Investigation of the physical, mechanical and morphological properties of the foam obtained from polylactic acid and microcrystalline cellulose

Foams made from poly-lactic acid, which is a natural polymer, have been introduced as an alternative to petroleum-based foams. However, the use of these foams faces limitations in terms of physical and mechanical characteristics. To improve the quality of poly-lactic acid foams, natural nucleating agents such as cellulose derivatives can be used. The effect of micro-crystalline cellulose as a nucleating agent in the production of poly-lactic acid/wood flour foam with azodicarbonamide foaming agent was investigated. The results revealed that by increasing the foaming agent content up to 3% and the nucleating agent content up to 4%, the density of the foam panels decreased by 45.52%. The reduction in density was accompanied by an increase in porosity, expansion rate, water absorption, and thickness swelling throughout all treatment levels (1 to 3% foaming agent and 1 to 4% nucleating agent), and this decrease in density led to a reduction in tensile and flexural strength and an increase in impact resistance. The morphological changes of the produced foams were also confirmed by scanning electron microscopy (SEM) images.