Tessanan W.Phinyocheep P.Mahidol University2023-06-182023-06-182022-04-01Iranian Polymer Journal (English Edition) Vol.31 No.4 (2022) , 455-46910261265https://repository.li.mahidol.ac.th/handle/20.500.14594/84097The toughening modification of PLA was successfully performed by incorporating modified natural rubber (MNR). The MNR was obtained from chemical modification of natural rubber (NR) in a latex system through a two-step procedure; hydrogenation followed by epoxidation reaction. Different amounts of NR and MNR were mixed with PLA by a physical melt-blending procedure. As a result, blending MNR (5% by weight) with PLA could efficiently strengthen fracture resistance (18.89 kJ/m2) and stretchability (113.79%), approximately fivefold and 16-fold, respectively, compared to the neat PLA (3.58 kJ/m2 impact strength and 7.08% elongation-at-break). In comparison, impact strength (7.21 kJ/m2) and elongation-at-break (8.64%) of NR/PLA were found at the same weight ratio. The high toughening efficiency of MNR for PLA could be explained by their good compatibility of the two phases. The impact-fractured surface of the blend showed fine rubber particles and stretched-rubber fibrils in the scanning electron microscope (SEM) image. Furthermore, the optical properties in terms of light transmission of the MNR/PLA blend displayed higher transparency (74.62%) than the unmodified NR/PLA blend (34.34%). The obtained results suggest that the developed MNR will offer a potential application as a high impact modifier for PLA. Graphical abstract: [Figure not available: see fulltext.]Chemical EngineeringArticleSCOPUS10.1007/s13726-021-01000-02-s2.0-8511985746517355265