Apha ngezantsi kukho imveliso ye-papi .
I-PIPI (CROUDE MDI) iveliswa ngendlela efanayo ne-MDI ngaphandle kokuba umyinge wenani le-Aniline kwi-Phydrochloric Acid incitshiswa ({0}} incitshiswe kumxube we-polyamine oqukethe inani elithile I-Diamine phantsi kwesenzo se-acid yeLewis, kwaye emva koko i-Polyamine I-Polnamine iphantsi kwempendulo yokufumana i-papi {{3} . ngokubanzi, inokufezekiswa ngokuhlengahlengiswa kwezinto ezimbini ze-aniline kwaye zinokwenziwa ngokulungelelanisa izixhobo ze-aminine kwaye IFomaldehyde, oko kukuthi, isixa sezinto {6} ., i-{10}}, i-{{ye-{10}, ngokubanzi i 1 . 6 ukuya {. I-Polyamine ye-Polyamine ifakwe kwi-MDI I-formaldehyde ye-Foures Ngokwesiqhelo, inkqubo yokuvelisa i-MDI kunye ne-papi iyamkelwa.