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oai:uvadoc.uva.es:10324/612732025-02-13T07:09:48Zcom_10324_1158com_10324_931com_10324_894col_10324_1242

Amezúa Arranz, Clara Santiago Calvo, Mercedes Rodríguez Pérez, Miguel Ángel 2023-08-31T09:12:06Z 2023-08-31T09:12:06Z 2023 European Polymer Journal, 2023, vol. 197, 112366 0014-3057 https://uvadoc.uva.es/handle/10324/61273 10.1016/j.eurpolymj.2023.112366 112366 European Polymer Journal 197 Producción Científica Isocyanate is a toxic substance that is one of the main reactants used in the conventional fabrication route for polyurethane foams. This study presents the synthesis of isocyanate-free polyurethane foams from cyclic carbonates and diamines using sodium bicarbonate as the foaming agent. Three different series of foams are synthesised using three types of sodium bicarbonates having different average particle sizes (i.e. 3, 13, and 22 µm) at four content levels (i.e. 5, 10, 15, and 20 wt% with respect to cyclic carbonate). The density, open-cell content, average cell size, normalised standard deviation of the cell size distribution, anisotropy, cell density and cell nucleation density are characterized for all the materials synthesized. In addition, a theoretical study of the expected densities is conducted to compare the theoretical values with the experimental densities obtained for the foams. Finally, the foams previously manufactured with high sodium-bicarbonate content are optimised by modifying the catalyst content from 0.5 to 2.0 wt% with respect to cyclic carbonate, thereby producing foams with lower densities. Nonisocyanate polyurethane foams having densities as low as 142 kg/m3 are fabricated. Ministerio de Ciencia e Innovación y Ministerio de Universidades (RTI2018 - 098749-B-I00, PID2021-127108OB-I00, TED2021-130965B-I00 y PDC2022-133391-I00) Junta de Castilla y León - UE-FEDER (VA202P20) application/pdf eng Elsevier info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by-nc-nd/4.0/ © 2023 The Authors Attribution-NonCommercial-NoDerivatives 4.0 Internacional Higiene industrial Materials science Free-isocyanate polyurethane foams Sodium bicarbonate Formulation optimization Espumas de poliuretano sin isocianatos Bicarbonato de sodio Optimización de la formulación 2211.02 Materiales Compuestos A new synthesis route to produce isocyanate-free polyurethane foams info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion https://www.sciencedirect.com/science/article/pii/S0014305723005499?via%3Dihub SI