Disclosed herein are polymer elements, e.g. fibers and tapes, produced by a process consisting of a series of hot drawing steps interspersed with periods of quiescent heating and the process for producing the same. The polymer elements may comprise polyolefin materials such as ultra-high molecular weight polyethylene. The polymer elements may be used to form fabrics or composite materials by themselves or in combination with other polymeric materials.

Aspects herein relate to biocompatible polyisobutylene-fiber composite materials and related methods. In one aspect a biocompatible composite material is included. The biocompatible composite material can include a network of fibers comprising one or more polymers to form a substrate and a continuous polyisobutylene matrix that is non-porous and completely surrounds the electrospun fibers. Other aspects are included herein.

A cusp die for producing melt-blown non-woven fabric is provided, defining a sagittal plane, a main extension direction on the sagittal plane, a first flank and a second flank mutually bounded by the sagittal plane and including an ejection portion extending along the main extension direction and designed to convey, in use, polymeric fluid towards an external air blade, at least one extrusion pipe configured to convey the polymeric fluid towards the ejection portion, a plurality of holes arranged in the ejection portion, placed in fluidic through connection with the extrusion pipe and communicating with the outside, wherein the holes are arranged along at least one first row and a second row that are distinct and arranged respectively at the first flank and the second flank.

A polyester with ultra-high flowability and good stability over time is provided. The polyester can be polybutylene terephthalate (PBT) or another aliphatic polyester, whose intrinsic viscosity (IV) is less than 0.6 dL/g and a carboxylic end group (CEG) content is 15 meq/kg or less, and characterized by having a melt volume rate (MVR) of greater than 400 cm.sup.3/10 min at 250° C. A resin composition of this polyester is provided, which can be meltblown into microfibers of a uniform diameter and a concentrated diameter distribution, forming a fabric with a uniform small pore size.

An apparatus for making spunbond from continuous thermoplastic filaments has a spinneret for spinning the continuous filaments and advancing them in a filament-travel direction, a cooler for cooling the filaments, a stretcher for stretching the filaments, a depositing device including a foraminous belt extending in a machine direction transverse to the filament-travel direction for deposition of the filaments as a nonwoven web and conveyance away from the stretcher, a diffusor between the stretcher and the foraminous belt so that filaments and primary air from the stretcher enter into the diffusor, and a suction device for extracting air through the foraminous belt at an unobstructed extraction region underneath the diffusor outlet and having a width b in a machine direction that is greater than a width B of the diffusor outlet. The diffusor forms upstream and downstream secondary air-inlet gaps at opposite ends through which secondary air is aspirated into the diffusor.

An apparatus for making spunbond from continuous thermoplastic filaments has a spinneret for spinning the continuous filaments and advancing them in a filament-travel direction, a cooler for cooling the filaments, a stretcher for stretching the filaments, a depositing device including a foraminous belt extending in a machine direction transverse to the filament-travel direction for deposition of the filaments as a nonwoven web and conveyance away from the stretcher, a diffusor between the stretcher and the foraminous belt so that filaments and primary air from the stretcher enter into the diffusor, and a suction device for extracting air through the foraminous belt at an unobstructed extraction region underneath the diffusor outlet and having a width b in a machine direction that is greater than a width B of the diffusor outlet. The diffusor forms upstream and downstream secondary air-inlet gaps at opposite ends through which secondary air is aspirated into the diffusor.

Described are very high molecular weight (e.g., over 2 million, such as 3-20 million g/mol) starch-based materials, and formulations including such, which can be spun in spunbond, melt blown, yarn, or similar processes. Even with such very high molecular weights, the formulations can be processed at commercial line speeds, with spinneret shear viscosities of 1000 sec.sup.−1, without onset of melt flow instability. The starch-based material can be blended with one or more thermoplastic materials having higher melt flow index value(s), which serve as a diluent and plasticizer, allowing the very viscous starch-based component to be spun under such conditions. The particular melt flow index characteristics of the thermoplastic diluent material can be selected based on what type of process is being used (e.g., spunbond, melt blown, yarn, etc.). The starch-based material may exhibit high shear sensitivity, strain hardening behavior, and/or very high critical shear stress (e.g., at least 125 kPa).

A fiber-wrapped smokeless tobacco product includes smokeless tobacco and a plurality of polymeric fibers surrounding the smokeless tobacco. The polymeric fibers can have a basis weight of 5 gsm or less and a diameter of less than 100 microns. In some cases, the polymeric fibers are melt-blown polymeric fibers. In some cases, the polymeric fibers are centrifugal force spun polymeric fibers. A method of preparing a fiber-wrapped smokeless tobacco product includes melt-blowing or centrifugal force spinning a plurality of polymeric fibers to create an polymer deposition zone and passing a body comprising smokeless tobacco through the polymer deposition zone. In some cases, an electrostatic charge can be applied to the plurality of polymeric fibers, the body, or a combination thereof. In some cases, a spin is applied to the body when passing through the polymer deposition zone.

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.