Polypropylene fibers properties

The dyeing of polypropylene fibers, being an item of research for decades, is successfully accomplished with partially stearate-modified hyperbranched polyesteramides. The long alkyl chains ensure compatibility with the polypropylene matrix. The mixing-in of hyperbranched polyesteramides via extrusion affected neither the melt spinning process nor the final polypropylene fiber properties. The modified fibers are dyeable under standard conditions as are, e.g., polyesters or cotton. They can even be used for printing for example a picture pattern on a polypropylene carpet. 

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. 

Mahlberg, R., Paajanen, L., Nurmi, A., Kivisto, A., Koskela, K. and Rowell, R.M. (2001). Effect of chemical modification of wood on the mechanical and adhesion properties of wood fiber/polypropylene fiber and polypropylene/veneer composites. Holz als Roh- und Werkstoff, 59(5), 319-326. 

A.R. Horrocks, B.K. Kandola, G. Smart, S. Zhang, and R. Hull, Polypropylene fibers containing dispersed clays having improved fire performance. Part 1 Effect on nanoclays on processing parameters and fibres properties, J. Appl. Polym. Sci., 2007, 106 1707-1717. 

Effect of Clay and Compatibilizer Type and Levels on Physical and Flammability Properties of Polypropylene Fibers/Fabrics... 

Auxiliary Materials. Glass fibers, polypropylene fibers and simUar fibers may sometimes be used as reinforcing materials for phenolic foams. Mechanical properties and heat resistance are improved by reinforcing phenolic foams with these fibers. 

Pezelj E, Cunko R and Andrassy M, The influence of repeated maintenance treatments on chemical and thermal properties of polypropylene fibers 78th World Conference of the Textile Institute, 5th Textile Symposium ofSEVE and SEPVE, volume HI, 395-400, Thessaloniki, Greece, 1997. 

In some cases, this orientation may be difficult to predict. Thus, a study of the adsorption of a series of w-alkyl sulfates and POE nonylphenols onto isotactic polypropylene fiber and of the washing properties of the same surfactants for the... 

Benzothiazines have been used in industry as dyes and as antioxidants of rubber and natural elastomers. They have been used widely to prepare azodye compounds with specific properties, such as water insolubility, which is useful in the dyeing of polypropylene fibers, and increased stability to gas fading.72,73 Several reports are concerned with the antioxidant properties of benzothiazines,74-77 and their use as color photography developers.78... 

Through plasma treatment, grafing of monomers can also take place on the polymer surface. For example, monomers, e.g., tetrafluoroethylene or hexafluoroethane, can be grafted onto wool or polypropylene fibers ( ). This type of grafting can improve such tribological properties as low friction. 

For providing electrical paper sheets [reduce the dielectric loss and increase the dielectric properties), literature attempts include the modification of paper substrate by oxidation [35], impregnation of cellulose paper with insulating oils [36], and replacing the cellulose fibers by some synthetic materials that exhibit better dielectric properties than cellulose, e.g., polypropylene fibers and other synthetic fibers [37, 38], or by treating with ferric chloride [39]. 

It has been demonstrated in recent years that the nanotechnology can be applied to textiles to enhance various properties, especially in functional coatings, such as fabric softness, durability and breathability, water repellency, fire retardency, antimicrobial properties, anticrease properties, UV protection, self-cleaning properties and like in fiber, yarn and fabrics [131, 134-136]. Undyable polypropylene fiber can be made dyeable by... 

The melting point of polypropylene is an advantage in many new nonwoven products. Polypropylene fibers can be melted sufficiently to bond to one another without destroying fiber properties. Nonwoven fabrics made from polypropylene can, therefore, be fusion-bonded. 

The use of polypropylene fibers will grow depending on the ability of the textile industry to take advantage of properties that can be built into polypropylene. Some of these properties, such as toughness, low density, chemical stability, etc., are inherent to all polypropylene products. Others, like color stability and UV and thermal stability, are built into the product by additives. Still others, such as improved uniformity due to low-temperature extrusion of modified polymers, open new areas of use. The future growth of polypropylene in textiles depends on the ability of the suppliers and users to take advantage of all the properties to make unique products from polypropylene. 

In recent years, the quality of polypropylene fiber has been improved to enhance such properties as light weight, moldability, light stability, coloration, recovery feasibility, flame resistance, and antistatic propensity. It is increasingly used for automotive interior furnishing and parts. 

There have been numerous formulations of the metalloeene catalysts in the last 20 years. Table 3.4 presents a few examples of metallocene catalyst systems of interest (see all preceding references) [58-66]. It can be seen that earlier efforts were focused on catalyst efficiency and polymer stereospecificity. More recently, some interests seemed to have turned to syndiotactic polypropylene for various polymer and fiber properties. 

An important factor to consider on the blending of polymeric materials is that most polymers are incompatible with polypropylene on the molecular scale. This might cause many problems, such as macro-phase separation during blending, low interface adhesion, low tensile transfer rate, and low physical properties, which may be even lower than the unmodified polymer. To sustain good fiber properties, controlling the phase structure and interface adhesion is a necessity. 

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