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Bernardo García, Victoria Laguna Gutiérrez, Ester Rodríguez Pérez, Miguel Ángel 2020-04-06T07:29:46Z 2020-04-06T07:29:46Z 2019 Polym Int 2020; 69: 72–83 0959-8103 http://uvadoc.uva.es/handle/10324/40704 10.1002/pi.5920 72 1 83 Polymer International 69 1097-0126 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 spa info:eu-repo/semantics/openAccess Influence of the viscosity of poly(methyl methacrylate) on the cellular structure of nanocellular materials info:eu-repo/semantics/article