Electrospinning is a rapidly growing polymer processing technology as it provides a viable and simple method to create ultra-fine continuous fibers. This paper presents an in-depth review of the mechanical properties of electrospun fibers and particularly focuses on methodologies to generate high strength and high modulus nanofibers. As such, it aims to provide some guidance to future research activities in the area of high performance electrospun fibers.

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High Strength and High Modulus Electrospun Nanofibers

High density para-aramid papers comprising 5 to 25 percent, by weight, binder and an amount of para-aramid fibers selected from the group consisting of para-aramid pulp, para-aramid floc and mixtures thereof, compacted to provide a volume percent para-aramid fiber of at least 53 minus 0.13 times the volume percent floc in the paper are useful in the preparation of circuit board substrates having a low coefficient of thermal expansion.

High density para-aramid papers

Arrangement for producing a three-dimensional product, which arrangement comprises a work table on which said three-dimensional product is to be built up, a powder dispenser which is arranged so as to distribute a thin layer of powder on the work table for forming a powder bed, a radiation gun for delivering energy to the powder, fusing together of the powder then taking place, means for guiding the beam emitted by the radiation gun over said powder bed for forming a cross section of said three-dimensional product by fusing together parts of said powder bed, and a control computer in which information about successive cross sections of the three-dimensional product is stored, which cross sections build up the three-dimensional product, where the control computer is intended to control said means for guiding the radiation gun over the powder bed according to an operating scheme forming a cross section of said three-dimensional body, said three-dimensional product being formed by successive fusing together of successively formed cross sections from by the powder dispenser, and method for producing a three-dimensional product using such an arrangement.

Arrangement and method for production of a three dimensional object

Recent developments in graphene oxide fibre (GO) processing include exciting demonstrations of hand woven textile structures. However, it is uncertain whether the fibres produced can meet the processing requirements of conventional textile manufacturing. This work reports for the first time the production of highly flexible and tough GO fibres that can be knitted using textile machinery. The GO fibres are made by using a dry-jet wet-spinning method, which allows drawing of the spinning solution (the GO dispersion) in several stages of the fibre spinning process. The coagulation composition and spinning conditions are evaluated in detail, which led to the production of densely packed fibres with near-circular cross-sections and highly ordered GO domains. The results are knittable GO fibres with Young's modulus of ~7.9 GPa, tensile strength of ~135.8 MPa, breaking strain of ~5.9%, and toughness of ~5.7 MJ m(-3). The combination of suitable spinning method, coagulation composition, and spinning conditions led to GO fibres with remarkable toughness; the key factor in their successful knitting. This work highlights important progress in realising the full potential of GO fibres as a new class of textile.

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Towards the Knittability of Graphene Oxide Fibres.

This invention relates to a blend of fibers for use in protective clothing, a lightweight fabric made from such blend, protective articles made from the blend or fabric, and methods for making the fabric. The protective fabrics and articles of this invention have the unique combination of being comfortable, being highly effective against electrical arcs and flash fire hazards and having a pleasing appearance. Specifically, these fabrics can be processed to give the look and feel similar to conventional clothing fabrics such as denim fabrics.

Lightweight protective apparel

Fibers and films of extremely high strength, i.e. at least about 18 gpd. consist essentially of certain polyamides. These products have filament and film elongations of at least 3.5% and possess a novel crystalline structure with crystalline regions having a primary apparent crystallite size of less than 52 Angstrom units.

High strength polyamide fibers and films

High strength, high modulus fibers having a density of at least 1.4o g./cm.3 and consisting essentially of poly(p-phenylene terephthalamide) of inherent viscosity of at least 4.0 are provided. These fibers have a lateral birefringence of at least 0.022, a novel crystalline structure with crystalline regions having an apparent crystallite size of greater than 58 Angstrom units (A), and an orientation angle no greater than 13* with the proviso that the ratio of the apparent crystallite size to the orientation angle (degrees) is at least 6A/degree.

Herbert Blades

Papers

High strength polyamide fibers and films

High modulus, high tenacity poly(p-phenylene terephthalamide) fiber