O le a le polyurethane fa'asusu-fa'amalolo

O le a le polyurethane fa'asusu-fa'amalolo

Polyurethane fa'asusu-fa'amalolo e tasi le vaega o le polyurethane o lona fofo o le susu o le siosiomaga. Ole polyurethane e mafai ona fa'asusu mo le susu e masani lava ona aofia ai le isocyanate-terminated pre-polymer. E mafai ona fa'aogaina ituaiga eseese o le mua'i-polymer e tu'uina atu ai meatotino mana'omia. Mo se faʻataʻitaʻiga, polyols polyether faʻamuta isocyanate e faʻaaogaina e tuʻuina atu ai le fetuutuunai lelei ona o le maualalo o le vevela suiga o tioata. O le tuʻufaʻatasia o vaega vaivai, e pei o le polyether, ma le vaega faigata, e pei o le polyurea, e maua ai le maaa lelei ma le fetuutuunai o faʻaofuofu. E le gata i lea, o meatotino o loʻo pulea foi e ala i le filifilia o ituaiga o isocyanates e tuʻufaʻatasia ma pre-polymer.

E lua ituaiga autu ole isocyanate ole aromatic isocyanate ma aliphatic isocyanate. Aromatic isocyanate e maualuga le gaoioi. Ae ui i lea, e leaga le umi o fafo ma le tele o lanu. O nisi fa'ata'ita'iga o isocyanates manogi o toluene diisocyanate(TDI) ma le 4,4'diphenylmethane diisocyanate(MDI). I le isi itu, o le aliphatic isocyanate, e pei o, isophorone diisocyanate (IPDI), e ofoina atu le lelei o le tau ma lanu taofi; ae ui i lea, o le gaioiga ole aliphatic isocyanate e maualalo, o lea e ono manaʻomia ai nisi faʻamalosi. O le mea lea, o ituaiga o isocyanate e taua tele e ausia ai meatotino manaʻomia. E le gata i lea, o mea faʻaopoopo, solvents, pigments, ma isi mea e mafai ona faʻaopoopo e faʻatatau i le faʻaoga. Ae ui i lea, o mea mataʻutia mo polyurethanes susu-faʻamalolo e tatau ona pulea ina ia leai se susu ina ia maua ai le mautu lelei o le teuina ma meatotino ata.

O le isi tulaga lelei o polyurethane susu-e mafai ona togafitia o le tasi lea vaega. O le mea lea, e faigofie ona faʻaoga talu ai e leai se fua faʻafefiloi talafeagai e manaʻomia, faʻatusatusa ile lua-vaega faʻapipiʻi. O le PU faʻamalolo susu e fesoʻotaʻi e ala i le tali atu o le Isocyanate-terminated pre-polymer ma le vai i le ea, maua ai amines ma sina vaega itiiti o le carbon dioxide. Mulimuli ane, o le tali atu o amine ma isi vaega o le isocyanate-terminated pre-polymer e tupu lea, e fai ai le sootaga o le urea.