Horumarka Cilmi-baarista ee Polyurethanes-ka Aan Isocyanate ahayn
Tan iyo markii la soo bandhigay 1937, agabka polyurethane (PU) wuxuu helay codsiyo ballaaran oo ku baahsan qaybaha kala duwan oo ay ku jiraan gaadiidka, dhismaha, kiimikada batroolka, dharka, injineernimada farsamada iyo korontada, hawada sare, daryeelka caafimaadka, iyo beeraha. Agabkan waxaa loo isticmaalaa qaabab sida balaastikada xumbo, fiilooyinka, elastomers, wakiilada biyaha celiya, maqaar macmal ah, dahaarka, dhejiska, agabka laamiga iyo agabka caafimaadka. PU-ga dhaqameed waxaa inta badan laga sameeyaa laba ama in ka badan isocyanates oo ay weheliso polyols macromolecular iyo fidiyeyaasha silsiladda molecular-ka yar yar. Si kastaba ha ahaatee, sunta ku jirta isocyanates waxay khataro waaweyn ku tahay caafimaadka aadanaha iyo deegaanka; waxaa kaloo badanaa laga helaa phosgene - oo ah horudhac aad u sun ah - iyo agabyada ceeriin ee amine ee u dhigma.
Marka la eego raadinta warshadaha kiimikada ee casriga ah ee dhaqamada horumarinta cagaaran iyo kuwa waara, cilmi-baarayaashu waxay si isa soo taraysa diiradda u saarayaan inay ku beddelaan isocyanates ilo deegaanka u fiican iyagoo sahaminaya dariiqooyin cusub oo isku-darka polyurethanes-ka aan isocyanate ahayn (NIPU). Warqaddani waxay soo bandhigaysaa waddooyinka diyaarinta ee NIPU iyadoo dib u eegaysa horumarka noocyada kala duwan ee NIPUs iyo ka wada hadalka mustaqbalkooda si ay u bixiyaan tixraac cilmi-baaris dheeraad ah.
1 Isku-darka Polyurethanes-ka Aan Isocyanate ahayn
Isku-darka ugu horreeya ee isku-darka karbomate-ka miisaanka yar ee molecular-ka iyadoo la adeegsanayo monocyclic carbonates oo lagu daray aliphatic diamines ayaa ka dhacay dibadda sannadihii 1950-meeyadii - taasoo calaamad u ah daqiiqad muhiim u ah isku-darka polyurethane-ka aan isocyanate ahayn. Hadda waxaa jira laba hab oo aasaasi ah oo lagu soo saarayo NIPU: Tan koowaad waxay ku lug leedahay falcelinta isku-darka tallaabo-tallaabo ah oo u dhexeeya karbonat-ka wareegga laba-geesoodka ah iyo amines-ka laba-geesoodka ah; tan labaad waxay ku lug leedahay falcelinta polycondensation oo ku lug leh dhexdhexaadiyeyaasha diurethane oo ay weheliyaan diols kuwaas oo fududeeya is-weydaarsiga qaab-dhismeedka gudaha carbamates. Dhexdhexaadiyeyaasha diamarboxylate waxaa laga heli karaa marinnada carbonate-ka wareegga ama dimethyl carbonate (DMC); asal ahaan dhammaan hababka waxay ka falceliyaan kooxaha aashitada kaarboon ee soo saara shaqooyinka carbamate.
Qaybaha soo socdaa waxay faahfaahin ka bixinayaan saddex hab oo kala duwan oo loo sameeyo polyurethane iyada oo aan la isticmaalin isocyanate.
1.1 Wadada Kaarboonatka Wareegsan ee Binary Cyclic
NIPU waxaa lagu samayn karaa iyada oo loo marayo ku darid tallaabo tallaabo ah oo ku lug leh laba-geesoodka carbonate-ka wareegga ah oo ay weheliso binary amine sida ku cad Jaantuska 1.
Sababo la xiriira kooxo badan oo hydroxyl ah oo ku jira cutubyo soo noqnoqda oo ku yaal qaab-dhismeedka silsiladda ugu weyn, habkani wuxuu guud ahaan soo saaraa waxa loogu yeero polyβ-hydroxyl polyurethane (PHU). Leitsch et al., waxay sameeyeen taxane ah PHU-yada polyether oo adeegsanaya polyether-ka carbonate-ka ee la joojiyay oo ay weheliyaan amiin binary ah iyo molecules yar yar oo laga soo qaatay carbonates-ka binary cyclic - iyagoo isbarbar dhigaya hababka dhaqameed ee loo isticmaalo diyaarinta polyether PUs. Natiijooyinkoodu waxay muujiyeen in kooxaha hydroxyl ee ku jira PHU-yada ay si fudud u sameeyaan xiriirro hydrogen ah oo leh atamka nitrogen/oxygen ee ku yaal qaybaha jilicsan/adag; kala duwanaanshaha qaybaha jilicsan ayaa sidoo kale saameeya dhaqanka isku xidhka hydrogen iyo sidoo kale heerarka kala-soocidda microphase kuwaas oo markaa saameeya sifooyinka waxqabadka guud.
Caadi ahaan waxaa lagu sameeyaa heerkul ka hooseeya 100 °C wadadani ma keento wax soo saar ka baxsan inta lagu jiro hababka falcelinta taasoo ka dhigaysa mid aan xasaasiyad u lahayn qoyaanka iyadoo soo saaraysa alaabooyin deggan oo aan lahayn walaac isbeddel ah laakiin waxaa lagama maarmaan ah dareereyaal dabiici ah oo lagu garto polarity xooggan sida dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF), iwm. Intaa waxaa dheer, waqtiyada falcelinta ee la dheereeyey oo u dhexeeya hal maalin ilaa shan maalmood badanaa waxay keenaan miisaanno molecular oo hooseeya oo inta badan hoos u dhacaya heerarka qiyaastii 30kg/mol taasoo keentay wax soo saar baaxad weyn oo adag sababtoo ah inta badan waxaa loo aaneynayaa labadaba kharashaadka sare ee la xiriira oo ay weheliso xoog aan ku filnayn oo ay muujiyeen PHU-yada ka dhashay inkastoo codsiyada rajo leh ay ku jiraan qaybaha walxaha ee qoyaanka qaabaynta qaabaynta xusuusta qaababka dahaarka xalalka dahaarka iwm.
1.2 Wadada Kaarboonat-ka ee Monocylic
Monocylic carbonate waxay si toos ah ula falgashaa dicarbamate-ka ka dhasha diamine oo leh kooxo dhammaad hydroxyl ah kuwaas oo markaa mara is-dhexgal gaar ah oo transesterification/polycondensation ah oo ay weheliyaan diols ugu dambeyntii soo saara NIPU oo qaab-dhismeed ahaan la mid ah kuwa dhaqameed ee lagu sawiray Jaantuska 2aad.
Noocyada monocylic ee caadiga ah ee la isticmaalo waxaa ka mid ah substrate-yada kaarboonaysan ee ethylene & propylene halkaas oo kooxda Zhao Jingbo ee Jaamacadda Tiknoolajiyadda Kiimikada ee Beijing ay ku hawlan yihiin diamines kala duwan oo ka falcelinaya hay'adaha wareegga ah iyagoo markii hore helay dhexdhexaadiyayaal qaab-dhismeed oo kala duwan oo dicarbamate ah ka hor inta aysan u gudbin marxaladaha uumiga iyagoo adeegsanaya midkood polytetrahydrofuranediol/polyether-diols taasoo keentay sameynta guul leh khadadka badeecadaha ee soo bandhigaya sifooyin kuleyl/farsamo oo cajiib ah oo gaaraya dhibco dhalaal ah oo kor u kacaya oo ku wareegsan baaxadda oo ku fidsan qiyaastii 125 ~ 161°C oo u dhow heerarka fidinta 24MPa oo ku dhow 1476%. Wang et al., isku-darka la isku daray ee ka kooban DMC oo si isku mid ah loogu lammaaneeyay hexamethylenediamine/cyclocarbonated presectors oo isku daraya derivatives-ka hydroxy-endated derivatives ka dib markii la mariyey bayoolaji ahaan asiidhyada dibasic sida oxalic/sebacic/acids adipic-acid-terephthalics oo gaaraya natiijooyin kama dambays ah oo muujinaya heerarka oo ka kooban 13k~28kg/mol awoodaha la jiido oo isbeddelaya9~17 MPa oo dheeraanaya oo kala duwan35%~235%.
Esters-ka Cyclocarbonic waxay si wax ku ool ah ula falgalaan iyagoon u baahnayn kiciyeyaasha xaaladaha caadiga ah iyagoo ilaalinaya heerkulka u dhexeeya 80° ilaa 120°C transesterifications-ka xiga waxay badanaa adeegsadaan nidaamyada catalytic-ka ku salaysan organotin iyagoo hubinaya in habaynta ugu fiican aysan ka badnayn 200°. Ka sokow dadaallada kaliya ee uumiga ah ee lagu beegsanayo wax soo saarka diolic, kuwaas oo awood u leh is-polymerization/deglycolysis, fududaynta natiijooyinka la rabo ee la rabo waxay ka dhigaysaa habka mid dabiici ah oo deegaanka u fiican oo inta badan soo saara haraaga methanol/molecule-yar-diolic sidaas darteedna soo bandhigaya beddello warshadeed oo suurtagal ah oo mustaqbalka socda.
Wadada 1.3Dimethyl Carbonate
DMC waxay matalaysaa beddel deegaan ahaan u fiican/aan sun ahayn oo leh qaybo badan oo firfircoon oo shaqeynaya oo ay ku jiraan habaynta methyl/methoxy/carbonyl oo kor u qaadaya astaamaha fal-celinta si weyn u suurtagelinaya hawlgallada bilowga ah halkaas oo DMC si toos ah ula falgasho diamines iyadoo sameysanaya dhexdhexaadiyayaal yar yar oo methyl-carbamate ah oo la joojiyay ka dibna ka dib ficillada dhalaalka-isku-darka oo ay ku jiraan qaybo dheeraad ah oo silsilad yar-fidsan-diolics/polyol waaweyn ah oo horseedda soo ifbaxa ugu dambeeya ee qaab-dhismeedka polymer-ka ee la raadiyay iyadoo loo marayo Jaantuska 3.
Deepa et.al waxay ku faa'iidaysatay dhaqdhaqaaqyada kor ku xusan iyadoo la adeegsanayo katalisyada sodium methoxide oo abaabulaya qaabab kala duwan oo dhexdhexaad ah ka dibna ku lug leh fidinta bartilmaameedka ah oo ugu dambayntii isku-darka qaybaha adag ee isku midka ah oo gaaraya miisaanno molecular ah oo qiyaastii ah (3 ~20) x10^3g/mol heerkulka kala-guurka galaaska oo soconaya (-30 ~120°C). Pan Dongdong wuxuu doortay isku-xidhka istaraatiijiyadeed ee ka kooban DMC hexamethylene-diaminopolycarbonate-polyalcohols oo gaadhay natiijooyin la taaban karo oo muujinaya cabbirro xoog leh oo isbedbeddelaya 10-15MPa saamiga fidinta oo ku dhow 1000%-1400%. Dadaallo baaritaan oo ku saabsan saameynta kala duwan ee silsiladda fidinta ayaa muujiyay doorbidyada si wanaagsan u waafajinaya xulashooyinka butanediol/hexanediol marka sinnaanta tirada atomiga ay ilaaliso sinnaanta kor u qaadista horumarinta kristalinta nidaamsan ee lagu arkay silsiladaha oo dhan. Kooxda Sarazin waxay diyaarisay isku-darka isku-dhafka ah ee isku daraya lignin/DMC oo ay weheliso hexahydroxyamine oo muujinaya sifooyin farsamo oo qanciya ka dib farsamaynta 230℃. Sahamin dheeraad ah oo loogu talagalay in la helo kuwa aan isocyante-polyureas ahayn oo ka faa'iideysanaya ka-qaybgalka diazomonomer ayaa la filayaa codsiyada rinjiga ee suurtagalka ah ee soo baxaya faa'iidooyin isbarbardhig ah oo ka badan kuwa kale ee vinyl-ka kaarboonka ah oo muujinaya kharash-oolnimada/waddooyinka ka-soo-saarka ballaaran ee la heli karo. Dadaalka saxda ah ee ku saabsan hababka isku-darka badan ayaa badanaa u baahan jawi heerkul sarreeya/vacuum ah oo ka hortagaya shuruudaha dareeraha taasoo yaraynaysa qulqulka qashinka oo inta badan xaddidan oo keliya methanol/molecule-yar-diolic oo sameeya qaababka isku-dhafka cagaaran guud ahaan.
2 Qaybood oo jilicsan oo kala duwan oo ah polyurethane aan isocyanate ahayn
2.1 Polyether polyurethane
Polyether polyurethane (PEU) si weyn ayaa loo isticmaalaa sababtoo ah tamar isku-xidhnaan hoose oo ka timaadda isku-xidhka ether ee cutubyada ku celcelinta qaybaha jilicsan, wareeg fudud, dabacsanaan heerkul hooseeya oo aad u fiican iyo iska caabinta hydrolysis.
Kebir iyo asxaabtiisa waxay sameeyeen polyether polyurethane oo leh DMC, polyethylene glycol iyo butanediol oo ah walxo ceeriin ah, laakiin miisaanka molecular-ka wuu hooseeyay (7 500 ~ 14 800g/mol), Tg wuxuu ka hooseeyay 0℃, barta dhalaalkuna sidoo kale way hooseysay (38 ~ 48℃), xoogga iyo tilmaamayaasha kale way adkeyd in la daboolo baahiyaha isticmaalka. Kooxda cilmi-baarista ee Zhao Jingbo waxay adeegsadeen ethylene carbonate, 1, 6-hexanediamine iyo polyethylene glycol si ay u sameeyaan PEU, oo leh miisaan molecular ah oo ah 31 000g/mol, xoog jiidis ah oo ah 5 ~ 24MPa, iyo dheereyn marka jabku yahay 0.9% ~ 1 388%. Miisaanka molecular ee taxanaha la sameeyay ee polyurethanes-ka udgoonka leh waa 17 300 ~ 21 000g/mol, Tg waa -19 ~ 10℃, barta dhalaalku waa 102 ~ 110℃, xoogga jiidista waa 12 ~ 38MPa, heerka soo kabashada laastikada ah ee 200% dheereynta joogtada ah waa 69% ~ 89%.
Kooxda cilmi-baarista ee Zheng Liuchun iyo Li Chuncheng waxay diyaariyeen dhexdhexaadka 1, 6-hexamethylenediamine (BHC) oo leh dimethyl carbonate iyo 1, 6-hexamethylenediamine, iyo polycondensation oo leh molecules yaryar oo kala duwan oo silsilad toosan ah iyo polytetrahydrofuranediols (Mn=2 000). Taxane polyether polyurethanes ah (NIPEU) oo leh waddo aan isocyanate ahayn ayaa la diyaariyey, waxaana la xalliyay dhibaatada isku xidhka ee dhexdhexaadiyeyaasha inta lagu jiro falcelinta. Qaab-dhismeedka iyo sifooyinka polyether polyurethane-ka dhaqameed (HDIPU) oo ay diyaariyeen NIPEU iyo 1, 6-hexamethylene diisocyanate ayaa la barbar dhigay, sida ku cad Shaxda 1.
| Muunad | Jajab cufnaanta qaybta adag/% | Miisaanka molecular/(g)·mol^(-1)) | Tusmada qaybinta miisaanka molecular-ka | Xoogga jiidista/MPa | Kordhinta nasashada/% |
| 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 |
Shaxda 1aad
Natiijooyinka Shaxda 1aad waxay muujinayaan in kala duwanaanshaha qaab-dhismeedka ee u dhexeeya NIPEU iyo HDIPU ay inta badan sabab u tahay qaybta adag. Kooxda urea-da ee ka dhalata falcelinta dhinaca ee NIPEU ayaa si aan kala sooc lahayn ugu dhex milma silsiladda molecular-ka ee qaybta adag, taasoo jebinaysa qaybta adag si ay u samayso xidhmo haydarojiin ah oo nidaamsan, taasoo keentay xidhmo haydarojiin ah oo daciif ah oo u dhexeeya silsiladaha molecular-ka ee qaybta adag iyo kirismaska oo hooseeya ee qaybta adag, taasoo keentay kala-soocid heer hoose ah oo NIPEU ah. Natiijo ahaan, sifooyinkeeda farsamo ayaa aad uga sii daran HDIPU.
2.2 Polyester Polyurethane
Polyester polyurethane (PETU) oo leh polyester diols oo ah qaybo jilicsan ayaa leh bayoolaji wanaagsan, iswaafajin bayooloji iyo sifooyin farsamo, waxaana loo isticmaali karaa in lagu diyaariyo dhismayaasha injineernimada unugyada, taas oo ah walxo bayooloji ah oo leh rajooyin codsi oo wanaagsan. Polyester diols oo badanaa loo isticmaalo qaybaha jilicsan waa polybutylene adipate diol, polyglycol adipate diol iyo polycaprolactone diol.
Horay, Rokicki et al. waxay falceliyeen ethylene carbonate oo leh diamine iyo diols kala duwan (1, 6-hexanediol,1, 10-n-dodecanol) si ay u helaan NIPU kala duwan, laakiin NIPU-ga la sameeyay wuxuu lahaa miisaan molecular oo hooseeya iyo Tg hoose. Farhadian et al. waxay diyaariyeen polycyclic carbonate iyagoo isticmaalaya saliid gabbaldayaha ah sida walxo cayriin ah, ka dibna waxaa lagu qasay polyamines-ka ku salaysan bio, oo lagu dahaadhay saxan, waxaana lagu daaweeyay 90 ℃ muddo 24 saacadood ah si loo helo filim polyester polyester ah oo heerkulkiisu hooseeyo, kaas oo muujiyay xasillooni kuleyl oo wanaagsan. Kooxda cilmi-baarista ee Zhang Liqun oo ka socota Jaamacadda Teknolojiyadda Koonfurta Shiinaha waxay soo saareen taxane diamines iyo carbonates cyclic ah, ka dibna waxaa lagu daray dibasic acid bayooloji ah si loo helo polyester polyurethane bayooloji ah. Kooxda cilmi-baarista ee Zhu Jin ee Machadka Cilmi-baarista Qalabka Ningbo, Akadeemiyada Sayniska Shiinaha waxay diyaarisay qayb adag oo diaminodiol ah iyadoo la adeegsanayo hexadiamine iyo vinyl carbonate, ka dibna polycondensation oo leh dibasic acid aan saturated lahayn oo bayooloji ah si loo helo taxane polyester polyurethane ah, kaas oo loo isticmaali karo rinji ahaan ka dib daaweynta ultraviolet [23]. Kooxda cilmi-baarista ee Zheng Liuchun iyo Li Chuncheng waxay isticmaaleen adipic acid iyo afar aliphatic diols (butanediol, hexadiol, octenediol iyo decanediol) oo leh tirooyin atamiko kaarboon oo kala duwan si ay u diyaariyaan diols-ka polyester-ka ee u dhigma qaybaha jilicsan; Koox ka kooban polyester polyester polyurethane aan isocyanate ahayn (PETU), oo loogu magac daray tirada atamka kaarboon ee diols-ka aliphatic, ayaa la helay iyadoo la dhalaalinayo polycondensation iyadoo la adeegsanayo prepolymer-ka qaybta adag ee hydroxy-sealed oo ay diyaariyeen BHC iyo diols. Sifooyinka farsamada ee PETU waxaa lagu muujiyay Shaxda 2.
| Muunad | Xoogga jiidista/MPa | Modulus-ka dabacsan/MPa | Kordhinta nasashada/% |
| 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 |
Shaxda 2aad
Natiijooyinku waxay muujinayaan in qaybta jilicsan ee PETU4 ay leedahay cufnaanta ugu sarreysa ee kaarboonyl, isku xidhka haydarojiinta ugu xooggan ee qaybta adag, iyo heerka kala-soocidda wejiga ugu hooseeya. Kala-soocidda labada qaybood ee jilicsan iyo kuwa adagba waa xaddidan tahay, taasoo muujinaysa dhibic dhalaalaysa oo hooseysa iyo xoog jiidis, laakiin dheereynta ugu sarreysa marka la kala go'o.
2.3 Polycarbonate polyurethane
Polycarbonate polycarbonate (PCU), gaar ahaan aliphatic PCU, waxay leedahay iska caabin hydrolysis oo aad u fiican, iska caabin oksaydh, xasillooni bayooloji oo wanaagsan iyo iswaafajin bayooloji, waxayna leedahay rajo wanaagsan oo ku saabsan isticmaalka bayomedical. Waqtigan xaadirka ah, inta badan NIPU-da la diyaariyey waxay u isticmaashaa polyether polyols iyo polyester polyols qaybo jilicsan, waxaana jira warbixino cilmi baaris oo yar oo ku saabsan polycarbonate polycarbonate.
Polyurethane-ka polycarbonate-ka aan isocyanate ahayn ee ay diyaarisay kooxda cilmi-baarista ee Tian Hengshui ee Jaamacadda Teknolojiyadda Koonfurta Shiinaha wuxuu leeyahay miisaan molecular ah oo ka badan 50,000 g/mol. Saamaynta xaaladaha falgalka ee miisaanka molecular-ka ee polymer-ka ayaa la bartay, laakiin sifooyinka farsamada lama soo sheegin. Kooxda cilmi-baarista ee Zheng Liuchun iyo Li Chuncheng waxay diyaariyeen PCU iyagoo isticmaalaya DMC, hexanediamine, hexadiol iyo polycarbonate diols, waxayna magacawday PCU iyadoo loo eegayo qaybta tirada badan ee cutubka soo noqnoqda ee qaybta adag. Astaamaha farsamada waxaa lagu muujiyay Shaxda 3.
| Muunad | Xoogga jiidista/MPa | Modulus-ka dabacsan/MPa | Kordhinta nasashada/% |
| 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 |
Shaxda 3aad
Natiijooyinka waxay muujinayaan in PCU uu leeyahay miisaan molecular sare ah, ilaa 6×104 ~ 9×104g/mol, dhibic dhalaalaysa ilaa 137 ℃, iyo xoog jiidis ilaa 29 MPa. Noocan PCU waxaa loo isticmaali karaa balaastig adag ama elastomer, kaas oo leh rajo wanaagsan oo ku saabsan cilmiga bayoolajiga (sida qalabka injineernimada unugyada aadanaha ama qalabka lagu tallaalo wadnaha iyo xididdada dhiigga).
2.4 Polyurethane-ka aan isocyanate ahayn ee isku-dhafan
Polyurethane-ka isku-dhafan ee aan is-isocyanate ahayn (NIPU isku-dhafan) waa soo bandhigidda kooxaha epoxy resin, acrylate, silica ama siloxane ee qaab-dhismeedka molecular-ka polyurethane si loo sameeyo shabakad is-dhexgal ah, loo hagaajiyo waxqabadka polyurethane-ka ama loo siiyo polyurethane shaqooyin kala duwan.
Feng Yuelan et al. waxay falceliyeen saliid soybean epoxy ku salaysan bio-based oo leh CO2 si ay u sameeyaan pentamonic cyclic carbonate (CSBO), waxayna soo bandhigeen bisphenol A diglycidyl ether (epoxy resin E51) oo leh qaybo silsilad adag si loo sii wanaajiyo NIPU oo ay samaysay CSBO oo lagu xoojiyay amine. Silsiladda molecular-ka waxay ka kooban tahay qayb silsilad dabacsan oo dheer oo ah oleic acid/linoleic acid. Waxa kale oo ay ka kooban tahay qaybo silsilad adag oo badan, si ay u yeelato xoog farsamo oo sare iyo adkaysi sare. Cilmi-baarayaal qaar ayaa sidoo kale sameeyay saddex nooc oo ah prepolymers NIPU oo leh kooxo furan iyada oo loo marayo falcelinta furitaanka heerka ee diethylene glycol bicyclic carbonate iyo diamine, ka dibna waxay falceliyeen polyester aan dheregsanayn si ay u diyaariyaan polyurethane jilicsan oo leh shaqo is-bogsiin ah, waxayna si guul leh u ogaadeen hufnaanta is-bogsiinta sare ee NIPU jilicsan. NIPU isku-dhafan ma aha oo kaliya inay leedahay astaamaha NIPU guud, laakiin sidoo kale waxay yeelan kartaa isku-dhejin wanaagsan, iska caabinta daxalka aashitada iyo alkali, iska caabinta dareeraha iyo xoogga farsamada.
3 Aragti
NIPU waxaa la diyaariyaa iyada oo aan la isticmaalin isocyanate sun ah, waxaana hadda lagu darayaa qaab xumbo, dahaadh, dhejis, elastomer iyo badeecooyin kale, waxayna leedahay fursado badan oo lagu dabaqi karo. Si kastaba ha ahaatee, intooda badan wali waxay ku kooban yihiin cilmi-baarista shaybaarka, mana jiraan wax soo saar baaxad weyn. Intaa waxaa dheer, iyadoo la horumarinayo heerarka nolosha dadka iyo kobaca joogtada ah ee baahida, NIPU oo leh hal shaqo ama hawlo badan ayaa noqotay jiho cilmi-baaris oo muhiim ah, sida bakteeriyada dila, is-hagaajinta, xusuusta qaabka, dab-damiska, iska caabbinta kulaylka sare iyo wixii la mid ah. Sidaa darteed, cilmi-baarista mustaqbalka waa inay fahtaa sida looga gudbo dhibaatooyinka muhiimka ah ee warshadaha oo ay sii wadaan sahaminta jihada diyaarinta NIPU shaqeynaya.
Waqtiga boostada: Agoosto-29-2024