2026-05-05T21:03:17Zhttps://uvadoc.uva.es/oai/request

oai:uvadoc.uva.es:10324/258812021-06-24T07:47:49Zcom_10324_31661com_10324_952com_10324_894com_10324_1158com_10324_931col_10324_31662col_10324_1242

Highly anisotropic crosslinked HDPE foams with a controlled anisotropy ratio: Production and characterization of the cellular structure and mechanical properties Bernardo García, Victoria Laguna Gutiérrez, Ester López Gil, Alberto Rodríguez Pérez, Miguel Ángel Producción Científica In this paper a two-step foaming process was used to produce highly anisotropic foams with controlled anisotropy ratio. Anisotropic cellularmaterials are of great interest due to the enhanced mechanical properties that they show in the anisotropy direction. Therefore, the production of foams with high and controlled anisotropy ratios is an essential topic when it comes to designmaterialswith goodmechanical performance. In thiswork, high density polyethylene (HDPE) foams with anisotropy ratios larger than 3 have been produced. A foaming process consisting of two consecutive heating steps: pre-foaming and foaming, has been employed. Foaming kinetics at four different pre-foaming temperatures (145 °C, 155 °C, 170 °C and 180 °C) and at a constant foaming temperature (180 °C) have been performed. Results showed that the pre-foaming temperature is the key parameter that allows controlling the anisotropy ratio of the final foam. A relationship between the pre-foaming temperature, the number of cells and the anisotropy ratio has been established. Low pre-foaming temperatures lead to low numbers of cells, which eventually results in high anisotropy ratios. Mechanical properties in compression were measured and compared with the anisotropy of the cellular structure, being that the elastic modulus increases with the anisotropy ratio. 2017-09-24T14:58:16Z 2017-09-24T14:58:16Z 2017 info:eu-repo/semantics/article Materials and Design 114 (2017) 83–91 http://uvadoc.uva.es/handle/10324/25881 eng http://linkinghub.elsevier.com/retrieve/pii/S0264127516313491 info:eu-repo/semantics/restrictedAccess Elsevier Elsevier SI