Hoʻololi ʻana i ka etherification cellulose

01. Hoʻolauna ʻana o ka cellulose

He polysaccharide macromolecular ka Cellulose i haku ʻia me ka glucose. ʻAʻole hiki ke hoʻoheheʻe ʻia i ka wai a me nā mea hoʻoheheʻe organik maʻamau. ʻO ia ka ʻāpana nui o ka paia o nā cell mea kanu, a ʻo ia hoʻi ka polysaccharide i hoʻolaha nui ʻia a nui loa ma ke ʻano.

ʻO Cellulose ka waiwai hou loa ma ka honua, a ʻo ia hoʻi ka polymer kūlohelohe me ka hōʻiliʻili nui loa. Loaʻa iā ia nā pono o ka hiki ke hou hou ʻia, hiki ke palaho piha ʻia, a me ka biocompatibility maikaʻi.

02. Nā kumu no ka hoʻololi ʻana i ka cellulose

Loaʻa i nā macromolecules cellulose ka nui o nā hui -OH. Ma muli o ka hopena o nā pilina hydrogen, he nui ka ikaika ma waena o nā macromolecules, kahi e alakaʻi ai i kahi enthalpy hoʻoheheʻe nui △H; ma ka ʻaoʻao ʻē aʻe, aia nā apo i loko o nā macromolecules cellulose. E like me ke ʻano, ʻoi aku ka paʻakikī o ke kaulahao molekala, kahi e alakaʻi ai i kahi loli entropy hoʻoheheʻe liʻiliʻi ΔS. ʻO kēia mau kumu ʻelua e hoʻonui ai i ka mahana o ka cellulose hoʻoheheʻe (= △H / △S), a he haʻahaʻa ka mahana decomposition o ka cellulose. No laila, i ka wā e hoʻomehana ʻia ai ka cellulose i kahi mahana, e ʻike ʻia nā fibers. ʻO ka hanana ua decomposed ka cellulose ma mua o ka hoʻomaka ʻana e hoʻoheheʻe, no laila, ʻaʻole hiki i ka hana ʻana o nā mea cellulose ke hoʻohana i ke ʻano o ka hoʻoheheʻe mua ʻana a laila ka hoʻoheheʻe ʻana.

03. Ke koʻikoʻi o ka hoʻololi ʻana o ka cellulose

Me ka emi mālie ʻana o nā kumuwaiwai fossil a me nā pilikia kaiapuni koʻikoʻi e hoʻoulu ʻia e nā ʻōpala fiber kemika, ua lilo ka hoʻomohala ʻana a me ka hoʻohana ʻana i nā mea fiber hou kūlohelohe i kekahi o nā wahi wela e nānā ai ka poʻe. ʻO Cellulose ka waiwai kūlohelohe hou loa i ke kūlohelohe. Loaʻa iā ia nā waiwai maikaʻi loa e like me ka hygroscopicity maikaʻi, antistatic, permeability ea ikaika, dyeability maikaʻi, ʻoluʻolu ke komo ʻana, maʻalahi ka hana ʻana i ka lole, a me ka biodegradability. Loaʻa iā ia nā ʻano i hiki ʻole ke hoʻohālikelike ʻia me nā fiber kemika. .

Loaʻa i nā molekole cellulose kahi nui o nā hui hydroxyl, kahi maʻalahi e hana i nā pilina hydrogen intramolecular a me intermolecular, a palaho i nā mahana kiʻekiʻe me ka ʻole o ka heheʻe ʻana. Eia nō naʻe, he maikaʻi ka reactivity o ka cellulose, a hiki ke luku ʻia kona pilina hydrogen ma o ka hoʻololi kemika a i ʻole ka hopena grafting, hiki ke hoʻohaʻahaʻa pono i ke kiko heheʻe. Ma ke ʻano he ʻano huahana ʻoihana like ʻole, hoʻohana nui ʻia ia i nā lole, ka hoʻokaʻawale ʻana o ka membrane, nā plastics, ka paka a me nā uhi.

04. Hoʻololi ʻana i ka etherification cellulose

ʻO ka Cellulose ether kahi ʻano cellulose derivative i loaʻa ma o ka hoʻololi ʻana o ka etherification o ka cellulose. Hoʻohana nui ʻia ia ma muli o kona ʻano mānoanoa maikaʻi loa, emulsification, suspension, hoʻokumu ʻana i nā kiʻiʻoniʻoni, colloid pale, paʻa ka makū, a me nā waiwai hoʻopili. Hoʻohana ʻia i ka meaʻai, lāʻau lapaʻau, hana pepa, pena, nā mea kūkulu hale, a pēlā aku.

ʻO ka Etherification o ka cellulose kahi moʻo o nā derivatives i hana ʻia e ka hopena o nā hui hydroxyl ma ke kaulahao molekala cellulose me nā mea alkylating ma lalo o nā kūlana alkaline. ʻO ka hoʻohana ʻana i nā hui hydroxyl e hōʻemi i ka helu o nā pilina hydrogen intermolecular e hōʻemi i nā mana intermolecular, a laila hoʻomaikaʻi i ke kūpaʻa wela o ka cellulose, hoʻomaikaʻi i ka hana hana o nā mea, a i ka manawa like e hōʻemi i ke kiko heheʻe o ka cellulose.

Nā hiʻohiʻona o nā hopena o ka hoʻololi ʻana o ka etherification ma nā hana ʻē aʻe o ka cellulose:

Ma ka hoʻohana ʻana i ka pulupulu i hoʻomaʻemaʻe ʻia ma ke ʻano he mea maka kumu, ua hoʻohana nā mea noiʻi i kahi kaʻina hana etherification hoʻokahi-ʻanuʻu e hoʻomākaukau ai i ka carboxymethyl hydroxypropyl cellulose complex ether me ka hopena like, ka viscosity kiʻekiʻe, ke kūpaʻa waikawa maikaʻi a me ke kūpaʻa paʻakai ma o ka alkalization a me nā hopena etherification. Ma ka hoʻohana ʻana i ke kaʻina hana etherification hoʻokahi-ʻanuʻu, ʻo ka carboxymethyl hydroxypropyl cellulose i hana ʻia he kūpaʻa paʻakai maikaʻi, kūpaʻa waikawa a me ka solubility. Ma ka hoʻololi ʻana i ka nui o ka propylene oxide a me ka chloroacetic acid, hiki ke hoʻomākaukau ʻia nā huahana me nā ʻano like ʻole o ka carboxymethyl a me ka hydroxypropyl. Hōʻike nā hopena hoʻāʻo he pōkole ka pōʻaiapuni hana o ka carboxymethyl hydroxypropyl cellulose i hana ʻia e ke ʻano hoʻokahi-ʻanuʻu, haʻahaʻa ka hoʻohana ʻana i ka solvent, a he kūpaʻa maikaʻi loa ka huahana i nā paʻakai monovalent a me divalent a me ke kūpaʻa waikawa maikaʻi.

05. Manaʻolana o ka hoʻololi ʻana o ka cellulose etherification

He mea nui ka Cellulose i nā kemika a me nā mea maka kemika i waiwai nui i nā kumuwaiwai, ʻōmaʻomaʻo a pili i ke kaiapuni, a hiki ke hoʻohou hou ʻia. Loaʻa i nā derivatives o ka hoʻololi ʻana o ka cellulose etherification ka hana maikaʻi loa, ākea o nā hoʻohana a me nā hopena hoʻohana maikaʻi loa, a hoʻokō i nā pono o ka hoʻokele waiwai aupuni i kahi nui. A me nā pono o ka hoʻomohala kaiāulu, me ka holomua ʻenehana mau a me ka hoʻokō ʻana i ke kālepa ʻana i ka wā e hiki mai ana, inā hiki ke ʻoi aku ka ʻoihana ʻana o nā mea maka synthetic a me nā ʻano hana synthetic o nā derivatives cellulose, e hoʻohana piha ʻia lākou a ʻike i kahi ākea o nā noi. Waiwai