Methylcellulose (MC)
ʻO ke ʻano molekala o ka methylcellulose (MC):
ʻO [C6H7O2(OH)3-h(OCH3)n\]x
ʻO ke kaʻina hana ʻana, ʻo ia ka hana ʻana i ka cellulose ether ma o kekahi mau hopena ma hope o ka mālama ʻia ʻana o ka pulupulu i hoʻomaʻemaʻe ʻia me ka alkali, a hoʻohana ʻia ka methyl chloride ma ke ʻano he mea etherification. Ma ke ʻano laulā, ʻo ke kekelē o ka pani ʻana he 1.6 ~ 2.0, a ʻokoʻa hoʻi ka solubility me nā kekelē like ʻole o ka pani ʻana. No ka non-ionic cellulose ether.
Hiki ke hoʻoheheʻe ʻia ka Methylcellulose i ka wai anuanu, a he paʻakikī ke hoʻoheheʻe ʻia i ka wai wela. He paʻa loa kona hopena wai ma ka pae pH = 3 ~ 12.
He kūpono maikaʻi kona me ka starch, guar gum, a me nā mea ʻē aʻe a me nā surfactants he nui. Ke hiki ka mahana i ka mahana gelation, hana ʻia ka gelation.
ʻO ka paʻa ʻana o ka wai o ka methylcellulose e pili ana i ka nui o kona hoʻohui ʻia, ka viscosity, ka maikaʻi o nā ʻāpana a me ka helu hoʻoheheʻe.
Ma keʻano laulā, inā nui ka nui o ka hoʻohui ʻana, liʻiliʻi ka maikaʻi, a nui ka mānoanoa, kiʻekiʻe ka nui o ka paʻa ʻana o ka wai. I waena o lākou, ʻo ka nui o ka hoʻohui ka hopena nui loa i ka nui o ka paʻa ʻana o ka wai, a ʻaʻole kūlike ka pae o ka mānoanoa me ka pae o ka paʻa ʻana o ka wai. ʻO ka nui o ka hoʻoheheʻe ʻana e hilinaʻi nui ʻia i ke kiʻekiʻe o ka hoʻololi ʻana o ka ʻili o nā ʻāpana cellulose a me ka maikaʻi o nā ʻāpana.
Ma waena o nā ethers cellulose i luna, ʻoi aku ka kiʻekiʻe o ka paʻa ʻana o ka wai o ka methyl cellulose a me ka hydroxypropyl methyl cellulose.
ʻO Carboxymethylcellulose (CMC)
ʻO Carboxymethyl cellulose, i ʻike ʻia hoʻi ʻo sodium carboxymethyl cellulose, i ʻike nui ʻia ʻo cellulose, cmc, etc., he polymer linear anionic, kahi paʻakai sodium o ka cellulose carboxylate, a he mea hou a pau ʻole. Nā mea maka kemika.
Hoʻohana nui ʻia ia i ka ʻoihana detergent, ka ʻoihana meaʻai a me ka wai ʻeli ʻaila, a ʻo ka nui i hoʻohana ʻia i nā mea hoʻonani wale nō no 1%.
Hana ʻia ka Ionic cellulose ether mai nā olonā kūlohelohe (pulupulu, a pēlā aku) ma hope o ka mālama ʻana i ka alkali, me ka hoʻohana ʻana i ka sodium monochloroacetate ma ke ʻano he etherification agent, a ke hana nei i kahi moʻo o nā mālama ʻana.
ʻO ke kekelē o ka pani ʻana he 0.4 ~ 1.4, a ua hoʻopilikia nui ʻia kāna hana e ke kekelē o ka pani ʻana.
He maikaʻi loa ka hiki ke hoʻopaʻa ʻo CMC, a he maikaʻi ka hiki ke hoʻokuʻu ʻia kāna hopena wai, akā ʻaʻohe waiwai deformation plastic maoli.
Ke hoʻoheheʻe ʻia ka CMC, hana maoli ka depolymerization. Hoʻomaka ka piʻi ʻana o ka viscosity i ka wā o ka hoʻoheheʻe ʻana, hele ma waena o kahi kiʻekiʻe loa, a laila hāʻule i kahi plateau. Pili ka viscosity hopena i ka depolymerization.
Pili loa ke kekelē o ka depolymerization i ka nui o ka solvent maikaʻi ʻole (wai) i loko o ka hoʻohuihui. I loko o kahi ʻōnaehana solvent maikaʻi ʻole, e like me ka toothpaste i loaʻa ka glycerin a me ka wai, ʻaʻole e depolymerize loa ʻo CMC a e hōʻea i kahi kiko kaulike.
I ke ʻano o kahi nui o ka wai i hāʻawi ʻia, ʻoi aku ka maʻalahi o ka depolymerize ʻana o ka CMC i hoʻololi ʻia me ka hydrophilic kiʻekiʻe ma mua o ka CMC i hoʻololi ʻia me ka haʻahaʻa.
ʻO ka Hydroxyethylcellulose (HEC)
Hana ʻia ʻo HEC ma ka mālama ʻana i ka pulupulu i hoʻomaʻemaʻe ʻia me ka alkali, a laila e hana me ka ethylene oxide ma ke ʻano he etherification agent i ke alo o ka acetone. ʻO ke kekelē o ka pani ʻana he 1.5 ~ 2.0. Loaʻa iā ia ka hydrophilicity ikaika a maʻalahi hoʻi e omo i ka makū.
Hiki ke hoʻoheheʻe ʻia ka Hydroxyethyl cellulose i ka wai anuanu, akā paʻakikī ke hoʻoheheʻe ʻia i ka wai wela. Paʻa kona hopena i ka mahana kiʻekiʻe me ka ʻole o ka gelling.
He kūpaʻa ia i nā waikawa a me nā kumu maʻamau. Hiki i nā Alkalis ke hoʻolalelale i kona hoʻoheheʻe ʻana a hoʻonui iki i kona mānoanoa. ʻOi aku ka ʻino o kona hiki ke hoʻoheheʻe ʻia i ka wai ma mua o ka methyl cellulose a me ka hydroxypropyl methyl cellulose.
ʻO ka Hydroxypropyl Methyl Cellulose (HPMC)
ʻO ke ʻano molekala o HPMC:
\[C6H7O2(OH)3-mn(OCH3)m,OCH2CH(OH)CH3\]n\]x
ʻO ka Hydroxypropyl methylcellulose kahi ʻano cellulose e piʻi wikiwiki nei ka hana a me ka hoʻohana ʻana.
He ʻetera hui ʻia me ka cellulose non-ionic i hana ʻia mai ka pulupulu i hoʻomaʻemaʻe ʻia ma hope o ka alkaliization, me ka hoʻohana ʻana i ka propylene oxide a me ka methyl chloride ma ke ʻano he etherification agent, ma o kahi moʻo o nā hopena. ʻO ke kekelē o ka hoʻololi ʻana ma ke ʻano maʻamau he 1.2 ~ 2.0.
He ʻokoʻa kona mau waiwai ma muli o nā lakio like ʻole o ka ʻike methoxyl a me ka ʻike hydroxypropyl.
He maʻalahi ka hoʻoheheʻe ʻana o ka Hydroxypropyl methylcellulose i ka wai anuanu, akā e pilikia ana ia i ka hoʻoheheʻe ʻana i ka wai wela. Akā, ʻoi aku ka kiʻekiʻe o kona mahana gelation i ka wai wela ma mua o ka methyl cellulose. Ua hoʻomaikaʻi nui ʻia ka solubility i ka wai anuanu i hoʻohālikelike ʻia me ka methyl cellulose.
Pili ka mānoanoa o ka hydroxypropyl methylcellulose i kona kaumaha molekala, a ʻo ka nui o ke kaumaha molekala, ʻo ke kiʻekiʻe o ka mānoanoa. Hoʻopilikia pū ka mahana i kona mānoanoa, i ka piʻi ʻana o ka mahana, e emi ana ka mānoanoa. Eia nō naʻe, ʻoi aku ka haʻahaʻa o ka hopena mahana o kona mānoanoa kiʻekiʻe ma mua o ka methyl cellulose. Paʻa kona hopena ke mālama ʻia ma ka mahana o ka lumi.
ʻO ka paʻa ʻana o ka wai o ka hydroxypropyl methylcellulose e pili ana i ka nui o kona hoʻohui ʻia, ka viscosity, a me nā mea ʻē aʻe, a ʻo kona helu paʻa wai ma ka nui hoʻohui like ʻoi aku ke kiʻekiʻe ma mua o ka methyl cellulose.
He paʻa ka Hydroxypropyl methylcellulose i ka waikawa a me ka alkali, a he paʻa loa kona hopena wai ma ka pae pH = 2 ~ 12. ʻAʻole nui ka hopena o ka soda caustic a me ka wai lime i kāna hana, akā hiki i ka alkali ke hoʻolalelale i kona hoʻoheheʻe ʻia a hoʻonui i kona mānoanoa.
He paʻa ka Hydroxypropyl methylcellulose i nā paʻakai maʻamau, akā inā kiʻekiʻe ka nui o ka wai paʻakai, e piʻi aʻe ana ka mānoanoa o ka wai hydroxypropyl methylcellulose.
Hiki ke kāwili ʻia ka Hydroxypropyl methylcellulose me nā hui polymer wai-hoʻoheheʻe ʻia e hana i kahi hopena like a kiʻekiʻe aʻe. E like me ka polyvinyl alcohol, starch ether, vegetable gum, a pēlā aku.
ʻOi aku ka maikaʻi o ke kūpaʻa ʻana o ka Hydroxypropyl methylcellulose i nā enzyme ma mua o ka methylcellulose, a ʻoi aku ka liʻiliʻi o ka hiki ke hoʻohaʻahaʻa ʻia kāna hopena e ka enzymatically ma mua o ka methylcellulose.
Ka manawa hoʻouna: Pepeluali-14-2023