Various aspects of the present disclosure are directed toward apparatuses, systems, and methods that include a cord that is flexible and elongated defining a length. The cord may include a core having a porous surface and a porosity-reducing element on at least a portion of the core.

Various aspects of the present disclosure are directed toward apparatuses, systems, and methods that include a cord that is flexible and elongated defining a length. The cord may include a core having a porous surface and a porosity-reducing element on at least a portion of the core.

The disclosure provides a method for producing low molecular weight polytetrafluoroethylene containing less C6-C14 perfluorocarboxylic acids or salts thereof. The method for producing low molecular weight polytetrafluoroethylene includes: (1) irradiating high molecular weight polytetrafluoroethylene to provide low molecular weight polytetrafluoroethylene having a melt viscosity of 1.0×10.sup.2 to 7.0×10.sup.5 Pa.Math.s at 380° C.; and (2) irradiating the low molecular weight polytetrafluoroethylene to a dose that does not decompose the low molecular weight polytetrafluoroethylene.

The disclosure provides a method for producing low molecular weight polytetrafluoroethylene containing less C6-C14 perfluorocarboxylic acids or salts thereof. The method for producing low molecular weight polytetrafluoroethylene includes: (1) irradiating high molecular weight polytetrafluoroethylene to provide low molecular weight polytetrafluoroethylene having a melt viscosity of 1.0×10.sup.2 to 7.0×10.sup.5 Pa.Math.s at 380° C.; and (2) irradiating the low molecular weight polytetrafluoroethylene to a dose that does not decompose the low molecular weight polytetrafluoroethylene.

The present disclosure provides poly(tetrafluoroethylene) (PTFE) microparticles with a Dv50 of about 20 μm to about 30 mm and a specific surface area (SSA) of at least about 3.0 m.sup.2/g when measured by a multipoint BET method of ISO 9277. Such PTFE microparticles can be obtained via a method including thermomechanically degrading scrap PTFE in the presence of air and/or oxygen and reducing the particle size of the resultant degraded PTFE.

The present disclosure provides poly(tetrafluoroethylene) (PTFE) microparticles with a Dv50 of about 20 μm to about 30 mm and a specific surface area (SSA) of at least about 3.0 m.sup.2/g when measured by a multipoint BET method of ISO 9277. Such PTFE microparticles can be obtained via a method including thermomechanically degrading scrap PTFE in the presence of air and/or oxygen and reducing the particle size of the resultant degraded PTFE.

A method of producing a fluorine-containing compound is a method of producing a compound (30) having partial structure (3) by an insertion reaction of compound (20) into compound (10) that has partial structure (1), in the presence of an ionic catalyst formed from a specific monovalent anion and a counter cation. In the formulas, * represents a bonding site, and X.sup.1 and R.sup.1 to R.sup.4 each independently represents a hydrogen atom, a fluorine atom, a chlorine atom, or an organic group having a carbon number of 1 to 20 which may have a substituent.

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A fluorine-containing resin particle contains 0 or more and 30 or less carboxyl groups per 10.sup.6 carbon atoms and 0 ppm or more and 3 ppm or less of a basic compound.

A fluorine-containing resin particle contains 0 or more and 30 or less carboxyl groups per 10.sup.6 carbon atoms and 0 ppm or more and 3 ppm or less of a basic compound.

A fluorine-containing resin particle contains 0 or more and 30 or less carboxyl groups per 10.sup.6 carbon atoms and 0 ppm or more and 3 ppm or less of a basic compound.