Polypropylene fibre

In 1956, polyethylene fibres were prepared and later on polypropylene fibres were prepared. Fibres have been made from polytetrafloroethylene for special uses. 

Polypropylene fibres are used to reinforce polypropylene matrices leading to a selfreinforcing polymer. 

The first industrial development is CURV by BP, a highly-stretched polypropylene fibre reinforced polypropylene delivered in sheets of 0.3 mm to 3 mm thickness. 

Fig. 5. Raman spectra of an isotactic polypropylene fibre.------- electric vector...

We will now consider three cases where satisfactory peak resolution was much more difficult to achieve. Case (a), a specimen of PET fibre used for texturising, having poorly defined crystalline peaks and possibly an additional peak due to an intermediate phase (11) case (b), a specimen from a range of PET fibres with different shrinkages (.12.), again an additional intermediate phase peak was a possibility case (c), cold drawn polypropylene fibres (13). an additional paracrystalline peak was most likely here. 

Buszard, D. L. Inherently flame retadant polypropylene fibres. In Proceedings of Conference Textile Flammability Current and Future Issues, March 30-31, Textile Institute, Manchester, 1999. 

Zhang, S. and Horrocks, A.R. 2003. A review of flame retardant polypropylene fibres. Prog. Polym. Sci. 28 1517-1538. 

The entire installation is finished with a carpet of synthetic grass, which comprises usually a woven polypropylene lattice in which tufts of green polypropylene fibre or filament are fixed. The lattice is sealed on the under-side with a bonded film—which keeps the tufts in place and may be made from polyethylene, polyurethane, rubber latex, or vinyl plastisol. 

There is interest in trace metal levels in both natural and synthetic fibres and fabrics but perhaps most interest is in synthetic fibres as these may contain residues of catalysts, treatments or stabilising agents. Reviews have been published of trace-metal analysis of rayon, polyamide, polyester and polypropylene fibres [178] and of cotton fabrics, especially for flame... 

Monofilament polypropylene fibres were prepared by direct extrusion having a rectangular cross section of 0.5 x 1.3 mm, a length of 40 mm, a specific gravity of 0.91, a tensile strength of 120 MPa, and an elongation at break of 14%. The fibers were placed under 18% humidity at ambient temperature air and then treated with 20% F2 and 80% N2 at apressure of 45 kPa at 38°C for 2.5 hours. Thereafter the reaction vessel was evacuated, and the product was isolated. 

Polypropylene fibres can be flame retarded with bromine- and phosphorous-containing additives to the polymer melt. However, very high add-ons are necessary and fibre properties are adversely affected. When polypropylene is used in carpets, flame retardancy can be achieved by incorporating halogen-containing compounds and antimony trioxide into the latex backing. ... 

Strong-base ion-exchange fibrous materials (SBF) were tested as sorbents for purification of air from acid impurities exemplified by S02- The SBF exchangers were prepared by amination with the trimethylamine of chloromethylated polystyrene grafted on polypropylene fibres. 

Polyethylene and polypropylene fibres are both used as fibre-forming for textile purposes. They are widely used in industrial fabrics. These two fibres can be bonded into non-woven fabric form and used as the base for tufted carpeting. Olefin fibres are relatively low in cost, but both the fibres have low melting points, low glass-transition temperatures and poor dyeability. 

The filaments of polypropylene fibre are produced from propylene using special catalysts. The polymerisation process involved is addition, as the double bond is broken in the propylene molecule, the monomer or single molecules join or add together. The filaments are produced by the melt-spinning process in a similar manner to polyester. The repeat unit of polypropylene is... 

The total content of oils, fats and waxes on fabrics can be extracted with 1,1,1-trichloroethane using the Soxhlet extractor. By comparing the fabric weight before and after extraction, the weight percentage of oils, fats and waxes can be easily calculated. It was reported that supercritical CO can be used instead of the toxic organic solvent to extract the commercial finishes from polyester, nylon and polypropylene fibres. ... 

Photostabilization processes have not received much attention in the last year other than a multitude of review and specialist industrial articles. These include stabilization of polypropylene fibres, new stabilizer developments, sorting of stabilizers for polyethylene, trends in UV absorbers, hindered piperidines (hindered amine stabilizers (HAS)) for polyacrylics and urethanes, new stabilizers for polyolefins, enhanced service life applications, stabilizer mas-terbatches for polyester, stabilizers for UV cured acrylic overcoats for PVC, ° stabilization of clearcoats and various commercial packages. ... 

Adsorption Cellulose, chitine (chitosan), nylon, polypropylene fibres, polymer nets and membranes, wood, lignine, ion-exchange resins, polyurethane foam, polyacrylamide (Porous) glass, clay,bentonite, zeolithes, ceramics, meso-porous silica, metal oxides (Fe, Ti, Mg), metal phosphates, mineral powder... 

Vahdat, A., Bahrami, H., Ansari, N., and F. Ziaie. 2007. Radiation grafting of styrene onto polypropylene fibres by a 10 MeV electron beam. Radiation Physics and Chemistry 76 787-793. 

Fibres of the above types (3 mm in length) and polypropylene fibres are introduced into the paste with the aim to provide mechanical stability to the structure of NAM. Because of the poor adhesion between lead and fibre particles, the role of mechanical strengthener of the NAM structure is not always very pronounced. Beyond any douht, however, fibre additions reduce substantially the waste during the pasting process and throughout the technological process of negative plate manufacture, which provides very important economical effect. 

The other paste components mentioned in the subtitle of this section have analogous effects. Moreover, they promote formation of macropores in NAM, thus facilitating the movement of ions into the plate interior. All these functions of the additives stabilizing mechanically the structure of NAM make them an indispensable component of the paste formulations for negative battery plates. Usually, polypropylene fibres with a length of 3 mm are introduced in amount within the range 0.075—0.08 wt% versus the leady oxide used for paste preparation. 

For semi-crystalline polymers, the average orientation function 2 for the crystal c axes can be calculated from X-ray diffraction measurements (Chapter 3). Figure 8.15 shows how 2 increases linearly with the draw ratio, for polypropylene fibres and films, while the spherulitic microstructure survives. At 2 = 0.9, where the spherulites are destroyed and replaced by a microfibrillar structure, there is an increase in the slope of the 2 versus true strain relationship. It is impossible to achieve perfect c axis orientation... 

Figure 8.1 5 The crystal orientation of polypropylene fibres and films as a function of the true strain in the deformation process draw temperatures ( ) 135 °C, (a) I 10 °C. The prediction of the pseudo-affine model is shown as a dashed line (from Samuels RJ. Structured Polymer Properties, Wiley, 1974).

For polyolefins used under aggressive conditions (e.g. polypropylene fibres subject to dry-cleaning or detergent action) solvent-resistant TMP systems have been developed by covalent chemical attachment of UV stabilisers to the polymer. Two synthetic routes have been developed to do this. The first involves the modification of the polymer e.g. polypropylene) by copolymerisation with maleic anhydride to give an anhydride group in the polymer chain. This can be subsequently reacted with an alcohol or amine group in the light absorber ... 

P. Kalifa et al. High-temperature behavior of HPC with polypropylene fibres from spalling to microstructure. Cement and Concrete Research, Vol.31, (2001), pp. 1487-1499... 

Similar measurements have been made by Samuels - on as-spun and drawn polypropylene fibres and they are correlated with crystalline orientation functions, light and low angle X-ray scattering studies. 

Finally, there is the very interesting result that in oriented linear polyethylene and polypropylene fibres, a three component NMR spectra has been observed, first by Hyndman and Origlio. " In addition to the broad crystalline component and the narrow amorphous component, there was a third component of intermediate line width, which was attributed to strained amorphous material. This intermediate component was much reduced in intensity on annealing and consequent shrinkage of the fibre, which is consistent with the proposed interpretation. A three-... 

Wadas, W. Jablonska-Ceglarek, R. Rosa, R. (2001). A posssibility of increasing the yield of young potato tubers by using a polypropylene fibre covers. Electronic Journal of Polish Agricultural Universities, Horticulture, Vol. 4, Issue 2, ISSN 1505-0297, Available online ... 

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