He aha nā hopena o ka nui ʻala ma ka hydroxypropyl methylcellulose:
Hoʻohui ʻia ohydroxypropyl methylcellulose: E mālama pono i ka pulupulu cellulose me ka lye ma 35-40°C no ka hapalua hora, e kaomi, e wawahi i ka cellulose, a me ka makahiki pono ma 35°C, no laila, i ka awelika degere o ka polymerization o ka alkali i loaʻa i loko o ka pono laula i loko. E hoʻokomo i ka fiber alkali i loko o ka ipu etherification, e hoʻohui i ka propylene oxide a me ka methyl chloride i ke kaʻina, a etherify ma 50-80 ° C no 5 mau hola, ʻo ka nui o ke kaomi ma kahi o 1.8MPa. A laila e hoʻohui i kahi nui kūpono o ka waika hydrochloric a me ka waikawa oxalic i ka wai wela ma 90 ° C e holoi i ka mea e hoʻonui ai i ka leo. Dehydrate i loko o kahi centrifuge. Holoi me ka wai a hiki i ka pale. Ke emi ka wai o ka mea ma lalo o 60%, e hoʻomaloʻo me kahi kahe ea wela ma 130 ° C a hiki i ka haʻahaʻa o ka wai ma lalo o 5%.
ʻO ka HPMC i hana ʻia e ke ʻano solvent e hoʻohana i ka toluene a me ka isopropanol e like me nā solvents. Inā ʻaʻole maikaʻi ka holoi ʻana, e mau ana kekahi ʻala palupalu. I kēia manawa, ʻokoʻa loa ka maikaʻi o ka home hydroxypropyl methylcellulose HPMC, a ʻokoʻa ke kumukūʻai, e paʻakikī i nā mea kūʻai aku ke koho pono. ʻO kēia ka pilikia o ka holoi holoi, ʻaʻole ia e pili i ka hoʻohana ʻana a ʻaʻohe pilikia, ʻaʻole pono ka HPMC maʻemaʻe e honi i ka amonia, starch a me ka waiʻona; Ua moe koloheHPMChiki ke honi pinepine i nā ʻano ʻala a pau, ʻoiai ʻaʻole ʻono, kaumaha. Eia nō naʻe, ʻo ka hydroxypropyl methylcellulose i hana ʻia e nā mea hana he nui ke ʻala ikaika a me ka ʻala. ʻAʻole i kūpono ka maikaʻi.
Loaʻa ka Hypromellose ma ka hoʻoheheʻe ʻana i ka pulupulu hoʻomaʻemaʻe me ka wai liʻiliʻi e loaʻa ai ka cellulose alkaline, a laila hoʻohui i ka solvent, etherification agent, toluene, a me isopropanol no ka etherification reaction, neutralizing washing, drying, crushing, etc. ʻAe, e loaʻa kahi ʻala, no laila hiki i nā mea hoʻohana ke hoʻohana me ka hilinaʻi.
Ka manawa hoʻouna: Apr-25-2024