Pānga mākū, whakaritenga: HLB: 7-9
Ko te makuku te tikanga o te āhuatanga e mimitihia ana te hau e piri ana ki te mata totoka e te wai. Ko ngā matū ka taea te whakarei ake i tēnei kaha nekehanga ka kiia he māngai makuku. E toru ngā momo o te makuku: te makuku whakapā (makuku piri), te makuku rumaki (makuku rumaki), me te makuku horapa (horapa). I roto i ēnei, ko te horapa te paerewa teitei rawa atu o te makuku, ā, he maha ngā wā ka whakamahia te tauwehenga horapa hei tohu hei aromatawai i te mahi makuku i waenga i ngā pūnaha rerekē. Hei tāpiri, ko te koki whakapā he paearu anō hoki hei aromatawai i te kounga o te makuku. Ka taea te whakamahi i ngā matū horoi hei whakahaere i te nui o te makuku i waenga i ngā āhua wai me te totoka.
I roto i te umanga patu pepeke, kei roto i ētahi o ngā whakatakotoranga kirikiri me ngā paura puehu he nui ngā matū horoi. Ko tā rātou kaupapa he whakapai ake i te piri me te nui o te whakatakotoranga o te patu pepeke ki te mata ūnga, he tere ake te tere tuku me te whakawhānui i te horapa o ngā matū hohe i raro i ngā āhuatanga makuku, ā, ka whakarei ake i te whai huatanga o te aukati me te rongoā i ngā mate.
I roto i te umanga whakapaipai, ka mahi ngā surfactants hei emulsifier, ā, he wāhanga nui i roto i ngā hua tiaki kiri pērā i ngā kirīmi, ngā hinu horoi, ngā horoi kanohi me ngā tango meika.
Ngā Micelles me te Whakarewatanga,ngā whakaritenga: C > CMC (HLB 13–18)
Ko te kukū iti rawa e hono ai ngā ngota surfactant ki te hanga micelles. Ina nui ake te kukū i te uara CMC, ka whakarite ngā ngota surfactant i a rātou anō ki ngā hanganga pēnei i te porowhita, te rite ki te tokotoko, te lamellar, te rite rānei ki te pereti.
He pūnaha taurite pāmahana ngā pūnaha whakarewa. Ko te iti o te CMC me te teitei o te hononga, ko te nui ake o te kukū tāpiri mōrahi (MAC). E toru ngā āhuatanga e whakaatahia ana te pānga o te pāmahana ki te whakarewa: ka pā ki te hanganga micelle, te wairewa o ngā wairewa, me te wairewa o ngā surfactants. Mō ngā surfactants ionic, ka piki tere te wairewa me te pikinga o te pāmahana, ā, ko te pāmahana e puta ai tēnei pikinga ohorere ka kiia ko te pūwāhi Krafft. Ko te teitei ake o te pūwāhi Krafft, ko te iti iho o te kukū micelle matua.
Mō ngā matū horoi kore-ionic polyoxyethylene, ina piki te pāmahana ki tētahi taumata, ka heke tere te wairewa, ā, ka puta te ua, ka huri te wai hei pōuri. E mōhiotia ana tēnei āhuatanga ko te kapua, ā, ko te pāmahana e rite ana ka kiia ko te pūwāhi kapua. Mō ngā matū horoi he rite te roa o te mekameka polyoxyethylene, ka roa ake te mekameka hauwaiwai, ka iti ake te pūwāhi kapua; i te ritenga atu, ki te rite te roa o te mekameka hauwaiwai, ka roa ake te mekameka polyoxyethylene, ka teitei ake te pūwāhi kapua.
He tino iti te wairewatanga o ngā matū waro kore-poari (hei tauira, te benzene) ki te wai. Heoi, mā te tāpiri i ngā matū whakaora pērā i te konutai oleate ka taea te whakanui ake i te wairewatanga o te benzene ki te wai—he tukanga e kiia nei ko te wairewatanga. He rerekē te wairewatanga i te wairewatanga noa: kāore te benzene wairewatanga e horapa ōrite ana i roto i ngā ngota wai engari e mau ana i roto i ngā micelles i hangaia e ngā katote oleate. Kua whakaūhia e ngā rangahau diffraction hihi-X ka whānui ngā momo micelles katoa ki ngā taumata rerekē i muri i te wairewatanga, ko ngā āhuatanga colligative o te otinga whānui kāore i te tino rerekē.
I te pikinga ake o te kukū o ngā matū horoi i roto i te wai, ka kohikohi ngā ngota matū horoi ki runga i te mata wai hei hanga i tētahi paparanga monomolecular piripono, he mea whakatakoto. Ka huihui ngā ngota taikaha i roto i te wāhanga papatipu me ō rātou rōpū hydrophobic e anga ana ki roto, ka hanga i ngā micelles. Ko te kukū iti rawa e hiahiatia ana hei tīmata i te hanganga micelle ka tautuhia ko te kukū micelle tino nui (CMC). I tēnei kukū, ka rerekē te otinga i te whanonga pai, ā, ka puta he pūwāhi hurihuri motuhake i runga i te pihi kukū mata me te kukū. Mā te whakanui ake i te kukū matū horoi e kore e whakaiti i te kukū mata; engari, ka whakatairanga i te tipu tonu me te whakarea o ngā micelles i roto i te wāhanga papatipu.
Ina marara ngā ngota surfactant i roto i te otinga, ā, ka tae ki tētahi paepae kukū motuhake, ka honoa mai i ngā monomer takitahi (ngā katote, ngā ngota rānei) ki roto i ngā kohikohinga colloidal e kiia nei ko ngā micelles. Ka puta he panoni ohorere i roto i ngā āhuatanga ā-tinana me te matū o te otinga i tēnei whakawhiti, ā, ko te kukū e puta ai tēnei ko te CMC. Ko te tukanga hanganga micelle e kiia ana ko te micellization.
He tukanga e whakawhirinaki ana ki te kukū te hanganga o ngā micelle i roto i ngā otinga surfactant wai. I roto i ngā otinga tino waimeha, tata tonu te pa atu o te wai me te hau, nō reira he iti noa te hekenga o te taumahatanga o te mata, e tata tonu ana ki te wai parakore, he iti noa iho ngā ngota surfactant e marara ana i te wāhanga papatipu. I te piki haere o te kukū o te surfactant, ka tere te mimiti o ngā ngota ki te mata o te wai, ka whakaiti i te horapa o te pa i waenga i te wai me te hau, ā, ka heke tere te taumahatanga o te mata. I taua wā, ka huihui ētahi ngota surfactant i roto i te wāhanga papatipu me ō rātou rōpū hydrophobic e hono ana, ka hanga he micelle iti.
I te piki haere tonu o te kukū, ā, ka tae te otinga ki te mimiti o te matū, ka puta he kiriata monomolecular kikī ki te mata wai. Ina pā te kukū ki te CMC, ka tae te taumahatanga o te mata o te otinga ki tōna uara iti rawa. I tua atu i te CMC, ko te whakanui ake i te kukū o te surfactant kāore e pā ki te taumahatanga o te mata; engari, ka whakanui ake i te maha me te rahi o ngā micelles i te wāhanga papatipu. Kātahi ka whakahaerehia te otinga e ngā micelles, e mahi ana hei microreactors i roto i te hanga o ngā nanopaura. I te piki haere tonu o te kukū, ka neke haere te pūnaha ki te āhua tioata wai.
Ina tae te kukū o te wai surfactant ki te CMC, ka kitea te hanganga o ngā micelles i te pikinga o te kukū. Ka kitea tēnei mā te pūwāhi piko i roto i te pihi kukū o te taumahatanga mata me te kukū o te log (pihi γ–log c), me te putanga mai o ngā āhuatanga ā-tinana me te matū kāore i te tino pai i roto i te wai.
He nui ngā utu mata o ngā micelle surfactant ionic. Nā te kukume hiko, ka kukumea ngā counterion ki te mata o ngā micelle, ka whakakore i ētahi wāhanga o ngā utu pai me ngā utu kino. Heoi, ina hangaia e ngā micelle he hanganga utu nui, ka nui haere te kaha whakaroa o te hau ionic i hangaia e ngā counterion—he āhuatanga ka taea te whakamahi hei whakatika i te marara o ngā nanopaura. Mō ēnei take e rua, ka tere te heke o te kawe hiko ōrite o te otinga me te pikinga o te kukū ki tua atu i te CMC, ka waiho tēnei wāhi hei tikanga pono mō te whakatau i te kukū micelle matua o ngā surfactants.
He porowhita te hanganga o ngā micelle surfactant ionic, e toru ngā wāhanga: he matua, he anga, me te paparanga hiko rua horapa. He mekameka hauwaiwai hydrophobic te matua, he rite ki ngā hauwaiwai wai, me te diameter mai i te 1 ki te 2.8 nm. He pōraruraru wāhanga ngā rōpū methylene (-CH₂-) e tata ana ki ngā rōpū pane polar, e pupuri ana i ētahi ngota wai huri noa i te matua. Nō reira, kei roto i te matua micellehe nui te wai kua mau, ā, kāore ēnei rōpū -CH₂- i tino whakaurua ki roto i te matua hauwaiwai rite-wai engari he wāhanga kē o te anga micelle kore-wai.
E mōhiotia ana hoki te anga micelle ko te atanga micelle-wai, ko te mata rānei. Kāore e pā ana ki te atanga whānui i waenga i ngā micelle me te wai, engari ko te rohe i waenga i ngā micelle me te otinga surfactant wai monomeric. Mō ngā micelle surfactant ionic, ka hangaia te anga e te paparanga Stern o roto rawa (te paparanga adsorption fixed rānei) o te paparanga takirua hiko, me te matotoru o te 0.2 ki te 0.3 nm. Kei roto i te anga ehara i te mea ko ngā rōpū upoko ionic o ngā surfactants me tētahi wāhanga o ngā counterions herea engari he paparanga whakamakuku hoki nā te whakamakuku o ēnei ions. Ehara te anga micelle i te mata maeneene engari he atanga "taratara", he hua o ngā huringa i puta mai i te nekehanga wera o ngā ngota monomer surfactant.
I roto i ngā pāpāho kore-wai (e ahu mai ana i te hinu), ko te wāhi e nui ake ai ngā ngota hinu, ka huihui ngā rōpū hydrophilic o ngā surfactants ki roto hei hanga i te matua porotaka, ko ngā mekameka hauwaiwai hydrophobic e hanga ana i te anga o waho o ngā micelle. He hanganga whakahurihuri tō tēnei momo micelle ki te whakataurite ki ngā micelle wai tuku iho, nō reira ka kiia he micelle whakamuri; he rerekē, ko ngā micelle i hangaia i roto i te wai ka kiia he micelle noa. E whakaatu ana te Pikitia 4 i tētahi tauira kauwhata o ngā micelle whakahurihuri i hangaia e ngā surfactants i roto i ngā otinga kore-wai. I ngā tau tata nei, kua whānuitia te whakamahinga o ngā micelle whakahurihuri i roto i te hanga me te whakarite i ngā kaikawe rongoā nanoscale, inā koa mō te whakakī i ngā rongoā hydrophilic.
Wā tuku: Hakihea-26-2025