RT info:eu-repo/semantics/article T1 Influence of the viscosity of poly(methyl methacrylate) on the cellular structure of nanocellular materials A1 Bernardo García, Victoria A1 Laguna Gutiérrez, Ester A1 Rodríguez Pérez, Miguel Ángel AB Three different grades of poly(methyl methacrylate) (PMMA) with different rheological properties are used for the production of nanocellular materials using gas dissolution foaming. The influences of both the viscosity of the different polymers and the processing parameters on the final cellular structure are studied using a wide range of saturation and foaming conditions. Foaming conditions affect similarly all cellular materials. It is found that an increase of the foaming temperature results in less dense nanocellular materials, with higher cell nucleation densities. In addition, it is demonstrated that a lower viscosity leads to cellular polymers with a lower relative density but larger cell sizes and smaller cell nucleation densities, these differences being more noticeable for the conditions in which low solubilities are reached. It is possible to produce nanocellular materials with relative densities of 0.24 combined with cell sizes of 75 nm and cell nucleation densities of 1015 nuclei cm−3 using the PMMA with the lowest viscosity. In contrast, minimum cell sizes of around 14 nm and maximum cell nucleation densities of 3.5 × 1016 nuclei cm−3 with relative densities of 0.4 are obtained with the most viscous one. © 2019 Society of Chemical Industry SN 0959-8103 YR 2019 FD 2019 LK http://uvadoc.uva.es/handle/10324/40704 UL http://uvadoc.uva.es/handle/10324/40704 LA spa NO Polym Int 2020; 69: 72–83 DS UVaDOC RD 27-abr-2024