GRANULATED FILLER-FREE POLYTETRAFLUOROETHYLENE POWDER AND A METHOD FOR PREPARATION THEREOF Russian patent published in 2003 - IPC

FIELD: polymer materials. SUBSTANCE: method consists in granulating filler- free optionally modified polytetrafluoroethylene in water at stirring in presence of organic fluid forming liquid- liquid phase interface with water. Polytetrafluoroethylene was prepared by suspension polymerization and has particle size at least 10 mcm and below 100 mcm. Granulation is effected in presence of nonionic or anionic surfactant. Powder according to invention shows high apparent density, small average particle size, low electrostatic charge, small natural slope, narrow size distribution, good flowability, and high degree of whiteness. EFFECT: improved performance characteristics. 17 cl, 4 dwg, 5 tbl _