Graphical abstract Abstract Toughened epoxies reinforced by hybrid of kenaf/carbon fiber, untreated and treated, with the addition of liquid epoxidized natural rubber (LENR), were tested for their water absorption and thermal degradation. Water absorption testing was conducted based on ASTM D1037 to study the effects of kenaf fibre and carbon fibre on water uptake property. In the thermal analysis, the thermal degradation of the specimen was investigated towards heat. The test used a

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... etric analysis machine, model Mettler Toledo-TGA, at temperature range of 50 O C to 350 O C with an increment of 10 O C/min where the results showed the decreasing of degradation temperature when the treated fiber was used. The results also showed that the percentage of water absorptions for composites with the addition of LENR were lower compared to those of composites without LENR.