Methylcellulose (MC)
ʻO ke kumu molekala o ka methylcellulose (MC):
[C6H7O2(OH)3-h(OCH3)n\]x
ʻO ke kaʻina hana e hana i ka cellulose ether ma o ke ʻano o nā hopena ma hope o ka mālama ʻia ʻana o ka pulupulu hoʻomaʻemaʻe me ka alkali, a hoʻohana ʻia ka methyl 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.
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.
ʻO ka paʻa ʻana o ka wai o ka methylcellulose 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.
Carboxymethylcellulose (CMC)
ʻO Carboxymethyl cellulose, ʻike ʻia hoʻi ʻo ka sodium carboxymethyl cellulose, i ʻike mau ʻia he cellulose, cmc, etc., he anionic linear polymer, he paʻakai sodium o cellulose carboxylate, a he mea hou a pau ʻole.Nā mea maka kemika.
Hoʻohana nui ʻia ia i ka ʻoihana detergent, ʻoihana meaʻai a me ka wai hoʻoheheʻe ʻaila ʻaila, a ʻo ka nui i hoʻohana ʻia i nā mea hoʻonaninani wale nō ma kahi o 1%.
Hana ʻia ʻo Ionic cellulose ether mai nā fiber maoli (ka pulupulu, a me nā mea ʻē aʻe) 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 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.
Loaʻa iā CMC ka hiki ke hoʻopaʻa paʻa maikaʻi, a he maikaʻi kona hoʻonā wai, akā ʻaʻohe waiwai deformation plastik maoli.
Ke hemo ka CMC, hiki maoli ka depolymerization.Hoʻomaka ka viscosity e piʻi i ka wā o ka hoʻoheheʻe ʻana, hele i kahi kiʻekiʻe, a laila hāʻule i kahi pāpū.Ua pili ka viscosity i ka depolymerization.
ʻO ke kūlana o ka depolymerization e pili kokoke ana i ka nui o ka mea hoʻoheheʻe maikaʻi ʻole (wai) i ka hana.Ma kahi ʻōnaehana hoʻoheheʻe maikaʻi ʻole, e like me ka toothpaste i loaʻa ka glycerin a me ka wai, ʻaʻole e hoʻopau loa ʻo CMC a hiki i kahi helu kaulike.
I ka hihia o ka wai i hāʻawi ʻia, ʻoi aku ka maʻalahi o ka CMC i hoʻololi nui ʻia i ka hydrophilic ma mua o ka CMC i pani haʻahaʻa.
Hydroxyethylcellulose (HEC)
Hana ʻia ʻo HEC ma o 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 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.
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.
Paʻa ia i nā ʻakika a me nā kumu maʻamau.Hiki i ka Alkalis ke hoʻonui i kona viscosity.ʻOi aku ka ʻino o kona hoʻopuehu ʻana i ka wai ma mua o ka methyl cellulose a me ka hydroxypropyl methyl cellulose.
Hydroxypropyl Methyl Cellulose (HPMC)
ʻO ke kumu molekula o HPMC:
\[C6H7O2(OH)3-mn(OCH3)m,OCH2CH(OH)CH3\]n\]x
ʻO ka Hydroxypropyl methylcellulose kahi ʻano cellulose e piʻi wikiwiki ana ka hoʻopuka a me ka hoʻohana ʻana.
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.
ʻOkoʻa kona mau waiwai ma muli o nā ratio like ʻole o ka methoxyl content a me ka hydroxypropyl content.
Hiki ke hoʻoheheʻe ʻia ka Hydroxypropyl methylcellulose i loko o ka wai anuanu, akā paʻakikī 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.
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.
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 ka huina like ma mua o ka methyl cellulose.
ʻO ka Hydroxypropyl methylcellulose paʻa i ka waikawa a me ka alkali, a paʻa loa kona ʻano wai i ka pae o ka pH = 2 ~ 12.ʻAʻole 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.
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 nui o ka viscosity solution.E like me ka waiʻona polyvinyl, starch ether, mea ʻai meaʻai, etc.
ʻOi aku ka maikaʻi o ke kūpaʻa ʻana o ka enzyme hydroxypropyl methylcellulose ma mua o ka methylcellulose, a ʻoi aku ka liʻiliʻi o kāna hopena i ka enzymatically degraded ma mua o ka methylcellulose.
Ka manawa hoʻouna: Feb-14-2023