Waxa loogu yeeropolyurethanewaa soo gaabinta polyurethane, kaas oo ay sameeyeen falcelinta polyisocyanates iyo polyols, oo ay ku jiraan kooxo badan oo amino ester ah oo soo noqnoqda (- NH-CO-O -) ee silsiladda kelli. Xayawaanka poliurethane ee dhabta ah ee la sameeyay, marka lagu daro kooxda amino ester-ka, waxaa sidoo kale jira kooxo sida HOL iyo biuret. Polyols waxay ka tirsan yihiin molecules silsilad dheer oo leh kooxaha hydroxyl dhamaadka, kuwaas oo loo yaqaan "qaybaha silsiladda jilicsan", halka polyisocyanates loo yaqaan "segments silsilad adag".
Ka mid ah resins-ka poliurethane ee ay soo saaraan qaybaha silsiladaha jilicsan iyo kuwa adag, kaliya boqolkiiba yar ayaa ah esters amino acid, sidaas darteed waxaa laga yaabaa inaanay ku habboonayn in loogu yeero polyurethane. Dareen ballaadhan, polyurethane waa wax lagu daro isocyanate.
Noocyada kala duwan ee isocyyanates waxay la falgalaan xeryahooda polyhydroxy si ay u abuuraan qaabab kala duwan oo polyurethane ah, si ay u helaan qalabyo polymer ah oo leh sifooyin kala duwan, sida caagadaha, caag, dahaarka, fiilooyinka, xabagta, iwm.
Caag polyurethane ah ayaa iska leh nooc gaar ah oo caag ah, kaas oo lagu sameeyo falcelinta polyeter-ka ama polyester-ka isocyanate. Waxaa jira noocyo badan oo ay ugu wacan tahay noocyada kala duwan ee alaabta ceeriin, xaaladaha falcelinta, iyo hababka isku xidhka. Marka loo eego qaab dhismeedka kiimikaad, waxaa jira noocyo polyester iyo polyeter ah, marka laga eego habka farsamaynta, waxaa jira saddex nooc: nooca isku dhafka, nooca shubista, iyo nooca thermoplastic.
Caag polyurethane synthetic ah ayaa guud ahaan lagu farsameeyaa iyada oo ka falcelinaysa polyester toosan ama polyeter leh diisocyanate si ay u sameeyaan prepolymer miisaan yar oo kelli ah, kaas oo markaa lagu sakhiray falcelinta silsiladda fidinta si ay u dhaliso polymer miisaan culus. Ka dib, wakiilada isgoysyada ku habboon ayaa lagu daraa oo la kululeeyaa si loo daaweeyo, oo noqda caag vulcanized ah. Habkan waxa loo yaqaan prepolymerization ama habka laba-tallaabo.
Waxa kale oo suurtagal ah in la isticmaalo hab-hal-tallaabo ah - si toos ah loogu qaso polyester-ka toosan ama polyeter-ka leh diisocyanates, silsiladaha fidsan, iyo wakiilada isku-tallaabta si loo bilaabo fal-celinta oo loo abuuro caag poliurethane ah.
Qaybta A ee molecules TPU waxay ka dhigtaa silsiladaha macromolecular si sahlan loo rogi karo, iyada oo ku siinaysa caag poliurethane leh dabacsanaan wanaagsan, yaraynta barta jilicsan iyo heerka labaad ee kala-guurka ee polymer, iyo yaraynta qallafsanaanta iyo xoogga farsamada. Qeybta B-da waxay xiri doontaa wareegga silsiladaha macromolecular, taasoo keenaysa barta jilicsan iyo heerka labaad ee kala-guurka ee polymer si uu u kordhiyo, taasoo keentay kororka qallafsanaanta iyo xoogga farsamada, iyo hoos u dhaca barti. Iyadoo la hagaajinayo saamiga molar ee u dhexeeya A iyo B, TPUs leh sifooyin farsamo oo kala duwan ayaa la soo saari karaa. Qaab dhismeedka isku-xidhka ah ee TPU waa in aanu tixgelin isku-xidhka aasaasiga ah, laakiin sidoo kale isku-xidhka sare ee isku-dhafan ee ay sameeyeen bonds hydrogen ee u dhexeeya molecules. Isku-xidhka aasaasiga ah ee poliurethane waa ka duwan yahay qaabka vulcanization ee caag hydroxyl. Its amino ester group, kooxda biuret, kooxda urea formate iyo kooxaha kale ee functional waxaa loo habeeyey in si joogto ah iyo kala fogaan ah qayb silsilad adag, taasoo keentay in qaab-dhismeedka shabakad joogto ah caag, kaas oo uu leeyahay caabbinta xirashada heer sare ah iyo sifooyin kale oo aad u fiican. Marka labaad, iyada oo ay ugu wacan tahay joogitaanka kooxo badan oo shaqeynaya oo isku xiran sida HOL ama kooxaha karbamate ee caagga polyurethane, bond bonds ee ka dhex abuurmay silsiladaha kelli waxay leeyihiin xoog sare, iyo xidhmooyinka isdhaafsiga sare ee ay sameeyeen bonds hydrogen ayaa sidoo kale saameyn weyn ku leh sifooyinka caag poliurethane. Isku-xidhka sare ee isku-tallaabta ayaa awood u siinaya caag poliurethane inuu lahaado sifadaha elastomers-ka heerkulbeegga hal dhinac, dhinaca kalena, isku-xidhka-isku-tallaabta dhab ahaantii maaha mid isku-xiran, taasoo ka dhigaysa isku-tallaabta farsamada ah. Xaaladda isku-xiran waxay ku xiran tahay heerkulka. Marka heerkulku kordho, isku-xidhanaanshahan ayaa si tartiib tartiib ah u daciifa oo baaba'a. polymerku wuxuu leeyahay dareere gaar ah waxaana lagu sakhri karaa habayn heerkulbeeg ah. Marka heerkulku hoos u dhaco, isku-xidhanaanshahan ayaa si tartiib tartiib ah u soo kabsanaya oo mar kale sameysma. Ku darida qadar yar oo buuxin ah waxay kordhisaa masaafada u dhaxaysa molecules, waxay daciifisaa awoodda samaynta bonds hydrogen ee u dhexeeya molecules, waxayna keentaa hoos u dhac xoog leh. Cilmi-baaristu waxay muujisay in nidaamka xasilloonida ee kooxaha kala duwan ee shaqeynaya ee ku jira caagga poliurethane ee sare ilaa hoose waa: ester, ether, urea, carbamate, iyo biuret. Inta lagu jiro habka gabowga ee caagga polyurethane, tallaabada ugu horreysa waa jebinta isku-xidhka isku-xidhka ah ee u dhexeeya biuret iyo HOL, oo ay ku xigto jebinta carbamate iyo urea bonds, taas oo ah, jebinta silsiladda ugu weyn.
01 Jilicsan
Elastomers Polyurethane, sida maadooyin badan oo polymer ah, waxay ku jilciyaan heerkul sare waxayna ka gudbaan xaalad laastikada una gudubta qulqulka viscous, taasoo keentay hoos u dhac degdeg ah oo xoogga farsamada ah. Marka loo eego dhinaca kiimikaad, heerkulka jilicsanaanta ee barti wuxuu inta badan ku xiran yahay arrimo ay ka mid yihiin ka kooban yahay kiimiko, miisaanka unugyada qaraabada ah, iyo cufnaanta isdhaafsiga.
Guud ahaan, kordhinta miisaanka molecular ee qaraabada ah, kordhinta qallafsanaanta qaybta adag (sida soo bandhigida giraanta benzene ee molecule) iyo waxa ku jira qaybta adag, iyo kordhinta cufnaanta isgoysyada ayaa dhammaantood faa'iido u leh kordhinta heerkulka jilicsan. Dabaqadaha heerkulbeegga, qaab-dhismeedka molecular inta badan waa toosan, iyo heerkulka jilicsan ee elastomerku sidoo kale wuu kordhiyaa marka miisaanka unugyadu kordho.
Xeeladaha polyurethane-ka ee isku-tallaabta ah, cufnaanta isku-xiran waxay leedahay saameyn ka weyn culeyska unugyada unugyada. Sidaa darteed, marka la soo saaro elastomers, kordhinta shaqeynta isocyanates ama polyols waxay samayn karaan qaab-dhismeedka isku-xidhka isku-xidhka kiimikada kuleyl ahaan deggan ee qaar ka mid ah molecules-ka laastikada, ama iyadoo la adeegsanayo saamiga isocyanate xad-dhaaf ah si loo sameeyo qaab-dhismeedka isocyanate xasilloon hab xoog leh oo lagu hagaajinayo caabbinta kulaylka, caabbinta dareeraha, iyo xoogga farsamada ee elastomerka.
Marka PPDI (p-phenyldiisocyanate) loo isticmaalo sida alaabta ceeriin, sababtoo ah isku xirka tooska ah ee laba kooxood oo isocyanate ah oo ku xiran giraanta benzene, qaybta adag ee la sameeyay ayaa leh qayb sare oo benzene ah, taas oo hagaajinaysa qallafsanaanta qaybta adag oo sidaas awgeed kor u qaadaysa. caabbinta kulaylka ee elastomer.
Marka laga eego dhinaca jirka, heerkulka jilicsan ee elastomers wuxuu ku xiran yahay heerka kala soocida microphase. Sida laga soo xigtay warbixinnada, heerkulka jilcin ee elastomers ee aan marin kala-soocida microphase-ka ayaa aad u hooseeya, iyadoo heerkulku yahay 70 ℃ oo keliya, halka elastomers ee sooca microphase-ka ay gaari karaan 130-150 ℃. Sidaa darteed, kordhinta heerka kala soocida microphase ee elastomers waa mid ka mid ah hababka wax ku oolka ah ee lagu hagaajinayo caabbinta kulaylkooda.
Heerka kala-soocida microphase ee elastomers waa lagu wanaajin karaa iyadoo la beddelo qaybinta miisaanka kelli ee qaraabada ah ee qaybaha silsiladaha iyo waxa ku jira qaybaha silsiladaha adag, si kor loogu qaado caabbinta kulaylkooda. Cilmi-baarayaasha intooda badani waxay aaminsan yihiin in sababta kala-soocida microphase-ka ee polyurethane ay tahay is-waafajinta heerkulbeegga ee u dhexeeya qaybaha jilicsan iyo kuwa adag. Nooca silsiladaha fidiyaha, qaybta adag iyo waxa ku jira, nooca qaybta jilicsan, iyo isku xidhka hydrogen dhamaantood waxay ku leeyihiin saameyn weyn.
Marka la barbar dhigo fidiyeyaasha silsiladaha diol, fidiyeyaasha silsiladaha diamine sida MOCA (3,3-dichloro-4,4-diaminodiphenylmethane) iyo DCB (3,3-dichloro-biphenylenediamine) waxay sameeyaan kooxo badan oo amino ester ah oo elastomers ah, iyo curaarta hydrogen ka badan ayaa sameyn kara la sameeyo inta u dhaxaysa qaybo adag, kordhinta isdhexgalka ka dhexeeya qaybaha adag iyo hagaajinta heerka kala-soocidda microphase ee elastomers; Fidiyeyaasha silsiladaha udgoonka ah sida p, p-dihydroquinone, iyo hydroquinone waxay faa'iido u leeyihiin caadiyeynta iyo xirmooyinka adag ee qaybaha adag, taas oo hagaajinaysa kala-soocidda microphase ee alaabta.
Qaybaha amino ester-ka ee ay sameeyeen isocyanates aliphatic waxay leeyihiin iswaafajin wanaagsan oo leh qaybaha jilicsan, taasoo keentay in qaybo badan oo adag ay ku milmaan qaybaha jilicsan, yaraynta heerka kala-soocida microphase. Qaybaha amino ester-ka ee ay sameeyeen isocyanates caraf udgoon ayaa ku habboonayn liidata qaybaha jilicsan, halka heerka kala-soocidda microphase-ka uu sarreeyo. Polyolefin polyurethane wuxuu leeyahay qaab-dhismeedka kala-soocida microphase ku dhawaad dhammaystiran sababtoo ah xaqiiqda ah in qaybta jilicsan aysan samaynin curaarta hydrogen iyo bonds hydrogen waxay ku dhici kartaa oo kaliya qaybta adag.
Saamaynta isku xidhka hydrogen ee barta jilicsan ee elastomers ayaa sidoo kale ah mid muhiim ah. Inkasta oo polyeter-yada iyo carbonyls ee qaybta jilicsan ay samayn karaan tiro badan oo bonds hydrogen ah oo leh NH ee qaybta adag, waxay sidoo kale kordhisaa heerkulka jilicsan ee elastomers. Waxaa la xaqiijiyay in curaarta hydrogen ay wali sii hayso 40% at 200 ℃.
02 Kulul dumis
Kooxaha Amino ester waxay maraan hoos u dhaca soo socda heerkulka sare:
- RNHCOOR - RNC0 HO-R
- RNHCOOR - RNH2 CO2 ene
- RNHCOOR - RNHR CO2 ene
Waxaa jira saddex nooc oo waaweyn oo kala-goynta kulaylka ah ee alaabta ku salaysan polyurethane:
① Samaynta isocyyanates asalka ah iyo polyols;
② α- Xidhiidhka ogsijiinta ee saldhigga CH2 wuu jabaa oo wuxuu ku daraa hal bond hydrogen oo ku yaal CH2 labaad si ay u sameeyaan amino acids iyo alkenes. Amino acids waxay u kala baxaan hal amine aasaasiga ah iyo carbon dioxide:
③ Foomka 1 aminiga sare iyo kaarboon dioxide.
Burburka kulaylka ee qaab dhismeedka carbamate:
Aryl NHCO Aryl, ~ 120 ℃;
N-alkyl-NHCO-aryl, ~ 180 ℃;
Aryl NHCO n-alkyl, ~ 200 ℃;
N-alkyl-NHCO-n-alkyl,~250 ℃.
Xasiloonida kulaylka ee esters amino acid waxay la xiriirtaa noocyada alaabta bilawga ah sida isocyanates iyo polyols. Aliphatic isocyanates way ka sarreeyaan isocyanates caraf udgoon, halka alkolada dufanku ay ka sarreeyaan aalkolada udgoonka ah. Si kastaba ha ahaatee, suugaanta ayaa sheegaysa in kulaylka burburka ee esters aliphatic amino acid uu u dhexeeyo 160-180 ℃, iyo kan esters amino acid udgoon waa inta u dhaxaysa 180-200 ℃, taas oo aan waafaqsanayn xogta kor ku xusan. Sababta ayaa laga yaabaa inay la xiriirto habka tijaabada.
Dhab ahaantii, aliphatic CHDI (1,4-cyclohexane diisocyanate) iyo HDI (hexamethylene diisocyanate) waxay leeyihiin iska caabin kulayl ka wanaagsan marka loo eego sida caadiga ah loo isticmaalo udgoonka MDI iyo TDI. Gaar ahaan trans CHDI oo leh qaab-dhismeed summeedka ayaa loo aqoonsaday inuu yahay isocyanate-ka ugu adkaysiga badan. Elastomers Polyurethane ee laga diyaariyey waxay leeyihiin hab-socodka wanaagsan, iska caabbinta hydrolysis heer sare ah, heerkul jilicsan oo sarreeya, heerkulka kala-guurka dhalada oo hooseeya, kuleylka kuleylka hooseeya, iyo caabbinta UV sare.
Marka laga soo tago kooxda amino ester-ka, polyurethane elastomers waxa kale oo ay leeyihiin kooxo kale oo shaqaynaya sida urea formate, biuret, HOL, iwm.
NHCONCOO - (aliphatic urea formate), 85-105 ℃;
- NHCONCOO - (qaabka urea caraf udgoon), oo heerkulkeedu yahay 1-120 ℃;
- NHCONCONH - (aliphatic biuret), heerkul u dhexeeya 10 ° C ilaa 110 ° C;
NHCONCONH - (biuret caraf udgoon), 115-125 ℃;
NHCONH - (urea aliphatic), 140-180 ℃;
- NHCONH - (urea udgoon), 160-200 ℃;
Isocyanurate giraanta>270 ℃.
Heerkulka kala-goynta kulaylka ee qaabka biuret iyo urea ku salaysan ayaa aad uga hooseeya kan aminoformate iyo urea, halka isocyanurate uu leeyahay xasilloonida kulaylka ugu fiican. Soo saarista elastomers, isocyanates-ka xad-dhaafka ah ayaa sii falcelin kara aminoformate-ka la sameeyay iyo urea si ay u sameeyaan qaab-dhismeedka urea iyo qaab-dhismeedka isku-xiran ee biuret. Inkasta oo ay hagaajin karaan sifooyinka farsamada ee elastomers, aad bay u deggan yihiin kuleylka.
Si loo yareeyo kulaylka aan degganayn kooxaha sida biuret iyo urea formate ee elastomers, waxaa lagama maarmaan ah in la tixgeliyo saamiga alaabta ceeriin iyo habka wax soo saarka. Saamiyada isocyanate ee xad-dhaafka ah waa in la adeegsadaa, habab kale waa in la isticmaalaa inta ugu badan ee suurtogalka ah si marka hore loo sameeyo qayb ka mid ah giraangiraha isocyyanate ee alaabta ceeriin (inta badan isocyyanates, polyols, iyo silsiladaha silsiladaha), ka dibna u baro elastomer sida waafaqsan hababka caadiga ah. Tani waxay noqotay habka ugu badan ee loo isticmaalo soo saarida elastomeryada polyurethane kulaylka u adkaysta iyo ololka.
03 Hydrolysis iyo oksaydhka kulaylka
Elastomers-ka polyurethane waxay u nugul yihiin kala-goynta kulaylka ee qaybahooda adag iyo isbeddelada kiimikaad ee u dhigma ee qaybaha jilicsan ee heerkul sare. Elastomers-ka Polyester-ka ayaa leh iska caabbinta biyaha oo liidata iyo u janjeera aad u daran inay biyo ku shubaan heerkul sare. Nolosha adeegga polyester/TDI/diamine waxay gaari kartaa 4-5 bilood at 50 ℃, kaliya laba toddobaad oo ah 70 ℃, iyo dhawr maalmood oo keliya ka sarreeya 100 ℃. Xirmooyinka Ester-ku waxay u kala jajabi karaan asiidhyo iyo aalkolo u dhigma marka ay la kulmaan biyaha kulul iyo uumiga, iyo urea iyo kooxaha ester-ka amino ee elastomers waxay sidoo kale mari karaan falcelinta hydrolysis:
RCOOR H20- → RCOOH HOR
khamriga Ester
Hal RNHCONHR hal H20- → RXHCOOH H2NR -
Ureamide
Hal RNHCOOR-H20- → RNCOOH HOR -
Amino formate ester Amino formate khamriga
Elastomers-ku-salaysan polyeter-ku waxay leeyihiin xasillooni oksaydh kuleyl ah oo liidata, iyo ether-ku-salaysan elastomers α- Haydaroojiinka ku jira atamka kaarboonka ayaa si fudud oksaydhaysan loo sameeyaa, isagoo samaynaya hydrogen peroxide. Ka dib burburka iyo kala-goynta dheeraadka ah, waxay abuurtaa xaglaha oxide iyo radicals hydroxyl, kuwaas oo ugu dambeyntii u jajaban qaababka ama aldehydes.
Polyester-yada kala duwan ayaa saameyn yar ku leh caabbinta kulaylka ee elastomers, halka polyeterrada kala duwan ay leeyihiin saameyn gaar ah. Marka la barbar dhigo TDI-MOCA-PTMEG, TDI-MOCA-PTMEG waxay leedahay xadiga xajinta xoogga xajinta ee 44% iyo 60% siday u kala horreeyaan markay da'doodu tahay 121 ℃ muddo 7 maalmood ah, iyadoo kan dambe uu aad uga wanaagsan yahay kii hore. Sababtu waxay noqon kartaa in molecules PPG ay leeyihiin silsilado laamo ah, kuwaas oo aan ku habboonayn habaynta joogtada ah ee molecules laastikada waxayna yareeyaan caabbinta kulaylka ee jirka jilicsan. Nidaamka xasiloonida kulaylka ee polyeter-ka waa: PTMEG>PEG>PPG.
Kooxaha kale ee shaqeeya ee elastomers-ka polyurethane, sida urea iyo karbamate, waxay sidoo kale maraan falcelinta oksaydhka iyo hydrolysis. Si kastaba ha ahaatee, kooxda ether-ka ayaa ah kuwa ugu fudud ee oksaydhisku, halka kooxda ester-ka ay tahay kuwa ugu sahlan ee la nadiifiyo. Nidaamka iska caabbinta antioxidant-ka iyo hydrolysis waa:
Dhaqdhaqaaqa Antioxidant: esters>urea>carbamate>ether;
Iska caabbinta Hydrolysis: ester
Si loo hagaajiyo iska caabinta oksaydhka ee polyether polyurethane iyo iska caabbinta hydrolysis ee polyester polyurethane, waxyaabaha lagu daro ayaa sidoo kale lagu daraa, sida ku darista 1% phenolic antioxidant Irganox1010 ilaa PTMEG polyether elastomer. Awooda xajinta ee elastomerkan waxa lagu kordhin karaa 3-5 jeer marka loo eego antioksidanter la'aan (natiijooyinka tijaabada ka dib gabow 1500C 168 saacadood). Laakiin ma aha antioxidant kasta oo saameyn ku leh elastomers polyurethane, kaliya phenolic 1rganox 1010 iyo TopanOl051 (antioxidant phenolic, xasilinta amine light stabilizer, complex benzotriazole) waxay leeyihiin saameyno muhiim ah, kii horena waa kan ugu fiican, suurtogalnimada sababtoo ah antioxidants phenolic waxay leeyihiin iswaafajin wanaagsan oo leh elastomers. Si kastaba ha ahaatee, sababtoo ah doorka muhiimka ah ee kooxaha phenolic hydroxyl ee habka xasilinta ee antioxidants phenolic, si looga fogaado fal-celinta iyo "guuldarrida" kooxdan phenolic hydroxyl ee kooxaha isocyanate ee nidaamka, saamiga isocyanates iyo polyols waa inaysan noqon aad u weyn, iyo antioxidants waa in lagu daraa prepolymers iyo silsilad fidiyeyaasha. Haddii lagu daro inta lagu jiro wax soo saarka prepolymers, waxay si weyn u saameyn doontaa saameynta xasilinta.
Waxyaabaha lagu daro ee loo isticmaalo si looga hortago hydrolysis of polyester polyurethane elastomers ayaa inta badan ah xeryahooda carbodiimide, kuwaas oo ka falceliya asiidhyada karboxilic ee ay soo saarto ester hydrolysis ee molecules elastomer polyurethane si ay u abuurto derivatives urea acyl, ka hortagga hydrolysis dheeraad ah. Ku darida karbodiimide ee qayb ka mid ah 2% ilaa 5% waxay kordhin kartaa xasilloonida biyaha ee polyurethane 2-4 jeer. Intaa waxaa dheer, tert butyl catechol, hexamethylenetetramine, azodicarbonamide, iwm sidoo kale waxay leeyihiin saameyn liddi ku ah hydrolysis qaarkood.
04 Tilmaamaha waxqabadka ugu muhiimsan
Elastomers-ka Polyurethane waa copolymers-ka kala-duwan ee caadiga ah, oo leh silsilado molecular oo ka kooban qaybo dabacsan oo leh heerkulka kala-guurka galaas oo ka hooseeya heerkulka qolka iyo qaybo adag oo leh heerkulka kala-guurka galaas oo ka sarreeya heerkulka qolka. Waxaa ka mid ah, polyols oligomeric waxay sameeyaan qaybo dabacsan, halka diisocyanates iyo silsiladaha silsiladaha molecule yar ay sameeyaan qaybo adag. Qaab dhismeedka isku xidhan ee qaybaha silsiladaha dabacsan iyo kuwa adag ayaa go'aamiya waxqabadkooda gaarka ah:
(1) Kala duwanaanta engegnaanta caagga caadiga ah waxay guud ahaan u dhaxaysaa Shaoer A20-A90, halka kala duwanaanta caaggu ay ku saabsan tahay Shaoer A95 Shaoer D100. Elastomers Polyurethane waxay gaari karaan sida ugu hooseeya Shaoer A10 iyo sida ugu sarreeya Shaoer D85, iyada oo aan loo baahnayn gargaar buuxin;
(2) Xoog sare iyo barti weli waa lagu hayn karaa gudaha tiro balaadhan oo adag;
(3) caabbinta xirashada heer sare ah, 2-10 jeer ka caagga dabiiciga ah;
(4) Biyo, saliid, iyo kiimikooyin iska caabin heer sare ah;
(5) Iska caabbinta saameynta sare, caabbinta daalka, iyo caabbinta gariirka, oo ku habboon codsiyada foorarsiga sare ee soo noqnoqda;
(6) Iska caabin heerkul hooseeya oo wanaagsan, oo leh heerkul hoose oo jajaban oo ka hooseeya -30 ℃ ama -70 ℃;
(7) Waxay leedahay wax-qabad heersare ah oo heer sare ah, sababtoo ah heerkulka hooseeya ee kuleylka, waxay leedahay saameyn wanaagsan marka loo eego caag iyo caag;
(8) Biyo laqabsi wanaagsan iyo sifooyinka xinjirowga lidka ku ah;
(9) Dahaar koronto oo heer sare ah, caabbinta caaryada, iyo xasilloonida UV.
Elastomers Polyurethane waxaa lagu samayn karaa iyada oo la isticmaalayo habab la mid ah sida caagga caadiga ah, sida balaastiigga, isku dhafka, iyo vulcanization. Waxa kale oo lagu qaabayn karaa qaab caag dareere ah iyadoo la shubayo, qaabaynta centrifugal, ama buufinta. Waxa kale oo laga samayn karaa walxo granular ah waxaana la samayn karaa iyadoo la isticmaalayo duritaan, extrusion, rogid, dharbaaxo, iyo habab kale. Sidan oo kale, ma aha oo kaliya inay hagaajiso hufnaanta shaqada, laakiin sidoo kale waxay hagaajinaysaa saxnaanta cabbirka iyo muuqaalka alaabta.
Waqtiga boostada: Dec-05-2023