Synergistic visbreaking composition of peroxide and a hydroxylamine ester for increasing the visbreaking efficiency for polypropylene polymers at melt extrusion temperatures below 250° C. and its use in visbreaking polypropylene. The present invention is furthermore related to the use of such visbroken polypropylene polymers for producing melt blown non-wovens with improved barrier properties.

Synergistic visbreaking composition of peroxide and a hydroxylamine ester for increasing the visbreaking efficiency for polypropylene polymers at melt extrusion temperatures below 250° C. and its use in visbreaking polypropylene. The present invention is furthermore related to the use of such visbroken polypropylene polymers for producing melt blown non-wovens with improved barrier properties.

The invention relates to the use of at least one hydrogen peroxide in solid form to modify the rheology of a thermoplastic polymer when melted, specifically a polyolefin and particularly a polymer comprising at least one unit from propylene and, more particularly, polypropylene. The invention also relates to a method for modifying the rheology of a thermoplastic polymer when melted, specifically reducing viscosity when melted.

The invention relates to the use of at least one hydrogen peroxide in solid form to modify the rheology of a thermoplastic polymer when melted, specifically a polyolefin and particularly a polymer comprising at least one unit from propylene and, more particularly, polypropylene. The invention also relates to a method for modifying the rheology of a thermoplastic polymer when melted, specifically reducing viscosity when melted.

Provided is a method for producing low molecular weight polytetrafluoroethylene less likely to generate C6-C14 perfluorocarboxylic acids and salts thereof. The method for producing low molecular weight polytetrafluoroethylene includes: (1) feeding into an airtight container: high molecular weight polytetrafluoroethylene: and a gas mixture containing an inert gas and oxygen and having an oxygen content relative to the total of the inert gas and oxygen of 1 to 10 vol %; and (2) irradiating the high molecular weight polytetrafluoroethylene to provide low molecular weight polytetrafluoroethylene having a melt viscosity at 380° C. of 1.0×10.sup.2 to 7.0×10.sup.5 Pa.Math.s.

Provided is a method for producing low molecular weight polytetrafluoroethylene less likely to generate C6-C14 perfluorocarboxylic acids and salts thereof. The method for producing low molecular weight polytetrafluoroethylene includes: (1) feeding into an airtight container: high molecular weight polytetrafluoroethylene: and a gas mixture containing an inert gas and oxygen and having an oxygen content relative to the total of the inert gas and oxygen of 1 to 10 vol %; and (2) irradiating the high molecular weight polytetrafluoroethylene to provide low molecular weight polytetrafluoroethylene having a melt viscosity at 380° C. of 1.0×10.sup.2 to 7.0×10.sup.5 Pa.Math.s.

A fiber-reinforced polymer composition that comprises a polymer matrix that contains a propylene polymer is provided. The polymer matrix constitutes from about 30 wt. % to about 80 wt. % of the composition, and a plurality of long reinforcing fibers that are distributed within the polymer matrix. The fibers constitute from about 20 wt. % to about 70 wt. % of the composition. The polymer composition exhibits a spiral flow length of about 450 millimeters or more as determined in accordance with ASTM D3123-09, and after aging at a temperature of 150° C. for 1,000 hours, a Charpy unnotched impact strength greater than about 15 kJ/m.sup.2 as determined at a temperature of 23° C. in accordance with ISO Test No. 179-1:2010.

A fiber-reinforced polymer composition that comprises a polymer matrix that contains a propylene polymer is provided. The polymer matrix constitutes from about 30 wt. % to about 80 wt. % of the composition, and a plurality of long reinforcing fibers that are distributed within the polymer matrix. The fibers constitute from about 20 wt. % to about 70 wt. % of the composition. The polymer composition exhibits a spiral flow length of about 450 millimeters or more as determined in accordance with ASTM D3123-09, and after aging at a temperature of 150° C. for 1,000 hours, a Charpy unnotched impact strength greater than about 15 kJ/m.sup.2 as determined at a temperature of 23° C. in accordance with ISO Test No. 179-1:2010.

The disclosure relates to a method of making carbon fiber, the method comprising pyrolyzing poly(p-phenylene) (PPP) fiber at a temperature sufficient to convert PPP fiber substantially to carbon fiber. The disclosure also relates to pre-PPP polymer, methods for making PPP fiber from pre-PPP polymer and, in turn, making carbon fiber from PPP fiber.

The disclosure relates to a method of making carbon fiber, the method comprising pyrolyzing poly(p-phenylene) (PPP) fiber at a temperature sufficient to convert PPP fiber substantially to carbon fiber. The disclosure also relates to pre-PPP polymer, methods for making PPP fiber from pre-PPP polymer and, in turn, making carbon fiber from PPP fiber.