Ci gaban Bincike akan Non-Isocyanate Polyurethanes
Tun lokacin da aka gabatar da su a cikin 1937, kayan polyurethane (PU) sun sami aikace-aikace masu yawa a sassa daban-daban ciki har da sufuri, gini, kayan aikin petrochemicals, yadi, injiniyan injiniya da lantarki, sararin samaniya, kiwon lafiya, da noma. Ana amfani da waɗannan kayan a cikin nau'o'i irin su filastik kumfa, fibers, elastomers, abubuwan hana ruwa, fata na roba, sutura, manne, kayan shimfidawa da kayan aikin likita. PU na al'ada an haɗa shi da farko daga isocyanates biyu ko fiye tare da polyols macromolecular da ƙananan sarkar kwayoyin halitta. Duk da haka, abubuwan da ke tattare da guba na isocyanates suna haifar da haɗari ga lafiyar ɗan adam da muhalli; Bugu da ƙari, yawanci ana samo su ne daga phosgene-wani abu mai guba sosai-da kuma daidaitaccen kayan amine.
Dangane da kokarin masana'antar sinadarai na zamani na neman kore da ayyukan ci gaba mai dorewa, masu bincike suna ƙara mai da hankali kan maye gurbin isocyanates tare da albarkatu masu dacewa da muhalli yayin da suke binciko hanyoyin haɗin kai don waɗanda ba na isocyanate polyurethanes (NIPU). Wannan takarda ta gabatar da hanyoyin shirye-shiryen don NIPU yayin nazarin ci gaba a cikin nau'o'in NIPU daban-daban da kuma tattaunawa game da makomar su na gaba don samar da tunani don ƙarin bincike.
1 Haɗin kai na Polyurethanes marasa Isocyanate
Haɗin farko na ƙananan ƙwayoyin carbamate mahadi ta amfani da monocyclic carbonates haɗe tare da diamines aliphatic ya faru a ƙasashen waje a cikin 1950s-alama wani lokaci mai mahimmanci ga haɗin polyurethane mara isocyanate. A halin yanzu akwai hanyoyi guda biyu na farko don samar da NIPU: Na farko ya haɗa da haɓaka haɓakar haɓakawa ta mataki-mataki tsakanin carbonates cyclic da binary amines; na biyu ya haɗa da halayen daɗaɗɗa da ke tattare da diurethane tsaka-tsaki tare da diols waɗanda ke sauƙaƙe mu'amalar tsarin a cikin carbamate. Ana iya samun matsakaicin dimarboxylate ta hanyar ko dai carbonate cyclic ko dimethyl carbonate (DMC); Ainihin duk hanyoyin suna amsawa ta hanyar ƙungiyoyin carbonic acid waɗanda ke haifar da ayyukan carbamate.
Sassan da ke gaba sun yi bayani dalla-dalla kan hanyoyi daban-daban guda uku don haɗa polyurethane ba tare da amfani da isocyanate ba.
1.1 Hanyar Carbonate Binary Cyclic
Ana iya haɗe NIPU ta hanyar ƙari na mataki-mataki wanda ya haɗa da binary cyclic carbonate haɗe tare da amine na binary kamar yadda aka kwatanta a hoto 1.
Saboda ƙungiyoyin hydroxyl da yawa da ke cikin maimaita raka'a tare da babban tsarin sarkar sa wannan hanyar gabaɗaya tana haifar da abin da ake kira polyβ-hydroxyl polyurethane (PHU). Leitsch et al., Haɓaka jerin polyether PHUs suna amfani da cyclic carbonate-terminated polyethers tare da amines binary tare da ƙananan ƙwayoyin da aka samo daga binary cyclic carbonates - kwatankwacin waɗannan da hanyoyin gargajiya da ake amfani da su don shirya polyether PUs. Binciken su ya nuna cewa ƙungiyoyin hydroxyl a cikin PHUs suna samar da haɗin gwiwar hydrogen tare da nitrogen / oxygen atom wanda ke cikin sassa masu laushi / wuya; Bambance-bambance tsakanin sassa masu laushi kuma suna yin tasiri ga halayen haɗin gwiwar hydrogen da kuma digiri na rabuwa na microphase wanda daga baya ya shafi halayen aikin gabaɗayan.
Yawanci ana gudanar da shi a ƙasa da yanayin zafi sama da 100 ° C wannan hanyar ba ta haifar da samfurori ba yayin tafiyar matakai da ke sanya shi rashin jin daɗi ga danshi yayin samar da samfuran barga waɗanda ba su da damuwa na rashin ƙarfi duk da haka yana buƙatar kaushi mai ƙarfi wanda ke da ƙarfi kamar dimethyl sulfoxide (DMSO), N, N-dimethylformamide (DMF), da dai sauransu .. Bugu da ƙari, tsawaita lokacin amsawa daga ko'ina tsakanin rana ɗaya har zuwa kwanaki biyar sau da yawa yana haifar da ƙananan ma'aunin ƙwayoyin cuta akai-akai yana faɗuwa ƙasa ƙasa da 30k g / mol yana ba da babban sikelin samar da ƙalubale saboda an danganta shi da babban farashi. Haɗe a ciki haɗe da ƙarancin ƙarfin da aka nuna ta sakamakon PHUs duk da aikace-aikacen da aka yi alƙawarin da ke tattare da yanki na kayan abu suna siffata ƙwaƙwalwar ajiya tana gina ƙirar mannewa ta hanyar warware kumfa da sauransu.
1.2 Hanyar Carbonate Monocylic
Monocylic carbonate yana amsawa kai tsaye tare da diamine sakamakon dicarbamate yana da ƙungiyoyin ƙarshe na hydroxyl waɗanda sannan ana yin hulɗar transesterification / polycondensation na musamman tare da diols a ƙarshe suna haifar da takwarorinsu na gargajiya na NIPU da aka kwatanta da gani ta Hoto 2.
Bambance-bambancen monocylic da aka saba amfani da su sun haɗa da ethylene & propylene carbonated substrates inda ƙungiyar Zhao Jingbo a Jami'ar Kimiyya ta Jami'ar Beijing ta tsunduma cikin nau'ikan diamines daban-daban waɗanda ke mayar da martani ga ƙungiyoyin cyclical da farko sun sami bambance-bambancen tsarin dicarbamate na tsaka-tsaki kafin a ci gaba da aiwatar da matakan hana ruwa ta hanyar amfani da ko dai polytetradioldiolyedolyel. Layukan samfur daban-daban waɗanda ke nuna kyawawan kaddarorin thermal / injiniyoyi suna kaiwa sama zuwa wuraren narkewa suna shawagi a kusa da kewayon haɓaka kusan 125 ~ 161 ° C ƙarfin ƙarfin ƙarfi kusa da 24MPa ƙimar elongation kusa da 1476%. Wang et al., Hakazalika haɗe-haɗe da aka haɗa wanda ya ƙunshi DMC wanda aka haɗa bi da bi w/hexamethylenediamine/ cyclocarbonated precursors synthesizing hydroxy-terminated derivatives daga baya sa biobased dibasic acid kamar oxalic/sebacic/acids adipic-acid-terephtalics cimma sakamako na ƙarshe ~ nuna kewayon Ƙarfin ƙarfi yana canzawa9 ~ 17 MPa elongations daban-daban 35% ~ 235%.
Cyclocarbonic esters suna aiki yadda ya kamata ba tare da buƙatar masu haɓakawa a ƙarƙashin yanayi na yau da kullun suna kiyaye zafin jiki kusan 80 ° zuwa 120 ° C na gaba transesterifications yawanci suna amfani da tsarin kayyade na tushen organotin wanda ke tabbatar da ingantaccen aiki ba zai wuce 200 ° ba. Bayan ƙoƙarce-ƙoƙarce kawai da ke niyya abubuwan shigar da diolic waɗanda ke da ikon sarrafa kai/deglycolysis abubuwan da ke sauƙaƙe tsarar da ake so sakamakon da ake so yana haifar da hanyoyin da ke da alaƙa da yanayin muhalli galibi suna samar da ragowar methanol/kananan-kwayar-kwayoyin-diolic don haka yana gabatar da madaidaitan hanyoyin masana'antu suna ci gaba.
1.3 Dimethyl Carbonate Hanyar
DMC tana wakiltar wani zaɓi mai sauti / mara guba mai guba wanda ke nuna nau'ikan ayyuka masu yawa waɗanda suka haɗa da saitunan methyl/methoxy/carbonyl waɗanda ke haɓaka bayanan martaba waɗanda ke ba da damar haɗin gwiwa na farko wanda DMC ke hulɗa kai tsaye tare da diamines waɗanda ke haifar da ƙarami na methyl-carbamate ƙarewar tsaka-tsakin da ke biyo baya bayan narkar da ayyukan haɗakarwa. ƙarin ƙananan sarka-extender-diolics/mafi girma-polyol abubuwan da ke haifar da fitowar ƙarshe da ake nema-bayan tsarin polymer wanda aka gani daidai ta hanyar Hoto3.
Deepa et.al yayi girma akan abubuwan da aka ambata a baya suna ba da damar haɓakar sodium methoxide catalysis orchestrating bambance-bambancen tsaka-tsaki na tsaka-tsaki daga baya yin haɓaka haɓakar haɓakar da aka yi niyya wanda ya ƙare jerin daidaitattun nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan kwayoyin halitta (3 ~ 20) x10 ^ 3g / molning gilashin canji 0. °C). Pan Dongdong ya zaɓi nau'ikan dabarun dabaru wanda ya ƙunshi DMC hexamethylene-diaminopolycarbonate-polyalcohols yana fahimtar sakamako masu ban mamaki da ke nuna ma'aunin ƙarfi-ƙarfi oscillating10-15MPa ƙimar elongation yana gabatowa1000%-1400%. Binciken binciken da ke tattare da tasirin sarkar-tsara daban-daban ya nuna fifikon dacewa da daidaita zaɓin butanediol/hexanediol lokacin da adadin atomic-lambar ya ci gaba da haɓaka haɓakar haɓakar kristal da aka ba da umarni a cikin sarƙoƙi. .Ƙarin bincike da nufin deriving non-isocyant-polyureas leveraging diazomonomer alkawari tsammanin yuwuwar aikace-aikacen fenti da ke haifar da fa'ida a kan takwarorinsu na vinyl-carbonaceous da ke nuna tasiri-tasiri/ hanyoyin samun riba mai fa'ida.Tsarin ƙwazo game da ƙayyadaddun ƙayyadaddun hanyoyin haɓakawa da haɓaka yanayin haɓakawa yawanci. ƙin buƙatun ƙaushi don haka rage magudanan sharar gida galibi suna iyakance kawai methanol/kananan-kwayoyin-diolic effluents waɗanda ke tabbatar da haɓakar halayen kore gabaɗaya.
2 sassa daban-daban masu laushi na polyurethane ba isocyanate
2.1 polyether polyurethane
Polyether polyurethane (PEU) ana amfani dashi sosai saboda ƙarancin ƙarfin haɗin kai na ether bond a cikin sassa mai laushi mai maimaita raka'a, jujjuya mai sauƙi, kyakkyawan yanayin yanayin zafi da juriya na hydrolysis.
Kebir et al. hada polyether polyurethane tare da DMC, polyethylene glycol da butanediol a matsayin albarkatun kasa, amma kwayoyin nauyi ne low (7 500 ~ 14 800g / mol), Tg ya kasa da 0 ℃, da kuma narkewa batu ne ma low (38 ~ 48 ℃) , kuma ƙarfin da sauran alamun sun kasance masu wahala don biyan bukatun amfani. Ƙungiyar bincike ta Zhao Jingbo ta yi amfani da ethylene carbonate, 1, 6-hexanediamine da polyethylene glycol don haɗa PEU, wanda ke da nauyin kwayoyin halitta na 31 000g / mol, ƙarfin ƙarfin 5 ~ 24MPa, da elongation a karya na 0.9% ~ 1 388%. A kwayoyin nauyi na hada jerin aromatic polyurethanes ne 17 300 ~ 21 000g / mol, da Tg ne -19 ~ 10 ℃, da narkewa batu ne 102 ~ 110 ℃, da tensile ƙarfi ne 12 ~ 38MPa, da kuma na roba dawo da kudi. na 200% m elongation ne 69% ~ 89%.
Ƙungiyar bincike na Zheng Liuchun da Li Chuncheng sun shirya tsaka-tsakin 1, 6-hexamethylenediamine (BHC) tare da dimethyl carbonate da 1, 6-hexamethylenediamine, da polycondensation tare da ƙananan ƙananan kwayoyin halitta madaidaiciya sarkar diols da polytetrahydrofuranediols (Mn = 2 000). An shirya jerin nau'in polyether polyurethane (NIPEU) tare da hanyar da ba ta isocyanate ba, kuma an warware matsalar ƙetare na tsaka-tsaki a lokacin amsawa. An kwatanta tsarin da kaddarorin polyether polyurethane na gargajiya (HDIPU) wanda NIPEU da 1, 6-hexamethylene diisocyanate suka shirya, kamar yadda aka nuna a cikin Table 1.
| Misali | Kashi mai wuyar kashi/% | Nauyin kwayoyin halitta/(g·mol^(-1)) | Fihirisar rarraba nauyin kwayoyin halitta | Ƙarfin ƙarfi / MPa | Tsawaitawa a lokacin hutu /% |
| 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 |
Tebur 1
Sakamako a cikin Table 1 ya nuna cewa bambance-bambancen tsarin tsakanin NIPEU da HDIPU sun fi girma saboda sashi mai wuyar gaske. Rukunin urea da ke haifar da martani na gefe na NIPEU an shigar da shi ba tare da izini ba a cikin sarkar sassan kwayoyin halitta mai wuya, yana karya yanki mai wuya don samar da haɗin gwiwar hydrogen da aka ba da umarni, yana haifar da raunin haɗin gwiwar hydrogen tsakanin sassan kwayoyin halitta na ɓangaren mai wuya da ƙarancin crystallinity na ɓangaren mai wuya. , yana haifar da ƙarancin rabuwa na NIPEU. A sakamakon haka, kayan aikin injin sa sun fi HDIPU muni.
2.2 Polyester Polyurethane
Polyester polyurethane (PETU) tare da polyester diols a matsayin sassa mai laushi yana da kyakkyawan biodegradability, biocompatibility da kayan aikin injiniya, kuma za'a iya amfani dashi don shirya kayan aikin injiniya na nama, wanda shine kayan aikin ilimin halitta tare da babban damar aikace-aikacen. Polyester diols da aka saba amfani da su a cikin sassa masu laushi sune polybutylene adipate diol, polyglycol adipate diol da polycaprolactone diol.
Tun da farko, Rokicki et al. amsa ethylene carbonate tare da diamine da diols daban-daban (1, 6-hexanediol,1, 10-n-dodecanol) don samun NIPU daban-daban, amma NIPU da aka haɗa yana da ƙananan nauyin kwayoyin da ƙananan Tg. Farhadian et al. shirya polycyclic carbonate ta amfani da sunflower iri man a matsayin albarkatun kasa, sa'an nan gauraye da bio-tushen polyamines, mai rufi a kan farantin, da kuma warke a 90 ℃ for 24 h don samun thermosetting polyester polyurethane film, wanda ya nuna mai kyau thermal kwanciyar hankali. Rukunin bincike na Zhang Liqun na Jami'ar Fasaha ta Kudancin kasar Sin sun hada nau'ikan diamines da carbonates na cyclic, sa'an nan kuma an sanya su tare da dibasic acid na biobased don samun polyester polyurethane na biobased. Rukunin bincike na Zhu Jin a Cibiyar Nazarin Kayan Aiki ta Ningbo, Cibiyar Nazarin Kimiyya ta kasar Sin ta shirya wani yanki mai wuya na diaminodiol ta amfani da hexadiamine da vinyl carbonate, sa'an nan polycondensation tare da bio-based unsaturated dibasic acid don samun jerin polyester polyurethane, wanda za a iya amfani da matsayin fenti bayan. maganin ultraviolet [23]. Rukunin bincike na Zheng Liuchun da Li Chuncheng sun yi amfani da adipic acid da diols aliphatic hudu (butanediol, hexadiol, octanediol da decanediol) tare da lambobi daban-daban na carbon atomic don shirya daidaitattun polyester diols a matsayin sassa masu laushi; Ƙungiya na polyester polyurethane (PETU), mai suna bayan adadin carbon atom na diols aliphatic, an samo shi ta hanyar narkewar polycondensation tare da nau'i na hydroxy-sealed hard segment prepolymer wanda BHC da diols suka shirya. Ana nuna kaddarorin injiniyoyi na PETU a cikin Table 2.
| Misali | Ƙarfin ƙarfi / MPa | Na roba modules/MPa | Tsawaitawa a lokacin hutu /% |
| 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 |
Table 2
Sakamakon ya nuna cewa ɓangaren laushi na PETU4 yana da mafi girman nauyin carbonyl, mafi ƙarfin hydrogen bond tare da sashi mai wuya, kuma mafi ƙanƙanci matakin rabuwa. Ƙaƙƙarfan ƙira na duka sassa masu laushi da wuyar gaske yana da iyaka, yana nuna ƙarancin narkewa da ƙarfi, amma mafi girman elongation a karya.
2.3 polycarbonate polyurethane
Polycarbonate polyurethane (PCU), musamman aliphatic PCU, yana da kyakkyawan juriya na hydrolysis, juriya na iskar shaka, kyakkyawan kwanciyar hankali na ilimin halitta da haɓakar halittu, kuma yana da kyakkyawar damar aikace-aikacen a fagen biomedicine. A halin yanzu, yawancin NIPU da aka shirya suna amfani da polyether polyols da polyester polyols a matsayin sassa masu laushi, kuma akwai 'yan rahotanni na bincike akan polycarbonate polyurethane.
Polyurethane wanda ba na isocyanate polycarbonate da ƙungiyar Tian Hengshui ta shirya a Jami'ar Fasaha ta Kudancin China yana da nauyin kwayoyin fiye da 50 000 g / mol. An yi nazarin tasirin yanayin amsawa akan nauyin kwayoyin halitta na polymer, amma ba a ba da rahoton kaddarorin aikin sa ba. Zheng Liuchun da ƙungiyar bincike ta Li Chuncheng sun shirya PCU ta amfani da DMC, hexanediamine, hexadiol da polycarbonate diols, kuma suna PCU bisa ga babban juzu'in juzu'i mai maimaita juzu'i. Ana nuna kaddarorin injiniyoyi a cikin Tebur 3.
| Misali | Ƙarfin ƙarfi / MPa | Na roba modules/MPa | Tsawaitawa a lokacin hutu /% |
| 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 |
Table 3
Sakamakon ya nuna cewa PCU yana da nauyin kwayoyin halitta mai girma, har zuwa 6 × 104 ~ 9 × 104g / mol, ma'anar narkewa har zuwa 137 ℃, da ƙarfin ƙarfi har zuwa 29 MPa. Ana iya amfani da irin wannan nau'in PCU ko dai azaman filastik mai tsauri ko azaman elastomer, wanda ke da kyakkyawan fata na aikace-aikacen a fagen ilimin halittu (kamar injinan nama na jikin ɗan adam ko kayan dasawa na zuciya).
2.4 Hybrid polyurethane maras isocyanate
Hybrid non-isocyanate polyurethane ( hybrid NIPU) shine gabatarwar resin epoxy, acrylate, silica ko siloxane kungiyoyin a cikin tsarin kwayoyin polyurethane don samar da hanyar sadarwa ta hanyar sadarwa, inganta aikin polyurethane ko ba da polyurethane ayyuka daban-daban.
Feng Yuelan et al. reacted bio-based epoxy soybean man fetur tare da CO2 don haɗa pentamonic cyclic carbonate (CSBO), kuma ya gabatar da bisphenol A diglycidyl ether (epoxy resin E51) tare da ƙarin sassan sarkar sarkar don ƙara haɓaka NIPU da CSBO ta kafa tare da amine. Sarkar kwayoyin halitta tana ƙunshe da sashin sarkar mai sassauƙa mai tsayi na oleic acid/linoleic acid. Hakanan yana ƙunshe da ƙarin sassan sarƙaƙƙiya masu tsauri, don yana da ƙarfin injina da ƙarfi mai ƙarfi. Wasu masu binciken kuma sun haɗa nau'ikan nau'ikan NIPU prepolymers guda uku tare da ƙungiyoyin ƙarshen bude ta hanyar haɓaka ƙimar diethylene glycol bicyclic carbonate da diamine, sannan suka amsa tare da polyester mara kyau don shirya polyurethane mai laushi tare da aikin warkar da kai, kuma sun sami nasarar gane babban kai. -warkar da ingantaccen NIPU mai laushi. Hybrid NIPU ba wai kawai yana da halayen NIPU gabaɗaya ba, har ma yana iya samun mafi kyawun mannewa, juriya na lalata acid da alkali, juriya mai ƙarfi da ƙarfin injina.
3 Outlook
An shirya NIPU ba tare da amfani da isocyanate mai guba ba, kuma a halin yanzu ana nazarin a cikin nau'i na kumfa, sutura, m, elastomer da sauran samfurori, kuma yana da nau'i mai yawa na aikace-aikace. Duk da haka, yawancin su har yanzu suna iyakance ga binciken dakin gwaje-gwaje, kuma babu wani babban abin samarwa. Bugu da ƙari, tare da inganta yanayin rayuwar mutane da ci gaba da ci gaba da buƙata, NIPU tare da aiki guda ɗaya ko ayyuka masu yawa ya zama jagorar bincike mai mahimmanci, irin su antibacterial, gyaran gyare-gyaren kai, ƙwaƙwalwar siffar, ƙwaƙwalwar wuta, rashin ƙarfi mai zafi da kuma juriya na zafi. haka kuma. Sabili da haka, ya kamata bincike na gaba ya fahimci yadda za a warware manyan matsalolin masana'antu da kuma ci gaba da gano alkiblar shirya NIPU mai aiki.
Lokacin aikawa: Agusta-29-2024