Kunyowetsa, chofunikira: HLB: 7-9
Kunyowetsa kumatanthauzidwa ngati chochitika chomwe mpweya womwe umalowa pamwamba pa chinthu cholimba umasunthidwa ndi madzi. Zinthu zomwe zingawonjezere mphamvu yosunthika iyi zimatchedwa zinthu zonyowetsa. Kunyowetsa nthawi zambiri kumagawidwa m'magulu atatu: kunyowetsa kolumikizana (kunyowetsa komatira), kunyowetsa kothira (kunyowetsa kothira), ndi kunyowetsa kothira (kufalikira). Pakati pa izi, kufalikira kumayimira muyezo wapamwamba kwambiri wa kunyowetsa, ndipo coefficient yofalikira nthawi zambiri imagwiritsidwa ntchito ngati chizindikiro chowunikira momwe kunyowetsa kumagwirira ntchito pakati pa machitidwe osiyanasiyana. Kuphatikiza apo, ngodya yolumikizirana nayonso ndi muyezo wowunikira mtundu wa kunyowetsa. Zinthu zopopera zitha kugwiritsidwa ntchito kuwongolera kuchuluka kwa kunyowetsa pakati pa magawo amadzimadzi ndi olimba.
Mu makampani opanga mankhwala ophera tizilombo, mankhwala ena opangidwa ndi granular ndi ufa wofumbi amakhala ndi mankhwala enaake ophera tizilombo. Cholinga chawo ndikuwongolera kumamatira ndi kuchuluka kwa mankhwala ophera tizilombo pamalo omwe akufunidwa, kufulumizitsa kuchuluka kwa kutulutsa mankhwala ndikukulitsa malo ofalikira a zosakaniza zomwe zimagwira ntchito m'malo onyowa, motero kukulitsa mphamvu yopewera matenda ndi kuchiza.
Mu makampani opanga zodzoladzola, ma surfactants amagwira ntchito ngati ma emulsifiers ndipo ndi zinthu zofunika kwambiri mu zinthu zosamalira khungu monga mafuta, mafuta odzola, zotsukira nkhope ndi zochotsa zodzoladzola.
Micelles ndi Solubilization,zofunikira: C > CMC (HLB 13–18)
Kuchuluka kochepa komwe mamolekyu a surfactant amalumikizana nako kuti apange ma micelles. Pamene kuchuluka kwa mamolekyu a surfactant kupitirira CMC value, mamolekyu a surfactant amapangidwa okha m'mapangidwe monga mawonekedwe ozungulira, ofanana ndi ndodo, lamellar, kapena ofanana ndi mbale.
Machitidwe osungunula ndi machitidwe olinganiza a thermodynamic. CMC ikatsika komanso kuchuluka kwa mgwirizano, kuchuluka kwa maximum additive concentration (MAC) kumakhala kwakukulu. Zotsatira za kutentha pa kusungunuka kwa madzi zimaonekera m'mbali zitatu: zimakhudza mapangidwe a micelle, kusungunuka kwa madzi osungunuka, ndi kusungunuka kwa madzi osungunuka okha. Kwa ma ionic surfactants, kusungunuka kwawo kumawonjezeka kwambiri kutentha kukakwera, ndipo kutentha komwe kumabwera mwadzidzidzi kumatchedwa Krafft point. Malo a Krafft akakwera, kuchuluka kwa madzi ofunikira kumachepa.
Kwa ma surfactants a polyoxyethylene nonionic, kutentha kukakwera kufika pamlingo winawake, kusungunuka kwawo kumatsika kwambiri ndipo mvula imayamba kugwa, zomwe zimapangitsa kuti yankho likhale lopanda madzi. Chochitikachi chimadziwika kuti clouding, ndipo kutentha kofanana kumatchedwa cloud point. Kwa ma surfactants omwe ali ndi utali wofanana wa unyolo wa polyoxyethylene, unyolo wa hydrocarbon ukakhala wautali, unyolo wa cloud umatsika; mosiyana, ndi utali wofanana wa unyolo wa hydrocarbon, unyolo wa polyoxyethylene ukakhala wautali, unyolo wa cloud umakwera.
Zinthu zopanda polar organic (monga benzene) zimakhala ndi kusungunuka kochepa kwambiri m'madzi. Komabe, kuwonjezera ma surfactants monga sodium oleate kungathandize kwambiri kusungunuka kwa benzene m'madzi—njira yotchedwa kusungunuka. Kusungunuka kumasiyana ndi kusungunuka wamba: benzene yosungunuka siimafalikira mofanana m'mamolekyu amadzi koma imatsekeredwa mkati mwa micelles yopangidwa ndi ma ayoni a oleate. Kafukufuku wa X-ray diffraction watsimikizira kuti mitundu yonse ya micelles imakula mpaka madigiri osiyanasiyana pambuyo pa kusungunuka, pomwe mphamvu za colligative za yankho lonse sizisintha kwenikweni.
Pamene kuchuluka kwa ma surfactants m'madzi kukuchulukirachulukira, mamolekyu a surfactant amasonkhana pamwamba pa madzi kuti apange gawo lozungulira komanso lolunjika bwino. Mamolekyu ochulukirapo mu gawo lalikulu amasonkhana pamodzi ndi magulu awo osagwirizana ndi madzi omwe akuyang'ana mkati, ndikupanga ma micelles. Kuchuluka kochepa komwe kumafunika kuti ayambe kupanga ma micelle kumatanthauzidwa ngati kuchuluka kwa micelle kofunikira (CMC). Pa kuchuluka kumeneku, yankho limasiyana ndi khalidwe labwino, ndipo malo osiyana a inflection amawonekera pa kukanika kwa pamwamba poyerekeza ndi kuzungulira kwa kuchuluka. Kuonjezera kuchuluka kwa surfactant sikudzachepetsanso kukanika kwa pamwamba; m'malo mwake, kudzalimbikitsa kukula kosalekeza ndi kuchulukitsa kwa ma micelles mu gawo lalikulu.
Pamene mamolekyu a surfactant amwazikana mu yankho ndikufika pamlingo winawake wa kuchuluka, amalumikizana kuchokera ku ma monomers (ma ion kapena ma molecule) kukhala ma colloidal aggregates otchedwa micelles. Kusinthaku kumayambitsa kusintha kwadzidzidzi kwa mphamvu zakuthupi ndi zamakemikolo a yankho, ndipo kuchuluka komwe izi zimachitika ndi CMC. Njira yopangira micelle imatchedwa micellization.
Kupangidwa kwa ma micelles mu njira zamadzimadzi za surfactant kumadalira kuchuluka kwa madzi. Mu njira zochepetsera madzi kwambiri, madzi ndi mpweya zimakhudzana mwachindunji, kotero mphamvu ya pamwamba imachepa pang'ono, kukhala pafupi ndi madzi oyera, ndi mamolekyu ochepa kwambiri a surfactant omwe amafalikira mu gawo lalikulu. Pamene kuchuluka kwa surfactant kumawonjezeka pang'ono, mamolekyu amalowa mwachangu pamwamba pa madzi, kuchepetsa malo olumikizirana pakati pa madzi ndi mpweya ndikupangitsa kuti mphamvu ya pamwamba igwe kwambiri. Pakadali pano, mamolekyu ena a surfactant mu gawo lalikulu amasonkhana pamodzi ndi magulu awo osagwirizana ndi madzi, ndikupanga ma micelles ang'onoang'ono.
Pamene kuchuluka kwa madzi kukupitirira kukwera ndipo yankho likufikira pakukhuta kwa madzi, filimu yodzaza ndi mamolekyulu imapangidwa pamwamba pa madzi. Pamene kuchuluka kwa madzi kukufikira pa CMC, mphamvu ya pamwamba ya yankho imafika pamtengo wake wocheperako. Kupitirira CMC, kuonjezera mphamvu ya madzi a surfactant sikukhudza mphamvu ya pamwamba; m'malo mwake, kumawonjezera chiwerengero ndi kukula kwa ma micelles mu gawo lalikulu. Kenako yankho limalamulidwa ndi ma micelles, omwe amagwira ntchito ngati ma microreactors popanga nanopowders. Ndi kuwonjezeka kwa mphamvu, dongosololi limasinthasintha pang'onopang'ono kukhala mkhalidwe wamadzimadzi wa crystalline.
Pamene kuchuluka kwa madzi a surfactant kufika pa CMC, kupangika kwa micelles kumaonekera kwambiri pamene kuchuluka kwa madzi kumawonjezeka. Izi zimadziwika ndi mfundo yolowera mu mphamvu ya pamwamba poyerekeza ndi logi (γ–log c curve), pamodzi ndi kutuluka kwa zinthu zakuthupi ndi za mankhwala zomwe sizili bwino mu yankho.
Ma micelles a Ionic surfactant amakhala ndi mphamvu zapamwamba pamwamba. Chifukwa cha kukoka kwa electrostatic, ma counterion amakokedwa ndi pamwamba pa micelle, zomwe zimapangitsa kuti gawo la ma positive ndi negative charges lisamayende bwino. Komabe, ma micelles akapanga mapangidwe amphamvu kwambiri, mphamvu yochepetsera mpweya wa ionic womwe umapangidwa ndi ma counterions imawonjezeka kwambiri—chinthu chomwe chingagwiritsidwe ntchito kusintha kufalikira kwa nanopowders. Pazifukwa ziwirizi, mphamvu yofanana ya yankho imachepa mofulumira ndi kuchuluka kwa centigrade kupitirira CMC, zomwe zimapangitsa kuti mfundoyi ikhale njira yodalirika yodziwira kuchuluka kwa micelle kofunikira kwa ma surfactants.
Kapangidwe ka ma micelles a ionic surfactant nthawi zambiri amakhala ozungulira, okhala ndi magawo atatu: pakati, chipolopolo, ndi gawo lamagetsi losakanikirana. Pakati pake pamapangidwa ndi unyolo wa hydrocarbon womwe umathira madzi, wofanana ndi ma hydrocarbon amadzimadzi, wokhala ndi mainchesi kuyambira pafupifupi 1 mpaka 2.8 nm. Magulu a methylene (-CH₂-) omwe ali pafupi ndi magulu a polar head ali ndi polarity pang'ono, kusunga mamolekyu ena amadzi kuzungulira pakati. Chifukwa chake, pakati pa micelle mulimadzi ambiri ogwidwa, ndipo magulu a -CH₂- awa saphatikizidwa mokwanira mu hydrocarbon core yonga madzi koma m'malo mwake amapanga gawo la chipolopolo cha micelle chosakhala chamadzimadzi.
Chipolopolo cha micelle chimadziwikanso kuti micelle-water interface kapena surface phase. Sichikutanthauza ma macroscopic interface pakati pa micelles ndi madzi koma m'malo mwake dera pakati pa micelles ndi monomeric aqueous surfactant solution. Pa ma ionic surfactant micelles, chipolopolocho chimapangidwa ndi Stern layer yamkati (kapena fixed adsorption layer) ya electric double layer, yokhala ndi makulidwe a pafupifupi 0.2 mpaka 0.3 nm. Chipolopolocho sichili ndi magulu a ionic head a surfactants ndi gawo la ma bound counterions komanso hydration layer chifukwa cha hydration ya ma ions awa. Chipolopolo cha micelle si malo osalala koma ndi "rough" interface, chifukwa cha kusinthasintha komwe kumachitika chifukwa cha kutentha kwa mamolekyulu a surfactant monomer.
Mu malo osakhala amadzi (ochokera ku mafuta), komwe mamolekyu amafuta amakhala ambiri, magulu a ma surfactants okonda madzi amasonkhana mkati kuti apange maziko a polar, pomwe maunyolo a hydrocarbon okonda madzi amapanga chipolopolo chakunja cha micelle. Mtundu uwu wa micelle uli ndi kapangidwe kosinthika poyerekeza ndi ma micelles amadzi wamba ndipo motero amatchedwa reverse micelle; Mosiyana ndi zimenezi, ma micelles opangidwa m'madzi amatchedwa normal micelles. Chithunzi 4 chikuwonetsa chitsanzo cha ma micelles okonda madzi opangidwa ndi ma surfactants m'njira zopanda madzi. M'zaka zaposachedwa, ma micelles okonda madzi akhala akugwiritsidwa ntchito kwambiri popanga ndi kukonza zonyamula mankhwala a nanoscale, makamaka poyikamo mankhwala okonda madzi.
Nthawi yotumizira: Disembala-26-2025