Focus on Cellulose ethers

ʻO ka ʻokoʻa ma waena o HPMC a me MC, HEC, CMC

ʻO ka cellulose ka mea nui i ʻekolu mau hana o ka mānoanoa, ka paʻa ʻana o ka wai a me ke kūkulu ʻana i ka mortar a me ka pena.

Mānoanoa: Hiki ke mānoanoa ka cellulose e hoʻopaneʻe a mālama i ka hoʻonā ʻaʻahu i luna a i lalo, a pale aku i ka sagging.

Ka mālama ʻana i ka wai: e hoʻomaloʻo mālie i ka mortar a me ka pena, a kōkua i nā mea e like me ka lehu a me ka calcium e hana ma lalo o ka hana o ka wai.

Hana ʻia: He hopena lubricating ka Cellulose, hiki ke hana i nā morta a me nā uhi i nā waiwai kūkulu maikaʻi.

1. Methyl cellulose (MC)

Ma hope o ka mālama ʻia ʻana o ka pulupulu i hoʻomaʻemaʻe ʻia me ka alkali, hana ʻia ka cellulose ether ma o ke ʻano o nā hopena me ka methane chloride ma ke ʻano he etherification agent. ʻO ka maʻamau, ʻo ka degere o ka hoʻololi ʻana he 1.6 ~ 2.0, a ʻokoʻa hoʻi ka solubility me nā pae like ʻole o ka hoʻololi. No ka non-ionic cellulose ether.

(1) Hiki ke hoʻoheheʻe ʻia ka Methylcellulose i ka wai anuanu, a paʻakikī ke hoʻoheheʻe ʻia i ka wai wela. Paʻa loa kona hopena wai i ka pae o pH=3~12. He kūpono maikaʻi me ka starch, guar gum, etc. a me nā surfactants he nui. Ke piʻi ka mahana i ka mahana gelation, puka ka gelation.

(2) ʻO ka paʻa ʻana o ka wai o ka methyl cellulose e pili ana i kona nui hoʻohui, viscosity, particle fineness and dissolution rate. ʻO ka maʻamau, inā nui ka hoʻohui, liʻiliʻi ka fineness, a nui ka viscosity, kiʻekiʻe ka nui o ka paʻa ʻana o ka wai. I waena o lākou, ʻo ka nui o ka hoʻohui i ka hopena nui loa i ka nui o ka mālama ʻana i ka wai, a ʻaʻole kūlike ka pae o ka viscosity i ke kiʻekiʻe o ka paʻa wai. ʻO ka nui o ka hoʻoheheʻe ʻana ma muli o ke ʻano o ka hoʻololi ʻana o ka ʻili o nā ʻāpana cellulose a me ka fineness. Ma waena o nā cellulose ethers ma luna, ʻo ka methyl cellulose a me ka hydroxypropyl methyl cellulose i ʻoi aku ka nui o ka paʻa wai.

(3) Hoʻololi koʻikoʻi ka hoʻololi ʻana i ka mahana i ka nui o ka mālama ʻana i ka wai o ka methyl cellulose. ʻO ka maʻamau, ʻoi aku ka kiʻekiʻe o ka mahana, ʻoi aku ka maikaʻi o ka paʻa ʻana o ka wai. Inā ʻoi aku ka mahana o ka mortar ma mua o 40 ° C, e hoʻemi nui ʻia ka paʻa ʻana o ka wai o ka methyl cellulose, e hoʻopilikia nui i ke kūkulu ʻana i ka mortar.

(4) He hopena koʻikoʻi ka methyl cellulose i ka hana a me ka hoʻopili ʻana o ka mortar. ʻO ka "adhesion" ma aneʻi e pili ana i ka ikaika pipili i manaʻo ʻia ma waena o ka mea hoʻopili a ka mea hana a me ke pani o ka pā, ʻo ia hoʻi, ka pale ʻana o ka mortar. He kiʻekiʻe ka adhesiveness, he nui ka pale ʻana o ka mortar, a ʻo ka ikaika i koi ʻia e ka poʻe hana i ka hana o ka hoʻohana ʻana he nui nō hoʻi, a ʻo ka hana ʻana o ka mortar he ʻilihune. Aia ka methyl cellulose adhesion ma kahi pae haʻahaʻa i nā huahana cellulose ether.

2. Hydroxypropylmethylcellulose (HPMC)

ʻO ka Hydroxypropyl methylcellulose kahi ʻano cellulose nona ka hoʻonui ʻana a me ka hoʻohana ʻana i ka wikiwiki i nā makahiki i hala. He cellulose non-ionic i hui ʻia eter i hana ʻia mai ka pulupulu hoʻomaʻemaʻe ma hope o ka alkalization, me ka hoʻohana ʻana i ka propylene oxide a me ka methyl chloride ma ke ʻano he etherification agent, ma o ke ʻano o nā hopena. ʻO ka pae o ka hoʻololi ʻana he 1.2-2.0. He ʻokoʻa kona mau waiwai ma muli o nā ʻano like ʻole o ka methoxyl content a me ka hydroxypropyl content.

(1) Hiki ke hoʻoheheʻe ʻia ka Hydroxypropyl methylcellulose i ka wai anuanu, a e loaʻa iā ia nā pilikia i ka hoʻoheheʻe ʻana i ka wai wela. Akā ʻoi aku ka kiʻekiʻe o ka mahana o ka gelation i ka wai wela ma mua o ka methyl cellulose. Hoʻomaikaʻi maikaʻi ʻia ka solubility i ka wai anuanu ke hoʻohālikelike ʻia me ka methyl cellulose.

(2) ʻO ka viscosity o ka hydroxypropyl methylcellulose e pili ana i kona kaumaha mole, a ʻoi aku ka nui o ke kaumaha mole, ʻoi aku ka kiʻekiʻe o ka viscosity. Hoʻopili ka mahana i kona viscosity, i ka piʻi ʻana o ka mahana, emi ka viscosity. Eia nō naʻe, ʻoi aku ka haʻahaʻa o kona viscosity kiʻekiʻe ma mua o ka methyl cellulose. Paʻa kona hopena ke mālama ʻia ma ka lumi wela.

(3) ʻO ka paʻa ʻana o ka wai o ka hydroxypropyl methylcellulose e pili ana i kona nui hoʻohui, viscosity, a me nā mea ʻē aʻe, a ʻoi aku ka kiʻekiʻe o ka paʻa ʻana o ka wai ma lalo o ka nui hoʻohui like ma mua o ka methyl cellulose.

(4) Hydroxypropyl methylcellulose paʻa i ka waikawa a me ka alkali, a paʻa loa kona ʻano wai i ka pae o ka pH = 2 ~ 12. He liʻiliʻi ka hopena o ka soda a me ka wai lime i kāna hana, akā hiki i ka alkali ke wikiwiki i kona hoʻoheheʻe ʻana a hoʻonui i kona viscosity. ʻO ka Hydroxypropyl methylcellulose paʻa i nā paʻakai maʻamau, akā inā kiʻekiʻe ke kiʻekiʻe o ka paʻakai paʻakai, piʻi ka viscosity o ka hydroxypropyl methylcellulose solution.

(5) Hiki ke hoʻohui ʻia ka Hydroxypropyl methylcellulose me nā pūhui polymer hiki ke hoʻoheheʻe ʻia i ka wai e hana i kahi ʻano like ʻole a ʻoi aku ka viscosity solution. E like me ka waiʻona polyvinyl, starch ether, mea ʻai meaʻai, etc.

(6) Hydroxypropyl methylcellulose 'oi aku ka maika'i o ka enzyme kū'ē ma mua o ka methylcellulose, a me ka hiki o ka enzymatic degradation o kona hoʻonā 'ia ma mua o ka methylcellulose. ʻOi aku ka kiʻekiʻe o ka hoʻopili ʻana o ka hydroxypropyl methylcellulose i ke kūkulu ʻana i ka mortar ma mua o ka methylcellulose.

3. Hydroxyethyl cellulose (HEC)

Hana ʻia ia mai ka pulupulu hoʻomaʻemaʻe i mālama ʻia me ka alkali, a hana ʻia me ka ethylene oxide ma ke ʻano he etherification agent i mua o ka acetone. ʻO ka pae o ka hoʻololi ʻana he 1.5-2.0. Loaʻa iā ia ka hydrophilicity ikaika a maʻalahi ke komo i ka wai.

(1) Hiki ke hoʻoheheʻe ʻia ka hydroxyethyl cellulose i ka wai anuanu, akā paʻakikī ke hoʻoheheʻe i ka wai wela. Paʻa kona hopena i ka wela kiʻekiʻe me ka ʻole o ka gelling. Hiki ke hoʻohana ʻia no ka manawa lōʻihi ma lalo o ke kiʻekiʻe o ka wela i ka mortar, akā ʻoi aku ka haʻahaʻa o kona paʻa wai ma mua o ka methyl cellulose.

(2) He kūpaʻa ka Hydroxyethyl cellulose i ka waikawa maʻamau a me ka alkali. Hiki i ka alkali ke hoʻonui i kona viscosity. ʻOi aku ka maikaʻi o kona dispersibility i ka wai ma mua o ka methyl cellulose a me ka hydroxypropyl methyl cellulose. .

(3) He hana anti-sag maikaʻi ka Hydroxyethyl cellulose no ka mortar, akā ʻoi aku ka lōʻihi o ka manawa hoʻomaha no ka sima.

(4) He haʻahaʻa loa ka hana o ka hydroxyethyl cellulose i hana ʻia e kekahi mau ʻoihana kūloko ma mua o ka methyl cellulose ma muli o ka nui o ka wai a me ka nui o ka lehu.

4. Carboxymethyl cellulose (CMC)

Hana ʻia ʻo Ionic cellulose ether mai nā fiber maoli (ka pulupulu, a me nā mea ʻē aʻe) ma hope o ka mālama ʻia ʻana me ka alkali a hoʻohana ʻia ma ke ʻano he etherification agent ma o ke ʻano o nā lāʻau lapaʻau. ʻO ke kiʻekiʻe o ka hoʻololi ʻana he 0.4 ~ 1.4, a ua hoʻopilikia nui ʻia kāna hana e ka pae o ka hoʻololi.

(1) ʻOi aku ka hygroscopic o Carboxymethyl cellulose, a ʻoi aku ka nui o ka wai ke mālama ʻia ma lalo o nā kūlana maʻamau.

(2) Carboxymethyl cellulose aqueous solution ʻaʻole ia e hana i ka gel, a emi ka viscosity me ka piʻi ʻana o ka mahana. Ke piʻi ka mahana ma mua o 50 ° C, ʻaʻole hiki ke hoʻohuli ʻia ka viscosity.

(3) Hoʻopilikia nui ʻia kona kūpaʻa e ka pH. ʻO ka mea maʻamau, hiki ke hoʻohana ʻia i ka mortar gypsum-based, akā ʻaʻole i ka mortar sima. Ke alkaline nui, nalowale ka viscosity.

(4) He haʻahaʻa loa kona paʻa wai ma mua o ka methyl cellulose. He hopena hoʻopaneʻe ia i ka mortar gypsum-based a hoʻemi i kona ikaika. Eia naʻe, ʻoi aku ka haʻahaʻa o ke kumukūʻai o ka carboxymethyl cellulose ma mua o ka methyl cellulose

ʻO ke kuleana o ka hydroxypropyl methylcellulose i loko o ka ʻoihana uhi: No ka mea he mau waiwai like ka HPMC me nā ethers hiki ke hoʻoheheʻe ʻia i ka wai, hiki ke hoʻohana ʻia ma ke ʻano he mea hana kiʻiʻoniʻoni, mānoanoa, emulsifier a me ka stabilizer i nā pena emulsion a me nā ʻāpana pena resin wai. agent, etc., i hiki i ka uhi ke pale aku i ka lole. ʻO ka pae ʻana a me ka hoʻopili ʻana, a me ka hoʻomaikaʻi ʻana i ka ʻili o ka ʻili, kūpaʻa i ka waikawa a me ka alkali, a me ka hoʻohālikelike ʻana i nā puaʻa metala. No ka mea, ʻoi aku ka kiʻekiʻe o ka helu gel o HPMC ma mua o ka MC, ʻoi aku ka ikaika o kona kūpaʻa ʻana i ka erosion bacteria ma mua o nā eter cellulose ʻē aʻe, no laila hiki ke hoʻohana ʻia i mea mānoanoa no nā pena wai-emulsion. HPMC i maikai viscosity waihona paʻa, a me ka mea maikai dispersibility, no laila, ua oi loa kūpono e like me ka dispersant i emulsified coatings.


Ka manawa hoʻouna: Mar-04-2023
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