. In relation with WG-based bioplastics, three different regions may clearly be distinguished in the reference (0 wt.% formic acid) sample: (a) during the 15 first minutes, approximately, torque does not increase significantly, as this region stands for an induction period, which was seen to decrease as mixing speed was raised (not shown here); (b) in the second region, which extends over a time interval of 5 min, torque undergoes an exponential increase up to a maximum value of about 40 N m; and (c) torque finally decays, whilst seems to tend to a constant value.