Hoʻomākaukau i ka carboxymethyl cellulose

Carboxymethyl cellulose (CMC)he polymer hiki ke hoʻoheheʻe ʻia i ka wai i loaʻa mai ka cellulose, he polysaccharide maoli i loaʻa i loko o nā paia o nā mea kanu. Loaʻa ka CMC i nā noi nui ma nā ʻoihana like ʻole me ka meaʻai, nā lāʻau lapaʻau, nā mea hoʻonaninani, nā textiles, ka pepa, a me nā mea ʻē aʻe he nui ma muli o kāna mau waiwai kūʻokoʻa e like me ka mānoanoa, hoʻopaʻa, hoʻopaʻa ʻia, hana kiʻiʻoniʻoni, a me ka mālama ʻana i ka wai. ʻO ka hoʻomākaukau ʻana o CMC e pili ana i kekahi mau ʻanuʻu e hoʻomaka ana mai ka unuhi ʻana o cellulose mai nā kumu kūlohelohe a ukali ʻia e kona hoʻololi ʻana e hoʻolauna i nā hui carboxymethyl.

1. Unuhi o Cellulose:
ʻO ka hana mua i ka hoʻomākaukau ʻana i ka CMC ʻo ia ka unuhi ʻana i ka cellulose mai nā kumu kūlohelohe e like me ka pulp lāʻau, nā linters pulupulu, a i ʻole nā ​​​​mea kanu ʻē aʻe. Loaʻa maʻamau ka cellulose ma o nā kaʻina hana e like me ka pulping, bleaching, a me ka hoʻomaʻemaʻe. No ka laʻana, hiki ke loaʻa i ka pulp lāʻau ma nā kaʻina hana pulping mechanical a i ʻole kemika a ukali ʻia e ka bleaching me ka chlorine a i ʻole hydrogen peroxide e wehe i nā haumia a me ka lignin.

2. Ho'ā 'ana o Cellulose:
Ke lawe ʻia ka cellulose, pono ia e hoʻoikaika i ka hoʻokomo ʻana i nā hui carboxymethyl. Loaʻa ka hoʻoulu ʻana ma ka mālama ʻana i ka cellulose me ka alkali e like me ka sodium hydroxide (NaOH) a i ʻole ka sodium carbonate (Na2CO3) ma lalo o nā kūlana hoʻomalu o ka mahana a me ke kaomi. Hoʻohūhū ka lāʻau alkali i nā fiber cellulose a hoʻonui i ko lākou reactivity ma o ka uhaki ʻana i nā paʻa hydrogen intra a intermolecular.

3. ʻO ka pane ʻana o Carboxymethylation:
Hoʻokomo ʻia ka cellulose i hoʻāla ʻia i ka hopena carboxymethylation kahi i hoʻokomo ʻia ai nā hui carboxymethyl (-CH2COOH) i nā hui hydroxyl o nā kaulahao cellulose. Hoʻokō maʻamau ʻia kēia pane ʻana ma ka hana ʻana i ka cellulose i hoʻāla ʻia me ka sodium monochloroacetate (SMCA) i mua o kahi catalyst alkaline e like me ka sodium hydroxide (NaOH). Hiki ke hōʻike ʻia ka hopena penei:

Cellulose + Chloroacetic Acid → Carboxymethyl Cellulose + NaCl

ʻO nā kūlana hopena e like me ka mahana, ka manawa pane, ka neʻe ʻana o nā reagents, a me ka pH e mālama pono ʻia e hōʻoia i ka hopena kiʻekiʻe a me ke degere o ka hoʻololi ʻana (DS) e pili ana i ka helu awelika o nā pūʻulu carboxymethyl i hoʻokomo ʻia i kēlā me kēia ʻāpana glucose o ke kaulahao cellulose.

4. Hoʻopau a me ka holoi ʻana:
Ma hope o ka hopena carboxymethylation, hoʻopau ʻia ka carboxymethyl cellulose e hoʻoneʻe i ka alkali nui a me ka waika chloroacetic ʻole. Loaʻa maʻamau kēia ma ka holoi ʻana i ka huahana me ka wai a i ʻole ka wai ʻawaʻawa dilute a ukali ʻia e ka kānana e hoʻokaʻawale i ka CMC paʻa mai ka hui ʻana.

5. Hoomaemae:
Holoi ʻia ka CMC i hoʻomaʻemaʻe ʻia me ka wai i nā manawa he nui e wehe i nā mea haumia e like me nā paʻakai, nā reagents i hoʻokō ʻole ʻia, a me nā huahana. Hiki ke hoʻohana ʻia ka kānana a centrifugation e hoʻokaʻawale i ka CMC i hoʻomaʻemaʻe ʻia mai ka wai holoi.

6. Hoʻomaloʻo:
ʻO ka hope, ua maloʻo ka carboxymethyl cellulose i hoʻomaʻemaʻe ʻia e wehe i ke koena o ka wai a loaʻa ka huahana i makemake ʻia ma ke ʻano o ka pauka maloʻo a i ʻole granules. Hiki ke hoʻokō ʻia ka hoʻomaloʻo ʻana me ka hoʻohana ʻana i nā ʻano like ʻole e like me ka hoʻomaloʻo ʻana i ka ea, ka maloʻo maloʻo, a i ʻole ka hoʻomaloʻo ʻana ma muli o nā ʻano makemake o ka huahana hope.

7. Ke ano a me ka Mana Mana:
ʻO ka maloʻoCMCHoʻopili ʻia ka huahana i nā ʻano hana like ʻole e like me Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), a me nā ana viscosity e hōʻoia i kona ʻano kemika, degere o ka hoʻololi ʻana, ke kaumaha molekala, a me ka maʻemaʻe. Hana ʻia nā hoʻokolohua hoʻokele maikaʻi e hōʻoia i ka hoʻokō ʻana o ka huahana i nā kikoʻī i koi ʻia no kāna mau noi i manaʻo ʻia.

ʻO ka hoʻomākaukau ʻana o ka carboxymethyl cellulose e pili ana i kekahi mau ʻanuʻu e pili ana i ka unuhi ʻana o ka cellulose mai nā kumu kūlohelohe, ka hoʻoulu ʻana, ka hopena carboxymethylation, neutralization, hoʻomaʻemaʻe, maloʻo, a me ke ʻano. Pono kēlā me kēia ʻanuʻu i ka mālama pono ʻana i nā kūlana hopena a me nā ʻāpana e loaʻa ai ka hua kiʻekiʻe, ke degere o ka hoʻololi ʻana, a me ka maikaʻi o ka huahana hope. ʻO CMC kahi polymer i hoʻohana nui ʻia me nā noi like ʻole ma muli o kāna mau waiwai kūʻokoʻa a me ka versatility.