Novel polytetrafluoroethylene fine powder
AssigneeDaikin Kogyo Co., Ltd.
InventorsJyuzaemon Hoashi, Syozo Fumoto, Kiyoshi Oshita
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Abstract
Polytetrafluoroethylne fine powder is disclosed having an average molecular weight of at least 6,000,000, an amorphous index larger than 0.1 and a number average primary particle size of 0.1 to 0.8 micron, and further having a clear endothermic peak at a temperature of 347.degree..+-.3.degree. C. and another endothermic peak or shoulder at a temperature between 330.degree. C. and the temperature of said clear endothermic peak on a crystalline melting chart recorded by a differential scanning calorimeter. An unsintered article is made which is sintered and expanded at a temperature higher than the melting point of the polytetrafluoroethylene to give a porous article having improved properties.
Claims8
A polytetrafluoroethylene fine powder having an average molecular weight of at least 6,000,000, an amorphous index larger than 0.1 and a number average primary particle size of 0.1 to 0.8 micron and further having a first clear endothermic peak at a temperature of 347.+-.3.degree. C. and a second endothermic peak or shoulder at a temperature between 330.degree. C. and the temperature of said first endothermic peak on a crystalline melting chart recorded by a differential scanning calorimeter.
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