Papamuri Rangahau
Hei rauemi taiao, nui, me te whakahou, he nui ngā wero o te cellulose i roto i ngā mahi mahi nā te mea kāore e rewa me te iti o ngā āhuatanga wairewa. Ko te nui o te tioata me ngā here hauwai matotoru i roto i te hanganga cellulose ka pirau engari kāore e rewa i te wā e pupurihia ana, ā, kāore e rewa i roto i te wai me te nuinga o ngā whakarewa waro. Ka puta mai ō rātou hua mai i te esterification me te etherification o ngā rōpū hydroxyl i runga i ngā waeine anhydroglucose i roto i te mekameka polymer, ā, ka whakaatu i ētahi āhuatanga rerekē ki te cellulose taiao. Ka taea e te tauhohenga etherification o te cellulose te whakaputa i te maha o ngā ethers cellulose wairewa-wai, pērā i te methyl cellulose (MC), te hydroxyethyl cellulose (HEC) me te hydroxypropyl cellulose (HPC), e whakamahia whānuitia ana i roto i te kai, te whakapaipai, i roto i ngā rongoā me te rongoā. Ka taea e te CE wairewa-wai te hanga i ngā polymer here-hauwai me ngā waikawa polycarboxylic me ngā polyphenols.
He tikanga whai hua te huihuinga paparanga-i-te-paparanga (LBL) mō te whakarite i ngā kiriata angiangi hiato polymer. E whai ake nei ka whakamāramahia te huihuinga LBL o ngā CE rerekē e toru o HEC, MC me HPC me te PAA, ka whakataurite i te whanonga huihuinga, ka tātarihia te awe o ngā whakakapinga ki te huihuinga LBL. Tirohia te pānga o te pH ki te matotoru o te kiriata, me ngā rerekētanga rerekē o te pH ki te hanganga me te whakarewanga o te kiriata, me te whakawhanake i ngā āhuatanga mimiti wai o te CE/PAA.
Ngā Rauemi Whakamātautau:
Waikawa Polyacrylic (PAA, Mw = 450,000). Ko te matotoru o te otinga wai 2wt.% o te hydroxyethylcellulose (HEC) he 300 mPa·s, ā, ko te nekehanga o te whakakapinga he 2.5. Methylcellulose (MC, he otinga wai 2wt.% me te matotoru o te 400 mPa·s me te nekehanga o te whakakapinga o te 1.8). Hydroxypropyl cellulose (HPC, he otinga wai 2wt.% me te matotoru o te 400 mPa·s me te nekehanga o te whakakapinga o te 2.5).
Te whakarite kiriata:
I whakaritea mā te huihuinga paparanga tioata wai i runga i te silicon i te 25°C. Ko te tikanga maimoatanga o te matihiko kiriata e whai ake nei: rumakina ki roto i te otinga waikawa (H2SO4/H2O2, 7/3Vol/VOL) mō te 30 meneti, kātahi ka horoia ki te wai whakakore iona kia maha ngā wā tae noa ki te noho kūpapa o te pH, ā, ka maroke ki te hauota parakore. Ka mahia te huihuinga LBL mā te whakamahi i ngā mīhini aunoa. I rumakina te papa ki roto i te otinga CE (0.2 mg/mL) me te otinga PAA (0.2 mg/mL), ka rumakina ia otinga mō te 4 meneti. E toru ngā rumakina horoi, 1 meneti ia ia ki roto i te wai whakakore iona i mahia i waenganui i ia rumakina otinga hei tango i te polymer e piri koretake ana. I whakatikatikaina ngā uara pH o te otinga huihuinga me te otinga horoi ki te pH 2.0. Ko ngā kiriata i whakaritea kua tohua ko (CE/PAA)n, ko n te tohu o te huringa huihuinga. Ko (HEC/PAA)40, (MC/PAA)30 me (HPC/PAA)30 te nuinga o ngā mea i whakaritea.
Te Whakaahuatanga o te Kiriata:
I tuhia ngā hihi whakaata tata-noa, ā, i tātarihia ki te NanoCalc-XR Ocean Optics, ā, i inehia te matotoru o ngā kiriata i whakatakotoria ki runga i te silicon. Me te papa silicon kau hei papamuri, i kohia te hihi FT-IR o te kiriata angiangi i runga i te papa silicon ki runga i te ine hihi infrared Nicolet 8700.
Ngā taunekeneke here hauwai i waenga i ngā PAA me ngā CE:
Te huihuinga o HEC, MC me HPC me PAA ki roto i ngā kiriata LBL. Kei te whakaatuhia ngā hihi infrared o HEC/PAA, MC/PAA me HPC/PAA i roto i te pikitia. Ka kitea mārama ngā tohu IR kaha o PAA me CES i roto i ngā hihi IR o HEC/PAA, MC/PAA me HPC/PAA. Ka taea e te hihi FT-IR te tātari i te hononga hauwai i waenga i a PAA me CES mā te aroturuki i te nekehanga o ngā roopu mimiti āhuatanga. Ko te hononga hauwai i waenga i a CES me PAA ka puta i waenga i te hāora hydroxyl o CES me te rōpū COOH o PAA. I muri i te hanganga o te hononga hauwai, ka neke te whero tihi totoro ki te ahunga auau iti.
I kitea he tihi o te 1710 cm-1 mō te paura PAA parakore. I te wā i huihuia ai te polyacrylamide ki roto i ngā kiriata me ngā CE rerekē, ko ngā tihi o ngā kiriata HEC/PAA, MC/PAA me MPC/PAA i kitea i te 1718 cm-1, 1720 cm-1 me te 1724 cm-1. Ki te whakatauritea ki te paura PAA parakore, ko te roa o ngā tihi o ngā kiriata HPC/PAA, MC/PAA me HEC/PAA i nekehia e te 14, 10 me te 8 cm−1. Ko te here hauwai i waenga i te hāora ether me te COOH ka motuhia te here hauwai i waenga i ngā rōpū COOH. Ko te nui ake o ngā here hauwai i hangaia i waenga i te PAA me te CE, ko te nui ake o te nekehanga tihi o te CE/PAA i roto i ngā hihi IR. Ko te HPC te taumata teitei rawa o te matatini here hauwai, ko te PAA me te MC kei waenganui, ā, ko te HEC te mea iti rawa.
Te whanonga tipu o ngā kiriata hiato o ngā PAA me ngā CE:
I tirotirohia te whanonga hanga kiriata o ngā PAA me ngā CE i te wā o te huihuinga LBL mā te whakamahi i te QCM me te ine ine ira. He whai hua te QCM mō te aroturuki i te tipu o te kiriata i roto i te wāhi i ngā huringa huihuinga tuatahi. He pai ngā ine ira mō ngā kiriata kua whakatipuria neke atu i te 10 huringa.
I whakaatuhia e te kiriata HEC/PAA he tipu rārangi puta noa i te tukanga huihuinga LBL, ko ngā kiriata MC/PAA me HPC/PAA i whakaatu i te tipu taupū i ngā wāhanga tōmua o te huihuinga, kātahi ka huri hei tipu rārangi. I te rohe tipu rārangi, ko te teitei ake o te taumata o te matatini, ko te nui ake o te tipu matotoru mō ia huringa huihuinga.
Te pānga o te pH o te otinga ki te tipu o te kiriata:
Ka pā te uara pH o te otinga ki te tipu o te kiriata hiato pūmua here hauwai. Hei polyelectrolyte ngoikore, ka ionized te PAA ka utaina kinotia i te pikinga o te pH o te otinga, ā, ka aukati i te hononga here hauwai. Ina tae te taumata ionization o te PAA ki tētahi taumata, kāore e taea e te PAA te whakakotahi hei kiriata me ngā kaiwhiwhi here hauwai i roto i te LBL.
I heke te matotoru o te kiriata i te pikinga ake o te pH o te otinga, ā, i heke ohorere te matotoru o te kiriata i te pH 2.5 HPC/PAA me te pH 3.0-3.5 HPC/PAA. Ko te pūwāhi aro nui o te HPC/PAA he tata ki te pH 3.5, ko te pūwāhi aro nui o te HEC/PAA he tata ki te 3.0. Ko te tikanga tēnei, ina teitei ake te pH o te otinga huihuinga i te 3.5, kāore e taea te hanga i te kiriata HPC/PAA, ā, ina teitei ake te pH o te otinga i te 3.0, kāore e taea te hanga i te kiriata HEC/PAA. Nā te nui ake o te hononga hauwai o te kiriuhi HPC/PAA, he teitei ake te uara pH aro nui o te kiriuhi HPC/PAA i te kiriuhi HEC/PAA. I roto i te otinga kore-tote, ko ngā uara pH aro nui o ngā matatini i hangaia e HEC/PAA, MC/PAA me te HPC/PAA he tata ki te 2.9, 3.2 me te 3.7. He teitei ake te pH whakahirahira o te HPC/PAA i tō te HEC/PAA, he rite tonu ki te pH o te kiriuhi LBL.
Te mahi mimiti wai o te kiriuhi CE/PAA:
He nui ngā rōpū hydroxyl o te CES, nō reira he pai te mimiti wai me te pupuri wai. Hei tauira, i tirohia te kaha mimiti o te membrane CE/PAA kua herea ki te hauwai ki te wai i roto i te taiao. Mā te interferometry spectral, ka piki ake te matotoru o te kiriata i te mimiti wai e te kiriata. I whakanohoia ki roto i te taiao me te haumākū ka taea te whakarite i te 25°C mō ngā hāora 24 kia tutuki ai te taurite mimiti wai. I whakamaroketia ngā kiriata i roto i te oumu korehau (40°C) mō ngā hāora 24 kia tangohia katoatia ai te makuku.
I te pikinga ake o te haumākū, ka matotoru te kiriata. I te wāhi iti o te haumākū o te 30%-50%, he puhoi te tipu o te matotoru. Ina neke atu te haumākū i te 50%, ka tere te tipu o te matotoru. Ki te whakatauritea ki te kiriuhi PVPON/PAA e herea ana ki te hauwai, ka taea e te kiriuhi HEC/PAA te mimiti i te wai mai i te taiao. I raro i te āhua o te haumākū whanaunga o te 70% (25°C), ko te whānuitanga matotoru o te kiriata PVPON/PAA he tata ki te 4%, ko te whānuitanga matotoru o te kiriata HEC/PAA he teitei ake i te 18%. I whakaatuhia e ngā hua ahakoa he nui ngā rōpū OH i roto i te pūnaha HEC/PAA i uru ki te hanganga o ngā here hauwai, he nui tonu ngā rōpū OH e taunekeneke ana ki te wai i roto i te taiao. Nō reira, he pai ngā āhuatanga mimiti wai o te pūnaha HEC/PAA.
hei whakamutunga
(1) Ko te pūnaha HPC/PAA me te tohu here hauwai teitei rawa o CE me PAA te mea tere rawa te tipu i roto i a rātou, ko te MC/PAA kei waenganui, ā, ko te HEC/PAA te mea iti rawa.
(2) I whakaatuhia e te kiriata HEC/PAA tētahi momo tipu rārangi puta noa i te tukanga whakarite, ko ngā kiriata e rua kē atu, MC/PAA me HPC/PAA, i whakaatu i tētahi tipu taupū i ngā huringa tuatahi, kātahi ka hurihia hei momo tipu rārangi.
(3) He kaha te whakawhirinaki o te tipu o te kiriata CE/PAA ki te pH o te otinga. Ina teitei ake te pH o te otinga i tōna pūwāhi matua, kāore e taea e te PAA me te CE te whakakotahi hei kiriata. Ka taea te wairewa i te kiriuhi CE/PAA kua whakakotahihia ki ngā otinga pH teitei.
(4) Nā te mea he nui te OH me te COOH o te kiriata CE/PAA, ka honoa ngātahitia e te maimoatanga wera. He pai te pumau o te kiriuhi CE/PAA honoa ngātahi, ā, kāore e wairewa i roto i ngā wairewa pH teitei.
(5) He pai te kaha o te kiriata CE/PAA ki te mimiti i te wai i roto i te taiao.
Wā tuku: 18-Pepuere-2023