Fiber, polyolefin fiber, and manufacturing method of polyolefin fiber

Abstract

To provide a novel fiber capable of enhancing environmental load reduction.SOLUTION: A fiber including a polyolefin resin containing rice powder. Also, a polyolefin fiber including a polyolefin resin containing 1-10 mass% of rice powder. Also, a fiber including 60-99 mass% of a polyolefin resin, 1-10 mass% of rice powder, and 1-30 mass% of a compatibilizer. The polyolefin resin is preferably at least one selected from the group consisting of a polypropylene resin and a polyethylene resin.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to polyolefin fibers. [Background technology]

[0002] In recent years, the practical application of biomass plastics made from biomass has been progressing rapidly. Attempts have been made to produce various resins from biomass materials, and the use of biomass-derived raw materials is expanding (Patent Document 1, Patent Document 2).

[0003] In particular, there is a demand for utilizing inedible rice flour, such as old rice flour that is not suitable for consumption and crushed rice flour generated by rice flour confectionery manufacturers, which is not used as feed and is disposed of as such, and attempts are being made to manufacture polyolefin resins containing rice flour (Patent Document 3).

[0004] In addition, attempts have been made to produce starch fibers and fibers containing starch in vinyl alcohol aggregates as resin molded products using rice as a raw material (Patent Document 4, Patent Document 5). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-255743 [Patent Document 2] Japanese Patent Application Publication No. 2023-022453 [Patent Document 3] Patent No. 7191435 [Patent Document 4] Japanese Patent Application Laid-Open No. 2009-108426 [Patent Document 5] International Publication No. WO2023 / 276402 Summary of the Invention [Problem to be solved by the invention]

[0006] In the textile field, too, there is a demand for products made from materials that have a low environmental impact. However, starch fibers are limited to a few meters in length, and long fibers have not yet been realized. Fibers made from vinyl alcohol aggregates containing starch have low strength and are highly water-soluble. Polyolefin resins containing rice flour have the effect of reducing the environmental impact, but there have been no attempts to produce fibers from them, likely because they exhibit properties different from fossil-derived plastics.

[0007] Therefore, an object of the present invention is to provide a new fiber that can reduce the environmental load. Another object of the present invention is to provide a method for producing a fiber that can stably produce a new fiber that can reduce the environmental impact.Another object of the present invention is to provide a fiber that utilizes non-edible rice flour, does not significantly impair mechanical properties, and has excellent spinning operability while reducing the environmental impact. [Means for solving the problem]

[0008] After extensive investigation, the present inventors focused on incorporating rice flour itself into a polyolefin resin, and arrived at the present invention. Furthermore, the present inventors discovered that a fiber-shaped resin composition can be obtained without significantly impairing mechanical properties when the resin is made from a blend polymer in which a specific amount of rice flour is added to a polyolefin resin at a specific mixing ratio, thereby completing the present invention. Specifically, the object of the present invention is achieved by a fiber containing a polyolefin resin that contains rice flour. Another object of the present invention is achieved by a polyolefin fiber made from a polyolefin resin that contains 1 to 10 mass% rice flour. Another object of the present invention is achieved by a fiber containing 60 to 99 mass% polyolefin resin, 1 to 10 mass% rice flour, and 1 to 30 mass% compatibilizer. The present invention also relates to a method for producing polyolefin fibers by melt-spinning a resin composition containing 60 to 99 mass% polyolefin resin, 1 to 10 mass% rice flour, and 1 to 30 mass% compatibilizer. [Effects of the Invention]

[0009] According to the present invention, a new fiber that reduces the environmental load can be provided. Furthermore, according to the production method of the present invention, it is possible to obtain fibers that are excellent in spinning operability without significantly impairing mechanical properties while reducing the environmental load. DETAILED DESCRIPTION OF THE INVENTION

[0010] The fiber of the present invention is a fiber comprising a polyolefin resin containing rice flour. The polyolefin fiber of the present invention is a fiber made of a polyolefin resin containing rice flour.

[0011] Examples of the polyolefin resin in the present invention include polyethylene such as high-density polyethylene and medium-density polyethylene, polypropylene, acid-modified polypropylene, a resin composition containing polypropylene and maleic acid-modified polypropylene, a propylene-ethylene copolymer, a propylene-α-olefin copolymer, and polybutene-1.

[0012] In this invention, from the various polyolefin resins mentioned above, resins with a melting point of 170°C or less are appropriately selected in consideration of melt-blending with rice flour, and one of these resins can be used alone or two or more of them can be used in combination. Among them, resin compositions containing polypropylene and polyethylene are preferred.

[0013] The polyolefin resin content of the polyolefin fiber of the present invention is preferably 60 to 99% by mass, and more preferably 90 to 96% by mass. If the polyolefin resin content is 60% by mass or more, the fiber tends to be moldable into a fiber shape without significantly impairing the mechanical properties, and if it is 99% by mass or less, the environmental load tends to be reduced.

[0014] On the other hand, if the content of the polyolefin resin is less than 60% by mass, the mechanical properties tend to be significantly impaired and the material tends to be unable to be molded into a fiber shape.

[0015] Suitable raw materials for the rice flour in the present invention are those with a β structure (crystalline structure), such as polished rice, old rice, ginjo rice, and rice bran (medium-sized white flour). In particular, since rice bran is often discarded during the rice polishing process, using rice bran as rice flour is ecological, with a low environmental impact, and is also suitable from the perspective of life cycle assessment.

[0016] Rice flour may be incorporated into commercially available resin compositions containing rice flour, such as RiceRsin R55J-1 (manufactured by Biomass Resin Minamiuonuma Co., Ltd.) and RiceRsin R50E-4 (manufactured by Biomass Resin Minamiuonuma Co., Ltd.).

[0017] The rice flour content in the present invention is preferably 1 to 10% by mass, more preferably 2 to 5% by mass. A rice flour content of 1% by mass or more is more likely to reduce the environmental impact, while a rice flour content of 10% by mass or less is preferred because it does not significantly impair mechanical properties and is easy to mold into a fiber shape.

[0018] On the other hand, if the rice flour content exceeds 10% by mass, the mechanical properties tend to be significantly impaired and it becomes difficult to form the product into a fibrous shape.

[0019] The rice flour used in the present invention has an average particle size of 10 μm or less, preferably 5 μm or less. If the average particle size is 10 μm or less, it tends to be easier to form into a fibrous shape.

[0020] On the other hand, if the average particle size exceeds 10 μm, the mechanical properties tend to be significantly impaired and it becomes difficult to form the particles into a fiber shape.

[0021] The average particle size of rice flour can be calculated by observing the cross section of the fiber under an electron microscope, measuring the particle size of the rice flour in the field of view, and taking the arithmetic mean. In this case, if the number of grains is less than 30, measurements should be taken at different locations until the average value for a total of 30 or more grains is reached. If the rice flour is not circular, the diameter of its circumscribed circle is measured as the particle size.

[0022] In the present invention, a compatibilizer may be added for the purpose of uniformly dispersing rice flour in the polyolefin resin.

[0023] The compatibilizer may be a saturated carboxylic acid, an unsaturated carboxylic acid, or a derivative thereof. Examples of saturated carboxylic acids include succinic anhydride, succinic acid, phthalic anhydride, phthalic acid, tetrahydrophthalic anhydride, and adipic anhydride. Examples of unsaturated carboxylic acids include maleic acid, maleic anhydride, nadic anhydride, itaconic acid, itaconic anhydride, citraconic acid, sorbic acid, and acrylic acid. Examples of unsaturated carboxylic acid derivatives include metal salts, amides, imides, and esters of the unsaturated carboxylic acids. Polyolefin resins modified with unsaturated carboxylic acids or their derivatives may also be used. These can be obtained by heating and mixing a polyolefin, an unsaturated carboxylic acid or its derivative, and a radical generator in the presence or absence of a solvent. The amount of unsaturated carboxylic acid or its derivative added is preferably 0.1 to 15% by mass, and more preferably 1 to 10% by mass. The compatibilizer used in the present invention is preferably a polyolefin resin modified with an unsaturated carboxylic acid or its derivative, which is odorless and has low acidity.

[0024] The compatibilizer may be a commercially available product, and specific examples thereof include Eumex 1001 (manufactured by Sanyo Chemical Industry Co., Ltd.), Rikeaid MG-440P (manufactured by Riken Vitamin Co., Ltd.), MG-441P (manufactured by Riken Vitamin Co., Ltd.), and MG-250P (manufactured by Riken Vitamin Co., Ltd.).

[0025] Only one of these compatibilizers may be used, or two or more may be used in combination as needed. It's fine.

[0026] The content of the compatibilizer in the present invention is 1 to 30% by mass, preferably 3 to 15% by mass, based on the total mass of the fiber. If the content of the compatibilizer is 1% by mass or more, the rice flour dispersion effect is high, and if the content is 30% by mass or less, the mechanical properties are not significantly impaired and the fiber tends to be easily molded into a fiber shape.

[0027] In the present invention, polyolefin resin, rice flour, and a compatibilizer may be mixed and then directly charged into a melt spinning apparatus for spinning. Alternatively, polyolefin resin, rice flour, and a compatibilizer may be mixed in advance and melt-kneaded in a melt kneading apparatus, and the resulting resin may be melt-kneaded for melt spinning. The latter method is preferred in terms of uniformly dispersing rice flour in the polyolefin resin.

[0028] The total fineness of the polyolefin fiber of the present invention is not particularly limited and may be the same as that used for ordinary polyolefin fibers. From the viewpoint of spinning operability and mechanical strength, it is preferably 1 to 300 dtex. Of these, a fiber having a fineness of 1 to 100 dtex is suitable mainly for clothing applications. Furthermore, a fiber having a fineness of 30 to 300 dtex is suitable for vehicle applications.

[0029] The polyolefin fiber of the present invention preferably has a single filament fineness of 0.8 to 25 dtex. If the single filament fineness is 0.8 dtex or more, good strength is likely to be maintained when the fiber is used mainly for clothing applications.

[0030] The polyolefin fiber of the present invention preferably has a strength of 1.5 cN / dtex or more. It is more preferably 2.0 cN / dtex or more, even more preferably 2.5 cN / dtex or more, and particularly preferably 3.0 cN / dtex or more. A strength of 1.5 cN / dtex or more provides good spinning operability and processability in the knitting and weaving process, and the fiber can be used in the same applications as polyolefin fibers.

[0031] The polyolefin fiber of the present invention preferably has an elongation of 30% or more, more preferably 40% or more, and particularly preferably 50% or more. If the elongation is 30% or more, the spinning operability and processability in the knitting and weaving process are good, and the fiber can be used in the same applications as polyolefin fibers.

[0032] The polyolefin fiber of the present invention preferably has a strength-strain product of 8 or more, more preferably 17 or more, and particularly preferably 20 or more. If the strength-strain product is 8 or more, the fiber is durable and can be used in the same applications as polyolefin fibers.

[0033] The cross-sectional shape of the polyolefin fiber of the present invention may be circular or irregular, such as multi-lobed, triangular, flat, or elliptical.

[0034] The polyolefin fibers of the present invention can be used as they are as long fibers. They can also be used as woven or knitted fabrics by weaving or knitting. They can also be processed from long fibers to be used as staple fibers, or they can be used as batting. Polyolefin fibers can also be used by converting them into staple fibers or directly into nonwoven fabrics. [Example]

[0035] The present invention will be specifically explained below by way of examples, but the present invention is not limited to these examples.

[0036] Details of the raw materials listed in Table 1 are given below. PP: Prime Polypro J106 (Prime Polymer Co., Ltd.) PE: Novatec HJ560 (Japan Polyethylene Co., Ltd.) Rice flour-based material 1: RiceRsin R50E-4 (manufactured by Biomass Resin Minamiuonuma Co., Ltd.) Rice flour-based material 2: RiceRsin R55J-1 (manufactured by Biomass Resin Minamiuonuma Co., Ltd.) Compatibilizer: Eumex 1001 (manufactured by Sanyo Chemical Industries, Ltd.)

[0037] In the examples, kneading, measurement of yarn properties, and evaluations were carried out as follows.

[0038] (Kneading) The raw materials shown in Table 1 were mixed, melt-kneaded at 230°C in a twin-screw melt-kneading extruder, extruded into a cord-like shape, cooled with water, and pelletized to obtain a kneaded resin.

[0039] (Tensile test) Measurements were performed in accordance with JIS L 1013:2021 using a Shimadzu AGS-1kNG Autograph (registered trademark) tensile tester with a sample length of 200 mm and a constant tensile speed of 200 mm / min. The breaking strength (cN / dtex) was calculated by dividing the maximum load on the load-elongation curve by the fineness, and the breaking elongation (%) was calculated by averaging the values ​​three times.

[0040] (strong elongation product) The strength-strain product was calculated using the following formula.

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[0041] (Threadability) The resin, which was made by mixing or kneading the raw materials, was melt-extruded at 220°C using an extruder, wound up at a peripheral speed of 1500 m / min, and then stretched 2.4 times at a peripheral speed of 400 m / min to produce polyolefin fiber of 56 dtex / 24 f, and the spinnability was evaluated. The spinnability was evaluated as follows. 〇: Can be stretched and wound ×: Stretching and winding not possible

[0042] (Filtration pressure increase rate) The resin, which was a mixture or knead of raw materials, was melted at 220°C in an extruder, passed through a φ85mm 30μm metal nonwoven filter, and extruded at a rate of 1.0 kg / h from a 24-hole spinneret with a hole diameter of φ0.5mm. The pressure measured by the pressure gauge attached to the spinneret was recorded, and the rate of increase in pressure after 3 hours relative to the pressure value at the start of melt spinning was evaluated. The rate of increase in filtration pressure was determined as follows: 〇: 0MPa or more and less than 5MPa / h △: 5 MPa or more and less than 10 MPa / h ×: 10MPa / h or more

[0043] (Examples 1 to 9, Comparative Examples 1 to 3) The resin kneaded with the raw material ratios shown in Table 1 was melted at 220°C in an extruder, passed through a φ85mm 30μm metal nonwoven fabric filter, and extruded from a 24-hole spinneret with a hole diameter of φ0.5mm, taken up at a peripheral speed of 1500m / min, and then stretched 2.4 times at a peripheral speed of 400m / min to produce a polyolefin fiber of 56dtex / 24f. The obtained polyolefin fiber was evaluated by the methods described above. Comparative Example 4 In Comparative Example 4, polyolefin fibers were produced in the same manner as in Example 1, except that a resin kneaded with the raw material ratios shown in Table 1 was melted at 220°C in an extruder, passed through a φ85 mm metal 325 mesh filter, and extruded from a 24-hole spinneret with a hole diameter of φ0.5 mm. The filtration pressure increase rate of Comparative Example 4 was evaluated in the same manner as in Example 1, except that a 325 mesh metal filter was used. The evaluation results are shown in Table 1.

[0044] [Table 1]

[0045] Examples 1 to 3, 5 to 6, and 8 to 9 showed sufficient strength and elongation, and had good spinnability and could be wound up. In addition, the rate of increase in filtration pressure was low and good.

[0046] The fibers of Examples 1 to 6 had high strength-strain products and excellent durability.

[0047] Examples 4 and 7 exhibited sufficient strength and elongation, and had good spinnability, allowing winding.

[0048] Comparative Example 1 had a high rice flour content, and had poor spinnability, making it impossible to wind.

[0049] Comparative Example 2 contained a large amount of compatibilizer, and had poor spinnability, making it impossible to wind.

[0050] Comparative Example 3 had a low polyolefin resin content, and had poor spinnability, making it impossible to wind.

[0051] In Comparative Example 4, the rice flour had a large average particle size, and the spinnability was poor, making it impossible to wind.

Claims

1. A fiber comprising a polyolefin resin containing rice flour.

2. A polyolefin fiber made of a polyolefin resin containing 1 to 10% by mass of rice flour.

3. Fibers containing 60 to 99% by mass of polyolefin resin, 1 to 10% by mass of rice flour, and 1 to 30% by mass of a compatibilizer.

4. 4. The fiber according to claim 1, wherein the polyolefin resin is at least one selected from the group consisting of polypropylene resin and polyethylene resin.

5. The fiber according to any one of claims 1 to 3, wherein the rice flour has an average particle size of 10 µm or less.

6. The fiber according to any one of claims 1 to 3, having a strength of 1.5 cN / dtex or more.

7. A method for producing polyolefin fibers by melt spinning a resin composition containing 60 to 99% by mass of polyolefin resin, 1 to 10% by mass of rice flour, and 1 to 30% by mass of a compatibilizer.

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