Bawo ni lati ṣe ether cellulose?

Isejade ti cellulose ethers je kemikaly títúnṣe adayeba cellulose, ojo melo yo lati igi ti ko nira tabi owu, nipasẹ kan lẹsẹsẹ ti kemikali aati. Awọn oriṣi ti o wọpọ julọ ti awọn ethers cellulose pẹlu Methyl Cellulose (MC), Hydroxyethyl Cellulose (HEC), Hydroxypropyl Methyl Cellulose (HPMC), Carboxymethyl Cellulose (CMC), ati awọn miiran. Ilana gangan le yatọ si da lori ether cellulose kan pato ti a ṣe, ṣugbọn awọn igbesẹ gbogbogbo jẹ iru. Eyi ni akopọ ti o rọrun:

Awọn Igbesẹ Gbogbogbo fun Ṣiṣe Cellulose Ethers:

1. Orisun Cellulose:

• Ohun elo ti o bẹrẹ jẹ cellulose adayeba, nigbagbogbo gba lati inu igi ti ko nira tabi owu. Cellulose jẹ deede ni irisi cellulose ti a sọ di mimọ.

2. Alkalisation:

• A ṣe itọju cellulose pẹlu ojutu ipilẹ, gẹgẹbi sodium hydroxide (NaOH), lati mu awọn ẹgbẹ hydroxyl ṣiṣẹ lori pq cellulose. Igbesẹ alkalization yii jẹ pataki fun itọsẹ siwaju sii.

3. Etherification:

• Awọn cellulose alkalized ti wa ni abẹ si etherification, nibiti awọn ẹgbẹ ether orisirisi ti ṣe afihan si ẹhin cellulose. Iru pato ti ẹgbẹ ether ti a ṣe (methyl, hydroxyethyl, hydroxypropyl, carboxymethyl, bbl) da lori ether cellulose ti o fẹ.
• Ilana etherification jẹ ifa ti cellulose pẹlu awọn reagents ti o yẹ, gẹgẹbi:
  • Fun Methyl Cellulose (MC): Itoju pẹlu dimethyl sulfate tabi methyl kiloraidi.
  • Fun Hydroxyethyl Cellulose (HEC): Itoju pẹlu ethylene oxide.
  • Fun Hydroxypropyl Methyl Cellulose (HPMC): Itoju pẹlu propylene oxide ati methyl kiloraidi.
  • Fun Carboxymethyl Cellulose (CMC): Itoju pẹlu iṣuu soda chloroacetate.

4. Idaduro ati Fifọ:

• Lẹhin etherification, itọsẹ cellulose ti o yọrisi jẹ didoju ni igbagbogbo lati yọ eyikeyi alkali to ku. Lẹhinna a fọ ​​ọja naa lati yọkuro awọn aimọ ati awọn ọja-ọja.

5. Gbigbe ati Milling:

• Awọn ether cellulose ti gbẹ lati yọ ọrinrin ti o pọju kuro lẹhinna a lọ sinu erupẹ ti o dara. Iwọn patiku le jẹ iṣakoso da lori ohun elo ti a pinnu.

6. Iṣakoso Didara:

• Ọja ether cellulose ikẹhin gba awọn idanwo iṣakoso didara lati rii daju pe o pade awọn pato pato, pẹlu iki, akoonu ọrinrin, pinpin iwọn patiku, ati awọn ohun-ini miiran ti o yẹ.

O ṣe pataki lati ṣe akiyesi pe iṣelọpọ awọn ethers cellulose ni a ṣe nipasẹ awọn aṣelọpọ amọja nipa lilo awọn ilana iṣakoso. Awọn ipo kan pato, awọn reagents, ati ẹrọ ti a lo le yatọ si da lori awọn ohun-ini ti o fẹ ti ether cellulose ati ohun elo ti a pinnu. Ni afikun, awọn ọna aabo jẹ pataki lakoko awọn ilana iyipada kemikali.