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HPMC no ka uhi kiʻiʻoniʻoni

HPMC no ka uhi kiʻiʻoniʻoni

HPMC noʻO ka uhi kiʻiʻoniʻoni ke ʻano o ka hana ʻana i kahi kiʻiʻoniʻoni lahilahi o kahi polymer ma luna o kahi hoʻomākaukau paʻa. No ka laʻana, hoʻoheheʻe ʻia kahi papa o nā mea polymer kūpaʻa ma luna o ka ʻili o ka pepa maʻemaʻe ma ke ʻano o ka pulupulu ʻana e hana i kahi papa kiʻiʻoniʻoni plastik mau microns mānoanoa, i hiki ai ke hoʻokō i ka hopena i makemake ʻia. ʻO ka hoʻokumu ʻia ʻana o kēia ʻāpana kiʻiʻoniʻoni ma waho o ka pākaukau ʻo ia ka pili ʻana o kahi papa hoʻokahi i ka mea uhi polymer ma hope o ka hele ʻana i loko o ka wahi e hoʻopuʻi ai, a laila loaʻa ka ʻāpana aʻe o ka mea uhi ma hope o ka maloʻo ʻana. Ma hope o ka hoʻopili pinepine ʻana a me ka hoʻomaloʻo ʻana, hoʻopau ʻia ka uhi a hiki i ka uhi ʻana o ka ʻili holoʻokoʻa o ka hoʻomākaukau. ʻO ka uhi kiʻiʻoniʻoni he kiʻiʻoniʻoni mau, mānoanoa ka nui ma waena o 8 a 100 microns, kahi pae o ka elasticity a me ka maʻalahi, pili paʻa i ka ʻili o ke kumu.

I ka makahiki 1954, ua hana ʻo Abbott i ka pūʻulu mua o nā pepa kiʻiʻoniʻoni i loaʻa i ke kālepa, mai ia manawa, me ka hoʻomaikaʻi mau ʻana a me ka maikaʻi o nā lako hana a me nā ʻenehana, ua hoʻokuʻu ʻia nā mea kiʻiʻoniʻoni polymer, no laila ua hoʻomohala wikiwiki ʻia ka ʻenehana uhi kiʻiʻoniʻoni. ʻAʻole wale ka nui, ka nui a me ka maikaʻi o nā mea hoʻonaninani kala i hoʻonui wikiwiki ʻia, akā ua hoʻomohala nui ʻia nā ʻano, nā ʻano a me nā hiʻohiʻona o ka ʻenehana uhi, nā mea hoʻonaninani a me nā kiʻi ʻoniʻoni a me ka hoʻopili ʻana o nā pil TCM. No laila, ua lilo ka noi o ka ʻenehana uhi kiʻiʻoniʻoni i mea pono a me ka ulu ʻana o nā ʻoihana lāʻau lapaʻau e hoʻomaikaʻi i ka maikaʻi o ka huahana.

Hoʻohana mua ʻia i nā mea hana kiʻiʻoniʻoni kiʻiʻoniʻoni, aia nō ka nui o nā huahana e hoʻohana ana i ka HPMChydroxypropyl methylcellulosee like me nā mea Membrane. ʻO ia ka hoʻomaʻemaʻeHPMCcellulose mai ka pulupulu lint a me ka laau pulp, a me ka sodium hydroxide solution e hoike mai i ka pehu ana o ka alkali cellulose, a me ka chloromethane a me ka propylene oxide lapaau e loaa ai ka methyl hydroxypropyl cellulose ether.HPMC, ka huahana e wehe i nā haumia ma hope o ka maloʻo ʻana, ka ʻoki ʻana, ka paʻi. ʻO ka maʻamau, hoʻohana ʻia ka HPMC viscosity haʻahaʻa e like mekiʻiʻoniʻonimea hoʻopili, a ʻo 2% ~ 10% ka hopena i hoʻohana ʻia e like me ka hoʻonā ʻana. ʻO ka hemahema ʻo ia ka nui o ka viscosity a ʻoi aku ka ikaika o ka hoʻonui.

ʻO ka lua o ka hanauna o nā mea hana kiʻiʻoniʻoni he polyvinyl alcohol (PVA). Hoʻokumu ʻia ka waiʻona polyvinyl e ka alcoholysis o ka polyvinyl acetate. ʻAʻole hiki ke hoʻohana ʻia nā ʻāpana wai inu Vinyl e like me nā reactants no ka mea ʻaʻole lākou e hoʻokō i ka nui a me ka maʻemaʻe e pono ai no ka polymerization. I loko o ka methanol, ethanol a i ʻole ethanol a me ka methyl acetate i hui pū ʻia me ka metala alkali a i ʻole ka waikawa inorganic e like me ka catalyst, wikiwiki ka hydrolysis.

Hoʻohana nui ʻia ka PVA i ka uhi kiʻiʻoniʻoni. No ka mea, ʻaʻole hiki ke hoʻoheheʻe ʻia i ka wai ma ke ana wela, ua uhi ʻia me ka 20% o ka hoʻopuehu wai. ʻOi aku ka haʻahaʻa o ka wai wai a me ka oxygen permeability o PVA ma mua o HPMC a me EC, no laila ʻoi aku ka ikaika o ka pale ʻana o ka wai a me ka oxygen, hiki ke pale maikaʻi i ke kumu chip.

ʻO ka Plasticizer e pili ana i kahi mea hiki ke hoʻonui i ka plasticity o nā mea hana kiʻiʻoniʻoni. Ke hoʻololi nei kekahi mau mea hana kiʻiʻoniʻoni i ko lākou mau waiwai kino ma hope o ka emi ʻana o ka mahana, a liʻiliʻi ka neʻe ʻana o kā lākou macromolecules, e hana ana i ka paʻakikī a me ka brittle, nele i ka pono kūpono, a no laila maʻalahi ka haki. Hoʻohui ʻia ka Plasticizer e hōʻemi i ka mahana hoʻololi aniani (Tg) a hoʻonui i ka maʻalahi o ka uhi. ʻO nā mea plasticizer maʻamau he polymers amorphous me ke kaumaha molekala nui a me ka pilina ikaika me nā mea hana kiʻiʻoniʻoni. ʻO ka plasticizer insoluble e kōkua i ka hōʻemi i ka permeability o ka uhi, no laila e hoʻonui ai i ka paʻa o ka hoʻomākaukau.

 

Manaʻo ʻia ʻo ke ʻano o ka plasticizer ka mea i hoʻokomo ʻia nā molekole plasticizer i loko o ke kaulahao polymer, kahi e ālai ai i ka pilina ma waena o nā molekala polymer i kahi nui. ʻOi aku ka maʻalahi o ka pilina inā ʻoi aku ka ikaika o ka pilina polymer-plasticizer ma mua o ka pilina polymer-plasticizer. No laila, hoʻonui ʻia nā manawa kūpono e neʻe ai nā ʻāpana polymer.

ʻO ke kolu o ka hanauna o nā mea hana kiʻiʻoniʻoni ʻo ia ka plasticizer ma ke ʻano kemika i kālai ʻia i loko o ka kiʻiʻoniʻoni e hana ana i nā mea polymer.

No ka laʻana, ʻO ka mea hana kiʻiʻoniʻoni hou ʻo Kollicoat® IR i hoʻokomo ʻia e BASF ʻo ia ka PEG i hoʻopili kemika i ke kaulahao lōʻihi o PVA polymer me ka hoʻohui ʻole ʻana i ka plasticizer, no laila hiki iā ia ke pale i ka neʻe ʻana o ka loko ma hope o ka uhi ʻana.


Ka manawa hoʻouna: Dec-23-2023
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