Noiʻi Holomua ma Non-Isocyanate Polyurethanes
Mai ko lākou hoʻomaka ʻana i ka makahiki 1937, ua loaʻa nā mea polyurethane (PU) i nā noi nui ma nā ʻāpana like ʻole e like me ka halihali, kūkulu hale, petrochemicals, textiles, mechanical and electrical engineering, aerospace, healthcare, a me ka mahiʻai. Hoʻohana ʻia kēia mau mea i nā ʻano e like me nā plastic foam, fibers, elastomers, waterproofing agents, synthetic leather, coatings, adhesives, paving material a me nā lako olakino. Hoʻokumu mua ʻia ka PU kuʻuna mai ʻelua a ʻoi aku isocyanates me nā polyols macromolecular a me nā mea hoʻonui kaulahao liʻiliʻi. Eia nō naʻe, ʻo ka ʻawaʻawa o ka isocyanates he mea nui ia i ke olakino kanaka a me ke kaiapuni; ʻOi aku ka mea maʻamau i loaʻa mai ka phosgene-he mea ʻawaʻawa nui loa-a me nā mea waiwai amine e pili ana.
Ma muli o ka ʻimi ʻana o ka ʻoihana kemika o kēia wā i nā hana hoʻomohala ʻōmaʻomaʻo a paʻa mau, ua hoʻonui nui ʻia ka poʻe noiʻi i ka hoʻololi ʻana i nā isocyanates me nā kumuwaiwai kūlohelohe ʻoiai e ʻimi ana i nā ala synthesis novel no nā polyurethanes non-isocyanate (NIPU). Hōʻike kēia pepa i nā ala hoʻomākaukau no ka NIPU me ka nānā ʻana i nā holomua ma nā ʻano NIPU like ʻole a kūkākūkā i kā lākou mau mea e hiki mai ana e hāʻawi i kahi kuhikuhi no ka noiʻi hou aku.
1 Hoʻohui i nā Polyurethanes Non-Isocyanate
ʻO ka hana mua ʻana o nā pūhui carbamate haʻahaʻa haʻahaʻa me ka hoʻohana ʻana i nā carbonates monocyclic i hui pū ʻia me nā diamine aliphatic i hana ʻia ma nā ʻāina ʻē i ka makahiki 1950-e hōʻailona ana i kahi manawa koʻikoʻi i ka synthesis polyurethane non-isocyanate. I kēia manawa aia ʻelua mau ʻano kumu mua no ka hana ʻana i ka NIPU: ʻO ka mea mua e pili ana i nā hopena hoʻohui stepwise ma waena o nā carbonates cyclic binary a me nā amine binary; ʻO ka lua e pili ana i nā hopena polycondensation e pili ana i nā intermediates diurethane me nā diols e hoʻomaʻamaʻa i ka hoʻololi ʻana i loko o nā carbamates. Hiki ke loaʻa nā mea waena Diamarboxylate ma o nā ala cyclic carbonate a i ʻole dimethyl carbonate (DMC); ʻO ke kumu, ke hana nei nā ʻano hana a pau ma o nā hui ʻakika carbonic e hāʻawi ana i nā hana carbamate.
Hōʻike ʻia nā ʻāpana aʻe i ʻekolu ala ʻokoʻa i ka synthesizing polyurethane me ka hoʻohana ʻole ʻana i ka isocyanate.
1.1Binary Cyclic Carbonate Alanui
Hiki ke hoʻohui ʻia ka NIPU ma o nā hoʻohui stepwise e pili ana i ka carbonate cyclic binary i hui pū ʻia me ka amine binary e like me ka mea i hōʻike ʻia ma ke Kiʻi 1.
Ma muli o ka nui o nā pūʻulu hydroxyl e loaʻa ana i loko o nā ʻāpana hana hou ma kāna ʻano kaulahao nui e loaʻa i kēia ʻano ka mea i kapa ʻia he polyβ-hydroxyl polyurethane (PHU). Ua hoʻomohala ʻo Leitsch et al., i nā PHU polyether e hoʻohana ana i nā polyethers cyclic carbonate-terminated ma ka ʻaoʻao o nā amine binary me nā molekole liʻiliʻi i loaʻa mai nā carbonates cyclic binary—e hoʻohālikelike ana i kēia me nā hana kuʻuna i hoʻohana ʻia no ka hoʻomākaukau ʻana i nā polyether PU. Ua hōʻike ʻia kā lākou ʻike ʻana e hana maʻalahi nā hui hydroxyl i loko o nā PHU i nā paʻa hydrogen me nā ʻātoma nitrogen/oxygen i loko o nā ʻāpana palupalu/paʻakikī; ʻO nā ʻano like ʻole ma waena o nā ʻāpana palupalu e hoʻopili i ka ʻano hoʻopaʻa hydrogen a me nā degere hoʻokaʻawale microphase e pili ana i nā ʻano hana holoʻokoʻa.
ʻO ka mea maʻamau ma lalo o ka mahana ma mua o 100 °C ʻaʻole kēia ala e hoʻopuka i nā huahana i ka wā o nā kaʻina hana e hoʻohālikelike ai i ka maʻu ʻoiai e hāʻawi ana i nā huahana kūpaʻa ʻole me ka hopohopo volatility akā pono nā mea hoʻoheheʻe organik i hōʻike ʻia e ka polarity ikaika e like me dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF) a hiki i ʻelima mau lā i hoʻonui pinepine ʻia ma waena o ka lā hoʻokahi. e hāʻule pinepine ana nā kaumaha molekala haʻahaʻa ma lalo o nā paepae ma kahi o 30k g/mol e lilo ana i mea paʻakikī i ka hana nui ma muli o ke kumu nui o nā kumukūʻai kiʻekiʻe e pili ana i laila a me ka lawa ʻole o ka ikaika i hōʻike ʻia e nā PHU hopena ʻoiai ʻo nā noi hoʻohiki e pili ana i nā mea hoʻoheheʻe ʻana i nā mea hoʻomanaʻo hoʻomanaʻo.
1.2Monocylic Carbonate Alanui
Hoʻopili pololei ʻo Monocylic carbonate me ka diamine i loaʻa i ka dicarbamate i loaʻa nā pūʻulu hopena hydroxyl a laila e hana i nā pilina transesterification/polycondensation kūikawā ma ka ʻaoʻao o nā diols e hoʻohua ai i kahi NIPU i hoʻohālikelike ʻia i nā mea kuʻuna i hōʻike ʻia ma ke Kiʻi 2.
ʻO nā ʻano like ʻole monocylic i hoʻohana mau ʻia me ka ethylene & propylene carbonated substrates kahi i hana ai ka hui o Zhao Jingbo ma Beijing University of Chemical Technology i nā diamine like ʻole e pane ana iā lākou e kūʻē i nā hui cyclical i loaʻa mua i nā intermediary dicarbamate ma mua o ka hoʻomaka ʻana i nā ʻāpana condensation me ka hoʻohana ʻana i nā laina polytetrapolyefuranediol / hōʻikeʻike maikaʻi loa. nā waiwai wela/mechanical e piʻi ana i luna nā wahi heheʻe e lele ana a puni ka laulā e hoʻonui ana ma kahi o125~161 °C ikaika tensile piʻi kokoke i ka 24MPa elongation rates nearing1476%. ʻO Wang et al., nā hui leverage like me DMC i hui pū ʻia me ka hexamethylenediamine/cyclocarbonated precursors synthesizing hydroxy-terminated derivatives ma hope i hoʻokomo ʻia i nā waika biobased dibasic e like me ka oxalic/sebacic/acids adipic-acid-terephtalics e loaʻa ana i nā hopena hope loa e hōʻike ana i nā pae g8k fluctuating9~17 MPa elongations varying35%~235%.
Hoʻohana maikaʻi nā esters Cyclocarbonic me ka ʻole e koi i nā catalysts ma lalo o nā kūlana maʻamau e mālama ana i ka mahana wela ma kahi o 80° a i 120°C ma hope o nā transesterifications e hoʻohana mau i nā ʻōnaehana catalytic ma muli o organotin e hōʻoiaʻiʻo ana i ka hana maikaʻi ʻaʻole ʻoi aku ma mua o 200°. Ma waho aʻe o nā hoʻoikaika condensation e huli ana i nā mea hoʻokomo diolic hiki ke hoʻololi i nā hanana ponoʻi polymerization/deglycolysis e hoʻoikaika i nā hopena i makemake ʻia e hoʻolilo i nā ʻano hana i ka hoʻopōmaikaʻi ʻana i ka kaiaola e hāʻawi ana i nā koena methanol/liʻiliʻi-mole-diolic e hōʻike ana i nā ʻoihana ʻoihana e neʻe nei i mua.
1.3Dimethyl Carbonate Alanui
Hōʻike ʻo DMC i kahi ʻano ʻona maikaʻi ʻole a ʻona ʻole e hōʻike ana i nā ʻāpana hana he nui e komo pū me methyl/methoxy/carbonyl configurations e hoʻonui ana i nā profile reactivity e hiki ai i nā hana mua kahi e launa pū ai ʻo DMC me nā diamine e hana ana i nā mea waena liʻiliʻi i hoʻopau ʻia ka methyl-carbamate ma hope o nā hana hoʻoheheʻe hoʻoheheʻe. liʻiliʻi-hoʻonui-diolics/nui-polyol mea e alakaʻi ana i ka puka hope ʻimi ʻia nā hale polymer i ʻike ʻia e like me ka Figure3.
Deepa et.al i hoʻonui ʻia ma luna o ka dynamics i ʻōlelo ʻia aʻe nei e hoʻohana ana i ka sodium methoxide catalysis e hoʻolalelale ana i nā ʻano hana waena like ʻole ma hope o ka hoʻopili ʻana i nā hoʻonui i hoʻopaʻa ʻia e hoʻopau ana i ka moʻo like ʻana i nā haku ʻāpana paʻakikī e loaʻa ana nā kaupaona molekala e pili ana (3 ~20)x10^3g/molanning glass transition temperatures-3°C). Ua koho ʻo Pan Dongdong i nā pairing hoʻolālā e loaʻa ana he DMC hexamethylene-diaminopolycarbonate-polalcohols e ʻike ana i nā hopena koʻikoʻi e hōʻike ana i nā metric tensile-ikaika oscillating10-15MPa elongation ratios kokoke 1000% -1400%. ʻO nā ʻimi noiʻi e hoʻopuni ana i nā mana hoʻonui kaulahao like ʻole i hōʻike ʻia i nā makemake e hoʻohālikelike maikaʻi i nā koho butanediol/hexanediol i ka wā i mālama ʻia ai ke kaulike o ka helu atomika e hāpai ana i ka hoʻonui ʻana i ka crystallinity i ʻike ʻia ma nā kaulahao. ʻO nā ʻimi hou aku i manaʻo ʻia e loaʻa ana i ka non-isocyante-polyureas e hoʻohana ana i ka hoʻopili diazomonomer i manaʻo ʻia nā noi pena e kū mai ana nā pono hoʻohālikelike ma mua o nā hoa vinyl-carbonaceous e hōʻike ana i ka maikaʻi o ke kumu kūʻai. no laila e ho'ēmi ana i nā kahawai ʻōpala i kaupalena ʻia wale nō methanol/liʻiliʻi-mole-diolic effluents e hoʻokumu ana i nā paradigms syntheses ʻōmaʻomaʻo holoʻokoʻa.
2 Nā ʻāpana palupalu like ʻole o ka polyurethane non-isocyanate
2.1 Polyether polyurethane
Hoʻohana nui ʻia ka polyether polyurethane (PEU) ma muli o kona ikehu haʻahaʻa haʻahaʻa o nā paʻa ether i nā ʻāpana haʻahaʻa haʻahaʻa, hoʻololi maʻalahi, haʻahaʻa haʻahaʻa haʻahaʻa haʻahaʻa a me ke kūpaʻa hydrolysis.
Kebir et al. synthesized polyether polyurethane me DMC, polyethylene glycol a me butanediol e like me nā mea maka, akā he haʻahaʻa ke kaumaha mole (7 500 ~ 14 800g / mol), ua emi iho ka Tg ma mua o 0 ℃, a ua haʻahaʻa hoʻi ka helu heheʻe (38 ~ 48 ℃), a ua paʻakikī ka ikaika a me nā hōʻailona ʻē aʻe o ka hoʻohana. Ua hoʻohana ka hui noiʻi o Zhao Jingbo i ka ethylene carbonate, 1, 6-hexanediamine a me ka polyethylene glycol e synthesize PEU, nona ka molecular kaumaha o 31 000g / mol, tensile ikaika o 5 ~ 24MPa, a me ka elongation ma ka haki o 0.9% ~ 1 388%. ʻO ke kaumaha o ka molecular o ka synthesized series of aromatic polyurethanes he 17 300 ~ 21 000g / mol, ka Tg he -19 ~ 10 ℃, ka helu hoʻoheheʻe he 102 ~ 110 ℃, ka ikaika tensile he 12 ~ 38MPa, a me ka elastic recovery rate o 200% 9%.
Ua hoʻomākaukau ka pūʻulu noiʻi o Zheng Liuchun a me Li Chuncheng i ka waena 1, 6-hexamethylenediamine (BHC) me ka dimethyl carbonate a me 1, 6-hexamethylenediamine, a me ka polycondensation me nā moleke liʻiliʻi liʻiliʻi pololei kaulahao diols a me polytetrahydrofuranediols (Mn=2 000). Ua hoʻomākaukau ʻia kahi moʻo polyether polyurethanes (NIPEU) me ke ala ʻole isocyanate, a ua hoʻoholo ʻia ka pilikia crosslinking o nā mea waena i ka wā o ka hopena. Ua hoʻohālikelike ʻia ke ʻano a me nā waiwai o ka polyether polyurethane kahiko (HDIPU) i hoʻomākaukau ʻia e NIPEU a me 1, 6-hexamethylene diisocyanate, e like me ka hōʻike ʻana ma ka Papa 1.
| Laʻana | Māhele paʻakikī nuipa/% | Kaumaha molekula/(g·mol^(-1)) | Helu helu māhele paona molekala | Ka ikaika uʻi/MPa | Elongation ma ka hoomaha/% |
| NIPEU30 | 30 | 74000 | 1.9 | 12.5 | 1250 |
| NIPEU40 | 40 | 66000 | 2.2 | 8.0 | 550 |
| HDIPU30 | 30 | 46000 | 1.9 | 31.3 | 1440 |
| HDIPU40 | 40 | 54000 | 2.0 | 25.8 | 1360 |
Papa 1
Hōʻike nā hualoaʻa ma ka Papa 1 i ka ʻokoʻa o ke kūkulu ʻana ma waena o NIPEU a me HDIPU ma muli o ka māhele paʻakikī. ʻO ka hui urea i hana ʻia e ka ʻaoʻao ʻaoʻao o NIPEU ua hoʻokomo ʻia i loko o ke kaulahao molekika ʻāpana paʻakikī, e uhaʻi i ka ʻāpana paʻakikī e hana i nā paʻa hydrogen kauoha, ka hopena i nā kaulahao hydrogen nāwaliwali ma waena o nā kaulahao mole o ka ʻāpana paʻakikī a me ka crystallinity haʻahaʻa o ka māhele paʻakikī, e hopena i ka haʻahaʻa haʻahaʻa o ka NIPEU. ʻO ka hopena, ʻoi aku ka maikaʻi o kāna mau mea mechanical ma mua o HDIPU.
2.2 Polyester Polyurethane
ʻO ka polyester polyurethane (PETU) me nā polyester diols e like me nā ʻāpana palupalu he biodegradability maikaʻi, biocompatibility a me nā waiwai mechanical, a hiki ke hoʻohana ʻia no ka hoʻomākaukau ʻana i nā scaffolds ʻenekinia kiko, kahi mea biomedical me nā manaʻo noi nui. ʻO nā diol polyester i hoʻohana mau ʻia i nā ʻāpana palupalu he polybutylene adipate diol, polyglycol adipate diol a me polycaprolactone diol.
Ma mua, ʻo Rokicki et al. ua hoʻololi i ka ethylene carbonate me ka diamine a me nā diols ʻokoʻa (1, 6-hexanediol,1, 10-n-dodecanol) e loaʻa i nā NIPU ʻokoʻa, akā ʻo ka NIPU synthesized he haʻahaʻa molekala kaumaha a haʻahaʻa Tg. Farhadian et al. hoʻomākaukau ʻia ka polycyclic carbonate me ka hoʻohana ʻana i ka ʻaila hua sunflower ma ke ʻano he mea maka, a laila hui pū ʻia me nā polyamines bio-based, uhi ʻia ma kahi pā, a hoʻōla ʻia ma 90 ℃ no 24 mau hola e loaʻa ai ke kiʻiʻoniʻoni polyester polyurethane thermosetting, ka mea i hōʻike i ke kūpaʻa wela maikaʻi. ʻO ka hui noiʻi o Zhang Liqun mai South China University of Technology synthesized he moʻo o nā diamines a me cyclic carbonates, a laila condensed me biobased dibasic acid e loaʻa ai ka polyester polyurethane biobased. ʻO ka hui noiʻi a Zhu Jin ma Ningbo Institute of Materials Research, Chinese Academy of Science i hoʻomākaukau i ka diaminodiol ʻāpana paʻakikī me ka hoʻohana ʻana i ka hexadiamine a me ka vinyl carbonate, a laila polycondensation me ka bio-based unsaturated dibasic acid e loaʻa i kahi moʻo o ka polyester polyurethane, hiki ke hoʻohana ʻia e like me ka pena ma hope o ka hoʻōla ʻana o ka ultraviolet [23]. Ua hoʻohana ka hui noiʻi o Zheng Liuchun lāua ʻo Li Chuncheng i ka ʻakika adipic a me nā diol aliphatic ʻehā (butanediol, hexadiol, octanediol a me decanediol) me nā helu ʻātoma kalapona like ʻole e hoʻomākaukau i nā diols polyester e like me nā ʻāpana palupalu; Ua loaʻa i kahi hui o non-isocyanate polyester polyurethane (PETU), i kapa ʻia ma muli o ka helu o nā kalapona kalapona o aliphatic diols, ma ka hoʻoheheʻe ʻana i ka polycondensation me ka hydroxy-sealed ʻāpana paʻa prepolymer i hoʻomākaukau ʻia e BHC a me nā diols. Hōʻike ʻia nā waiwai mechanical o PETU ma ka Papa 2.
| Laʻana | Ka ikaika uʻi/MPa | Modulus elastic/MPa | Elongation ma ka hoomaha/% |
| PETU4 | 6.9±1.0 | 36±8 | 673±35 |
| PETU6 | 10.1±1.0 | 55±4 | 568±32 |
| PETU8 | 9.0±0.8 | 47±4 | 551±25 |
| PETU10 | 8.8±0.1 | 52±5 | 137±23 |
Papa 2
Hōʻike nā hopena i ka ʻāpana palupalu o PETU4 ke kiʻekiʻe o ka carbonyl density, ka paʻa hydrogen ikaika loa me ka ʻāpana paʻakikī, a me ka degere kaʻawale haʻahaʻa. Ua kaupalena ka crystallization o nā ʻāpana palupalu a paʻakikī, e hōʻike ana i ka helu heheʻe haʻahaʻa a me ka ikaika tensile, akā ʻo ka elongation kiʻekiʻe loa i ka wā haki.
2.3 Polycarbonate polyurethane
ʻO ka polycarbonate polyurethane (PCU), ʻoi aku ka aliphatic PCU, he kūpaʻa hydrolysis maikaʻi loa, kūpaʻa oxidation, kūpaʻa ola maikaʻi a me ka biocompatibility, a loaʻa iā ia nā manaʻo noi maikaʻi i ke kahua o ka biomedicine. I kēia manawa, hoʻohana ka hapa nui o ka NIPU i hoʻomākaukau ʻia i nā polyether polyols a me nā polyester polyols ma ke ʻano he mau ʻāpana palupalu, a he liʻiliʻi nā hōʻike noiʻi no ka polycarbonate polyurethane.
ʻO ka polyurethane polycarbonate non-isocyanate i hoʻomākaukau ʻia e ka hui noiʻi ʻo Tian Hengshui ma South China University of Technology he paona molekala ma mua o 50 000 g/mol. Ua aʻo ʻia ka mana o nā ʻano hopena i ke kaumaha molekala o ka polymer, akā ʻaʻole i hōʻike ʻia kona mau ʻano mechanical. Ua hoʻomākaukau ka hui noiʻi a Zheng Liuchun lāua ʻo Li Chuncheng i ka PCU me ka hoʻohana ʻana i ka DMC, hexanediamine, hexadiol a me polycarbonate diols, a ua kapa ʻia ʻo PCU e like me ka hapa nui o ka ʻāpana paʻakikī e hana hou ana. Hōʻike ʻia nā waiwai mechanical ma ka Papa 3.
| Laʻana | Ka ikaika uʻi/MPa | Modulus elastic/MPa | Elongation ma ka hoomaha/% |
| PCU18 | 17±1 | 36±8 | 665±24 |
| PCU33 | 19±1 | 107±9 | 656±33 |
| PCU46 | 21±1 | 150±16 | 407±23 |
| PCU57 | 22±2 | 210±17 | 262±27 |
| PCU67 | 27±2 | 400±13 | 63±5 |
| PCU82 | 29±1 | 518±34 | 26±5 |
Papa 3
Hōʻike nā hualoaʻa he kiʻekiʻe ka paona molekala PCU, a hiki i 6 × 104 ~ 9 × 104g / mol, helu hoʻoheheʻe a hiki i 137 ℃, a me ka ikaika tensile a hiki i 29 MPa. Hiki ke hoʻohana ʻia kēia ʻano PCU ma ke ʻano he plastik paʻa a i ʻole he elastomer, nona ka manaʻo hoʻohana maikaʻi i ke kahua biomedical (e like me nā scaffolds ʻenekini kiko kanaka a i ʻole nā mea hana implant cardiovascular).
2.4 Hybrid non-isocyanate polyurethane
ʻO ka Hybrid non-isocyanate polyurethane (hybrid NIPU) ka hoʻokomo ʻana o ka epoxy resin, acrylate, silica a i ʻole nā hui siloxane i loko o ka polyurethane molecular framework e hana i kahi pūnaewele interpenetrating, hoʻomaikaʻi i ka hana o ka polyurethane a hāʻawi i ka polyurethane i nā hana like ʻole.
Feng Yuelan et al. ua hoʻololi i ka ʻaila epoxy soybean bio-based me CO2 e synthesize pentamonic cyclic carbonate (CSBO), a hoʻokomo i ka bisphenol A diglycidyl ether (epoxy resin E51) me nā ʻāpana kaulahao ʻoi aku ka paʻakikī e hoʻomaikaʻi hou i ka NIPU i hana ʻia e CSBO paʻa me ka amine. Aia i loko o ke kaulahao molekala kekahi ʻāpana kaulahao lōʻihi o ka ʻakika oleic/linoleic acid. Loaʻa iā ia nā ʻāpana kaulahao ʻoi aku ka paʻakikī, i loaʻa iā ia ka ikaika mechanical kiʻekiʻe a me ka paʻakikī kiʻekiʻe. Ua hana pū kekahi poʻe noiʻi i ʻekolu mau ʻano prepolymers NIPU me nā hui hope furan ma o ka pane wehe ʻana o ka diethylene glycol bicyclic carbonate a me ka diamine, a laila hana ʻia me ka polyester unsaturated e hoʻomākaukau i ka polyurethane palupalu me ka hana hoʻōla ponoʻī, a ua ʻike maikaʻi i ka pono o ka hoʻōla ponoʻī kiʻekiʻe o ka NIPU palupalu. ʻAʻole ʻo Hybrid NIPU wale nō nā hiʻohiʻona o ka NIPU maʻamau, akā ʻoi aku ka maikaʻi o ka hoʻopili ʻana, ka ʻakika a me ka pale ʻana i ka corrosion alkali, ka pale pale a me ka ikaika mechanical.
3 Nānā
Hoʻomākaukau ʻia ʻo NIPU me ka ʻole o ka hoʻohana ʻana i ka isocyanate toxic, a ke aʻo ʻia nei i kēia manawa ma ke ʻano o ka foam, coating, adhesive, elastomer a me nā huahana ʻē aʻe. Eia nō naʻe, ʻo ka hapa nui o lākou e kaupalena ʻia i ka noiʻi keʻena hana, a ʻaʻohe hana nui. Eia kekahi, me ka hoʻomaikaʻi ʻana i nā kūlana ola o nā kānaka a me ka ulu mau ʻana o ka noi, ua lilo ʻo NIPU me ka hana hoʻokahi a i ʻole nā hana he nui i alakaʻi noiʻi koʻikoʻi, e like me ka antibacterial, hoʻoponopono ponoʻī, hoʻomanaʻo hoʻomanaʻo, pale ahi, pale wela kiʻekiʻe a pēlā aku. No laila, pono e ʻike ka noiʻi e hiki mai ana i ka wā e wāwahi ai i nā pilikia koʻikoʻi o ka ʻenehana a hoʻomau i ka ʻimi ʻana i ke ala o ka hoʻomākaukau ʻana i ka NIPU hana.
Ka manawa hoʻouna: ʻAukake-29-2024