PURPOSE: To obtain a polymer powder having improved particle diameter distribution and suitably for storage by coagulating a vinyl polymer latex to which a coagulant has been added in a cascade of vessels under specified conditions.
CONSTITUTION: A vinyl polymer latex having a polymer solids content of 10-70 wt.% and a particle diameter of 50-1,000 nm and delivered from a storage container 1 is heated to 50-120°C and introduced to a precipitation cascade K1, and a coagulant from a storage container 7 is added thereto, intimately mixed therewith for 10-60 min, and intensively mixed by allowing it to reside in each of precipitation cascade K2 to K4 at an average residence time of 10-60 min. Next, this vinyl polymer latex is introduced into a filter 8 to separate an agglomerated polymer, and the serum containing the agglomerant is recirculated to a storage container 6 through a pipe 10. Then, the separated polymer is dried to obtain a thermoplastically processable vinyl polymer powder.
KARURUUHAINTSU OTSUTO
BORUFUGANGU HERITSUHI
OTSUTO KOTSUHO
ARUFUREETO PISHIYUCHIYAN
DEIITAA BITSUTOMAN
