This data set contains two items: 1) Measurement data of the solid-state nanofoaming experiments at different foaming times (60s, 180s, 300s, 600s) and foaming temperatures (25deg, 40deg, 60deg, 80deg). Reported are: relative density rr, porosity p, cell nucleation density N0, average cell size f, and observed standard deviation SD in cell sizes. All measurements methods are summarised in the main manuscript. More details are given in the open access publication (https://doi.org/10.3390/polym8070265) of the Cellmat group at the University of Valladolid. 2) Code files for the void growth simulations in Matlab The theoretical framework is summarised in the main manuscript. More details can be found in the thesis of Van Loock (https://doi.org/10.17863/CAM.41889). See readme.txt file for further details.