Monofilament fibers

In all cases the anisotropic polymerization mixtures (10% by weight) could be used directly in the formation of dry-jet wet-spun fibers. Monofilament fibers were obtained by coagulation in water, tension dried at 150 °C and heat treated at 500-600 °C with a 30s residence time. The best fibers were obtained from the high molecular weight PBZT polymer (VII) which exhibited modulus values that ranged between 172 GPa and 207 GPa and tenacity values up to 2.4 GPa. Unfortunately, the compressive property as measured by the tensile recoil test was only 380 MPa, showing only a slight improvement over PBZT. 

Early in the manufacture of PP, a concept was developed for dry spinning directly from the solution obtained in the polymerization operation. Had it been feasible, it would have been the realization of a chemical engineer s dream the gaseous olefin fed into one end of the equipment, and the packaged fiber, ready for shipment to a textile mill, coming out the other end. But it did not turn out that way, and today melt spinning is the accepted technique for the production of staple fibers, monofilament, and multifilament yams. To this usual method have been added the fibrillation and the slit film procedures for producing yams. 

For fiber formation from a polymer, it is necessary for the polymer to either melt at an elevated temperature or dissolve in a solvent. The first commercially produced PVC fiber (monofilament) was made by a method of melt-spinning [144]. However, melt-spinning of PVC is not an agreeable process because of its high melting point, its high melt viscosity, and its low thermal stability. 

Uses Thermoplastic resin for inj. molding of precision parts in instrument mechanics and chemical engineering, extruded stock, film, fibers, monofilaments, gears, cams, bearings food pkg. 

The SiC fiber monofilaments consist of a SiC sheath with an outer diameter of 142 j-m surrounding a pyrolitic graphite-coated carbon core with a diameter of 37 jim. On the surface of the SiC fiber contained two layers of carbon-rich surface coating. Each layer is a mixture of amorphous carbon and SiC. 

The type of sample most frequently used (thin films, fibers, monofilaments, etc.) on the Rheovibron will not support a compressive load without buckling. This condition would, of course, distort the negative portion of the sine wave making measurements impossible. To alleviate this situation, the sample must be maintained under sufficient tension to eliminate buckling but insufficient to introduce non-linearity or excessive creep into the experiment. The amount of tension is critical to the measurement. 

Figure 5.7 Tensile strength of carbon fiber monofilaments as function of fiber diameter. Source Reprinted with permission from Fitzer E, PAN-based carbon fibers-present state and trend of the technology from the viewpoint of possibilities and limits to influence and control the fiber properties by the process parameters, Carbon, 27(5), 621-645, 1989. Copyright 1999, Elsevier.

Uniaxial orientation n. An orientation process that stretches the product in only one direction, as in manufacture of staple fiber, monofilaments, and melt-cast film. 

Recommended for products fibers, monofilaments, flat yarn, ribbons, net, films ... 

Keywords use, application, chemical fiber, polypropylene fiber, monofilament, multifilament, staple fiber, tapes, spunbond, melt blown, split film, textile yarn, knitted fabrics, clothing, nonwoven fabric, home textiles, upholstery, geotextiles, agrotextiles, composites, medical textiles, automotive textiles, bulk continuous filaments (BCF), Eco-textiles, integrated fabric. 

Keywords bulk continuous fibers (BCF), crystallinity, drawing, elasticity, elongation, fiber-forming polymer, fiber monofilament, low oriented yam (LOY), melt blown process, melting, monofilament, multifilament silk, orientation, partially oriented yam (POY), staple fibers, spinning, spunbonded fibers, stmcture, technical fiber, tenacity, textile fiber, texturing. 

Rather than short fibers, monofilaments have length enough to be considered and used as an individual implantable medical device. Used in their most basic form, monofilaments are commonly subjected to tensile and bending stress in order to bring side by side two or more edges of native tissues/organs, whether wounds or sternum closures, for example. 

The manufacture of high quality yarn at high takeup speeds obviously requires high speed winders. The extruder and the lower part of the spinning machine are basically the same as for conventional spinning. New processes have created a variety of new flat fibers (monofilaments, fine denier filaments, noncircular cross section filaments, staple fibers. 

The case is schematically shown in Figure 9.7 where the shaded volume represents the solid cylindrical fiber (monofilament yam). 

Mechanical degradation which leads to formation of free radicals can be achieved in various ways but generally two types of samples are being used in experiment powders of finely ground polymers as discussed above or uniaxially stressed fibers, monofilaments, or strips of films. In samples of the first type all molecular fracture processes are completed before the ESR investigation begins. These samples can primarily be used to obtain information on the nature and absolute number of free radicals present within the degraded polymer. 

Major fields of application of this additive, typically used in a concentration between 0.1 and l.Owt.%, are thick section injection molded, even glass filled and/or pigmented resins, thin section fibers, monofilaments, films, and blow molded articles. Important benefits of Nylostab S-EED are improved thermo-oxidative and UV light stability enhanced output rates due to lowered and constant pressure during processing (see Figure 25), reduced cycle times and lower discoloration, respectively, nonstaining effects. Furthermore, this additive proteas colorants and provides better bleach resistance. 

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