I-polyurethane elastomers yiklasi ebalulekileyo yezixhobo zepolymer eziphezulu zokusebenza. Ngeempawu zabo ezikhethekileyo zomzimba kunye neekhemikhali kunye nokusebenza okugqwesileyo okugqwesileyo, bahlala kwindawo ebalulekileyo kwishishini lanamhlanje. Ezi zixhobo zisetyenziswa ngokubanzi kwiindawo ezininzi zokuvelisa eziphezulu, ezifana ne-aerospace, iimoto eziphezulu, umatshini ochanekileyo, izixhobo zombane kunye nezixhobo zonyango, ngenxa yokuqina kwazo okulungileyo, ukuxhathisa ukunxiba, ukuxhathisa ukubola kunye nokuguquguquka kokucubungula. Ngokuqhubela phambili kwenzululwazi kunye nobuchwepheshe kunye nokuphuculwa okuqhubekayo kweemfuno zokusebenza kwezinto kwishishini lokuvelisa, uyilo oluphezulu lwe-polyurethane elastomers lube yinto ephambili ekuphuculeni ixabiso lesicelo sabo. Kwishishini lemveliso ephezulu, iimfuno zokusebenza kwezixhobo ziya ziba nzima ngakumbi. Njengomgangatho ophezulu wokusebenza, ukuyila kunye nokusetyenziswa kwe-polyurethane elastomers kufuneka kuhlangabezane nemigangatho ethile yobugcisa. Ukusetyenziswa kwe-polyurethane elastomers kwimveliso ephezulu ijongene nemingeni emininzi, kubandakanywa nokulawulwa kweendleko, ukuphunyezwa kobugcisa kunye nokwamkelwa kweemarike. Nangona kunjalo, ngeenzuzo zayo zokusebenza, i-polyurethane elastomers idlale indima ebalulekileyo ekuphuculeni ukusebenza kunye nokukhuphisana kwemveliso yokuvelisa. Ngophando olunzulu kule mimandla yesicelo, inokubonelela ngenkxaso eqinile yokuphucula ngakumbi ukuyila kwezinto kunye nokwandisa izicelo.

 

Uyilo oluphezulu lwe-polyurethane elastomers

 

Ukwakhiwa kwezinto kunye neemfuno zokusebenza

I-polyurethane elastomers yiklasi yezixhobo zepolymer ezinomsebenzi ogqwesileyo. Ubukhulu becala zenziwe ngamacandelo amabini asisiseko: i-polyether kunye ne-isocyanate. Ukukhethwa kunye nobungakanani bala macandelo anempembelelo ebalulekileyo ekusebenzeni kwezinto zokugqibela. I-polyether idla ngokuba lelona candelo lithambileyo le-polyurethane elastomers. Isakhiwo sayo se-molecular iqukethe amaqela e-polyol, anokubonelela nge-elasticity enhle kunye nokuguquguquka. I-Isocyanate, njengenxalenye ephambili yecandelo elinzima, inoxanduva lokuphendula nge-polyether ukwenza amaketanga e-polyurethane, ukwandisa amandla kunye nokugqoka ukuchasana kwezinto. Iindidi ezahlukeneyo ze-polyethers kunye ne-isocyanates zineekhemikhali ezahlukeneyo kunye neempawu zomzimba. Ngoko ke, ekuyilweni kwe-polyurethane elastomers, kuyimfuneko ukuba ukhethe ngokufanelekileyo kwaye ulungelelanise la macandelo ngokweemfuno zesicelo ukufezekisa izikhombisi zokusebenza ezifunekayo. Ngokubhekiselele kwiimfuno zokusebenza, i-polyurethane elastomers kufuneka ibe neempawu ezininzi eziphambili: ukuxhatshazwa kokugqoka, ukuqina, ukuguga, njl njl. Ngokukodwa xa isetyenziswe kwiindawo eziphezulu zokunxiba, ezifana neenkqubo zokumisa iimoto kunye nezixhobo zoshishino, ukuxhathisa okulungileyo kunokwandisa kakhulu ubomi benkonzo yemveliso. I-Elasticity yenye yeepropathi ezingundoqo ze-polyurethane elastomers. Inquma ukuba izinto eziphathekayo zinokubuyela ngokukhawuleza kwimilo yayo yangaphambili ngexesha lokuguqulwa kunye nokubuyisela. Isetyenziswa kakhulu kwii-seals kunye ne-shock absorbers. Ukuchasana nokuguga kubhekisela kwikhono lezinto eziphathekayo ukugcina ukusebenza kwayo emva kokusetyenziswa kwexesha elide okanye ukuvezwa kweendawo ezinzima (ezifana nemitha ye-ultraviolet, umswakama, utshintsho lokushisa, njl.), Ukuqinisekisa ukuba izinto eziphathekayo zigcina ukusebenza okuzinzile kwizicelo eziphathekayo.

 

IziCwangciso zoPhuculo loYilo

Uyilo oluphezulu lwe-polyurethane elastomers yinkqubo entsonkothileyo kunye nethambileyo efuna ukuqwalaselwa okubanzi kwezicwangciso zokuphucula uyilo oluninzi. Ukulungiswa kwesakhiwo seemolekyuli linyathelo eliphambili ekuphuculeni ukusebenza kwezinto. Ngokulungelelanisa i-molecular chain structure ye-polyurethane, njengokwandisa iqondo lokuwela, amandla omatshini kunye nokumelana nokunxiba kwezinto kunokuphuculwa kakhulu. Ukunyuka kwinqanaba le-crosslinking kuvumela ukuba isakhiwo sothungelwano esizinzile ngakumbi ukuba senziwe phakathi kwamaketanga eemolekyuli zezinto eziphathekayo, ngaloo ndlela kuphuculwe amandla ayo onke kunye nokuqina. Ngokomzekelo, ngokusebenzisa i-polyisocyanate reactants okanye ukwazisa i-agent e-crosslinking, i-degree of crosslinking inokunyuswa ngokufanelekileyo kwaye ukusebenza kwezinto eziphathekayo kunokulungiswa. Ukulungiswa komlinganiselo wecandelo nako kubalulekile. Umlinganiselo we-polyether kunye ne-isocyanate uchaphazela ngokuthe ngqo i-elasticity, ubunzima kunye nokuxhatshazwa kokugqoka kwezinto. Ngokubanzi, ukwandisa umlinganiselo we-isocyanate kunokonyusa ukuqina kunye nokumelana nokunxiba kwezinto, kodwa kunokunciphisa ukuqina kwayo. Ngoko ke, kuyimfuneko ukulungisa ngokuchanekileyo umlinganiselo wezo zimbini ngokweemfuno zangempela zesicelo ukufezekisa ibhalansi engcono yokusebenza. Ukongeza kokulungiswa kwesakhiwo se-molecular kunye nomlinganiselo wecandelo, ukusetyenziswa kwezongezo kunye nee-agent zokuqinisa nazo zinempembelelo enkulu ekusebenzeni kwezinto. I-Nanomatadium, njenge-nano-silicon kunye ne-nano-carbon, inokuphucula kakhulu ukusebenza okubanzi kwee-polyurethane elastomers. I-Nanomaterials iphucula iipropathi zoomatshini kunye nokuchasana kokusingqongileyo kwezixhobo ngokunyusa amandla abo, ukuxhathisa ukunxiba kunye nokuchasana nokuguga.

 

 

Ukuphuculwa kwenkqubo yamalungiselelo

Ukuphuculwa kwenkqubo yokulungiselela enye yeendlela ezibalulekileyo zokuphucula ukusebenza kwe-polyurethane elastomers. Ukuqhubela phambili kwitekhnoloji ye-polymer synthesis ibe nempembelelo enkulu ekulungiseleleni i-polyurethane elastomers. Iindlela zangoku zepolymer synthesis, ezifana nokubumba inaliti yokusabela (RIM) kunye netekhnoloji yoxinzelelo oluphezulu lwepolymerization, inokufikelela kulawulo oluchanekileyo ngakumbi ngexesha lenkqubo yokudibanisa, ngaloo ndlela iphucula ubume bemolekyuli kunye nokusebenza kwezinto. Itekhnoloji yokubumba itekhnoloji yokubumba i-reaction inokuphucula kakhulu ukusebenza kakuhle kwemveliso kunye nokufezekisa ukufana kwezinto ezingcono kunye nokungaguquguquki ngexesha lenkqubo yokubumba ngokuxuba ngokukhawuleza i-polyether kunye ne-isocyanate phantsi koxinzelelo oluphezulu kunye nokuzitofa kwi-mold. Itekhnoloji yoxinzelelo oluphezulu lwepolymerization inokuphucula ingxinano kunye namandla ezinto kwaye iphucule ukuxhathisa ukunxiba kunye nokumelana nokuguga ngokuqhuba ukuphendula kwepolymerization phantsi koxinzelelo oluphezulu. Ukuphuculwa kokubumba kunye nokucubungula iteknoloji yinto ephambili ekuphuculeni ukusebenza kwe-polyurethane elastomers. Iinkqubo zokubumba ushicilelo olushushu lwemveli ziye zathatyathelw' indawo ngobuchule bokubumba obuphambili benaliti kunye nobuchwephesha bokubumba. Ezi nkqubo ezintsha azikwazi nje ukuphucula ukusebenza kwemveliso, kodwa ziphinda zifezekise ulawulo oluchanekileyo ngexesha lenkqubo yokubumba ukuqinisekisa umgangatho kunye nokusebenza kwezinto eziphathekayo. Itekhnoloji yokubumba itekhnoloji inokufezekisa ukubumba okuchanekileyo kweemilo ezintsonkothileyo kunye nokunciphisa inkunkuma yezinto ngokufudumeza imathiriyeli ekrwada ye-polyurethane kwisimo esityhidiweyo kwaye ifakwe kwi-mold. Itekhnoloji yokubumba i-Extrusion ifudumeza kwaye inyanzela imathiriyeli ye-polyurethane ngaphandle kwe-extruder, yenze imicu yezinto eziqhubekayo okanye iityhubhu ngokupholisa kunye nokuqina. Ifanelekile kwimveliso enkulu kunye nokulungiswa okulungiselelwe .

 

Ukusetyenziswa kwe-polyurethane elastomers kwimveliso ephezulu

 

I-Aerospace

Kwintsimi ye-aerospace, i-polyurethane elastomers isetyenziswa ngokubanzi kumacandelo amaninzi abalulekileyo, njengama-seal kunye ne-shock absorbers, ngenxa yokusebenza kwabo okugqwesileyo. Umzi-mveliso we-aerospace uneemfuno ezinzima kakhulu ekusebenzeni kwezinto, ezibandakanya ukuxhathisa ubushushu obuphezulu, ukuxhathisa ukukhathala, ukuxhathisa ukubola kweekhemikhali, ukumelana nokunxiba, njl njl. Ukusebenza okuphezulu kwe-polyurethane elastomers kule miba kuyenza enye yezinto eziyimfuneko kwintsimi ye-aerospace. Thatha amatywina njengomzekelo. Kwi-fuel system yezithuthi ze-aerospace, izitywina kufuneka zigcine ukutywinwa okusebenzayo phantsi kobushushu obugqithisileyo kunye neemeko zoxinzelelo. Inkqubo ye-fuel yezithuthi ze-aerospace ihlala ibonakaliswe kubushushu obuphezulu, uxinzelelo oluphezulu kunye nemithombo yeendaba ezonakalisayo. Ngoko ke, izitywina akufanele zixhathise kuphela ukushisa okuphezulu, kodwa kunye nokubola kweekhemikhali. I-polyurethane elastomers, ingakumbi i-polyurethanes esebenza kakuhle kakhulu enyangelwe kumaqondo obushushu aphezulu, inokumelana nobushushu obuphezulu kwaye inokumelana neendawo zokusebenza ezingaphezulu kwama-300°C. Ngelo xesha, i-elasticity egqwesileyo ye-polyurethane elastomers ibenza bakwazi ukuzalisa ngokufanelekileyo iindawo ezingaqhelekanga kwaye baqinisekise ukuzinza kunye nokuthembeka kwezitywina ekusebenziseni ixesha elide. Umzekelo, amatywina asetyenziswa kwiziphekepheke zeNASA kunye nezikhululo zasejukujukwini zisebenzisa i-polyurethane elastomers, ebonisa ukusebenza kokutywina okugqwesileyo kunye nokuqina kwiimeko ezigqithisileyo. Enye i-shock absorbers. Kwi-aerospace, i-shock absorbers isetyenziselwa ukunciphisa impembelelo ye-vibration yesakhiwo kunye nokothuka kumacandelo abalulekileyo. I-polyurethane elastomers idlala indima ebalulekileyo kwizicelo ezinjalo. Ukunwebeka kwabo okugqwesileyo kunye nokukwazi ukufunxa kakuhle amandla kubenza bakwazi ukuthintela ngokufanelekileyo kwaye banciphise ukungcangcazela kunye nokothuka, ngaloo ndlela bekhusela ubume kunye nezixhobo zombane ze-aerospace.

 

 Ishishini leemoto eziphezulu

Kwimizi-mveliso yeemoto eziphezulu, ukusetyenziswa kwe-polyurethane elastomers kuye kwaba yinto ebalulekileyo ekuphuculeni ukusebenza kwesithuthi kunye nokuthuthuzela. Ngenxa yokusebenza kwayo okugqwesileyo okugqwesileyo, i-polyurethane elastomers isetyenziswa ngokubanzi kumacandelo amaninzi aphambili eemoto, kubandakanywa neenkqubo zokufunxa ukothuka, izitywina, iindawo zangaphakathi, njl.njl. Ukuthatha i-absorbers yomothuko kwinkqubo yokunqunyanyiswa kweemoto eziphezulu njengomzekelo, ukusetyenziswa kwe-polyurethane elastomers kuye kwaphucula kakhulu induduzo yokuqhuba kunye nokuzinza kokusingatha isithuthi. Kwinkqubo yokunqunyanyiswa, i-polyurethane elastomers ifunxa ngempumelelo impembelelo kunye nokungcangcazela endleleni kwaye inciphise ukushukuma komzimba wesithuthi ngobuchule bazo obugqwesileyo kunye neempawu zokufunxa ukothuka. I-elasticity egqwesileyo yesi sixhobo iqinisekisa ukuba inkqubo yokumiswa kwesithuthi inokuphendula ngokukhawuleza phantsi kweemeko ezahlukeneyo zokuqhuba kwaye inike amava okuqhuba kakuhle kwaye akhululekile. Ngokukodwa kwiimodeli zodidi oluphezulu, i-high-performance absorbers yothuso usebenzisa i-polyurethane elastomers inokuphucula ngokubonakalayo induduzo yokukhwela kwaye ihlangabezane neemfuno zokuqhuba amava aphezulu. Kwiimoto eziphakamileyo eziphezulu, ukusebenza kwezitywina kuchaphazela ngokuthe ngqo ukukhutshwa kwesandi, ukufudumala ukushisa kunye nokusebenza kwamanzi kwisithuthi. I-polyurethane elastomers isetyenziswa kakhulu ekutywineni iingcango zemoto kunye neefestile, amagumbi enjini kunye neekhareji zangaphantsi ngenxa yokutywinwa kwazo okugqwesileyo kunye nokumelana nemozulu. Abavelisi beemoto eziphezulu basebenzisa i-polyurethane elastomers njengezitywina zomnyango ukuphucula ukugquma kwesandi sesithuthi kunye nokunciphisa ukungena kwengxolo yangaphandle.