Hydroxypropylmethylcellulose (HPMC) ndi chochokera ku cellulose chomwe chimagwiritsidwa ntchito kwambiri m'mafakitale osiyanasiyana. Ntchito zazikulu za HPMC ndi monga thickeners, stabilizers ndi emulsifiers mu chakudya, mankhwala ndi zodzikongoletsera mafakitale. HPMC imagwiritsidwanso ntchito pantchito yomanga ngati chowonjezera cha simenti, ngati zokutira mapiritsi ndi makapisozi, komanso ngati njira yothetsera maso. Zida zazikulu za HPMC ndi cellulose ndi reagents mankhwala.
Ma cellulose:
Cellulose ndiye chinthu chachikulu chopangira HPMC. Ma cellulose ndi polima wachilengedwe omwe amapezeka m'makoma a cell cell ndipo ndiye polima wachilengedwe wochuluka kwambiri padziko lapansi. The mankhwala zimatha mapadi ndi ofanana ndi HPMC, zomwe zimapangitsa kukhala abwino zopangira kupanga HPMC. Cellulose amachokera kuzinthu zosiyanasiyana, kuphatikizapo matabwa, thonje, ndi zomera zosiyanasiyana.
Magwero ambiri a cellulose omwe amagwiritsidwa ntchito popanga HPMC ndi zamkati zamatabwa. Mitengo yamitengo imachokera ku mitengo yofewa monga spruce, pine ndi fir. Zamkati zamatabwa zimayikidwa ndi mankhwala kuti ziphwanye lignin ndi hemicellulose, ndikusiya cellulose yoyera. Selulosi yoyerayo amatsukidwa ndikutsukidwa kuchotsa zonyansa zilizonse.
Ma cellulose omwe amagwiritsidwa ntchito popanga HPMC ayenera kukhala apamwamba kwambiri komanso njira zowongolera bwino ziyenera kutsatiridwa kuti zitsimikizire kuyera kwa cellulose. Kuyera kwa cellulose ndikofunikira chifukwa zonyansa zimatha kukhudza zomwe zimapangidwa pomaliza.
Chemical reagents:
Kupanga kwa HPMC kumafuna kugwiritsa ntchito mankhwala osiyanasiyana. Zomwe zimagwiritsidwa ntchito popanga HPMC zimaphatikizapo propylene oxide, methyl chloride, sodium hydroxide, hydrochloric acid, etc.
Propylene oxide imagwiritsidwa ntchito popanga hydroxypropyl cellulose (HPC), yomwe imasinthidwa ndi methyl chloride kupanga HPMC. HPC imakumana ndi methyl chloride kuti ilowe m'malo mwa magulu ena a hydroxyl pa tcheni cha cellulose ndi magulu a methoxy ndi hydroxypropyl, kupanga HPMC.
Sodium hydroxide imagwiritsidwa ntchito popanga HPMC kuonjezera pH phindu la yankho lomwe limathandizira kusungunula mapadi.
Pa HPMC kupanga ndondomeko, asidi hydrochloric ntchito kusintha pH phindu la yankho anachita.
Ma reagents a Chemical omwe amagwiritsidwa ntchito pakupanga kwa HPMC ayenera kukhala oyera kwambiri, ndipo zomwe zimachitika ziyenera kuyang'aniridwa mosamala kuti zitsimikizire mtundu wa chinthu chomaliza.
Pomaliza:
Zida zazikulu za HPMC ndi cellulose ndi reagents mankhwala. Cellulose, yochokera kuzinthu zosiyanasiyana kuphatikizapo nkhuni, thonje, ndi zomera zosiyanasiyana, ndizopangira zopangira HPMC. Mankhwala opangira mankhwala omwe amagwiritsidwa ntchito popanga HPMC ndi monga propylene oxide, methyl chloride, sodium hydroxide ndi hydrochloric acid. Kupanga kwa HPMC kumafuna njira zowongolera bwino kuti zitsimikizire chiyero cha zinthu zopangira komanso mtundu wa chinthu chomaliza. HPMC chimagwiritsidwa ntchito m'mafakitale osiyanasiyana ndipo ali osiyanasiyana ntchito chifukwa katundu wake wapadera.
Nthawi yotumiza: Sep-06-2023