Kev ntub dej tshwm sim thaum cov khoom khov kov cov kua. Cov khoom khov-roj thiab kua-roj sib tshuam qub ploj mus, thiab cov khoom khov-kua sib tshuam tshiab tau tsim. Piv txwv li, cov ntaub fibers yog cov khoom siv porous nrog thaj chaw loj. Thaum cov tshuaj kis mus rau ntawm cov fibers, nws nkag mus rau hauv qhov sib txawv ntawm cov fibers thiab hloov chaw huab cua, tig qhov sib tshuam cua-fiber qub mus rau hauv qhov sib tshuam kua-fiber.—qhov no yog ib qho txheej txheem ntub dej ib txwm muaj. Lub caij no, cov tshuaj nkag mus rau hauv sab hauv ntawm cov fibers, ib qho txheej txheem hu ua kev nkag mus. Cov tshuaj surfactants uas pab txhawb kev ntub dej thiab kev nkag mus hu ua cov neeg sawv cev ntub dej thiab cov neeg sawv cev nkag mus.
Cov roj muaj qhov nro ntawm qhov chaw siab hauv dej. Thaum ntxiv roj rau hauv dej thiab cov khoom sib tov raug do kom zoo, cov roj tawg ua cov tee me me los ua cov emulsion, tab sis cov khoom sib tov yuav sib cais ua cov txheej dua thaum tsis txhob do. Yog tias ntxiv cov surfactant thiab cov khoom sib tov raug do, cov txheej yuav tsis sib cais yooj yim rau lub sijhawm ntev tom qab tsis txhob do, uas yog emulsification. Qhov hydrophobic ntawm cov roj molecules yog nyob ib puag ncig los ntawm cov hydrophilic pawg ntawm surfactants, tsim cov zog nyiam kev taw qhia. Qhov no txo cov zog uas xav tau los faib cov roj hauv dej thiab ua tiav cov emulsification zoo ntawm cov roj.
Ua tsaug rau qhov ua kom emulsifying ntawm surfactants, cov roj thiab cov av uas raug rho tawm ntawm cov chaw khov kho tuaj yeem emulsified thiab dispersed hauv cov kua dej, tiv thaiv lawv los ntawm kev rov tso rau ntawm cov chaw ntxuav thiab ua rau rov ua qias tuaj.
Kev tawg yog hais txog cov txheej txheem uas cov khoom khov uas tsis yaj tau raug faib ua cov khoom me me hauv cov tshuaj kom tsim tau cov tshuaj suspension. Cov surfactants uas ua kom cov khoom khov tawg thiab tswj cov tshuaj suspensions ruaj khov hu ua dispersants. Hauv kev xyaum, nws nyuaj rau qhov txawv ntawm emulsification thiab dispersion thaum cov roj semi-solid raug emulsified thiab dispersed hauv cov tshuaj. Vim tias emulsifiers thiab dispersants feem ntau yog tib hom tshuaj, lawv raug hu ua emulsifier-dispersants hauv kev siv tiag tiag.
Kev yaj txhais tau hais tias cov surfactants tuaj yeem ua rau kom muaj kev yaj ntawm cov tshuaj uas yaj tau me ntsis lossis cov tshuaj uas tsis yaj hauv dej. Piv txwv li, qhov kev yaj ntawm benzene hauv dej yog 0.09% los ntawm qhov ntim. Tom qab ntxiv cov surfactants xws li sodium oleate, qhov kev yaj ntawm benzene tuaj yeem nce mus txog 10%.
Kev yaj yog qhov sib txuas ze rau cov micelles uas tsim los ntawm surfactants hauv dej. Ib qho micelle yog cov khoom sib xyaw ua ke uas tsim thaum cov saw hydrocarbon ntawm cov surfactant molecules kos ze rau ib leeg hauv cov kua dej vim yog kev sib cuam tshuam hydrophobic. Sab hauv ntawm ib qho micelle yog cov kua hydrocarbons, yog li cov organic solutes uas tsis yog polar uas tsis yaj hauv dej, xws li benzene thiab cov roj av, tuaj yeem yaj tau yooj yim hauv micelles. Kev yaj yog kev yaj ntawm cov tshuaj lipophilic los ntawm micelles, ib qho khoom tshwj xeeb ntawm surfactants. Nws tsuas yog siv tau thaum qhov concentration surfactant hauv cov kua ntau dua qhov concentration micelle tseem ceeb (CMC), uas yog thaum muaj ntau tus micelles loj. Tsis tas li ntawd, cov micelles loj dua muab peev xwm yaj tau ntau dua.
Kev yaj sib txawv ntawm kev emulsification. Emulsification tsim ib lub kaw lus multiphase tsis sib txuas thiab tsis ruaj khov uas ib theem kua tau tawg hauv dej lossis lwm theem kua. Qhov sib txawv, kev yaj ua rau muaj ib lub kaw lus ib theem uas sib xws, ruaj khov uas cov tshuaj yaj thiab cov tshuaj yaj muaj nyob hauv tib theem. Ib hom surfactant yuav muaj ob qho tib si emulsifying thiab solubilizing, tab sis kev yaj tsuas yog tshwm sim thaum nws qhov concentration siab dua qhov tseem ceeb ntawm micelle.
Thaum cov tshuaj surfactant sib dhos ua ke rau ntawm cov ntaub, lawv txo qhov coefficient ntawm kev sib txhuam zoo li qub ntawm cov ntaub. Cov tshuaj surfactants tsis yog ionic xws li linear alkyl polyoxyethylene polyols thiab linear alkyl fatty acid polyoxyethylene ethers, nrog rau ntau yam cationic surfactants, tuaj yeem txo qhov coefficient ntawm kev sib txhuam zoo li qub ntawm cov ntaub thiab yog li ua haujlwm ua cov tshuaj ua kom ntaub mos. Txawm li cas los xij, cov tshuaj surfactants nrog cov pab pawg alkyl lossis aromatic tsis ua tiav kev teeb tsa kev coj ua zoo ntawm cov ntaub thiab yog li ntawd tsis haum rau kev siv ua cov tshuaj ua kom ntaub mos.
Lub sijhawm tshaj tawm: Lub Rau Hli-10-2026