| 摘要 |
PROBLEM TO BE SOLVED: To provide polytetrafluoroethylene suitable for molding a porous polytetrafluoroethylene film by using a surfactant having high solubility in water and high volatility.SOLUTION: Provided is polytetrafluoroethylene: having non-molten secondary workability, a standard specific gravity of 2.160 or less, an average primary particle diameter of 150 nm or more, and a stress relaxation time of 500 seconds or more; obtained by emulsion polymerization of tetrafluoroethylene in the presence of s fluorine-containing surfactant having a Log POW of 3.4 or less; and having breaking strength of 29.7 N or more.SELECTED DRAWING: None |
