due to the thermoplastic behavior,pastillated and flaked grades may fuse,block or lump.this can be accelerated under any of the following conditions:1)above ambient temperature2)prolonged storage,3)pressure,stacking pallets ,or a combination of these conditions.this is particularly applicable for low melting point grades in order tdeo maintain the flake or pastille shape,we therefore recommend storing the material in a temperature controlled area,be careful with stacking material or applying pressure and preventing prolonged storage.it should be noted that lumping does not have a negative impact on the product specifications