CS248085B1 - Additive to polypropylene to reduce breakage and reduce waste when polypropylene fibers are drawn - Google Patents

Abstract

The purpose of the invention is to reduce the breakage and reduce the amount of waste during the spinning of polypropylene fibers. The stated purpose is achieved by using as an additive a mixture of 0.01 to 3, preferably 0.05 to 0.25% by weight of zinc stearate with 0.01 to 1.5, preferably 0.03 to 0.25% by weight of calcium stearate. All additive amounts are calculated on the basis of the final fiber. The invention can be used in the preparation and processing of polypropylene fibers.

Description

248085

BACKGROUND OF THE INVENTION The present invention relates to the production of polypropylene-coated fibers. The amount of waste generated during this production is mainly due to the breakage of the polypropylene fibers.

Modification of polypropylene as well as its mixtures with pigments and other ingredients is effective in reducing bursting and reducing the amount of wastes in the polypropylene fibers. In the literature, including the patent, there is a lack of data on waste reduction and the number of polypropylene fiber breaches when small amounts of zinc and calcium stearate mixtures are added. While small amounts of the aforementioned liquids are not used to reduce the number of breakages and the amount of polypropylene waste and mixtures thereof with ingreens commonly used in the preparation of fibers and other articles.

In the use of stearates as additive for reducing bursting and reducing the amount of debris during cutting of polypropylene fibers, 0.01 to 3, preferably 0.05 to 0.25% by weight of zinc stearate 0.01 to 1.5, preferably 0, are mixed. 03 to 0.25% by weight of calcium stearate with polypropylene. All the amounts of additives are calculated on the basis of the final fiber.

The above-mentioned additives in process conditions can be added to the powdered polypropylene prior to the preparation of the pigment concentrates when mixing these and other ingredients, preferably in a turbo-blender. Furthermore, it is possible to prepare separate concentrates either from individual stearates, preferably up to 20%, or from a combined mixture of both stearates in the powdered polypropylene when mixed, preferably in a turbo-blender and re-melting the mixture and then adding it as a granulate . The dispenser is made by means of a volumetric dispenser in the fibrillation stage into either a base or a secondary fusion screw.

Optionally, the addition of a pure additive prior to granulation of the polymer layer is possible. The mixing of the additive with the polypropylene and its mixtures is carried out in process mixing devices with conventional conditions. The resulting mixture is melted in a melting apparatus. At the same time, the melting temperature of the mixture, the transport and the melt spinning is desirable to obtain a melt index with a preference of 1 to 15 g / 10 min higher compared to the conventional allowance index of a given color shade. Thereafter, the sanitized fiber is scaled. The melt index was determined on a Gotfert plastomer according to the standard.

The number of tears per tonne, and hence the waste from the scraped non-woven fiber, is much less when added to the polypropylene amounts of zinc stearate and calcium stearate compared to the propylene fiber without added stearates. This effect of small amounts of the above-mentioned stearates is new. It is based on the influence of these additives to improve recovery 4 properties, structural stabilization and synergism in the polymer.

In the aforementioned ratios, the additives become interacting with each other, with the polypropylene, optionally with other components of the polymer system. This synergistic effect contributes to obtaining a new effect.

As an advantage of the present invention, the use of additives in small amounts of accessible, inexpensive and biologically harmless substances, such as zinc stearates and calcium foams, is preferred. A further advantage of the present invention is that of an accessible, simple and economical process using mechanical mixing and drawing - conventional process steps in the preparation of fibers and plastic products. Therefore, for the other advantages mentioned, the use of stearates according to the invention is advantageously advantageous. Example 1

The used Tatren TE 451 branded granulated polypropylene at 230 ° C and the plasticizer paste loading of 2.16 kg had a melt index of 3.89 to 4.78 g / 10 min as well as a pseudo-plasticity index of 1.66. Polypropylene Powder HPT had a melt index of 35.31 g / 10 min at 230 ° C and a load of 2.16 kg. When the test mixtures are made, the mandatory anti-static materials used in normal production are not added. Prepared in a food mixer by stirring mechanically over a 20 min co-mixture of zinc stearates and calcined into polypropylene powderTatren HPF was melted in a "Sikoplast" mono-worm granulator with a screw diameter of 80 to 125 mm at temperatures of: I. zone 240 ° C, II. zone 230 ° C, III. zone 180 ° C, IV. zone 180 O, V zone 220 ° C, head 240 eC, oil heating 220 ° C, degassing 170 ° C.

The molded strings of the mixture after aqueous and air-blowing cooling were cut into the granules by a cutting device. The 21.24 g / 10 min melt index thus obtained was homogenized in a food mixer. To monitor the efficacy of the combination of estearates, their combined mixture into powdered HPF was added to polypropylene Tatren TF 411 in a suitable ratio of final fiber. Therefore, the stearate mixtures were metered into a secondary extruder with a screw diameter of 32 mm, where it was melted and then mixed with the Tatren TE 451 polypropylene melt in a base mill with a screw diameter of 90 mm.

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The melting and spinning conditions were: extruder side temperature I. zone 250-260 CC, II. zones 255 to 260 G, III. zone 255-260 ° C; extruder output 11.524 kg / h; the heating temperature of the tube cuff between the extruder and the base melter 260 ° C; the resistance heating temperature of the base melt aggregate 245-260 aC; the temperature of the dinyl pair at the base melt aggregate: zone I 250-260 ° C, µl. zone 250-260 C1C; dinylene vapor temperature at 250 ° C; the temperature of the spinning stations 250-260 ° C; melt pressure beyond the melting portion of the basic aggregate 6.9 MPa, downstream of the pump pump up to 9 MPa, behind the secondary extruder 5.9 MPa; basic power of the unit 55.8 kilograms / h; melt dispensing at one spinning site 310 g / min; spinning nozzles with holes in the form of letter Y; tow speed PD-1450 m / min; total unbound fiber titer 7 040 to 7 780 dtex.

Comparative Tatren TE 451 polypropylene polypropylene alone, without addition of stearates, was simultaneously fed to the secondary extruder and base plate 1

Assay Melt index at 230 ° C in g / 10 min under the melt aggregate spinneret, melted and spun at conditions similar to the above stearate assay. Debossing was performed on a KK-2 cutter at temperatures of galetes of 120-125 ° C and 104 ° C, irons of 45-70 ° C; speeds - ranging from 287 to 288 m / min, galets under the iron from 270 to 271 m / min, ga-tops from 338 to 340 m / min; tension - between 6th and 7th bell 200 to 210 cN, at 700 to 800 cN winding.

Twisting the thread on the "Verdol" machine / under normal conditions. The efficacy of a combination of 0.2% by weight stearate and 0.2% by weight zinc stearate was observed in crude, i.e., polypropylene-free fiber (A) pigments. The values obtained were compared with the values of the fiber cable from the TatrenTE 451 granular polypropylene alone without the addition of stearates (O. The physical-mechanical properties and other parameters of prepared cut and twisted fiber glass A in a total of 2724 dtex titer allowed its classification to first quality). It can be seen from Table 1 that the formed waste of the cut non-woven fiber is present when adding to the polypropylene the combination of calcium stearates of 0.2 wt% and zinc 0.2 wt%. This effect of the aforementioned stearate mixture is new and higher In the case of the said amount of stearate mixture, the flowability of the melt is considerably increased, considering the increase in the melt index, which allows a reduction in energy costs.

Observations during the tests showed that fibers containing a combination of stearate-calcined 0.2 wt. and zinc 0.2% by weight. the spinning and cutting process is easier compared to the fiber from the TE 451 alone without the addition of stearates. In the case of the cut non-woven fiber with added stearates in the above-mentioned combination, the defect "small strings (ka-pillars)" was not seen on the fiber from the fiber O.

Waste of cut uncut fiber (%) 13,89 6,68 1,9 15,7 2 8 O 8 5 Example 2 Prepared in a mixer either 15 ° by weight of zinc stearate or 15% by weight of calcium stearate into the powder Tatren HPF poly-propylene was extruded in a 28 mm diameter screw extruder and the formed strands were cut into a granulation cutter. To monitor the efficacy of the combination of stearates, the components are dosed with the required ratio calculated on the final strand.

Mechanical agitation of 15% w / w pigment concentrates. mixtures of zinc stearate together with 15 wt. the stearate calcium mixture was carried out in a food mixer within 10 min. The homogenized mixture of pigments and stearates was metered into a 45 mm diameter extruder with a dispenser, melted and then blended with the molybdenum propylene of the Mosten56 532 brand in a 90 mm screw auger base. The melting and spinning conditions hurt: the temperature of the secondary ex-zone I zone 255 ° C, II. zone 230 ° C, III. zone 230 ° C; the temperature of the tube between the secondary extruder and the base melter 230 ° C; the dinylene temperature at the same melting point of 297 ° C, filter temperature 280 ° C; dinylene vapor temperature at distribution points 285 ° C;

Table 2

Assay Melt Index at 230 ° C in g / 10 min spinneret A 13.8, 21.60 O 11.3 24.46 The values obtained were compared to the values of polypropylene fiber containing the above pigments without the addition of stearates ( O), that is, the fiber produced under the same conditions, the device and the average quantity.

The physico-mechanical properties of the prepared cut and twisted fiber of the Av test of 4,071 dtex were: tensile strength 1.69 to 1.72 cN / dtex, ductility 53.1 to 66.2 ° / o; 0 to 24.0 ° / o shrinkage 1.9 to 3.1%; 8 melt dispensing per spinneret 300 g / min; tensile speed of winding machine NSK-3460 m / min; total unbound fiber titer 6,680 as well as 2902 dtex; retention of the preparation on the 13.39-percent long-fiber.

The unbonded fiber was cut and shaped by a "Pneu-tex" blowing machine under conditions of cutting ratio 3, a relaxation ratio of 0.745, a speed of splitting gallons of 1300 m / min, and a dwelling temperature of 123-135 ° C.

The number of ruptures was assessed from the number of irregulars obtained after its weight of the vessel was expressed per tonne of fiber produced consisting of regular and irregular vessels. The efficacy of combining calcium stearates with 0.08 wt. % azine 0.13 wt. into a polypropylene fiber in the presence of pigments

Cromophtal gelb GR 0.0744 wt%, Cromophtal scharlach R 0.0156 wt%, Nylofil schwarz BLN 0.0186 wt%; {AJ. Essentially, the efficacy of the above-mentioned combination of stearates was monitored in one of the most difficult processable pale color shades of polypropylene cable yarn.

The number of tears per tonne of fiber-brushed cut uncut

Wasteshuntedfibre,% 42.5 6 110.90 10 broken capillaries per 50 m of fiber2.2; number of turns 35 m-1; titer deviation +1.78 ° / o.

Fiber was classified in the first quality. From Table 2 it can be seen that the number of tears per ton and hence the waste of the scraped fiber is much lower at the addition of the calcium stearate combination of 0.08 wt%. and zinc 0.13 wt. In the case of said small amount of a mixture of stearates, the liquid

Claims (1)

243033 10, the melt strength assessed from an increase in the melt index, which allows a reduction in energy costs. The effect of stearates is of practical significance for the desired improved properties in polymerized systems with impaired prehistory, such as wastes. The aforementioned invention is of application importance for reducing pre-cracking and reducing waste by adding polypropylene fibers prepared from conventional raw materials, various types of aphorisms of wastes as well as a mixture of wastes with conventional raw materials. Other possibilities for use and advantages of the invention are: - reduction or increase of orientation, network of crystallinity and secondary terystallization of reduced fibers; - slightly suppressing the increased crystallinity of polypropylene as a result of the effect, certain content and types of pigments that make the polymer difficult to spin, because the fiber is hard enough, inelastic and increases the amount of waste; - regulating the structure, elasticity, clotting and stiffness of cut fibers, including those used for hygenic skin; - increasing or decreasing the thermal stability or degradation of polypropylene, which may be of use in the preparation of classical as well as precipitation fibers; - the possibility of improving physical and antistatic properties, reducing friction and adhesion to warm metal surfaces of manufacturing machines and equipment, avoiding changes in fiber color; - the possibility of reducing energy consumption, pre-paration, stabilization and dispersion systems; - the ability to carry out the process of deliberation under the most severe conditions; - Reduction of defects and color bandwidth. OBJECTIVE Use of a mixture of zinc and calcium stearates as an additive to polypropylene to reduce breakage and reduce the amount of waste when cutting polypropylene fibers. 9)