The carbon fiber precursor contains a crosslinked acrylamide-based polymer and has a gel fraction of 5% or more.

A method of producing a functionalized material that extracts metal ions from solution, the method comprising: (i) providing a precursor material having nitrile groups appended to its surface; and (ii) reacting said nitrile groups with hydroxylamine or a derivative thereof in the presence of a polar aprotic solvent at a temperature of 60-80° C. for at least 1 hour, to convert at least a portion of said nitrile groups to amidoxime and imide dioxime groups, followed by reaction with a base capable of hydrolyzing any remaining nitrile groups to carboxylic acid groups; wherein said functionalized material has a higher uranium absorption capacity than a functionalized material produced under same conditions except that the nitrile groups are reacted with hydroxylamine in only a protic solvent. The invention is also directed to functionalized materials produced by the above-described method, and methods for using the functionalized material for extracting metal ions from metal-containing solutions.

The invention relates to a method for thermally stabilizing melt-spun PAN precursors. For this purpose, the invention provides a continuous method for producing a thermally stabilized multifilament thread made of a meltable copolymer of polyacrylonitrile (PAN), wherein a pre-stabilized multifilament thread is thermally stabilized and in the process at least temporarily stretched. The invention additionally relates to a thermally stabilized multifilament thread which can be obtained according to a corresponding method and to a carbon fiber which is made of the correspondingly thermally stabilized multifilament thread.

A method of producing a functionalized material that extracts metal ions from solution, the method comprising: (i) providing a precursor material having nitrile groups appended to its surface; and (ii) reacting said nitrile groups with hydroxylamine or a derivative thereof in the presence of a polar aprotic solvent at a temperature of 60-80° C. for at least 1 hour, to convert at least a portion of said nitrile groups to amidoxime and imide dioxime groups, followed by reaction with a base capable of hydrolyzing any remaining nitrile groups to carboxylic acid groups; wherein said functionalized material has a higher uranium absorption capacity than a functionalized material produced under same conditions except that the nitrile groups are reacted with hydroxylamine in only a protic solvent. The invention is also directed to functionalized materials produced by the above-described method, and methods for using the functionalized material for extracting metal ions from metal-containing solutions.

A method of manufacturing a string 10 for use in a racket includes: (A) preparing an untreated string; and (B) irradiating the untreated string with radioactive rays. Preferably, the untreated string is irradiated with gamma rays. A preferable irradiation amount of the radioactive rays is greater than or equal to 250 kGy but less than or equal to 2000 kGy. Preferably, a material of the untreated string is polyester. Alternatively, the material of the untreated string may be nylon.

A method of producing a functionalized material that extracts metal ions from solution, the method comprising: (i) providing a precursor material having nitrile groups appended to its surface; and (ii) reacting said nitrile groups with hydroxylamine or a derivative thereof in the presence of a polar aprotic solvent at a temperature of 60-80 C. for at least 1 hour, to convert at least a portion of said nitrile groups to amidoxime and imide dioxime groups, followed by reaction with a base capable of hydrolyzing any remaining nitrile groups to carboxylic acid groups; wherein said functionalized material has a higher uranium absorption capacity than a functionalized material produced under same conditions except that the nitrile groups are reacted with hydroxylamine in only a protic solvent. The invention is also directed to functionalized materials produced by the above-described method, and methods for using the functionalized material for extracting metal ions from metal-containing solutions.

A method of producing a functionalized material that extracts metal ions from solution, the method comprising: (i) providing a precursor material having nitrile groups appended to its surface; and (ii) reacting said nitrile groups with hydroxylamine or a derivative thereof in the presence of a polar aprotic solvent at a temperature of 60-80 C. for at least 1 hour, to convert at least a portion of said nitrile groups to amidoxime and imide dioxime groups, followed by reaction with a base capable of hydrolyzing any remaining nitrile groups to carboxylic acid groups; wherein said functionalized material has a higher uranium absorption capacity than a functionalized material produced under same conditions except that the nitrile groups are reacted with hydroxylamine in only a protic solvent. The invention is also directed to functionalized materials produced by the above-described method, and methods for using the functionalized material for extracting metal ions from metal-containing solutions.

The invention relates to a method for thermally stabilizing melt-spun PAN precursors. For this purpose, the invention provides a continuous method for producing a thermally stabilized multifilament thread made of a meltable copolymer of polyacrylonitrile (PAN), wherein a pre-stabilized multifilament thread is thermally stabilized and in the process at least temporarily stretched. The invention additionally relates to a thermally stabilized multifilament thread which can be obtained according to a corresponding method and to a carbon fiber which is made of the correspondingly thermally stabilized multifilament thread.

Textiles are provided that include fibrous cellulosic materials having an -cellulose content of less than about 93%, the fibrous materials being spun, woven, knitted, or entangled. The fibrous cellulosic materials can be irradiated with a dose of ionizing radiation that is sufficient to increase the molecular weight of the cellulosic materials without causing significant depolymerization of the cellulosic materials. Methods of treating textiles that include irradiating the textiles are also provided.

The present invention relates to a polymer fiber, in particular a polyethylene polymer fiber obtainable by melt-spinning of a polyethylene polymer, the use of the fiber and a process for the manufacture of the fiber. Further, the present invention relates to a heat sealable filter paper comprising said polymer fiber.