Ko kunhuwa kwehydroxypropyl methylcellulose kunokanganisa sei kunaka?

Ndeipi mhedzisiro yekunhuhwirira saizi pahydroxypropyl methylcellulose:

Synthesis ofhydroxypropyl methylcellulose: Bata yakanatswa cotton cellulose nelye pa 35-40 ° C kwehafu yeawa, dzvanya, pwanya cellulose, uye zera zvakakodzera pa 35 ° C, kuitira kuti avhareji yedhigirii yepolymerization yeakawanikwa alkali iri mukati memhando inodiwa fibers mukati. Isa iyo alkali fiber mu kettle ye etherification, wedzera propylene oxide uye methyl chloride munhevedzano, uye etherify pa50-80 ° C kwemaawa mashanu, iyo yakanyanya kudzvanywa inenge 1.8MPa. Zvadaro wobva wawedzera huwandu hwakakodzera hwehydrochloric acid uye oxalic acid kumvura inopisa pa90 ° C kuti usuke zvinhu kuti uwedzere huwandu. Dehydrate mu centrifuge. Shamba nemvura kusvikira usina kwaunotsigira. Kana hunyoro hwezvinhu hwadzikira kudarika 60%, huomesa nemhepo inopisa pa130°C kusvikira hunyoro hwadzika kudarika 5%.

Iyo HPMC inogadzirwa nenzira yekunyungudutsa inoshandisa toluene uye isopropanol sezvinonyungudutsa. Kana kushambidzika kusina kunaka, kumwe kunhuhwirira kunoramba kuripo. Parizvino, mhando yemumba hydroxypropyl methylcellulose HPMC inosiyana zvakanyanya, uye mutengo unosiyana zvakanyanya, zvichiita kuti zviomere vatengi kuita sarudzo chaiyo. Iri ndiro dambudziko rekugeza, harina kukanganisa kushandiswa uye hapana dambudziko, yakachena HPMC haifaniri kunhuwa ammonia, starch uye doro; AdlteratedHPMCinogona kazhinji kunhuhwirira kwemarudzi ose, kunyange kana isina kunaka, inonzwa ichirema. Nekudaro, iyo hydroxypropyl methylcellulose inogadzirwa nevazhinji vagadziri ine kunhuhwirira kwakasimba uye kunhuhwirira. Hunhu hwacho zvechokwadi hauna kusvika padanho.

Hypromellose inowanikwa nekupfekedza donje rakanatswa nemvura isingawanzo kuwana alkaline cellulose, wobva wawedzera solvent, etherification agent, toluene, uye isopropanol ye etherification reaction, neutralizing washing, kuomesa, kupwanya, nezvimwewo kuti uwane zvigadzirwa zvapera. Zvakanaka, pachava nekunhuhwirira, saka vashandisi vanogona kuishandisa nechivimbo.