyob rau hauv lub etherification theem, ntxiv 10 mL ntawm 75% ethanol tov thiab 3 g ntawm chloroacetic acid rau peb-caj dab reacted saum toj no, nce qhov kub ntawm 65-70.° C., thiab teb rau 60 feeb. Ntxiv alkali rau lub sijhawm thib ob, tom qab ntawd ntxiv 0.6g NaOH rau cov tshuaj tiv thaiv saum toj no kom qhov kub ntawm 70.°C, thiab lub sij hawm cov tshuaj tiv thaiv yog 40min kom tau cov roj Na—CMC (sodium carboxymethylcellulose).

Neutralization thiab ntxuav: ntxiv 1moL·L-1 hydrochloric acid, thiab neutralize cov tshuaj tiv thaiv ntawm chav tsev kub kom txog thaum pH = 7 ~ 8. Tom qab ntawd ntxuav ob zaug nrog 50% ethanol, tom qab ntawd ntxuav ib zaug nrog 95% ethanol, lim nrog nqus, thiab qhuav ntawm 80-90°C rau 2 teev.

(2) Kev txiav txim siab ntawm cov qauv hloov pauv: acidity meter txiav txim siab txoj kev: Nyhav 0.2g (raug rau 0.1mg) ntawm purified thiab qhuav Na-CMC qauv, yaj nyob rau hauv 80mL distilled dej, do nws electromagnetically rau 10min, thiab kho Nws nrog cov kua qaub los yog alkali Cov tshuaj coj pH ntawm cov tshuaj mus rau 8. Tom qab ntawd titrate cov tshuaj ntsuam xyuas nrog sulfuric acid standard tov nyob rau hauv lub beaker nruab nrog ib tug pH meter electrode, thiab soj ntsuam qhov qhia ntawm pH meter thaum titrating kom txog thaum pH yog. 3.74 ib. Nco ntsoov qhov ntim ntawm sulfuric acid txheem tov siv.

1.2.2 Ib qho piv txwv xeem txoj kev

(1) Cov nyhuv ntawm cov alkali rau qib ntawm kev hloov ntawm carboxymethyl cellulose: nqa tawm alkalization ntawm 25℃, alkali immersion rau 80 feeb, qhov concentration hauv ethanol yog 75%, tswj tus nqi ntawm monochloroacetic acid reagent 3g, etherification kub yog 65 ~ 70°C, lub sij hawm etherification yog 100 feeb, thiab tus nqi ntawm sodium hydroxide raug hloov rau qhov kev xeem.

(2) Cov nyhuv ntawm cov concentration ntawm ethanol daws nyob rau hauv lub degree ntawm kev hloov ntawm carboxymethyl cellulose: tus nqi ntawm taag alkali yog 3.2g, alkaline immersion nyob rau hauv ib tug tas mus li dej kub da dej ntawm 25°C rau 80min, qhov concentration ntawm ethanol tov yog 75%, tus nqi ntawm monochloroacetic acid reagent yog tswj ntawm 3g, etherification Qhov kub yog 65-70°C, lub sij hawm etherification yog 100min, thiab cov concentration ntawm cov tshuaj ethanol hloov pauv rau qhov kev sim.

(3) Cov nyhuv ntawm cov nyiaj monochloroacetic acid nyob rau theem ntawm kev hloov pauv ntawm carboxymethyl cellulose: kho ntawm 25°C rau alkalization, soak hauv alkali rau 80 feeb, ntxiv 3.2g ntawm sodium hydroxide kom cov concentration ntawm ethanol tov 75%, ether Qhov kub yog 65 ~ 70°C, lub sij hawm etherification yog 100min, thiab tus nqi ntawm monochloroacetic acid hloov rau kev sim.

(4) Qhov cuam tshuam ntawm etherification kub ntawm qhov kev hloov pauv ntawm carboxymethyl cellulose: kho ntawm 25°C rau alkalization, soak hauv alkali rau 80 feeb, ntxiv 3.2g ntawm sodium hydroxide kom cov concentration ntawm ethanol tov 75%, etherification kub Qhov kub yog 65 ~ 70℃, lub sijhawm etherification yog 100min, thiab qhov kev sim yog ua los ntawm kev hloov cov tshuaj monochloroacetic acid.

(5) Cov nyhuv ntawm etherification lub sij hawm ntawm qhov kev hloov ntawm carboxymethyl cellulose: tsau ntawm 25°C rau alkalization, ntxiv 3.2g ntawm sodium hydroxide, thiab soaked nyob rau hauv alkali rau 80min kom lub concentration ntawm ethanol tov 75%, thiab tswj monochlor Cov tshuaj acetic acid reagent yog 3g, etherification kub yog 65 ~ 70.°C, thiab lub sijhawm etherification hloov pauv rau kev sim.

1.2.3 Kev npaj thiab kev ua kom zoo ntawm carboxymethyl cellulose

Raws li qhov kev sim ntawm ib qho kev sim, ib qho quadratic regression orthogonal rotation ua ke kev sim nrog plaub yam thiab tsib theem tau tsim. Plaub yam yog etherification lub sij hawm, etherification kub, tus nqi ntawm NaOH thiab tus nqi ntawm monochloroacetic acid. Cov ntaub ntawv ua tiav siv SAS8.2 statistical software rau kev ua cov ntaub ntawv, uas qhia txog kev sib raug zoo ntawm txhua qhov cuam tshuam thiab qib ntawm kev hloov ntawm carboxymethyl cellulose. txoj cai sab hauv.

1.2.4 SEM txoj kev tsom xam

Cov hmoov qhuav qhuav tau tsau rau ntawm cov qauv theem nrog cov kua nplaum, thiab tom qab lub tshuab nqus tsev ntxhua khaub ncaws, nws tau pom thiab yees duab nyob rau hauv Hitachi-S-3400N Hitachi scanning electron microscope.

2. Cov txiaj ntsig thiab kev tshuaj xyuas

2.1 Cov txiaj ntsig ntawm ib qho tseem ceeb ntawm kev hloov pauv ntawm carboxymethyl cellulose

2.1.1 Cov nyhuv ntawm cov alkali ntawm qhov kev hloov pauv ntawm carboxymethyl cellulose

Thaum NaOH3.2g ntxiv rau 2g cellulose, qhov kev hloov pauv ntawm cov khoom yog qhov siab tshaj plaws. Tus nqi ntawm NaOH raug txo qis, uas tsis txaus los tsim cov neutralization ntawm alkaline cellulose thiab etherification tus neeg sawv cev, thiab cov khoom muaj ib tug me me degree ntawm kev hloov thiab viscosity tsawg. Ntawm qhov tsis sib xws, yog tias tus nqi ntawm NaOH ntau dhau, cov kev cuam tshuam sab nraud thaum lub sij hawm hydrolysis ntawm chloroacetic acid yuav nce, kev noj cov tshuaj etherifying yuav nce, thiab cov khoom viscosity kuj yuav txo.

2.1.2 Cov nyhuv ntawm concentration ntawm ethanol tov rau qib ntawm kev hloov ntawm carboxymethyl cellulose

Ib feem ntawm cov dej hauv cov tshuaj ethanol muaj nyob rau hauv cov tshuaj tiv thaiv nruab nrab sab nraum cellulose, thiab lwm qhov muaj nyob hauv cellulose. Yog tias cov ntsiab lus dej loj dhau, CMC yuav swell hauv dej los tsim jelly thaum lub sij hawm etherification, ua rau cov tshuaj tiv thaiv tsis sib xws; yog tias cov ntsiab lus ntawm cov dej me me dhau lawm, cov tshuaj tiv thaiv yuav nyuaj rau kev txuas ntxiv vim tsis muaj cov tshuaj tiv thaiv nruab nrab. Feem ntau, 80% ethanol yog cov kuab tshuaj haum tshaj plaws.

2.1.3 Cov nyhuv ntawm qhov ntau npaum ntawm monochloroacetic acid ntawm kev hloov pauv ntawm carboxymethyl cellulose

Tus nqi ntawm monochloroacetic acid thiab sodium hydroxide yog theoretically 1: 2, tab sis txhawm rau txav cov tshuaj tiv thaiv rau cov kev taw qhia ntawm kev tsim CMC, xyuas kom meej tias muaj qhov tsim nyog pub dawb hauv cov tshuaj tiv thaiv, kom carboxymethylation tuaj yeem ua tau zoo. Vim li no, txoj kev tshaj alkali yog saws, uas yog, molar ratio ntawm acid thiab alkali tshuaj yog 1: 2.2.

2.1.4 Qhov cuam tshuam ntawm etherification kub ntawm qhov kev hloov pauv ntawm carboxymethyl cellulose

Qhov siab dua qhov etherification kub, qhov ceev cov tshuaj tiv thaiv tus nqi, tab sis cov tshuaj tiv thaiv sab kuj nrawm. Los ntawm qhov kev xav ntawm cov tshuaj sib npaug, qhov kub thiab txias yog qhov tsis zoo rau kev tsim CMC, tab sis yog tias qhov kub thiab txias tsis dhau, cov tshuaj tiv thaiv qeeb thiab kev siv tus nqi ntawm etherifying tus neeg sawv cev yog tsawg. Nws tuaj yeem pom tias qhov zoo tshaj plaws kub rau etherification yog 70°C.

2.1.5 Cov nyhuv ntawm etherification lub sij hawm ntawm kev hloov pauv ntawm carboxymethyl cellulose

Nrog rau kev nce ntawm lub sijhawm etherification, qib ntawm kev hloov pauv ntawm CMC nce, thiab cov tshuaj tiv thaiv nrawm nrawm dua, tab sis tom qab qee lub sijhawm, cov kev cuam tshuam sab nraud nce thiab qib ntawm kev hloov pauv qis. Thaum lub sij hawm etherification yog 100min, qhov kev hloov pauv yog qhov siab tshaj plaws.

2.2 Orthogonal xeem cov qhabnias thiab tsom xam ntawm carboxymethyl pawg

Nws tuaj yeem pom los ntawm cov lus txheeb xyuas qhov sib txawv uas nyob rau hauv cov khoom tseem ceeb, plaub yam ntawm lub sijhawm etherification, etherification kub, tus nqi ntawm NaOH thiab tus nqi ntawm monochloroacetic acid muaj qhov cuam tshuam loj heev rau kev hloov pauv ntawm carboxymethyl cellulose (p <0.01). Ntawm cov khoom sib cuam tshuam, cov khoom sib cuam tshuam ntawm lub sijhawm etherification thiab tus nqi ntawm monochloroacetic acid, thiab cov khoom sib cuam tshuam ntawm etherification kub thiab cov nyiaj ntawm monochloroacetic acid muaj qhov cuam tshuam loj heev ntawm kev hloov pauv ntawm carboxymethyl cellulose (p <0.01). Qhov kev txiav txim ntawm kev cuam tshuam ntawm ntau yam ntawm qhov kev hloov pauv ntawm carboxymethyl cellulose yog: etherification kub> tus nqi ntawm monochloroacetic acid> etherification lub sij hawm> tus nqi ntawm NaOH.

Tom qab kev soj ntsuam ntawm cov txiaj ntsig ntawm kev ntsuas quadratic regression orthogonal kev sib hloov ua ke tsim, nws tuaj yeem txiav txim siab tias cov txheej txheem zoo rau kev hloov kho carboxymethylation yog: etherification lub sij hawm 100min, etherification kub 70℃, NaOH ntau npaum 3.2g thiab monochloroacetic acid Cov koob tshuaj yog 3.0g, thiab qhov siab tshaj plaws ntawm kev hloov pauv yog 0.53.

2.3 Microscopic Performance characterization

Qhov chaw morphology ntawm cellulose, carboxymethyl cellulose thiab cross-linked carboxymethyl cellulose hais tau kawm los ntawm kev tshuaj xyuas electron microscopy. Cellulose hlob nyob rau hauv ib tug strip zoo nrog ib tug du nto; ntug ntawm carboxymethyl cellulose yog rougher tshaj li ntawm cov extracted cellulose, thiab cov kab noj hniav cov qauv nce thiab lub ntim yuav loj dua. Qhov no yog vim lub nras qauv ua loj dua vim qhov o ntawm carboxymethyl cellulose.

3. Cov lus xaus

3.1 Kev npaj ntawm carboxymethyl etherified cellulose Qhov kev txiav txim ntawm qhov tseem ceeb ntawm plaub yam cuam tshuam rau qib ntawm kev hloov ntawm cellulose yog: etherification kub> monochloroacetic acid ntau npaum> etherification sij hawm> NaOH ntau npaum. Cov txheej txheem zoo tshaj plaws ntawm kev hloov kho carboxymethylation yog lub sijhawm etherification 100min, etherification kub 70℃, NaOH ntau npaum 3.2g, monochloroacetic acid ntau npaum li cas 3.0g, thiab siab tshaj plaws hloov pauv qib 0.53.

3.2 Cov txheej txheem zoo tshaj plaws ntawm kev hloov kho carboxymethylation yog: etherification lub sij hawm 100min, etherification kub 70℃, NaOH ntau npaum 3.2g, monochloroacetic acid ntau npaum li cas 3.0g, siab tshaj hloov degree 0.53.