Increasing the temperature from 140 to 160 C almost halved the hardness of the extruded products, although the hardness increased from 160 to 180 C (Table 3). This finding correlated positively with the product density values (r = 0.59) showing that as expected denser products are harder The tendency to increase hardness at higher temperature (180 C) may be due to the higher melt temperature that has caused changes in the chemistry of the melt.