Since Iupilon / NOVAREX have an ester bond in the main chain, the hydrolysis occurs when heated with the moisture.
As a result, the physical properties, particularly the molecular weight and the impact strength are reduced. Also, the
preliminary drying before molding is necessary because the generation of silver streak and void at the appearance occur.
The moisture content in the pellets should be assumed to be 0.015~0.020% at the preliminary drying of Iupilon /
NOVAREX. The results of the molding at various moisture content are shown in Table 2･1-1. These results indicate that
the degradation of the impact strength in addition to the generation of defective appearance is very large. Therefore, it is
important to use the dried pellets that the moisture content is lower than the above mentioned limit to have a good
performance of Iupilon / NOVAREX.
(Note) Please note that the grade of the polymer -alloy type sometimes differs in the dry ing conditions.
Multi-tray hot air circulation dryer
Fig. 2･1-2 Drying conditions by the hopper dryer