Natural rubber latex foams (NRLFs) are widely used in comfort products such as mattresses and pillows. However, the synthesis of NRLFs needs the use of vulcanizing agents, such as sulfur, to cross-link the polymeric matrix, and thus, stabilize the sample. Therefore, in spite of the bioderived character of the natural latex, the final foam is hard to recycle. Nowadays, the industrial and academic interest on looking for more sustainable and environmentally friendly materials promotes the developing of new synthesis routes for these foams.

In this work, we develop non-crosslinked and bioderived NRLFs using egg white powder and native corn starch as stabilizer additives with the aim to promote new green alternatives to the conventional product. We obtain the foams from a two-stage foaming process in which the liquid blend is firstly aerated with a whipping machine and secondly dehydrated via microwave radiation so that water is quickly evaporated, and the foam is stabilized.

Herein, we present different series of flexible latex foams with open cellular structures and different cell sizes obtained by tuning the amount and type of stabilizer additive. Besides, we study the effect of the additives and the aeration on the liquid foam stability as well as the effect on the density and structure of the solid foam after microwave.