CS275806B6 - Polypropylene fiber configuration - Google Patents

Abstract

The solution concerns a polypropylene fibrous structure, the fibers of which - monofilaments - consist of a system of combinations of strong shapes disorganizedly distributed in a given cross-section as well as along the monofilament. The invention solves the cumulation of the desired properties of the fibers, which is caused by increasing the specific surface and subsequent chemical and physical activity of the fibers. The essence of the invention is that the fibers consist of a system of combinations of strong shapes, while achieving a synergistic effect different from the additive value of the Specific effects of individual shapes. Polypropylene fibrous structures do not have a circular profile and contain a combination of strong shapes, e.g. Y, C, G, three-anchor, four-anchor, triangle. The invention can be used in industrial applications, both process (filtration, adsorption, separation processes) and physical (thermal and sound insulation).

Description

The invention relates to a polypropylene fibrous structure.

Hitherto known polypropylene fibrous structures are composed of monofilaments (fibrils) which have a transverse geometry in the shape of a circle or an annulus. Fibrous structures with a different transverse geometry from a circular one composed of fibrils of the same cross-section are also known. Such fibrous structures are described in M. Ahmed: Polypropylene Fibers Science and Technology, Elsevier Scientific Publishing Company, Amsterdam, Oxford, New York, 1982 and are known from the 4th International Conference on Polypropylene Textiles and Fibers, no. 19, M. Jambrich: Production of profiled polypropylene fibers by aggreated method, University of Nottingham, 23 - 25 September 1987. Fibrous structures formed from groups of fibrils of the same cross-section different from circular (pat. GB 973 358, JP 63) are also known. 417/77). In these cases, it is an organized grouping of different profiles into groups that have fibril profiles of the same cross section.

A disadvantage of the hitherto known types of polypropylene fibrous structures is that they provide a smooth surface, which results in a lower chemical and physical activity due to the relatively small surface area. Fibrous structures with a different transverse geometry than a circular one, composed of fibrils of the same cross-section or groups of the same cross-section in the fibrils, provide improved properties, but only in a certain parameter. For example, improving the moisture transport is made possible by a profile consisting of two arms that form a right angle (90 *), Y, where the physicochemical activity depends on the properties provided by the individual profile and its effects.

This shortcoming of the prior art is overcome by the invention, the essence of which is that the polypropylene fibrous structure is formed by a heterogeneous mixture of different profiles which are disorganized in a given cross section as well as along the fibrous structure and have a Y-shape, Segner wheel, C, equilateral triangle , triplets and the shape of three symmetrically placed lunar lobes with central protrusions facing the center of symmetry, whereby these shapes achieve a higher bulk and a specific surface area as well as a matt surface. In the case of L shapes, the shape of three moons, the axes of which form an angle of 60 *, G and an angular U, a higher physicochemical activity is achieved, e.g. higher moisture transport, improved feel and higher volume. The Y-shapes, Segner-shaped wheel, equilateral intermittent triangle, the axes of the sides of which are connected to its center, T, C, a symmetrical cross and the shape of three moons, the axes of which form an angle of 60 ', achieve higher resistance to deformation and higher specific volume. For the shapes of the triple anchor, quadrupole, G and the shape of an equilateral intermittent triangle, the axes of the sides of which are connected to its center, a higher separation capacity for non-polar substances is achieved. These combinations mainly achieve an increase in the specific surface area of fibrous structures and an increase in their physicochemical activity as a result of the synergism of a mixture of different profiles forming a planar and spatial structure with a larger surface area of min. by 20% of macropores compared to the macropore size of individual profiles assumed on the basis of additivity (aggregation effect). This synergism is particularly pronounced for shapes that have sharp angles between the arms. At the same time, the effect of the combinations of different shapes, which are characterized by the disorganized arrangement of the different fibril profiles, achieves an accumulation of the desired functional properties, e.g. heat and sound insulation, improved textile feel, etc. An advantage of the invention is that in polypropylene fibrous structures the accumulation of the desired functional properties of these shapes is achieved with a higher than expected effect, which allows their more diverse application due in particular to the accumulation of improved physicochemical properties and physicochemical activity. The method of preparation of some types of polypropylene fibrous structures and the description of their properties is given in the following examples, where the effects of individual combinations of shapes used on the extrusion nozzles shown in the figure appendix are also defined.

CS 275806 B6 '

Example 1

Polypropylene polymer fibers with an IT index of 6 g / 10 min were prepared on a threaded extruder TŠ-16. at a melt temperature on a nozzle of 270 ‘C with a fineness of 170/13 dtex. The fibers are a small mixture of transverse profiles shown in the figure under no. 1 to 6, 14, 22, 23, 27, 28. The elongated fibers had a strength of 2.5 cN / dtex, an elongation of 40%, a duller surface, a higher bulk density and a higher specific surface area of 40 .mu.m compared to fibers with a circular cross-section.

Example 2

By the procedure of Example 1 using nozzles with the holes shown in the figure under no. 7, 8, 10, 15, 29, 30, fibers were produced with a higher moisture transport of about 20% and with an improved feel compared to the additive value of the separately evaluated individual profiles.

Example 3

Mixtures of polypropylene fibers with different transverse geometries were prepared on a thread extruder TŠ-90 at a melt temperature of 270 ° C with a fineness of 15,000/100 dtex. The fibers behind the spinneret were cooled with an aqueous solution, divided to a lambda extension ratio of 2.8, had a strength of 2.4 cN / dtex and a 70% elongation. The transverse profile of the fiber consisted of a combination of shapes according to the figure under no. 7, 8, 15, 19, 25, 26. These fibers were characterized by a higher separation ability by 30% compared to the additive value of separately evaluated profiles. The adsorption capacity of oil from water of 1.2 kg.kg of fiber was achieved as a result of the synergism of the effect of the individual profiles in their combination. These fibers had an increased sound absorption compared to fibers with a circular cross-section of the same fineness by up to 70%.

Example 4

Mixtures of polypropylene fibers with a corner transverse geometry were prepared on a thread extruder TŠ-90 at a melt temperature on a nozzle 280 ° C with a fineness of 15,000/50 dtex. The fibers behind the spinneret were cooled with an aqueous solution, divided to a lambda elongation ratio of 3, had a strength of 2.2 cN / dtex and an 80% elongation. The transverse profile of the fiber (monofilament) was a combination of shapes as shown below δ. 1, 2, 3, 8, 9, 11, 12, 13, 14, 16, 24. These fibers were characterized by a higher resistance to deformation by 35% compared to the additive value calculated from the effect of each individual profile and a higher specific surface area compared to with a fiber of circular cross-section.

Example 5

By the procedure of Example 1 using nozzles with the holes shown in the figure under no. 7, 10, 11, 15, 16, 18, 19, 20, 21, fibers with higher absorption and higher separation effect (separation of oil from the gas phase) were produced min. by 20% compared to the additive value of the effects of the individual profiles.

Claims (2)

Example 1 Polypropylene fibers of the IT index 6 g / 10 min were prepared on a TS-16 threaded extruder. at a melt temperature of 270 ° C of 170 / 13dtex. The fibers had a mixture of the cross-sections shown in FIGS. 1-6, 14, 22, 23, 27, 28. The fibers after leaching had a strength of 2.5 cN / dtex, a ductility of 40%, a duller surface, a higher bulkiness and a higher surface area. o 40 í versus circular cross-section fibers. Example 2 Using the procedure of Example 1, using nozzles with holes shown in FIG. 7, 8, 10, 15, 29, 30, fibers having a higher moisture transport of about 20% and an improved feel compared to the additive value of the separately evaluated individual profiles were produced. EXAMPLE 3 Mixtures of polypropylene fibers with different transverse geometry were prepared on a T-90 discharge extruder at a melting point of 270 DEG C. with a fineness of 15,000/100 dtex. The fibers behind the spinneret were cooled with an aqueous solution, elongated with a lengthening ratio of 2 to 2. 8, had a strength of 2.4 cN / dtex and a 70% elongation. The cross-section of the fiber consisted of a combination of shapes according to Figure 7, 8, 15, 19, 25, 26. These fibers were characterized by a higher separation ability of 30% compared to the additive value of the separately evaluated profiles. The oil adsorption capacity of water of 1.2 kg / kg of fiber was achieved and the synergism of the effect of the individual profiles in their combination resulted. These filaments had increased sound absorption compared to filaments with a circular cross section of the same fineness up to 70µ. EXAMPLE 4 Polypropylene fiber mixtures with spit geometry were prepared on a T-90 discharge extruder at a melt temperature of 15,000/50 dtex at 280 ° C. The fibers behind the spinneret were cooled with an aqueous solution, elongated with a lambda extension ratio of 3, having a strength of 2.2 cN / dtex and 80% ductility. The monofilament cross-section was a combination of shapes as shown in Figures 1, 2, 3, 8, 9, 11, 12, 13, 14, 16, 24. These filaments were characterized by a higher deformation resistance of 35% in the offset. with an additive value calculated from the effect of each individual profile and a higher surface area as compared to a circular cross-section fiber. EXAMPLE 5 Using the procedure of Example 1, using nozzles with openings shown in FIG. 7, 10, 11, 15, 16, 18, 19, 20, 21 produced fibers with higher absorbency and higher separation effect (gas phase separation) min. 20 S compared to the additive value of the effects of the individual profiles. PATENT REQUIREMENTS A polypropylene fibrous structure, characterized in that it consists of a heterogeneous mixture of natural minerals, which are unorganized disposed in a given cross-section as well as in a filamentous shape and have the shape of a pestle, I, triadic form, cross, L, triangular pointed shape, W, A Segner wheel, a chain, an open equilateral triangle with symmetrical protrusions in the axes of the slope, an equilateral asymmetrically interrupted triangle with protrusions, three sticks with an angle of 60 ", a quadrilateral, two-sided unsymmetrical ridge, an equilateral intermittent triangle, whose axis is connected at its center, An equilateral triangle, C, an angular quadrilateral, an equilateral triangle, a symmetry cross, the shape of a broken roof, the shape of three moons, the axes of which form an angle of 60 ',face angular three-anchors, the shape of three symmetrically placed mesicidal lobes with centric projections pointing to the center of symmetry, G. 2 drawings