Hydroxypropylmethylcellulose (HPMC) tau txais kev nyiam hauv kev lag luam kev tsim kho vim nws cov khoom zoo heev uas khaws dej tau zoo. HPMC yog cov cellulose ether uas tsis yog ionic, yaj tau hauv dej, uas siv dav hauv ntau yam lag luam. Hauv kev tsim kho, nws feem ntau yog siv los ua cov khoom ua kom tuab, cov khoom sib txuas thiab cov khoom khaws dej hauv cov ntaub ntawv cement thiab cov mortars. Qhov zoo ntawm HPMC kuj muaj qee qhov cuam tshuam rau nws cov kev ua tau zoo ntawm kev khaws dej, uas peb yuav tshawb nrhiav hauv tsab xov xwm no.
Ua ntej, nws yog ib qho tseem ceeb kom nkag siab tias HPMC yog dab tsi thiab nws ua haujlwm li cas. HPMC yog ib qho derivative ntawm cellulose, ib qho polymer ntuj tsim los ntawm ntoo thiab cov nroj tsuag fibers. HPMC yog tsim los ntawm kev hloov kho cellulose nrog propylene oxide thiab methyl chloride, uas ntxiv hydroxypropyl thiab methyl pawg rau hauv cellulose molecule. Cov kev hloov kho no ua rau HPMC yaj ntau dua hauv dej thiab muab nws cov khoom tshwj xeeb xws li thickening, emulsification thiab dej khaws cia.
Cov yam ntxwv ntawm HPMC uas khaws dej tau zoo yog qhov tseem ceeb heev hauv kev lag luam kev tsim kho, qhov twg kev tswj dej noo yog qhov tseem ceeb. Thaum HPMC raug ntxiv rau cov khoom siv cementitious lossis mortar, nws tsim ib daim zaj duab xis nyob ib puag ncig cov khoom cement, txo cov dej nkag mus. Daim zaj duab xis kuj pab qeeb qeeb qhov evaporation ntawm cov dej los ntawm qhov sib tov, muab sijhawm ntau dua rau cov cement kom hydrate. Yog li ntawd, cov khoom siv cementitious thiab mortars tseem ntub rau lub sijhawm ntev dua, ua rau lawv kho tau zoo thiab ua tiav lub zog siab tshaj plaws.
Qhov zoo ntawm HPMC ua lub luag haujlwm tseem ceeb hauv nws txoj kev ua haujlwm khaws dej. Feem ntau hais lus, cov khoom me me ntawm HPMC, qhov zoo dua qhov muaj peev xwm khaws dej. Qhov no yog vim tias cov khoom me me muaj thaj chaw loj dua, uas tso cai rau lawv tsim cov zaj duab xis dav dua nyob ib puag ncig cov khoom me me ntawm cement. Cov zaj duab xis pab tsim ib qho kev thaiv ntawm cov cement thiab dej, qeeb qeeb qhov nkag mus rau hauv qhov sib tov. Yog li ntawd, qhov sib tov nyob ntub ntev dua, muab sijhawm ntau dua rau cov cement kom hydrate thiab cov mortar kom kho.
Tab sis nws tsim nyog sau tseg tias qhov zoo ntawm HPMC yuav tsum tsis txhob yog qhov xav txog thaum xaiv tus neeg sawv cev khaws dej. Lwm yam xws li hom cement, qhov sib piv ntawm dej-cement, qhov kub thiab txias thiab av noo kuj cuam tshuam rau cov khoom khaws dej ntawm HPMC. Yog li ntawd, nws yog ib qho tseem ceeb uas yuav tsum xaiv cov khoom HPMC uas haum rau daim ntawv thov thiab siv ib puag ncig.
Hauv kev xaus lus, muaj ntau qhov zoo ntawm kev siv HPMC ua tus neeg sawv cev khaws dej hauv cov ntaub ntawv cementitious thiab mortars. Nws cov khoom khaws dej ua kom ntseeg tau tias cov khoom sib xyaw tseem ntub ntev dua, muab sijhawm ntau dua rau cov cement kom hydrate thiab cov mortar kom kho. Qhov zoo ntawm HPMC yog ib qho tseem ceeb uas cuam tshuam rau nws lub peev xwm khaws dej, qhov zoo dua cov khoom me me, qhov zoo dua qhov kev ua tau zoo. Txawm li cas los xij, lwm yam xws li hom cement, dej-cement piv, kub thiab av noo kuj yuav tsum tau xav txog thaum xaiv cov khoom HPMC. Zuag qhia tag nrho, kev siv HPMC yog ib txoj hauv kev zoo heev los txhim kho kev ua tau zoo thiab lub neej ntev ntawm cov ntaub ntawv cementitious thiab mortars hauv kev lag luam kev tsim kho.
Lub sijhawm tshaj tawm: Lub Yim Hli-16-2023