ʻO ka cellulose ether kahi polymer synthetic i hana ʻia mai ka cellulose kūlohelohe ma o ka hoʻololi kemika. ʻO ka cellulose ether kahi hua o ka cellulose maoli. ʻOkoʻa ka hana ʻana o ka cellulose ether mai nā polymers synthetic. ʻO kāna mea nui loa he cellulose, kahi hui polymer maoli. Ma muli o ke ʻano o ke ʻano o ka cellulose kūlohelohe, ʻaʻohe hiki i ka cellulose pono ke hana me nā mea etherification. Eia naʻe, ma hope o ka hoʻomaʻamaʻa ʻana i ka mea hoʻohuhū, ua luku ʻia nā paʻa hydrogen ikaika ma waena o nā kaulahao molekala a me nā kaulahao, a lilo ka hoʻokuʻu ikaika o ka hui hydroxyl i cellulose alkali reactive. E kiʻi i ka cellulose ether.
ʻO nā waiwai o ka cellulose ethers e pili ana i ke ʻano, ka helu a me ka hāʻawi ʻana i nā mea pani. Hoʻokumu pū ʻia ka hoʻokaʻawale ʻana o nā cellulose ethers ma ke ʻano o nā substituents, degere o ka etherification, solubility a me nā waiwai noi pili. E like me ke ʻano o nā mea pani ma ke kaulahao mole, hiki ke hoʻokaʻawale ʻia i ka monoether a me ka ether hui. ʻO ka MC a mākou e hoʻohana mau ai he monoether, a ʻo ka HPMC he ether hui ʻia. ʻO ka methyl cellulose ether MC ka huahana ma hope o ka hoʻololi ʻana o ka hui hydroxyl ma ka ʻāpana glucose o ka cellulose maoli e ka methoxy. He huahana ia i loaʻa ma ka hoʻololi ʻana i kahi ʻāpana o ka pūʻulu hydroxyl ma ka hui me kahi pūʻulu methoxy a me kahi ʻāpana me kahi hui hydroxypropyl. ʻO ke kumu hoʻolālā ʻo [C6H7O2(OH)3-mn(OCH3)m[OCH2CH(OH)CH3]n]x Hydroxyethyl methyl cellulose ether HEMC, ʻo ia nā ʻano nui i hoʻohana nui ʻia a kūʻai ʻia ma ka mākeke.
Ma ke ʻano o ka solubility, hiki ke hoʻokaʻawale ʻia i ka ionic a me ka non-ionic. ʻO nā etera cellulose non-ionic hiki ke hoʻoheheʻe ʻia i ka wai ka mea nui i haku ʻia me ʻelua pūʻulu o nā alkyl ethers a me hydroxyalkyl ethers. Hoʻohana nui ʻia ʻo Ionic CMC i nā mea hoʻomaʻemaʻe synthetic, paʻi lole a me ke kala, ʻimi ʻai a me ka ʻaila. ʻO ka non-ionic MC, HPMC, HEMC, a me nā mea ʻē aʻe i hoʻohana nui ʻia i nā mea kūkulu hale, nā uhi latex, nā lāʻau lapaʻau, nā kinikona o kēlā me kēia lā, a me nā mea ʻē aʻe.
Ka paʻa wai o ka cellulose ether
I ka hana ʻana i nā mea kūkulu hale, ʻoi aku ka maloʻo-mixed mortar, cellulose ether ka mea hiki ke hoʻololi ʻia, ʻoi aku hoʻi i ka hana ʻana i ka mortar kūikawā (modified mortar), he mea nui a koʻikoʻi.
ʻO ka hana koʻikoʻi o ka wai-soluble cellulose ether i loko o ka mortar he ʻekolu mau ʻano, ʻo kekahi ka mana paʻa wai maikaʻi loa, ʻo ka mea ʻē aʻe ka mana i ka kūlike a me ka thixotropy o ka mortar, a ʻo ke kolu ka pilina me ka sima.
ʻO ka hopena paʻa wai o ka cellulose ether e pili ana i ka hoʻopili ʻana o ka wai o ka papa kumu, ka hoʻohui ʻana o ka mortar, ka mānoanoa o ka mortar layer, ke koi wai o ka mortar, a me ka manawa hoʻonohonoho o ka mea hoʻonohonoho. ʻO ka paʻa ʻana o ka wai o cellulose ether ponoʻī mai ka solubility a me ka dehydration o cellulose ether ponoʻī. E like me kā mākou i ʻike ai, ʻoiai ʻo ka cellulose molecular chain ka nui o nā pūʻulu OH hydratable, ʻaʻole hiki ke hoʻoheheʻe ʻia i ka wai, no ka mea, he kiʻekiʻe ke kiʻekiʻe o ka crystallinity o ka hale cellulose. ʻAʻole lawa ka hiki hydration o nā pūʻulu hydroxyl wale nō e uhi i nā paʻa hydrogen ikaika a me nā kaha van der Waals ma waena o nā mole. No laila, pehu wale ia akā ʻaʻole hoʻoheheʻe i ka wai. Ke hoʻokomo ʻia kahi mea pani i loko o ke kaulahao molekala, ʻaʻole ʻo ka mea pani wale nō e hoʻopau i ke kaulahao hydrogen, akā ua luku ʻia hoʻi ka pilina hydrogen interchain ma muli o ka wili ʻana o ka mea pani ma waena o nā kaulahao pili. ʻO ka nui o ka mea pani, ʻoi aku ka nui o ka mamao ma waena o nā mole. ʻOi aku ka mamao. ʻO ka nui o ka hopena o ka luku ʻana i nā paʻa hydrogen, lilo ka cellulose ether i ka wai-soluble ma hope o ka hoʻonui ʻana o ka lattice cellulose a komo ka hopena, e hana ana i kahi hopena kiʻekiʻe-viscosity. Ke piʻi ka mahana, nāwaliwali ka hydration o ka polymer, a kipaku ʻia ka wai ma waena o nā kaulahao. I ka lawa ʻana o ka hopena dehydration, hoʻomaka nā molekala e hōʻuluʻulu, e hana ana i kahi gel hoʻonohonoho ʻoihana ʻekolu-dimensional a pelu ʻia. ʻO nā mea e pili ana i ka paʻa ʻana o ka wai o ka mortar, ʻo ia ka viscosity o cellulose ether, ka nui i hoʻohui ʻia, ka maikaʻi o nā ʻāpana a me ka mahana hoʻohana.
ʻOi aku ka kiʻekiʻe o ka viscosity o ka cellulose ether, ʻoi aku ka maikaʻi o ka hana paʻa wai, a ʻoi aku ka kiʻekiʻe o ka viscosity o ka solution polymer. Ma muli o ke kaumaha o ka molecular (polymerization degree) o ka polymer, ua hoʻoholo ʻia e ka lōʻihi o ke kaulahao o ke ʻano mole a me ke ʻano o ke kaulahao, a ʻo ka hāʻawi ʻana i nā ʻano a me nā nui o nā substituent e pili pono ana i kona laulā viscosity. [η]=Kmα
[η] Ka poʻe ʻeleʻele o ka hoʻonā polimer
m polimer molekala kaumaha
α polymer ano mau
K viscosity solution coefficient
Pili ka viscosity o ka solution polymer i ke kaumaha molecular o ka polymer. ʻO ka viscosity a me ka neʻe ʻana o ka cellulose ether solution e pili ana i ka noi ma nā ʻano like ʻole. No laila, he nui nā kikoʻī viscosity o kēlā me kēia cellulose ether, a ʻo ka hoʻoponopono ʻana o ka viscosity i ʻike nui ʻia e ka degradation o ka cellulose alkali, ʻo ia hoʻi, ka haki ʻana o nā kaulahao moleki cellulose.
ʻOi aku ka nui o ka cellulose ether i hoʻohui ʻia i ka mortar, ʻoi aku ka maikaʻi o ka hana paʻa wai, a ʻoi aku ka kiʻekiʻe o ka viscosity, ʻoi aku ka maikaʻi o ka hana paʻa wai.
No ka nui o ka ʻāpana, ʻoi aku ka maikaʻi o ka ʻāpana, ʻoi aku ka maikaʻi o ka mālama ʻana i ka wai. E nānā i ke Kiʻi 3. Ma hope o ka hoʻopili ʻana o ka ʻāpana nui o ka cellulose ether me ka wai, e hoʻoheheʻe koke ka ʻili a hana i ka gel e ʻōwili ai i ka mea e pale ai i nā molekala wai mai ka hoʻomau ʻana i ka infiltrate. Hoʻoheheʻe ʻia ka liʻiliʻi ma mua o ka hoʻoheheʻe like ʻole, e hana ana i kahi solution flocculent ao a i ʻole agglomerates. Hoʻopilikia nui ia i ka paʻa ʻana o ka wai o cellulose ether, a ʻo ka solubility kekahi o nā kumu no ke koho ʻana i ka cellulose ether.
ʻO ka mānoanoa a me ka Thixotropy o Cellulose Etera
ʻO ka lua o ka hana o ka cellulose ether - ka mānoanoa, e pili ana i: ke degere o ka polymerization o ka cellulose ether, ka hoʻonā hopena, ka shear rate, ka mahana a me nā kūlana ʻē aʻe. He kū hoʻokahi ka waiwai gelling o ka hopena i ka alkyl cellulose a me kāna mau mea i hoʻololi ʻia. ʻO nā waiwai gelation e pili ana i ke kiʻekiʻe o ka hoʻololi, ka hoʻonā hoʻonā a me nā mea hoʻohui. No nā derivatives hoʻololi hydroxyalkyl, pili pū nā waiwai gel i ka pae hoʻololi o ka hydroxyalkyl. No ka haʻahaʻa viscosity MC a me HPMC, 10% -15% solution hiki ke hoʻomākaukau, medium viscosity MC a me HPMC hiki ke hoʻomākaukau i ka 5% -10% solution, a me ka viscosity MC a me HPMC hiki ke hoʻomākaukau wale i ka 2% -3% solution, a maʻamau. Hoʻopili pū ʻia ka helu viscosity o cellulose ether me 1% -2% solution. High molecular kaumaha cellulose etera i kiʻekiʻe thickening pono. I loko o ka hoʻonā hoʻonaʻauao hoʻokahi, ʻokoʻa nā polymers me nā kaupaona molekala like ʻole. Degere kiʻekiʻe. Hiki ke hoʻokō ʻia ka viscosity target ma ka hoʻohui ʻana i ka nui o ka cellulose ether molecular haʻahaʻa haʻahaʻa. Kona viscosity i uuku hilinaʻi ma luna o ka shear rate, a hiki i ka viscosity kiʻekiʻe i ka viscosity pahupaʻiwikiō, a me ka mea i koi 'ia he uuku, a me ka viscosity hilinaʻi ma luna o ka thickening pono. No laila, no ka hoʻokō ʻana i kahi kūlike, pono e hōʻoia ʻia kahi nui o ka cellulose ether (concentration of the solution) a me ka viscosity solution. ʻO ka mahana gel o ka hopena e emi iho ana me ka hoʻonuiʻia o ka hoʻonāʻana o ka hopena, a me nā gels i ka mahana wela ma hope o ka hikiʻana i kahi hoʻolālā. He kiʻekiʻe ka ʻike gelling o HPMC ma ka lumi wela.
Hiki ke hoʻololi ʻia ke kūlike ma ke koho ʻana i ka nui o ka ʻāpana a me ke koho ʻana i nā cellulose ethers me nā pae like ʻole o ka hoʻololi. ʻO ka mea i kapa ʻia ʻo ka hoʻololi ʻana ʻo ia ka hoʻokomo ʻana i kahi pae o ka hoʻololi ʻana o nā pūʻulu hydroxyalkyl ma ke ʻano iwi o MC. Ma ka hoʻololi ʻana i nā waiwai hoʻololi pili o nā mea pani ʻelua, ʻo ia hoʻi, nā waiwai hoʻololi pili pili DS a me MS o nā pūʻulu methoxy a me hydroxyalkyl a mākou e ʻōlelo pinepine ai. Hiki ke loaʻa nā koi hana like ʻole o ka cellulose ether ma o ka hoʻololi ʻana i nā waiwai hoʻololi pili o nā mea pani ʻelua.
Pono e hoʻoheheʻe koke ʻia nā cellulose ethers i hoʻohana ʻia i nā mea kūkulu hale pauka i ka wai anuanu a hāʻawi i kahi kūlike kūpono no ka ʻōnaehana. Inā hā'awi 'ia i ka nui o ka shear rate, e lilo mau ana ia i ka flocculent a me ka colloidal block, 'o ia ho'i kahi huahana i 'oi aku ka maika'i 'ole.
Aia kekahi pilina laina maikaʻi ma waena o ke kūlike o ka paʻi sima a me ke ʻano o ka cellulose ether. Hiki i ka cellulose ether ke hoʻonui nui i ka viscosity o ka mortar. ʻO ka nui o ka dosage, ʻoi aku ka maopopo o ka hopena.
Loaʻa ka thixotropy kiʻekiʻe o ka cellulose ether aqueous solution, ʻo ia hoʻi kahi ʻano nui o ka cellulose ether. Loaʻa ka wai wai o nā polimer MC i ka wai pseudoplastic a me ka non-thixotropic ma lalo o ko lākou wela gel, akā nā waiwai kahe o Newtonian ma nā ʻāpana ʻoki haʻahaʻa. Hoʻonui ka Pseudoplasticity me ka paona molekala a i ʻole ka ʻike ʻana o ka cellulose ether, me ka nānā ʻole i ke ʻano o ka mea pani a me ke degere o ka hoʻololi. No laila, nā cellulose ethers o ka like viscosity grade, ʻaʻohe mea MC, HPMC, HEMC, e hōʻike mau i nā waiwai rheological like me ka lōʻihi o ka mālama ʻana a me ka mahana. Hoʻokumu ʻia nā gels Structural i ka wā e piʻi aʻe ai ka mahana, a hiki mai nā kahe thixotropic kiʻekiʻe. Hōʻike ka ʻike kiʻekiʻe a me ka haʻahaʻa viscosity cellulose ethers i ka thixotropy ma lalo o ka mahana gel. He pōmaikaʻi nui kēia waiwai i ka hoʻoponopono ʻana i ka pae ʻana a me ka sagging i ke kūkulu ʻana i ka mortar hale. Pono e wehewehe ʻia ma ʻaneʻi ʻo ke kiʻekiʻe o ka viscosity o cellulose ether, ʻoi aku ka maikaʻi o ka paʻa ʻana o ka wai, akā ʻoi aku ka kiʻekiʻe o ka viscosity, ʻoi aku ka kiʻekiʻe o ke kaumaha molecular pili o cellulose ether, a me ka emi ʻana o kona solubility, he hopena maikaʻi ʻole. e pili ana i ka hoʻopaʻa ʻana o ka mortar a me ka hana hana. ʻO ke kiʻekiʻe o ka viscosity, ʻoi aku ka maopopo o ka hopena mānoanoa ma ka mortar, akā ʻaʻole ia i kūlike loa. ʻO kekahi ʻano viscosity haʻahaʻa a haʻahaʻa, akā ʻoi aku ka maikaʻi o ka cellulose ether i hoʻololi ʻia i ka hoʻomaikaʻi ʻana i ka ikaika o ka mortar pulu. Me ka piʻi ʻana o ka viscosity, hoʻomaikaʻi ka paʻa wai o ka cellulose ether
Ka manawa hoʻouna: Nov-22-2022