1
He ātete ngā rauemi polyurethane ki ngā pāmahana teitei? I te nuinga o te wā, kāore te polyurethane e ātete ki ngā pāmahana teitei, ahakoa he pūnaha PPDI noa, ko tōna rohe pāmahana mōrahi ka taea anake te tata ki te 150°. Kāore pea ngā momo polyester, polyether rānei noa e kaha ki te tu atu i ngā pāmahana neke atu i te 120°. Heoi, he polymer tino polar te polyurethane, ā, ki te whakatauritea ki ngā kirihou whānui, he ātete ake ki te wera. Nō reira, he mea tino nui te tautuhi i te awhe pāmahana mō te ātete pāmahana teitei, te wehewehe rānei i ngā whakamahinga rerekē.
2
Nā, me pēhea te whakapai ake i te pumau wera o ngā rauemi polyurethane? Ko te whakautu matua ko te whakanui ake i te tioata o te rauemi, pērā i te isocyanate PPDI tino auau i whakahuatia i mua ake nei. He aha te take e whakapai ake ai te tioata o te polymer i tōna pumau wera? E mōhiotia ana te whakautu e te katoa, arā, ko te hanganga te mea e whakatau ana i ngā āhuatanga. I tēnei rā, e hiahia ana mātou ki te whakamārama he aha te whakapai ake i te auau o te hanganga ngota ka hua ake ai te whakapainga o te pumau wera, ko te whakaaro matua nō te whakamāramatanga, te tātai rānei o te pūngao kore utu a Gibbs, arā, △G=H-ST. Ko te taha maui o G e tohu ana i te pūngao kore utu, ā, ko te taha matau o te whārite H ko te enthalpy, ko S ko te entropy, ā, ko T ko te pāmahana.
3
Ko te pūngao kore utu a Gibbs he ariā pūngao i roto i te thermodynamics, ā, he maha ngā wā he uara whanaunga tōna rahi, arā, ko te rerekētanga i waenga i ngā uara tīmatanga me ngā uara whakamutunga, nō reira ka whakamahia te tohu △ i mua i a ia, nā te mea kāore e taea te tiki tika, te whakaatu rānei i te uara tino. Ina heke te △G, arā, ina he kino, ko te tikanga ka taea e te tauhohenga matū te puta noa, te pai rānei mō tētahi tauhohenga e tumanakohia ana. Ka taea hoki tēnei te whakamahi hei whakatau mēnā kei te noho tonu te tauhohenga, kei te taea rānei te huri i roto i te thermodynamics. Ka taea te mārama ki te tohu, ki te tere rānei o te whakahekenga hei te kinetics o te tauhohenga tonu. Ko te H te tikanga he enthalpy, ka taea te mārama tata ki te pūngao ā-roto o tētahi ngota. Ka taea te matapae tata mai i te tikanga o te mata o ngā reta Hainamana, nā te mea kāore te ahi i te

4
Ko S te tohu o te entropy o te pūnaha, e mōhiotia whānuitia ana, ā, he mārama te tikanga tūturu. E pā ana ki te pāmahana T, e whakaaturia ana rānei i roto i ngā kupu o te pāmahana T, ā, ko tōna tikanga matua ko te nui o te koretake, te herekore rānei o te pūnaha iti moroiti. I tēnei wā, kua kite pea te hoa iti mātakitaki kua puta mai te pāmahana T e pā ana ki te ātete wera e kōrerohia ana e tātou i tēnei rā. Tukua ahau kia kōrero poto mō te ariā o te entropy. Ka taea te mārama kuware ki te entropy hei ritenga kē atu i te tioata. Ko te teitei ake o te uara entropy, ko te nui ake o te koretake me te pōrearea o te hanganga ngota. Ko te teitei ake o te auau o te hanganga ngota, ko te pai ake o te tioata o te ngota. Inaianei, me tapahi he tapawhā iti mai i te roera rapa polyurethane ka whakaarohia te tapawhā iti hei pūnaha katoa. He pumau tōna papatipu, me te whakaaro ko te tapawhā he 100 ngā ngota polyurethane (i te ao tūturu, he N te maha), nā te mea kāore i rerekē te papatipu me te rōrahi, ka taea e tātou te whakatau tata i te △G hei uara tau iti rawa, hei tata mutunga kore rānei ki te kore, kātahi ka taea te huri i te tātai pūngao kore utu a Gibbs ki ST=H, ko T te pāmahana, ā, ko S te entropy. Arā, ko te ātete wera o te tapawhā iti polyurethane he rite ki te enthalpy H, ā, he rite whakamuri ki te entropy S. He tikanga whakatau tata tēnei, ā, he pai ake te tāpiri i te △ i mua i a ia (ka whiwhi mā te whakataurite).
5
Ehara i te mea uaua ki te kite ko te whakapai ake i te tioatatanga kāore e taea anake te whakaiti i te uara entropy engari ka whakanui ake hoki i te uara enthalpy, arā, te whakanui ake i te ngota me te whakaiti i te denominator (T = H/S), he mea mārama mō te pikinga o te pāmahana T, ā, ko tētahi o ngā tikanga tino whai hua me te noa, ahakoa ko T te pāmahana whakawhiti karāhe, ko te pāmahana rewa rānei. Ko te mea me whakawhiti ko te auau me te tioatatanga o te hanganga ngota monomer me te auau whānui me te tioatatanga o te whakapakeketanga ngota teitei i muri i te whakakotahitanga he mea rārangi noa iho, ka taea te tata rite, te mārama rānei i roto i te huarahi rārangi. Ko te enthalpy H te nuinga o te wā e whai wāhi ana ki te pūngao ā-roto o te ngota, ā, ko te pūngao ā-roto o te ngota ko te hua o ngā hanganga ngota rerekē o te pūngao pūmanawa ngota rerekē, ā, ko te pūngao pūmanawa ngota ko te pūmanawa matū, he rite tonu, he raupapa te hanganga ngota, ko te tikanga he teitei ake te pūngao pūmanawa ngota, ā, he māmā ake te whakaputa i ngā āhuatanga tioatatanga, pērā i te wai e whakatōtō ana ki te hukapapa. Haunga tēnā, i whakaarohia noa e tātou he 100 ngā ngota polyurethane, ka pāngia hoki te ātete wera o tēnei roera iti e ngā kaha taunekeneke i waenga i ēnei ngota 100, pērā i ngā here hauwai ā-tinana, ahakoa kāore i te kaha pērā i ngā here matū, engari he nui te tau N, ko te whanonga mārama o te here hauwai ngota ngota ka taea te whakaiti i te nui o te koretake, te whakawhāiti rānei i te whānuitanga nekehanga o ia ngota polyurethane, nō reira he pai te here hauwai ki te whakapai ake i te ātete wera.