Okuthiwai-polyurethaneisifinyezo se-polyurethane, esakhiwe ukusabela kwe-polyisocyanates nama-polyols, futhi iqukethe amaqembu amaningi aphindaphindiwe e-amino ester (- NH-CO-O -) ochungechungeni lwamangqamuzana. Kuma-resin enziwe nge-polyurethane angempela, ngaphezu kweqembu le-amino ester, kukhona namaqembu afana ne-urea ne-biuret. Ama-Polyols ayingxenye yama-molecule amaketanga amade anamaqembu e-hydroxyl ekugcineni, abizwa ngokuthi "ama-soft chain segments", kuyilapho ama-polyisocyanate abizwa ngokuthi "izingxenye zamaketanga aqinile".
Phakathi kwama-polyurethane resins akhiqizwa izingxenye zamaketanga athambile futhi aqinile, amaphesenti amancane kuphela ama-amino acid esters, ngakho-ke kungase kungafaneleki ukuwabiza ngokuthi i-polyurethane. Ngomqondo obanzi, i-polyurethane iyisengezo se-isocyanate.
Izinhlobo ezahlukene ze-isocyanate zisabela ngezinhlanganisela ze-polyhydroxy ukuze zikhiqize izakhiwo ezihlukahlukene ze-polyurethane, ngaleyo ndlela zithole izinto ze-polymer ezinezakhiwo ezahlukene, njengepulasitiki, irabha, izintambo, imicu, izinto zokunamathisela, njll. Irabha ye-polyurethane
Irabha ye-polyurethane ingeyohlobo olukhethekile lwenjoloba, olwenziwa ngokuphendula i-polyether noma i-polyester nge-isocyanate. Kunezinhlobonhlobo eziningi ngenxa yezinhlobo ezahlukene zezinto zokusetshenziswa, izimo zokusabela, nezindlela zokuxhumanisa. Ngokombono wesakhiwo samakhemikhali, kunezinhlobo ze-polyester ne-polyether, futhi ngokombono wendlela yokucubungula, kunezinhlobo ezintathu: uhlobo lokuxuba, uhlobo lokuphonsa, nohlobo lwe-thermoplastic.
Irabha yokwenziwa ye-polyurethane ngokuvamile ihlanganiswa ngokusabela i-polyester ewumugqa noma i-polyether ene-disocyanate ukuze yakhe i-prepolymer yesisindo se-molecular ephansi, ebese ingaphansi kokusabela kokunwetshwa kweketango ukuze kukhiqizwe i-polymer yesisindo samangqamuzana aphezulu. Khona-ke, ama-crosslinking agents afanelekile ayengezwa futhi ashiselwe ukuze alaphe, abe yinjoloba engcolile. Le ndlela ibizwa ngokuthi i-prepolymerization noma indlela yezinyathelo ezimbili.
Kungenzeka futhi ukusebenzisa indlela yesinyathelo esisodwa - ukuxuba ngokuqondile i-polyester eqondile noma i-polyether nama-disocyanates, ama-chain extender, nama-crosslinking agents ukuze uqalise ukusabela futhi ukhiqize irabha ye-polyurethane.
I-A-segment kuma-molecule e-TPU yenza amaketanga e-macromolecular ajikeleze kalula, inikeze irabha ye-polyurethane ukunwebeka okuhle, inciphisa indawo yokuthambisa kanye nephuzu loshintsho lwesibili lwe-polymer, futhi yehlise ubulukhuni bayo namandla emishini. I-B-segment izobopha ukujikeleza kwamaketanga e-macromolecular, okubangela ukuthi iphuzu lokuthambisa kanye nephuzu lokuguqulwa kwesibili le-polymer likhuphuke, okuholela ekwandeni kokuqina namandla emishini, nokuncipha kokunwebeka. Ngokulungisa isilinganiso se-molar phakathi kuka-A no-B, ama-TPU anezici ezihlukahlukene zemishini angakhiqizwa. Isakhiwo sokuxhumanisa esiphambanweni se-TPU akumele sicabangele ukuxhumanisa okuyisisekelo kuphela, kodwa futhi nokuxhumanisa okwesibili okwakhiwa ngamabhondi e-hydrogen phakathi kwama-molecule. Isibopho esiyinhloko sokuxhumanisa i-polyurethane sihlukile esakhiweni se-vulcanization serabha ye-hydroxyl. Iqembu layo le-amino ester, iqembu le-biuret, iqembu le-urea formate namanye amaqembu asebenzayo ahlelwe engxenyeni yeketanga eliqinile elivamile futhi elinezikhala, okuholela ekwakhekeni kwenethiwekhi evamile yenjoloba, enokumelana okuhle kakhulu kokugqoka nezinye izinto ezinhle kakhulu. Okwesibili, ngenxa yokuba khona kwamaqembu amaningi asebenza ngokubambisana kakhulu afana namaqembu e-urea noma e-carbamate enjolobeni ye-polyurethane, izibopho ze-hydrogen ezakhiwe phakathi kwamaketanga amangqamuzana zinamandla amakhulu, kanti izibopho zesibili zokuphambana ezakhiwe ngamabhondi e-hydrogen nazo zinomthelela omkhulu ezimpahleni ze-hydrogen. irabha ye-polyurethane. Ukuxhumanisa okwesibili kuvumela irabha ye-polyurethane ukuthi ibe nezici zama-thermosetting elastomers ngakolunye uhlangothi, futhi ngakolunye uhlangothi, lokhu kuxhumanisa akuxhumene ngempela, okwenza kube ukuxhumanisa okubonakalayo. Isimo sokuxhumanisa sincike ekushiseni. Njengoba izinga lokushisa likhuphuka, lokhu kuxhumanisa kancane kancane kuba buthaka futhi kuyanyamalala. I-polymer ine-fluidity ethile futhi ingafakwa ngaphansi kokucubungula kwe-thermoplastic. Lapho izinga lokushisa lehla, lokhu kuxhumanisa kuyalulama kancane kancane futhi kwakheke futhi. Ukwengezwa kwenani elincane lokugcwalisa kwandisa ibanga phakathi kwama-molecule, kwenza buthaka ikhono lokwakha izibopho ze-hydrogen phakathi kwama-molecule, futhi kuholela ekwehleni okubukhali kwamandla. Ucwaningo luye lwabonisa ukuthi ukuhleleka kokuzinza kwamaqembu ahlukahlukene asebenzayo ku-polyurethane rubber kusuka phezulu kuya phansi: i-ester, i-ether, i-urea, i-carbamate, ne-biuret. Phakathi nenqubo yokuguga yenjoloba ye-polyurethane, isinyathelo sokuqala ukugqashuka kwezibopho ezixhumanisa phakathi kwe-biuret ne-urea, okulandelwa ukugqashuka kwe-carbamate ne-urea bond, okungukuthi, ukugqashuka kweketanga eliyinhloko.
01 Ukuthambisa
Ama-polyurethane elastomers, njengezinto eziningi ze-polymer, athambeka emazingeni okushisa aphezulu futhi aguquke asuke esimweni sokunwebeka aye esimweni sokugeleza kwe-viscous, okuholela ekwehleni okusheshayo kwamandla emishini. Ngokombono wamakhemikhali, izinga lokushisa elithambile lokunwebeka lincike ikakhulukazi ezintweni ezifana nokwakheka kwamakhemikhali, isisindo samangqamuzana ahlobene, kanye nokuminyana okuhlanganayo.
Ngokuvamile, ukukhulisa isisindo samangqamuzana ahlobene, ukukhulisa ukuqina kwengxenye eqinile (njengokwethula iringi ye-benzene ku-molecule) nokuqukethwe kwengxenye eqinile, nokukhulisa ukuminyana kokuxhumanisa konke kuyinzuzo ekwandiseni izinga lokushisa elithambile. Kuma-thermoplastic elastomers, ukwakheka kwamangqamuzana ikakhulukazi kumugqa, futhi izinga lokushisa elithambile le-elastomer nalo liyakhuphuka lapho isisindo samangqamuzana esihlobene sikhuphuka.
Kuma-elastomer e-polyurethane axhumene, ukuminyana okuxhumanisayo kunomthelela omkhulu kunesisindo samangqamuzana ahlobene. Ngakho-ke, lapho kukhiqizwa ama-elastomers, ukwandisa ukusebenza kwama-isocyanate noma ama-polyols kungakha isakhiwo senethiwekhi esizinzile esixhumanisa amakhemikhali kwamanye ama-molecule anwebekayo, noma kusetshenziswa izilinganiso ze-isocyanate ezeqile ukuze kwakhiwe isakhiwo sokuxhumanisa esizinzile se-isocyanate emzimbeni onwebekayo. indlela enamandla yokuthuthukisa ukumelana nokushisa, ukumelana ne-solvent, namandla omshini we-elastomer.
Uma i-PPDI (p-phenyldiisocyanate) isetshenziswa njengento eluhlaza, ngenxa yokuxhumana okuqondile kwamaqembu amabili e-isocyanate kwendandatho ye-benzene, ingxenye eqinile eyakhiwe inokuqukethwe kwendandatho ye-benzene ephakeme, ethuthukisa ukuqina kwengxenye eqinile futhi ngaleyo ndlela ithuthukise. ukumelana nokushisa kwe-elastomer.
Ngokombono wenyama, izinga lokushisa elithambile lama-elastomers lincike ezingeni lokuhlukaniswa kwe-microphase. Ngokusho kwemibiko, izinga lokushisa elithambile lama-elastomer angadluli ukuhlukaniswa kwe-microphase liphansi kakhulu, ngokushisa kokucubungula okungaba ngu-70 ℃ kuphela, kuyilapho ama-elastomers adlula ngokuhlukana kwe-microphase angafinyelela ku-130-150 ℃. Ngakho-ke, ukwandisa izinga lokuhlukaniswa kwe-microphase kuma-elastomers kungenye yezindlela eziphumelelayo zokuthuthukisa ukumelana nokushisa kwazo.
Izinga lokuhlukaniswa kwe-microphase lama-elastomers lingathuthukiswa ngokushintsha ukusatshalaliswa kwesisindo samangqamuzana okuhlobene kwamasegimenti amaketango kanye nokuqukethwe kwamasegimenti amaketango aqinile, ngaleyo ndlela kuthuthukiswe ukumelana kwawo nokushisa. Abacwaningi abaningi bakholelwa ukuthi isizathu sokuhlukaniswa kwe-microphase ku-polyurethane ukungahambisani kwe-thermodynamic phakathi kwezingxenye ezithambile neziqinile. Uhlobo lwe-chain extender, ingxenye eqinile nokuqukethwe kwayo, uhlobo lwengxenye ethambile, kanye ne-hydrogen bonding konke kunomthelela omkhulu kukho.
Uma kuqhathaniswa nezandisi ze-diol chain, izandisi ze-diamine chain ezifana ne-MOCA (3,3-dichloro-4,4-diaminodiphenylmethane) kanye ne-DCB (3,3-dichloro-biphenylenediamine) zakha amaqembu amaningi e-polar amino ester kuma-elastomer, kanye namabhondi e-hydrogen amaningi kwakhiwe phakathi kwezingxenye eziqinile, okwandisa ukusebenzisana phakathi kwezingxenye ezinzima futhi kuthuthukiswe izinga lokuhlukaniswa kwe-microphase ku ama-elastomers; Izandiso zamaketango ephunga elimnandi ezifana ne-p, i-p-dihydroquinone, ne-hydroquinone zizuzisa ekwenzeni kube okujwayelekile kanye nokupakishwa okuqinile kwamasegimenti aqinile, ngaleyo ndlela kuthuthukise ukuhlukaniswa kwe-microphase yemikhiqizo.
Izingxenye ze-amino ester ezakhiwe ama-aliphatic isocyanate zinokuhambisana okuhle nezingxenye ezithambile, okuholela ekuhlakazweni kwezingxenye eziqinile ezingxenyeni ezithambile, kunciphisa izinga lokuhlukaniswa kwe-microphase. Amasegimenti e-amino ester akhiwe ama-isocyanate anephunga elimnandi awahambisani kahle namasegimenti athambile, kuyilapho izinga lokuhlukaniswa kwe-microphase liphezulu. I-Polyolefin polyurethane inesakhiwo sokuhlukanisa se-microphase esicishe siphelele ngenxa yokuthi ingxenye ethambile ayiwakhi amabhondi e-hydrogen futhi amabhondi e-hydrogen angenzeka kuphela engxenyeni eqinile.
Umthelela we-hydrogen bonding endaweni ethambisayo yama-elastomers nawo ubalulekile. Nakuba ama-polyethers nama-carbonyls engxenyeni ethambile angakha inani elikhulu lamabhondi e-hydrogen ne-NH engxenyeni eqinile, futhi kwandisa izinga lokushisa elithambile lama-elastomers. Kuqinisekisiwe ukuthi amabhondi e-hydrogen asagcina ama-40% ku-200 ℃.
02 Ukubola okushisayo
Amaqembu e-amino ester abola ngokulandelayo emazingeni okushisa aphezulu:
- RNHCOOR – RNC0 HO-R
- RNHCOOR – RNH2 CO2 ene
- RNHCOOR – RNHR CO2 ene
Kunezinhlobo ezintathu eziyinhloko zokubola okushisayo kwezinto ezisekelwe ku-polyurethane:
① Ukwakha ama-isocyanate angempela nama-polyols;
② α— Ibhondi ye-oxygen kusisekelo se-CH2 iyaphuka futhi ihlanganiswe nebhondi ye-hydrogen eyodwa kweyesibili i-CH2 yakhe ama-amino acid nama-alkene. Ama-amino acid abola abe yi-amine eyodwa eyinhloko ne-carbon dioxide:
③ Ifomu 1 i-amine yesibili ne-carbon dioxide.
Ukubola okushisayo kwesakhiwo se-carbamate:
I-Aryl NHCO Aryl, ~ 120 ℃;
I-N-alkyl-NHCO-aryl,~180 ℃;
I-Aryl NHCO n-alkyl,~200 ℃;
N-alkyl-NHCO-n-alkyl,~250 ℃.
Ukuzinza okushisayo kwama-amino acid esters kuhlobene nezinhlobo zezinto zokuqala ezifana ne-isocyanates nama-polyols. Ama-aliphatic isocyanate aphezulu kunama-isocyanate anuka kamnandi, kuyilapho ama-alcohol anamafutha aphezulu kunotshwala obunuka kamnandi. Kodwa-ke, izincwadi zibika ukuthi izinga lokushisa elishisayo lokubola kwe-aliphatic amino acid esters liphakathi kuka-160-180 ℃, kanye nama-amino acid ester anephunga elimnandi liphakathi kuka-180-200 ℃, okungahambisani nedatha engenhla. Isizathu singase sihlobane nendlela yokuhlola.
Eqinisweni, i-aliphatic CHDI (1,4-cyclohexane diisocyanate) kanye ne-HDI (hexamethylene diisocyanate) zinokumelana nokushisa okungcono kune-MDI enuka kamnandi esetshenziswa kakhulu ne-TDI. Ikakhulukazi i-trans CHDI enesakhiwo esilinganayo iye yaqashelwa njenge-isocyanate ekwazi ukumelana nokushisa kakhulu. Ama-elastomer e-polyurethane alungiselelwe ukusuka kuwo anokucutshungulwa okuhle, ukumelana okuhle kakhulu kwe-hydrolysis, izinga lokushisa eliphakeme lokuthambisa, izinga lokushisa eliphansi lokushintsha kwengilazi, i-hysteresis eshisayo ephansi, nokumelana okuphezulu kwe-UV.
Ngaphezu kweqembu le-amino ester, ama-polyurethane elastomers aphinde abe namanye amaqembu asebenzayo njenge-urea formate, i-biuret, i-urea, njll. Lawa maqembu angakwazi ukubola ngokushisa okuphezulu:
I-NHCONCOO - (i-aliphatic urea formate), i-85-105 ℃;
I-NHCONCOO - (i-urea enephunga elimnandi), ebangeni lokushisa elingu-1-120 ℃;
- NHCONCONH - (aliphatic biuret), ezingeni lokushisa elisukela ku-10 ° C kuya ku-110 ° C;
I-NHCONCONH – (i-aromatic biuret), 115-125 ℃;
NHCONH – (aliphatic urea), 140-180 ℃;
- NHCONH - (i-urea enamakha), 160-200 ℃;
Isocyanurate ring>270 ℃.
Izinga lokushisa elishisayo lokubola kwe-biuret ne-urea esekelwe ku-formate liphansi kakhulu kunalelo le-aminoformate ne-urea, kuyilapho i-isocyanurate inokuzinza okungcono kakhulu kokushisa. Ekukhiqizweni kwama-elastomers, ama-isocyanate eqile angaqhubeka nokusabela nge-aminoformate eyakhiwe kanye ne-urea ukuze kwakheke i-urea based formate kanye ne-biuret exhumene ngokuphambana izakhiwo. Nakuba zingathuthukisa izakhiwo zemishini yama-elastomers, azinzile ngokwedlulele ekushiseni.
Ukunciphisa amaqembu ashisayo angazinzile njenge-biuret ne-urea formate kuma-elastomers, kuyadingeka ukucabangela isilinganiso sawo sempahla eluhlaza kanye nenqubo yokukhiqiza. Kufanele kusetshenziswe izilinganiso ze-isocyanate ezeqile, futhi ezinye izindlela kufanele zisetshenziswe ngangokunokwenzeka ukuze kuqalwe kwakhiwe izindandatho ze-isocyanate eziyingxenye yezinto zokusetshenziswa (ikakhulukazi ama-isocyanate, ama-polyols, namaketanga okunweba), bese bethula ku-elastomer ngokwezinqubo ezivamile. Lena sekuyiyona ndlela esetshenziswa kakhulu ekukhiqizeni ama-elastomers angavimbeli ukushisa futhi amelana nelangabi.
03 I-Hydrolysis kanye ne-oxidation eshisayo
Ama-elastomer e-polyurethane athambekele ekuboleni okushisayo ezingxenyeni zawo eziqinile kanye nokushintsha kwamakhemikhali ahambisanayo ezingxenyeni zawo ezithambile emazingeni okushisa aphezulu. Ama-elastomer e-polyester awakwazi ukumelana namanzi kanye nokuthambekela okunzima kakhulu kwe-hydrolyze emazingeni okushisa aphezulu. Impilo yesevisi ye-polyester/TDI/diamine ingafinyelela ezinyangeni ezi-4-5 ku-50 ℃, amasonto amabili kuphela ku-70 ℃, kanye nezinsuku ezimbalwa nje ezingaphezu kuka-100 ℃. Amabhondi e-Ester angabola abe ama-asidi ahambisanayo notshwala lapho evezwe emanzini ashisayo nesitimu, futhi amaqembu e-urea nama-amino ester kuma-elastomers nawo angabhekana nokusabela kwe-hydrolysis:
RCOOR H20- → RCOOH HOR
Ester utshwala
I-RNHCONHR eyodwa H20- → RXHCOOH H2NR -
I-Ureamide
Okukodwa RNHCOOR-H20- → RNCOOH HOR -
I-amino formate ester I-amino idala utshwala
Ama-elastomer asuselwa ku-polyether anokuqina okuncane kwe-thermal oxidation, kanye nama-elastomer asekelwe ku-ether α- I-hydrogen ku-athomu ye-carbon i-oxidized kalula, yakhe i-hydrogen peroxide. Ngemva kokubola nokuqhekeka okwengeziwe, ikhiqiza ama-radicals e-oxide nama-hydroxyl radicals, agcina ebolile abe amafomethi noma ama-aldehyde.
Ama-polyester ahlukene anomphumela omncane ekumelana nokushisa kwama-elastomers, kuyilapho ama-polyester ahlukene anethonya elithile. Uma kuqhathaniswa ne-TDI-MOCA-PTMEG, i-TDI-MOCA-PTMEG inezinga lokugcinwa kwamandla e-tensile engu-44% no-60% ngokulandelanayo lapho ineminyaka engu-121 ℃ izinsuku ezingu-7, kanti yokugcina ibe ngcono kakhulu kuneyangaphambili. Isizathu singase sibe ukuthi ama-molecule e-PPG anamaketanga anamagatsha, angahambisani nokuhlelwa okuvamile kwama-molecule anwebekayo futhi anciphise ukumelana nokushisa komzimba okunwebeka. I-thermal stability order yama-polyethers yile: PTMEG>PEG>PPG.
Amanye amaqembu asebenzayo kuma-polyurethane elastomers, njenge-urea ne-carbamate, nawo abhekana nokusabela kwe-oxidation kanye ne-hydrolysis. Kodwa-ke, iqembu le-ether yilona elenziwe i-oxidized kalula, kanti iqembu le-ester yilona elenziwa nge-hydrolyzed kalula. Ukuhleleka kokumelana kwabo ne-antioxidant kanye ne-hydrolysis yile:
Umsebenzi we-Antioxidant: esters>urea>carbamate>ether;
Ukumelana ne-Hydrolysis: i-ester
Ukuthuthukisa ukumelana ne-oxidation ye-polyether polyurethane kanye nokumelana ne-hydrolysis ye-polyester polyurethane, izithasiselo nazo zengezwa, njengokwengeza i-1% ye-phenolic antioxidant Irganox1010 ku-PTMEG polyether elastomer. Amandla aqinile ale elastomer anganyuswa izikhathi ezingu-3-5 uma kuqhathaniswa nangaphandle kwama-antioxidants (imiphumela yokuhlola ngemva kokuguga ku-1500C amahora angu-168). Kodwa akuwona wonke ama-antioxidant anomphumela kuma-polyurethane elastomers, i-phenolic 1rganox 1010 kuphela kanye ne-TopanOl051 (i-phenolic antioxidant, i-hindered amine light stabilizer, i-benzotriazole complex) anemiphumela ebalulekile, futhi eyokuqala ihamba phambili, mhlawumbe ngenxa yokuthi i-phenolic antioxidants inokuhambisana okuhle nama-elastomers. Kodwa-ke, ngenxa yendima ebalulekile yamaqembu e-phenolic hydroxyl endleleni yokuzinzisa ye-phenolic antioxidants, ukuze kugwenywe ukusabela kanye "nokwehluleka" kwaleli qembu le-phenolic hydroxyl elinamaqembu e-isocyanate ohlelweni, isilinganiso sama-isocyanate kuya kuma-polyols akufanele inkulu kakhulu, futhi ama-antioxidants kufanele engezwe kuma-prepolymers nama-chain extender. Uma kwengezwe ngesikhathi sokukhiqizwa kwama-prepolymers, kuzothinta kakhulu umphumela wokuzinza.
Izithasiselo ezisetshenziselwa ukuvimbela i-hydrolysis ye-polyester polyurethane elastomers ikakhulukazi izinhlanganisela ze-carbodiimide, ezisabela nge-carboxylic acid ekhiqizwa i-ester hydrolysis kuma-molecule e-polyurethane elastomer ukuze kukhiqizwe okuphuma kokuphuma kwe-acyl urea, kuvimbele ukuqhubekela phambili kwe-hydrolysis. Ukwengezwa kwe-carbodiimide engxenyeni enkulu ka-2% kuya ku-5% kungakhuphula ukuzinza kwamanzi e-polyurethane izikhathi ezingu-2-4. Ngaphezu kwalokho, i-tert butyl catechol, i-hexamethylenetetramine, i-azodicarbonamide, njll. futhi inemiphumela ethile ye-anti hydrolysis.
04 Izici zokusebenza eziyinhloko
Ama-polyurethane elastomers angama-multi block copolymers, anamaketanga e-molecular akhiwe izingxenye eziguquguqukayo ezinezinga lokushisa elishintshashintshayo lengilazi eliphansi kunezinga lokushisa legumbi kanye nezingxenye eziqinile ezinezinga lokushisa lengilazi elingaphezu kwezinga lokushisa legumbi. Phakathi kwazo, ama-oligomeric polyols akha izingxenye eziguquguqukayo, kuyilapho ama-disocyanate nama-molecule amancane ama-extenders enza amasegimenti aqinile. Isakhiwo esishumekiwe samasegimenti eketango aguquguqukayo futhi aqinile sinquma ukusebenza kwawo okuhlukile:
(1) Ububanzi bokuqina benjoloba evamile ngokuvamile buphakathi kwe-Shaoer A20-A90, kuyilapho ububanzi bobulukhuni bepulasitiki bumayelana ne-Shaoer A95 Shaoer D100. Ama-elastomer e-polyurethane angafinyelela aphansi njenge-Shaoer A10 futhi afinyelele phezulu njenge-Shaoer D85, ngaphandle kwesidingo sosizo lokugcwalisa;
(2) Amandla aphezulu kanye nokunwebeka kusengagcinwa phakathi kobunzima obuhlukahlukene;
(3) Ukumelana nokugqoka okuhle kakhulu, izikhathi ezi-2-10 kunerabha yemvelo;
(4) Ukumelana kahle namanzi, uwoyela, namakhemikhali;
(5) Ukumelana nomthelela omkhulu, ukumelana nokukhathala, nokumelana nokudlidliza, kulungele izinhlelo zokusebenza zokugoba ezisezingeni eliphezulu;
(6) Ukumelana okuhle kwezinga lokushisa eliphansi, nokungabi bikho kwezinga lokushisa eliphansi ngaphansi -30 ℃ noma -70 ℃;
(7) Inokusebenza okuhle kakhulu kokufakwa kwe-insulation, futhi ngenxa ye-conductivity yayo ephansi yokushisa, inomphumela ongcono wokuhlukanisa uma kuqhathaniswa nerabha nepulasitiki;
(8) Izakhiwo ezinhle ze-biocompatibility kanye ne-anticoagulant;
(9) Ukufakwa kukagesi okuhle kakhulu, ukumelana nesikhunta, nokuzinza kwe-UV.
Ama-elastomer e-polyurethane angakhiwa kusetshenziswa izinqubo ezifanayo nenjoloba evamile, njenge-plasticization, ukuxuba, kanye ne-vulcanization. Zingabuye zibunjwe ngendlela yerabha ewuketshezi ngokuthulula, ukubumba i-centrifugal, noma ukufafaza. Zingenziwa futhi zibe izinto eziyimbudumbudu futhi zakhiwe kusetshenziswa umjovo, i-extrusion, i-rolling, i-blow molding, nezinye izinqubo. Ngale ndlela, akugcini nje ukuthuthukisa ukusebenza kahle komsebenzi, kodwa futhi kuthuthukisa ukunemba kobukhulu nokubukeka komkhiqizo.
Isikhathi sokuthumela: Dec-05-2023