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) Weight of falling ball impact test 2.13kg. The head makes the heavy bob of 10mmR fall from the height of 10 m The drying conditions of Iupilon / NOVAREX are indicated in Table 2･1-2

(Note) Please note that the grade of the polymer -alloy type sometimes differs in the dry ing conditions.

In order to dry the pellets of Iupilon / NOVAREX until the moisture content is lower than the above mentioned limit、 it is necessary to note the kind of the dryer, its performance and environment ( temperature and moisture). Fig. 2･1-1 is the example which shows the dry curve by the difference of the environment with the multi-tray hot air circulation dryer. The dry efficiency is decreased under high temperature, high humidity and it requires long time until the moisture content is lower than the limit. 

Prevention of moisture absorption in the hopper