VYLOPET® must be pre-dried prior to molding.
It is recommended for pre-drying to use a hopper dryer, but alternatively,
a shelf dryer may perform sufficient drying.
For applicable drying conditions, please refer to the summary in Table
the diagrams of drying time vs. water absorption when dried at 140°C.
Please set appropriate drying conditions so as to keep the water absorption
less than 0.025%.
[Fig.2] shows the diagrams
of pellets exposure time vs. water absorption. Pellets will absorb
water when exposed in the air. For pellets exposed in the air for
30~40 minutes or more, please re-dry them prior to use.
The longer pellets are exposed in the hot and high humidity air
like the condition (A), the more they easily absorb water. Accordingly,
during hot and high humidity time like the rainy or summer season,
please treat pellets carefully to avoid their moisture re-absorbing.
|[Fig.1] Drying time vs. water absorption at 140°C
|[Fig.2] Exposure time of pellets vs. water
[Fig. 3] shows changes
in the holding rate of solution viscosity when the water absorption
in pellets changes.
When the water absorption in pellets is high, resins will be hydrolyzed,
and resultantly, the solution viscosity of moldings will be significantly
|[Fig.3] Holding rate of solution viscosity vs. water
Please remember to process moldings with the water
absorption not more than 0.025 %.