579results about "Monocomponent polypropylene artificial filament" patented technology

Unique copolymers comprising propylene, ethylene and / or one or more unsaturated comonomers are characterized as having: at least one, preferably more than one, of the following properties: (i) 13C NMR peaks corresponding to a regio-error at about 14.6 and about 15.7 ppm, the peaks of about equal intensity, (ii) a B-value greater than about 1.4 when the comonomer content of the copolymer is at least about 3 wt %, (iii) a skewness index, Six, greater than about −1.20, (iv) a DSC curve with a Tme that remains essentially the same and a Tmax that decreases as the amount of comonomer in the copolymer is increased, and (v) an X-ray diffraction pattern that reports more gamma-form crystals than a comparable copolymer prepared with a Ziegler-Natta catalyst. These polypropylene polymers are made using a nonmetallocene, metal-centered, heteroaryl ligand catalyst. These polymers can be blended with other polymers, and are useful in the manufacture of films, sheets, foams, fibers and molded articles.

An implantable structure, method for making the structure and method for using the structure, where the structure includes a combination of non-absorbable and absorbable components, and the implantable structure has a randomly uniform array of materials. The resulting implantable structure provides improved tissue ingrowth and flexibility after implantation and after absorption of the absorbable materials.

Films with excellent machine direction (MD) tear properties comprise at least one layer made from a polymer comprising:(A) at least 50 weight percent (wt %) propylene; and(B) at least 5 wt % ethylene and / or one or more unsaturated comonomers.Representative of component (B) unsatuarated comonomers are the C4-20 α-olefins, C4-20 dienes, styrenic compounds, and the like. Preferably, the film has at least one of a (i) haze value of less than about 10, (ii) 45 degree gloss of greater than about 65, and (iii) dart value of greater than about 100 g / mil. In one preferred embodiment, the layer comprises a compolymer characterized as having at least one of the following properties: (i) 13C NMR peaks corresponding to a regio-error at about 14.6 and about 15.7 ppm, the peaks of about equal intensity, (ii) a B-value greater than about 1.4 when the comonomer content, i.e., the units derived from ethylene and / or the unsaturated comonomer(s), of the copolymer is at least about 3 wt %, (iii) a skewness index, Six, greater than about −1.20, (iv) a DSC curve with a Tme that remains essentially the same and a Tmax that decreases as the amount of comonomer, i.e., the units derived from ethylene and / or the unsaturated comonomer(s), in the copolymer is increased, and (v) an X-ray diffraction pattern that reports more gamma-form crystals than a comparable copolymer prepared with a Ziegler-Natta (Z-N) catalyst.

Unique thermoplastic monofilament fibers and yarns that exhibit heretofore unattained physical properties are provided. Such fibers are basically manufactured through the extrusion of thermoplastic resins that include a certain class of nucleating agent therein, and are able to be drawn at high ratios with such nucleating agents present that the tenacity and modulus strength are much higher than any other previously produced thermoplastic fibers, particularly those that also simultaneously exhibit extremely low shrinkage rates. Thus, such fibers require the presence of certain compounds that quickly and effectively provide rigidity to the target thermoplastic (for example, polypropylene), particularly after heat-setting. Generally, these compounds include any structure that nucleates polymer crystals within the target thermoplastic after exposure to sufficient heat to melt the initial pelletized polymer and allowing such an oriented polymer to cool. The compounds must nucleate polymer crystals at a higher temperature than the target thermoplastic without the nucleating agent during cooling. In such a manner, the "rigidifying" nucleator compounds provide nucleation sites for thermoplastic crystal growth. The preferred "rigidifying" compounds include dibenzylidene sorbitol based compounds, as well as less preferred compounds, such as [2.2.1]heptane-bicyclodicarboxylic acid, otherwise known as HPN-68, sodium benzoate, certain sodium and lithium phosphate salts [such as sodium 2,2'-methylene-bis-(4,6-di-tert-butylphenyl)phosphate, otherwise known as NA-11]. Specific methods of manufacture of such inventive thermoplastic fibers, as well as fabric articles made therefrom, are also encompassed within this invention.

The present invention provides a nanoporous fiber being substantially free from coarse pores and having homogeneously dispersed nanopores, unlike conventional porous fibers. A porous fiber has pores each having a diameter of 100 nm or less, in which the area ratio of pores each having a diameter of 200 nm or more to the total cross section of the fiber is 1.5% or less, and the pores are unconnected pores, or a porous fiber has pores each having a diameter of 100 nm or less, in which the area ratio of pores each having a diameter of 200 nm or more to the total cross section of the fiber is 1.5% or less, the pores are connected pores, and the fiber has a strength of 1.0 cN / dtex or more.

A porous monocomponent nonwoven web contains a bimodal mass fraction / fiber size mixture of intermingled continuous microfibers and larger size fibers of the same polymeric composition. There are at least five times as many microfibers as larger size fibers, and a histogram of the mass fraction of fibers vs. fiber size exhibits a larger size fiber mode greater than 10 μm. The web may be made by flowing fiber-forming material through a die cavity having larger size orifices and at least five times as many smaller size orifices to form filaments, attenuating the filaments into fibers and collecting the attenuated fibers to form the nonwoven web. The web is especially well suited to the manufacture of self-supporting three dimensional articles such as molded cup-shaped respirators and pleated air filters.

A method for producing hydrophobic polyolefin-containing fibers or filaments, in particular cardable staple fibers, using spin finishes applied after spinning and stretching, that comprise at least one water-insoluble ester of a mono-, di-, tri- or tetrahydric alcohol with a molecular weight not exceeding 500 and a branched or straight chain fatty acid with between 12 and 30 carbon atoms, e.g. a water-insoluble ester of ethylene or propylene glycol, glycerol, neopentyl glycol, trimethylolethane or trimethylolpropane and at least one saturated or unsaturated fatty acid residue having 12-24 carbons atoms, an anionic or nonionic antistatic agent preferably being applied after crimping; fibers produced by the method; and nonwovens produced from such fibers.

The invention relates to a nanometer bamboo charcoal antibacterial fiber and a method for producing the same, in particular to a melt-spinning method for producing the nanometer bamboo charcoal antibacterial fiber. The nanometer bamboo charcoal antibacterial fiber consists of nanometer bamboo charcoal, nanometer silver and a carrier slice, wherein the carrier slice is one of terylene, polypropylene fiber or chinlon. An antimicrobial master batch is prepared first and is mixed with the carrier slice according to certain proportion, and then the mixture is used for preparing the required nanometer bamboo charcoal antibacterial fiber through the melt-spinning method. The nanometer bamboo charcoal antibacterial fiber has the advantages that the bamboo charcoal is a renewable resource which is rich, can be produced through adjusting part of the process conditions by using the prior equipment, and passes test and detection with the antibacterial rate of more than 98 percent; and the nanometer bamboo charcoal antibacterial fiber is not only applied in the aspect of dress, but also widely applied to transportation, environmental protection, medical treatment and other industries.

Improved polypropylene fibers exhibiting greatly reduced heat- and moisture-shrink problems and including certain compounds that quickly and effectively provide rigidity to the target polypropylene fiber after heat-setting are disclosed herein. In such a manner, the "rigidifying" compounds provide nucleation sites for polypropylene crystal growth. After drawing the nucleated composition into fiber form, the fiber is then exposed to sufficient heat to grow the crystalline network, thus holding the fiber in a desired position. The preferred "rigidifying" compounds include dibenzylidene sorbitol based compounds, as well as less preferred compounds, such as sodium beuzoate, certain sodium and lithium phosphate salts (such as sodium 2,2'-methylene-bis-(4,6-di-tert-butylphenyl)phosphate, otherwise known as NA-11).

Substantially isotaclic propylene interpolyraets comprise (A) at least 60 weight percent (wt %) units derived from propylene, and (B) between greater than zero and 40 wt % units derived from ethylene, the propylene interpolyrner further characterized by at least one of the following properties: (1) a ratio of less than 1 measured at interpolyraer number average molecular weight (Mn), (2) a relative compositional drift of less than 50%, arid (3) propylene chain segments having a chain isotacticity triad index of at least 70 mole percent.

The present invention relates to fibers, in particular to as-spun fibers, having an improved bonding performance. In particular, the present invention relates to as-spun fibers comprising a metallocene random copolymer of propylene and one or more comonomers. The present invention further relates to nonwovens comprising such fibers and to a process for producing such fibers and nonwovens. The fibers and nonwovens of the present invention are characterized by a wider bonding window as the prior art fibers and nonwovens.

Synthetic staple fibers having good air opening property and useful for producing an air-laid nonwoven fabric having excellent quality, have a fiber length of 0.1 to 45 mm and a cross-sectional profile having 1 to 30 concavities, in which cross-sectional profile the ratio D / L, of a largest depth D of each concavity to a largest width L of the opening of the concavity, is in the range of from 0.1 to 0.5.

Polymer blends that exhibit good impact resistance comprise a crystalline polypropylene matrix and a partly crystalline copolymer impact modifier with a molecular weight lower than that of the matrix polymer. The matrix polymer can comprise any crystalline propylene homo- or copolymer. The impact modifying copolymers are characterized as comprising at least about 60 weight percent (wt %) of units derived from propylene and, in certain embodiments, as having at least one, preferably two or more, of the following properties: (i) 13C NMR peaks corresponding to a regio-error at about 14.6 and about 15.7 ppm, the peaks of about equal intensity, (ii) a B-value greater than about 1.4 when the comonomer content of the copolymer is at least about 3 wt %, (iii) a skewness index, Six, greater than about −1.20, (iv) a DSC curve with a Tme that remains essentially the same and a Tmax that decreases as the amount of comonomer in the copolymer is increased, and (v) an X-ray diffraction pattern that reports more gamma-form crystals than a comparable copolymer prepared with a Ziegler-Natta (Z-N) catalyst.

An auxetic material, which has a negative Poisson ratio so that it has the property of expanding or contracting transversely to a direction in which it is extended or compressed, is made in filamentary or fibrous form. A suitable process involves cohering and extruding heated polymer powder so that the cohesion and extrusion is effected with spinning to produce auxetic filaments. Typically the powder is heated to a temperature sufficient to allow some degree of surface melting yet not high enough to enable bulk melting.

The present invention is directed to the combined use of first and second fatty acid amides to improve the softness of a thermoplastic polymer construct. A combination of fatty acid amides is provided in the blend ratio of about 10 to 90 percent by weight of a first fatty acid amide and 90 to 10 percent by weight of a second fatty acid amide. The first and second fatty acid amides are compounded into a thermoplastic polymer carrier resin and, preferentially, produced as concentrate pellets containing 0.5 to 75 percent by weight total fatty acid amide loading. The concentrate pellets are introduced into a thermoplastic polymer base, to form a thermoplastic resin, at a letdown level in the range of about 1 to 15 percent, with the range of 2 to 10 percent being preferred, and the range of 3 to 6 percent being most preferred.