01 Isimo esijwayelekile

I-MDI (i-diphenylmethane diisocyanic acid) iyinto eyenziwe nge-polyurethane eyenziwe yi-isocyanate, i-polyol kanye ne-ejenti yayo eyisizayo, esetshenziswa ezintweni zasekhaya, ezakhiweni, ezokuthutha nakwezinye izindawo.

I-MDI ibhekwa njengomunye wemikhiqizo emikhulu enezithiyo eziphezulu kakhulu embonini yamakhemikhali. Inqubo yokwenziwa kwe-isocyanate inde, okuhlanganisa ukusabela kwe-nitration, ukusabela kokunciphisa kanye nokusabela kwe-acidification.

Kunezinqubo ezimbili eziyinhloko zokukhiqiza ze-MDI: i-phosgenation kanye ne-non-phosgenation. Inqubo ye-phosgene ubuchwepheshe obujwayelekile bokukhiqiza ama-isocyanate ezimbonini njengamanje, futhi futhi yindlela kuphela engafeza ukukhiqizwa okukhulu kwama-isocyanate. Kodwa-ke, i-phosgene inobuthi obukhulu, futhi ukusabela kudinga ukwenziwa ngaphansi kwezimo ezinamandla ze-asidi, okudinga imishini nobuchwepheshe obuphezulu.

02 ukuhlunga

I-MDI ngokuvamile ihlukaniswe ngezigaba ezintathu: i-polymer MDI, i-pure MDI kanye ne-modified MDI:

I-MDI eyenziwe nge-polymer iyinto eluhlaza yokukhiqiza i-polyurethane hard foam kanye ne-semi-hard foam, futhi imikhiqizo yayo eqediwe isetshenziswa kabanzi esiqandisini, ezintweni zokushisa, ezingxenyeni zokuhlobisa izimoto nakwezinye izimboni.

I-Pure MDI isetshenziswa kakhulu ekukhiqizeni izinhlobo ezahlukene zama-polyurethane elastomers, ikakhulukazi esetshenziswa ekukhiqizeni ama-thermoplastic polyurethane elastomers, i-spandex, i-PU leather slurry, izinamathiseli zezicathulo, futhi isetshenziswa nasezintweni ze-microporous elastomer, njengezinsika, amathayi aqinile, i-self-crusting foam, ama-car bumpers, izingxenye zokuhlobisa zangaphakathi, kanye nokukhiqizwa kwama-cast polyurethane elastomers.

Njenge-derivative yemikhiqizo yochungechunge lwe-MDI, i-MDI eguquliwe iyisandiso sobuchwepheshe semikhiqizo ye-MDI emsulwa kanye ne-MDI eyenziwe nge-polymer evame ukusetshenziswa emakethe njengamanje, futhi inganikeza ukusetshenziswa okuyingqayizivele kanye nezakhiwo zokucubungula ngokuya ngomehluko womklamo wesakhiwo somkhiqizo kanye nenqubo yokwenziwa, ukuze isetshenziswe kabanzi kuma-bubble athambile, ama-elastomer, izimbozo, izinamathiseli kanye neminye imikhakha.

03 Uchungechunge lwezimboni oluphezulu noluphansi

Umthombo ongaphezulu we-oyela, igesi yemvelo, i-iron ore kanye nezinye izinsiza;

Izindawo eziphakathi nendawo zingamakhemikhali aphakathi kwezinto zokusetshenziswa kanye nemikhiqizo yokugcina engezansi, emele i-WH Chemical, i-WX petrochemical, njll.

Okulandelayo yimikhiqizo yamakhemikhali yokugcina, njengepulasitiki, irabha, izibulala-zinambuzane, umanyolo, njll., emele inkampani i-JF Technology, amathayi e-LL, amakhemikhali e-RL, i-HR Hengsheng, njll.

04 Ukuhlaziywa kwesidingo kanye nomehluko emakethe

I-polyurethane ekhiqizwa yi-MDI inezinhlobo eziningi zezicelo ezingezansi, ezisetshenziswa kakhulu embonini yokwakha, embonini yasekhaya, ezintweni zikagesi zasekhaya, embonini yezokuthutha, embonini yezicathulo, njll. Ngakho-ke, ukusetshenziswa kwe-MDI kuhlobene kakhulu nezinga lokuchuma komnotho womhlaba wonke.

Ngokombono womhlaba wonke, isakhiwo sokusetshenziswa kwe-MDI eyenziwe nge-polymer ngo-2021 ngokuyinhloko: 49% embonini yokwakha, 21% wezinto zasekhaya, 17% wezinamathiseli, kanye no-11% wezimoto.

Ngokombono wasekhaya, ingxenye yesakhiwo sokusetshenziswa kwe-MDI esenziwe nge-polymer ngo-2021 ikakhulukazi: u-40% wezimpahla ezimhlophe, u-28% embonini yokwakha, u-16% wezinamathiseli, kanye no-7% wezimoto.

05 Iphethini yokuncintisana

Uhlangothi lokuphakelwa kwe-MDI luveza iphethini yokuncintisana ye-oligopoly. Kunabakhiqizi abayisishiyagalombili abakhulu be-MDI emhlabeni, kanti abakhiqizi abathathu abaphezulu ngomthamo yi-WH Chemical, i-BASF kanye ne-Covestro, lapho amandla ahlanganisiwe amabhizinisi amathathu enza okungaphezu kwama-60% wamandla okukhiqiza emhlabeni. Phakathi kwawo, i-WH Chemical iyibhizinisi elihamba phambili embonini ye-MDI yaseShayina kanye nebhizinisi elikhulu kunawo wonke lokukhiqiza i-MDI emhlabeni.