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The development of biobased composites, in which non‐biobased additives or fillers are reinforced with the biobased polymers has been restricted to the addition of reinforcements to PLAs [48, 49]. When PLA is reinforced with fillers such as hydroxyapatite fibers (HAF) (up to 60 wt%), there is a significant improvement in their Young's modulus under compression molding conditions at 180 °C. The maximum value of Young's modulus attained was about 10 GPa for PLA/HAF composites [49]. For heavily loaded composites, a brittle behavior was observed and a covalent fiber–matrix interaction was revealed [49]. When PLA has been reinforced with carbon nanotubes (CNTs), there occurs a significant rise in the Young's modulus and hardness of the composites [50]. Purified CNTs are able to better disperse in a PLA matrix than nonpurified CNTs, thus resulting in better thermomechanical properties.