ʻO ka Hydroxyethyl cellulose (HEC) he mea koʻikoʻi ka wai-soluble cellulose ether, i hoʻohana nui ʻia i nā uhi, ka ʻaila hinu, nā lāʻau lapaʻau a me nā māla ʻē aʻe. ʻO kona wahi hoʻoheheʻe he mea koʻikoʻi koʻikoʻi kino e pili ana i kāna hana a hoʻohana. Hiki ke hoʻokaʻawale ʻia nā mea e pili ana i ka helu hoʻoheheʻe o ka hydroxyethyl cellulose i kekahi mau ʻano, e like me ke ʻano o ka molecular, degere o ka hoʻololi ʻana, ke kaumaha mole, crystallinity, haumia, a me nā kūlana kaiapuni.
1. Hoʻolālā molekala
ʻO ka hydroxyethyl cellulose ka huahana o ka cellulose ma hope o ka ethoxylation. ʻO kona ʻano kumu ʻo ia ka hoʻololi ʻana o nā mana hydrogen i loko o ka molekole cellulose e nā hui hydroxyethyl. ʻO ke kūlana, ka helu a me ke kauoha o ka hydroxyethyl substitution e pili i kona helu heheʻe.
Ke kūlana hoʻololi: ʻO kēlā me kēia ʻāpana glucose i loko o ka cellulose he ʻekolu pūʻulu hydroxyl hiki ke hoʻololi ʻia. ʻO ka hoʻololi ʻana i nā kūlana like ʻole e hoʻololi i ke ʻano spatial o ka mole, a laila e pili ana i ka helu heheʻe.
Ka helu o nā pani: ʻO ka hoʻonui ʻana i ka helu o nā mea pani e hoʻemi maʻamau i ka hoʻopaʻa ʻana o ka hydrogen ma waena o nā molekala, a laila e hōʻemi ana i ka helu heheʻe.
ʻO ke kauoha o ka hoʻonohonoho hoʻololi: ʻO nā mea pani i hāʻawi wale ʻia a me nā mea hoʻopili mau i nā hopena like ʻole i ka maʻalahi a me ka launa pū ʻana o ke kaulahao molekala, no laila e pili ana i ka helu heheʻe.
2. Degree of Substitution (DS)
Hōʻike ʻo DS i ka helu awelika o nā mea pani hydroxyethyl ma kēlā me kēia ʻāpana glucose. He hopena koʻikoʻi ka degere o ka hoʻololi ʻana i ka helu hoʻoheheʻe, i hōʻike nui ʻia ma nā ʻano aʻe:
DS haʻahaʻa: Ma ka DS haʻahaʻa, ʻoi aku ka ikaika o ka hoʻopaʻa ʻana o ka hydrogen ma waena o nā molekala hydroxyethyl cellulose, e hoʻopaʻa paʻa ai nā molekala a kiʻekiʻe ka helu heheʻe.
DS kiʻekiʻe: Hoʻonui ka DS kiʻekiʻe i ka maʻalahi o nā molekala a hoʻemi i ka hopena o ka hoʻopaʻa ʻana i ka hydrogen, e maʻalahi ai ka paheʻe ʻana o nā molekala a me ka helu heheʻe.
3. Kaumaha Molekala
He hopena pololei ko ka paona molekala ma ka helu hehee o ka hydroxyethyl cellulose. Ma ka ʻōlelo maʻamau, ʻoi aku ka nui o ke kaumaha molekala, ʻoi aku ka lōʻihi o ke kaulahao mole, ʻoi aku ka ikaika o ka ikaika van der Waals ma waena o nā molekala, a ʻoi aku ka kiʻekiʻe o ka helu heheʻe. Eia kekahi, e pili ana ka laula o ka puunaue paona mole i ka helu hehee, a hiki i ka mahele laula ke alakai i na wahi hehee like ole.
Ke kaumaha molekala kiʻekiʻe: ʻOi aku ka lōʻihi o nā kaulahao molekala, ʻoi aku ka pili ʻana o kekahi i kekahi, a kiʻekiʻe ka helu heheʻe.
Haʻahaʻa molekala kaumaha: ʻOi aku ka pōkole o nā kaulahao molekala, ʻoi aku ka nāwaliwali o nā ikaika intermolecular, a haʻahaʻa ka helu heheʻe.
4. Crystallinity
ʻO ka hydroxyethyl cellulose he polymer amorphous, akā aia nō paha kekahi mau wahi crystalline. ʻO ka hele ʻana o nā ʻāpana crystalline e hoʻonui i ka helu heheʻe no ka mea paʻa ke ʻano o ka crystalline a koi hou aku i ka ikehu e wāwahi i kēia mau hale i kauoha ʻia. ʻO ke kiʻekiʻe o ka hydroxyethylation a me nā kūlana kaʻina e pili ana i kona crystallinity.
ʻO ka crystallinity kiʻekiʻe: ʻoi aku ka paʻa o ke ʻano, ka helu heheʻe kiʻekiʻe.
ʻO ka crystallinity haʻahaʻa: ʻoi aku ka maikaʻi o ke ʻano, ka helu heheʻe haʻahaʻa.
5. Na haumia
I ka wā o ka hana ʻana o ka hydroxyethyl cellulose, hiki ke waiho ʻia kekahi mau mea maka, catalysts a i ʻole nā huahana. Hiki ke hoʻololi i nā ikaika intermolecular i ka hele ʻana o kēia mau mea haumia, a laila e hoʻopilikia ai i ka helu heheʻe. ʻo kahi laʻana:
Ke koena catalyst: hiki ke hoʻokumu ʻia nā complexes, hoʻololi i ka helu heheʻe.
Nā huahana: ʻO ka hele ʻana o nā huahana like ʻole e hoʻololi i ka pilina o ka ʻōnaehana a pili i ka helu heheʻe.
6. Nā kūlana kaiapuni
ʻO nā kūlana kaiapuni e like me ka mahana a me ka haʻahaʻa e pili pū i ka helu heheʻe o ka hydroxyethyl cellulose. Ma lalo o nā kūlana haʻahaʻa kiʻekiʻe, e hoʻopili ʻia ka hydroxyethyl cellulose ma hope o ka lawe ʻana i ka wai, kahi e hoʻonāwaliwali ai i nā ikaika intermolecular a hoʻemi i ka helu heheʻe.
Ke wela kiʻekiʻe: Hiki ke hoʻoheheʻe ʻia ka wela o ka mea a hoʻonui i ka helu heheʻe.
ʻO ka haʻahaʻa kiʻekiʻe: ʻOi aku ka maʻalahi o ke kaulahao molekala ma hope o ka lawe ʻana i ka wai, a hoʻemi ʻia ka helu heheʻe.
7. Mea Hana Hana Hana
ʻO ka mahana, ka ikaika shear, nā kūlana maloʻo, a me nā mea'ē aʻe i ka wā o ke kaʻina hana e pili i ka helu heheʻe o ka huahana hope. ʻO nā kūlana hana like ʻole e alakaʻi i nā ʻano molekala like ʻole a me ka crystallinity, kahi e hoʻopili ai i ka helu heheʻe.
ʻO ka wela o ka hoʻoili ʻana: Hiki ke hoʻohaʻahaʻa hapa a i ʻole ka hoʻopili ʻana i nā wela hoʻololi kiʻekiʻe, e hoʻololi i ka helu heheʻe.
Nā kūlana hoʻomaloʻo: ʻO ka hoʻomaloʻo wikiwiki a me ka maloʻo maloʻo he hopena like ʻole i ka hoʻonohonoho ʻana o nā molekala, a ʻokoʻa hoʻi ka helu heheʻe.
I ka hōʻuluʻulu ʻana, ʻo nā mea e pili ana i ka helu hoʻoheheʻe o ka hydroxyethyl cellulose e pili ana i ka molecular structure, degree of substitution, molecular weight, crystallinity, impurities, environment environment and processing technology. No nā noi kūpono a me ka hoʻoponopono ʻana, hiki i ka mana kūpono o kēia mau mea ke hoʻokō i ka hana o ka hydroxyethyl cellulose a hoʻokō pono i nā koi noi. I ke kaʻina hana, ʻaʻole hiki i ka hoʻoponopono ʻepekema o kēia mau ʻāpana ke hoʻomalu wale i ka helu heheʻe o ka huahana, akā hoʻomaikaʻi pū i ka paʻa a me ka maikaʻi o ka huahana.
Ka manawa hoʻouna: Jul-10-2024