Cov tshuaj sib xyaw ua ke uas tsis tob, uas ua lub luag haujlwm tseem ceeb hauv kev txhim kho kev ua tau zoo ntawm cov tshuaj sib xyaw qhuav, suav txog ntau dua 40% ntawm cov nqi khoom siv hauv cov tshuaj sib xyaw qhuav. Feem ntau ntawm cov tshuaj sib xyaw hauv kev lag luam hauv tsev yog muab los ntawm cov tuam txhab txawv teb chaws, thiab cov khoom siv kuj yog muab los ntawm cov neeg muag khoom. Tus nqi ntawm cov khoom siv tshuaj sib xyaw qhuav tseem siab, thiab nws nyuaj rau kev ua kom nrov npe ntawm cov tshuaj masonry thiab plastering nrog ntau thiab ntau yam. Cov khoom lag luam siab kawg yog tswj hwm los ntawm cov tuam txhab txawv teb chaws, thiab cov tuam txhab tsim tshuaj sib xyaw qhuav muaj cov txiaj ntsig qis thiab tus nqi tsis zoo; kev siv cov tshuaj sib xyaw tsis muaj kev tshawb fawb thiab tsom mus rau, thiab ua raws li cov qauv txawv teb chaws. Ntawm no, qhov peb qhia rau koj yog, lub luag haujlwm ntawm hydroxypropyl methylcellulose hauv cov tshuaj sib xyaw ntawm cov tshuaj sib xyaw qhuav yog dab tsi?
Hydroxypropyl methylcellulose yog ib hom cellulose uas nws cov zis thiab kev noj tau nce sai sai hauv xyoo tas los no. Hydroxypropyl methylcellulose yog ua los ntawm paj rwb zoo tom qab kev kho alkalization, siv propylene oxide thiab methyl chloride ua cov neeg sawv cev etherification, ib qho non-ionic cellulose sib xyaw ether ua los ntawm ntau yam kev tshuaj tiv thaiv. Qhov degree ntawm kev hloov pauv feem ntau yog 1.2 ~ 2.0. Nws cov khoom sib txawv nyob ntawm qhov piv ntawm methoxyl cov ntsiab lus thiab hydroxypropyl cov ntsiab lus. Cov yam ntxwv ntawm hydroxypropyl methylcellulose yog raws li nram no:
1. Hydroxypropyl methylcellulose yooj yim yaj hauv dej txias, thiab nws yuav ntsib teeb meem hauv kev yaj hauv dej kub. Tab sis nws qhov kub gelation hauv dej kub siab dua li ntawm methyl cellulose. Qhov solubility hauv dej txias kuj zoo dua piv rau methyl cellulose.
2. Qhov viscosity ntawm hydroxypropyl methylcellulose muaj feem cuam tshuam nrog nws qhov hnyav molecular. Qhov loj dua qhov hnyav molecular, qhov siab dua qhov viscosity. Kub kuj cuam tshuam rau nws qhov viscosity, thaum kub nce, viscosity txo qis. Txawm li cas los xij, qhov cuam tshuam ntawm nws qhov viscosity siab thiab kub qis dua li ntawm methyl cellulose. Nws cov kua ruaj khov thaum khaws cia rau hauv chav tsev kub.
3. Qhov khaws dej ntawm hydroxypropyl methylcellulose nyob ntawm nws qhov ntxiv, viscosity, thiab lwm yam, thiab nws qhov khaws dej hauv qab tib qhov ntxiv yog siab dua li ntawm methyl cellulose.
4. Hydroxypropyl methylcellulose ruaj khov rau cov kua qaub thiab alkali, thiab nws cov kua dej ruaj khov heev hauv pH = 2 ~ 12. Caustic soda thiab dej txiv qaub tsis muaj feem cuam tshuam rau nws cov kev ua tau zoo, tab sis alkali tuaj yeem ua kom nws cov yaj sai dua thiab ua rau nws cov viscosity me ntsis. Hydroxypropyl methylcellulose ruaj khov rau cov ntsev feem ntau, tab sis thaum cov ntsev concentration siab, cov viscosity ntawm hydroxypropyl methylcellulose kua feem ntau nce.
5. Hydroxypropyl methylcellulose tuaj yeem sib xyaw nrog cov polymers uas yaj tau hauv dej los ua cov tshuaj sib xyaw thiab viscosity siab dua. Xws li polyvinyl cawv, starch ether, zaub gum, thiab lwm yam.
6. Hydroxypropyl methylcellulose muaj kev tiv thaiv enzyme zoo dua li methylcellulose, thiab qhov ua tau ntawm enzymatic degradation ntawm nws cov tshuaj yog qis dua li ntawm methylcellulose.
7. Qhov kev nplaum ntawm hydroxypropyl methylcellulose rau kev tsim kho mortar siab dua li ntawm methylcellulose.
Lub sijhawm tshaj tawm: Tsib Hlis-09-2023