Abstract: A process for producing a thermoplastic polymer powder which comprises adding a polymer (B) and/or an inorganic compound (C) to a coagulation slurry or a powder of a thermoplastic polymer (A) obtained from emulsion polymerization and having a glass transition temperature Tg defined by the following equation (1), in an amount of 0.1-10 parts by weight to 100 parts by weight of the thermoplastic polymer (A), compacting the thermoplastic polymer (A) at a temperature in a range of (Tg-30) to (Tg+50).degree. C., and comminuting it:Tg=W.sub.1 .times.Tg.sub.1 +W.sub.2 .times.Tg.sub.2 + . . . +W.sub.n .times.Tg.sub.n ( 1)wherein n is the number of the monomers forming the thermoplastic polymer (A); W.sub.1, W.sub.2, . . . W.sub.n each represents weight fraction of each monomer i (i=1, 2, . . . n) in the polymer (A); and Tg.sub.1, Tg.sub.2, . . . Tg.sub.n each represents the glass transition temperature of the polymer composed of each monomer i.

Abstract: A method for producing a powdery and granular polymer by two coagulation steps comprising coagulating a latex of the polymer, the latex containing a sulfuric acid ester series and/or sulfonic acid series anionic surface active agents, with an acid to an amount of the polymer of 40 to 80 wt. % at a first coagulation step, and then bringing coagulation to completion with an acid or salt at a second coagulation step. According to the present invention, a powdery and granular polymer having a sharp particle size distribution and a high bulk specific gravity can be obtained.