Process for preparing polytetrafluoroethylene granular powder containing filler and polytetrafluoroethylene granular prepared by the same

摘要

A process for preparing a filler-containing PTFE granular powder, which comprises mixing uniformly a PTFE powder having an average particle size of not more than 100 mu m and a (semi-)hydrophilic filler which is surface-treated with an organosilane of the formula: <IMAGE> in a two-phase liquid medium comprising water and a water-insoluble organic liquid having a surface tension of not more than 35 dynes/cm at 25 DEG C. Accordingly to the process, the separation of filler can be avoided, and a colorless molded article can be provided.