Polypropylene fibers, production

In 1970, an acid-dyeable polypropylene fiber was described [158]. It was claimed that this fiber could be dyed like nylon and could produce one-batch union shades in blends with cotton and acrylics. The dye site in this fiber was present as a microfilament dispersed within the polypropylene. These microfibers extended to the surface of the fiber and water was readily absorbed in order that acid dyes could penetrate at a reasonable rate to react with the basic dye sites. Acid-dyeable polypropylene fiber products have been available from Phillips [159] and, from Polyolefin Fibres Engineering (PFE) Ltd. [160]. PFE has also introduced a bicomponent fiber readily dyeable with disperse dyestuffs [161]. 

In summary, there is an impressive amount of research effort on various polypropylene fiber products. The developments of fine-denier spinning, dyeability modification, high fiber strength and modulus, and nanocomposites certainly appear inductive to further growth in market shares and value-in-use for propylene fibers. However, as with other synthetic fibers, the manufacturing process yield and cost, particularly spinning continuity, must not be adversely impacted by any new technology to be commercialized. This is clearly the key to the future success of polypropylene fibers. 

Physical Properties. Table 1 (2) shows that olefin fibers differ from other synthetic fibers in two important respects (/) olefin fibers have very low moisture absorption and thus excellent stain resistance and almost equal wet and dry properties, and (2) the low density of olefin fibers allows a much lighter weight product at a specified size or coverage. Thus one kilogram of polypropylene fiber can produce a fabric, carpet, etc, with much more fiber per unit area than a kilogram of most other fibers. 

The pigments are used primarily in plastics, including polypropylene fibers, because of very good bleed resistance, heat stabiUty, and lightfastness. The reds also find use in printing inks, primarily for high quaUty products. 

Another use of 4-/ f2 octylphenol is ia the productioa of uv stabilizers. 4-/ f2 -Octylpheaol reacts with sulfur dichloride to yield the thio-hisphenol derivative, which thea reacts with nickel acetate to form 2,2 -thiobis(4-/ f2 octylphenolate)-A/-butylamiQe nickel [14516-71 -3]. This type of stabilizer is widely used in the production of outdoor carpeting based on polypropylene fibers. Nickel compounds give a green discoloration which limits their apphcatioas. A second class of uv stabilizers based on the benzotriazole stmcture. 2-(2 -hydroxy-5 -/ f2 octylphenyl)benzotriazole [3147-75-9] is produced from 4-/ i -octylphenol (55). 

Improvements in melt spinning techniques and film filament processes have made polypropylene accessible for fiber production. Low-cost fibers made from polypropylene are replacing those made from sisal and jute. 

Polypropylene fibers represent a small percent of the total polypropylene production. (Most polypropylene is used as a thermoplastic.) The fibers are usually manufactured from isotactic polypropylene. 

The total 1997 U.S. production of polyolefin fibers, including polypropylene fibers, was approximately 2.5 billion pounds. 

Several manufacturers introduced products amenable for this solid-supported LLE and for supported liquid extraction (SLE). The most common support material is high-purity diatomaceous earth. Table 1.8 lists some commercial products and their suppliers. The most widely investigated membrane-based format is the supported liquid membrane (SLM) on a polymeric (usually polypropylene) porous hollow fiber. The tubular polypropylene fiber (short length, 5 to 10 cm) is dipped into an organic solvent such as nitrophenyl octylether or 1-octanol so that the liquid diffuses into the pores on the fiber wall. This liquid serves as the extraction solvent when the coated fiber is dipped... 

Polypropylene is also used extensively in fiber form in textile applications. One third of polypropylene s production in the United States is used as fiber and the worldwide use of fiber polypropylene was approximately 2.5 million tons in 2005. Major uses of fiber polyethylene are carpeting, upholstery, paper and packaging, construction fabric liners, diapers, and rope. 

A perfluoroacrylate monomer was flash evaporated at 100 millitorr and exposed to polypropylene fibers pretreated in a plasma field within one second while the fabric was traveling at 50 m/min. The condensed monomer layer was then cured in-line by electron beam radiation within 100 milliseconds resulting in a 0.1 pm perfluoroacrylate coating on the material surface. The product had an adequate repellency for both water and oil and a surface energy of 27 dyne/cm. 

Is a low viscosity product that provides excellent lubricity for nylon, polyester and polypropylene fibers. 

Some Effects of Production Conditions on the Photosensitivity of Polypropylene Fibers... 

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