WO2006016499A1

WO2006016499A1 - Thermoplastic resin fibers for the reinforcement of cement

Info

Publication number: WO2006016499A1
Application number: PCT/JP2005/014072
Authority: WO
Inventors: Kazumasa Nakashima; Michio Okuhira
Original assignee: Hagihara Industries Inc.
Priority date: 2004-08-09
Filing date: 2005-08-02
Publication date: 2006-02-16
Also published as: JP2007284256A

Abstract

The invention provides thermoplastic resin fibers for the reinforcement of cement which have permanent hydrophilicity and are therefore excellent in the dispersibility in cement and the physical bonding with cement and which can give cement moldings improved in bending toughness. A thermoplastic resin fiber (particularly polypropylene fiber) according to the invention is produced by subjecting a thermoplastic resin fiber to surface oxidation, applying a surface treatment containing at least one compound selected from among sulfonic acids, polyol complexes, and polycarboxylic acids to the surface-oxidized thermoplastic resin fiber to make the compound adhere to the surface of the fiber in an amount of 0.1 to 5 wt%, and then drying the resulting fiber at 20 to 90˚C. The obtained thermoplastic resin fiber has further improved hydrophilicity as compared with the hydrophilicity imparted by the surface oxidation alone and is therefore excellent in the dispersibility in cement and the physical bonding with cement, thus enabling the production of cement moldings excellent in bending toughness and bending tenacity.

Description

Specification

Cement-reinforced thermoplastic fiber

Technical field

[0001] The present invention relates to a thermoplastic resin fiber for cement reinforcement having an excellent reinforcing effect for concrete or mortar.

Background art

[0002] Conventionally, cement molded products using mortar and concrete, or the strength of building outer walls, tunnel inner walls, slope slopes, etc. These are relatively brittle as molded bodies, If physical properties such as tensile strength, bending resistance, bending toughness, and impact resistance are not sufficient, there is a risk of water leakage due to cracks on the wall surface or peeling and dropping accidents on the outer wall. For the purpose of reinforcing concrete, mixing of steel fibers or polybulal alcohol fibers (for example, Patent Document 1) is widely performed. When shotcrete requires bending strength and toughness, a reinforcing wire mesh will be installed.

[0003] However, the concrete mixed with steel fibers is difficult to transport and mix with the material because the specific gravity of steel fibers is as high as 7.8, and in sprayed concrete, it falls due to rebounding during spraying. It has been pointed out that there is a high risk of injury due to trampling of the damaged steel fibers, and that the steel fibers are glaring. In addition, the concrete mixed with polybulualcohol fiber has water absorbency, and when the fiber is alkali and high in temperature, it hydrolyzes, and the slump is significantly reduced compared to the fiber not mixed with fiber. This tends to cause inconveniences such as the need to increase the unit water volume to secure the slump required for spraying.

[0004] In order to solve such problems, in recent years, there have been attempts to use polyolefin fibers instead of steel fibers and polyvinyl alcohol fibers for reasons such as good formability, light weight, and low cost ( For example, Patent Document 2).

Polyolefin fibers are generally single yarns, bundled yarns, or split yarn short fibers having a fineness of lOOdt or less and a fiber length of 5 mm or less. This fiber shape force is also a property, and a fiber lump called a fiber ball is formed with short fibers with low fineness. However, if the fineness is increased to improve the dispersibility, the fiber will be pulled out if the adhesion to the cement is poor and bending stress is applied. There is a tendency that a sufficient reinforcing effect cannot be obtained.

[0005] In order to improve the hydrophilicity of the powerful polyolefin resin fiber cement, the polyoxyalkylene alkylphenol phosphate ester and the polyoxyalkylene fatty acid ester carbonate are added to the polypropylene fiber with irregularities in the fiber cross section. (For example, Patent Document 3), the above-mentioned proposed surfactant does not have sufficient adhesion to polyolefin resin fibers. For this reason, even if the cement matrix and the surfactant are bonded, there is a problem that the adhesive strength between the polyolefin resin fiber and the matrix cannot be sufficiently obtained, and the bending toughness of the cement molded product is not sufficient.

[0006] In order to improve the problem of such a polyolefin resin, the present applicant has decided to add a thick monofilament having a single yarn fineness of 200 dt or more with irregularities having a specific average flatness to the fiber cross section. We proposed a method of subjecting polypropylene fibers cut to a length of 5 mm or longer to surface oxidation treatment such as corona discharge treatment, plasma treatment, flame plasma treatment, electron beam irradiation treatment, and ultraviolet irradiation treatment (for example, Patent Document 4). ).

However, in the proposed method of surface oxidation treatment, the treatment effect diminishes over time due to the change in the oxidation treatment effect over time, and sufficient adhesion between the polyolefin resin and the matrix cannot be obtained. There was a problem that the bending toughness of the cement molding was not sufficient.

Patent Document 1: Japanese Patent Publication No. 1-40786 (1 page)

Patent Document 2: JP-A-9 86984 (2 pages)

Patent Document 3: Japanese Patent Laid-Open No. 11 116297 (2 pages)

Patent Document 4: Japanese Unexamined Patent Application Publication No. 2004-168645 (2 pages)

Disclosure of the invention

Problems to be solved by the invention

[0007] The present invention was made in order to solve the problems of the prior art as described above, and can permanently impart hydrophilicity to thermoplastic resin, particularly polypropylene-based resin fiber, Seme It is an object of the present invention to provide a cement-reinforced thermoplastic resin or polypropylene-based resin fiber that has good dispersibility with the cement and physical bond with the cement and improves the bending toughness of the cement molded product.

Means for solving the problem

[0008] In order to technically solve the above problems, the present invention performs surface oxidation treatment on a thermoplastic resin fiber, in particular, a polypropylene resin fiber, and coats the oxidized surface with a specific surface treatment agent. The inventors have found that the above-described object can be achieved by performing a drying process, and have completed the present invention.

That is, the first gist of the present invention is that the surface of the thermoplastic resin fiber is subjected to surface oxidation treatment, and the sulfonic acid compound, polyols and polycarboxylic acid compound force are also selected on the surface. A thermoplastic resin fiber for cement reinforcement characterized by adhering 0.1 to 5% by weight of at least one kind of compound, and the second gist is that the fiber is spun from polypropylene-based resin. A surface oxidation treatment is applied to the fiber surface, and at least one selected compound or mixture of two or more selected sulfonic acid compounds, polycarboxylic acids and polyols is adhered to the surface by 0.1 to 5% by weight. The characteristic feature is polypropylene fiber for cement reinforcement.

The invention's effect

[0009] The thermoplastic resin fiber for cement reinforcement of the present invention is subjected to surface oxidation treatment on the surface of the fiber of the thermoplastic resin, in particular, the surface of the polypropylene fiber, and is then used as a surface treatment liquid. The hydrophilicity imparted by the oxidation treatment of the fiber surface by applying a specific amount of at least one compound of a compound, a polyol complex or a polycarboxylic acid compound and applying it by drying. A thermoplastic resin fiber that can improve the dispersibility of cement and physical bond with cement, and can produce cement moldings with excellent bending toughness and bending toughness of cement moldings, In particular, polypropylene fibers can be obtained.

BEST MODE FOR CARRYING OUT THE INVENTION

[0010] The thermoplastic resin used in the present invention is not particularly limited, but is not limited to polyolefin resin, polychlorinated bur, polyester, polyamide, polybulal alcohol, poly Examples thereof include styrene. Examples of polyolefin resin include high-density polyethylene, medium-density polyethylene, linear low-density polyethylene, ethylene-a-olefin copolymer produced using a meta-octane catalyst, polypropylene-based resin, and polybutene. 1. Poly-4-methylpentene 1, ethylene acetate butyl copolymer, ethylene acrylate ethyl copolymer, maleic anhydride modified polyolefin, etc. are used, but power polypropylene-based resin is preferred. As the polyester, polyethylene terephthalate, polybutylene terephthalate, or the like is used.

[0011] As the polypropylene-based resin, a polypropylene copolymer such as a propylene homopolymer, an ethylene-propylene block copolymer or a random copolymer, or a mixture thereof can be used. Of these, propylene homopolymers are particularly desirable for cement reinforcement where high strength and heat resistance are required, and it is particularly desirable to select those having an isotactic pentad ratio of 0.95 or more. This polypropylene resin melt melt rate (hereinafter abbreviated as MFR) is selected in the range of 0.1 to 30 g / 10 min, preferably l to 10 g / 10 min in terms of continuous and stable productivity. It is good.

[0012] In addition, other polyolefins may be added to the polypropylene-based resin as necessary. Other polyolefins here include high-density polyethylene, linear low-density polyethylene, low-density polyethylene, ethylene acetate butyl copolymer, ethylene alkyl acrylate copolymer, and other polyethylene-based resins, polybutene 1, etc. is there.

[0013] As a form of drawn yarn that also has thermoplastic resin fiber strength, a flat yarn obtained by slitting a film, a split yarn obtained by splitting a flat yarn, a monofilament obtained by drawing a filament that also extrudes a spinning nozzle force, The ability to use multi-filaments with converged low-definition filaments. Flat yarns and monofilaments are preferred.

[0014] The case where polypropylene-based resin is used as the thermoplastic resin is described in detail below.

When flat yarn is used as the form of the drawn yarn, first, polypropylene is melt-kneaded with an extruder, a film is formed by a T-die method or an inflation method, and a formed film (hereinafter, undrawn) is used. (Referred to as film) is slit and then stretched, and then heat treated to form a flat yarn. Stretching is performed at a temperature below the melting point of polypropylene and above the softening point. Heating methods include hot roll type, hot plate type, infrared type, hot air. Any of these methods can be employed, and among these, the hot roll method is preferable in view of stretching efficiency, high-speed productivity, and stability. The slit polypropylene film is heated and stretched by the difference in peripheral speed between the front and rear rolls. The draw ratio is 5 times or more, preferably 7 to 15 times, more preferably 9 to 13 times.

[0015] When a monofilament is used as the drawn yarn, the production method is not particularly limited, and a production technique for extruding a circular, elliptical, irregular, or other continuous yarn-shaped die force filament is used. Can be adopted.

[0016] Further, in addition to the basic single-layer filament, a composite monofilament having a polypropylene high-melting component as a core layer and a polypropylene low-melting component as a sheath layer can also be used as the monofilament structure. In this manufacturing method, polypropylene of each layer is melt-kneaded with an extruder, and a core layer made of a high melting point component is supplied from a central discharge hole of a die in which two layers of discharge holes are provided on a substantially concentric circle. A composite monofilament is obtained by extruding and coating a sheath layer having a melting point component force. In this case, since the substantial strength depends on the physical properties of the core layer, it is preferable to use a propylene homopolymer, a isotactic polypropylene or the like as the high melting point component, while propylene ethylene propylene is used as the low melting point component. Copolymers, random copolymers and syndiotactic polypropylene are preferred. By using the composite monofilament thus obtained, it is possible to suppress thermal deterioration of the polypropylene fiber during heat curing during concrete molding.

Next, the monofilament is subjected to heat stretching and heat relaxation treatment, and the rigidity of the filament is increased by this heat treatment to obtain a polypropylene monofilament suitable for cement reinforcement having a small elongation. This hot drawing is performed at a temperature below the melting point of polypropylene and above the softening point. Usually, the drawing temperature is 90 to 150 ° C, and the draw ratio is usually 5 to 12 times, preferably? ~ 9 times. As the hot stretching method, methods such as a hot roll method, a hot plate method, an infrared irradiation method, a hot air oven method, and a hot water method can be adopted.

[0018] The tensile strength of the flat yarn or filament of polypropylene is 5 g / d or more, and preferably 6 g / d or more. Further, the tensile elongation is 20% or less, preferably 15% or less. If the tensile strength and tensile elongation are outside these ranges, the strength as a polypropylene fiber for cement reinforcement is insufficient, which is preferable! [0019] The single yarn fineness of the formed flat yarn or filament of polypropylene is in the range of 5 to 10,00 Odt, preferably in the range of 200 to 6,500 dt. If the single yarn fineness is less than 200 dt, the fibers are too thin and the dispersion in the concrete mixture is uneven and tends to become fiber balls, which causes problems in terms of workability and reinforcement. On the other hand, if the single yarn fineness exceeds 10,000 dt The contact area of the fiber with the concrete admixture is reduced, and it tends to be pulled out with respect to bending stress.

[0020] Therefore, the flat yarn or filament of polypropylene needs to have irregularities on the surface as the next step of hot drawing. As a result, the contact area between the fiber and the concrete can be increased, and the reinforcing effect can be enhanced by suppressing the pull-out of the fiber after the concrete is hardened. Examples of a method for forming irregularities on the surface include a method of embossing a flat yarn or a filament. Embossing is performed by passing a flat yarn or filament through an embossing roll before or after stretching, so that unevenness is continuously formed in the longitudinal direction of the flat yarn or filament.

[0021] Here, the shape such as the length and depth of the emboss may be arbitrary, but the average flatness ratio of the fiber cross section by crushing is in the range of 1.5 / 1 to 7/1, preferably 1.8 / 1 to It needs to be 7/1. This average flatness is a numerical value showing the average ratio of width and height in the cross-sections of various shaped shapes. If the average flatness is less than 1.5 / 1, While there are few uneven shapes, there is no difference in the reinforcing effect from smooth surface fibers.On the other hand, when the average flatness ratio exceeds 7/1, strength deterioration due to shaping is significant. Dispersibility in concrete tends to be poor, which is a problem.

[0022] The polypropylene fiber includes an antioxidant, a lubricant, an ultraviolet absorber, an antistatic agent, an inorganic filler, an organic filler, a crosslinking agent, a foaming agent, a nucleating agent and the like without departing from the gist of the present invention. These additives may be blended.

[0023] In the present invention, the surface of the polypropylene fiber is subjected to a surface oxidation treatment, and the surface has a wet tension of 40 mN / m or more, preferably 40 to 70 mN / m. And If the surface wetting tension is less than 40 mN / m, hydrophilicity cannot be sufficiently imparted to the polyolefin resin fiber, and the bending strength and impact strength of the cement molded product cannot be increased. It cannot be improved. The wetting tension is a value based on “JIS K 6768 Wetting Tension Test Method”.

The surface oxidation treatment is at least one treatment method selected from corona discharge treatment, plasma treatment, flame plasma treatment, electron beam irradiation treatment, and ultraviolet irradiation treatment, and corona discharge treatment and plasma treatment are preferred.

[0024] Corona discharge treatment is a treatment condition that is usually used, for example, a distance of 0.2 to 5 mm between the electrode tip and the substrate to be treated. The treatment amount is 10 W 'min or more per lm ^{2 of} polypropylene fiber. The range is preferably 10 to 200 W. min, and more preferably 10 to 180 W. min. If it is less than 10 W 'min / m ² , the effect of corona discharge treatment is insufficient, the wetting tension of the fiber surface cannot be within the above range, and the bending strength and impact strength of the cement molded product are improved. I can't.

[0025] The plasma treatment step is performed by using a single gas such as argon, helium, krypton, neon, xenon, hydrogen, nitrogen, oxygen, ozone, carbon monoxide, carbon dioxide, sulfur dioxide or a mixed gas thereof, for example, A plasma jet is generated electronically by generating a plasma discharge by applying a voltage between counter electrodes under a pressure close to atmospheric pressure with a mixed gas of oxygen and nitrogen containing an oxygen concentration of 5 to 15% by volume. After excitation, the charged particles are removed, and an electrically neutral excitation mixed gas is sprayed onto the surface of the plastic substrate. As plasma treatment conditions, for example, the distance between the electrodes through which the plastic substrate to be treated passes is a force that is appropriately determined according to the thickness of the substrate, the magnitude of the applied voltage, the flow rate of the mixed gas, etc. Preferably, it is in the range of 2 to 30 mm, and the voltage applied between the electrodes is preferably applied so that the electric field strength at the time of application is 40 kV / cm. The frequency of the AC power supply at that time is l is in the range of 100kHz.

[0026] The flame plasma treatment step can be carried out by blowing ionized plasma in a flame generated when natural gas or propane is burned onto the surface of the plastic substrate.

[0027] The electron beam irradiation treatment step is performed by irradiating the surface of the plastic substrate with an electron beam generated by an electron beam accelerator. As an electron beam irradiation device, for example, a device that can irradiate a uniform electron beam in the form of a curtain from a linear filament "elect mouth curtain" ( Product name) can be used.

[0028] The ultraviolet irradiation treatment step is carried out, for example, by irradiating the surface of the plastic substrate with ultraviolet rays having a wavelength of 200 to 400 µm.

[0029] In the present invention, after the surface of the polypropylene fiber is subjected to surface acid treatment, a specific amount of the following surface treatment agent is applied and adhered to the oxidized surface, and the surface treatment is performed.

[0030] The surface treatment agent used in the present invention is mainly composed of at least one compound of a sulfonic acid compound, a polyol, or a polycarbonate compound, and one or two of these compounds The above is used.

Examples of the sulfonic acid compounds include ligne sulfonic acid compounds, naphthalene sulfonic acid formalin condensates, melamine sulfonic acid formalin condensates, anthracene sulfonic acid formalin condensates, and aromatic amino sulfonic acid compounds.

[0031] Examples of polyols include neopentyl glycol, pentaerythritol, neopentyl darlicol hydroxyhydroxyphosphate or derivatives thereof, hexanediol or pentanediol.

[0032] Polycarboxylic acid compounds include styrene maleic anhydride copolymers and partially esterified products thereof, aryl ether maleic anhydride copolymers and derivatives thereof, vinyl ether maleic anhydride copolymers and derivatives thereof, ( (Branched) pentyl ether maleic anhydride copolymer and derivatives thereof, (meth) acrylic acid (meth) acrylic acid ester copolymers and derivatives thereof.

[0033] Among these, combined use of a lignite sulfonic acid compound and a polyol is preferred, even though a lignite sulfonic acid compound and a polyol are preferred.

Specifically, as these surface treatment agents, water-reducing agents and high-performance water-reducing agents used for the purpose of imparting high fluidity to ready-mixed concrete, for example, water-reducing agents from the Phenoris series of NEMBEE, Leo Build SP series of high-performance water reducing agents and the like can be mentioned, and these can be suitably used as the surface treatment agent of the present invention.

[0034] The method of attaching the surface treatment agent to the polypropylene fiber is generally performed by a method of applying the surface treatment agent to the polypropylene fiber. As this coating method, Dip coating method (dipping method) in which polypropylene fiber is dipped in surface treatment solution, spray coating method in which surface treatment solution is sprayed onto polypropylene fiber, and applied to polypropylene fiber using brush coating or roll coater Examples thereof include a method of applying a surface treating agent solution, a knot dry method and the like, and among these, a dip coating method is preferable.

[0035] The surface treatment agent is applied to the polypropylene fiber and then dried. The drying temperature is usually 10 ° C or higher, preferably 20 to 90 ° C, more preferably 30 to 90 ° C. It is a range. When the drying temperature is 30 to 90 ° C., it is preferable because the wet tension increases, the adhesion to the cement increases, and the bending toughness coefficient and bending toughness increase.

[0036] The amount of the surface treatment agent attached to the polypropylene fiber is 0.1 to 5% by weight, preferably 0.5 to 5% by weight, based on the total fiber. If the adhesion amount is less than 0.1% by weight with respect to the total fiber, the polypropylene fiber is not sufficiently hydrophilic, and the bending strength and bending toughness of the cement molded body are insufficiently improved. The effect of imparting hydrophilicity is not further improved, and therefore, the bending strength and bending toughness of the cement molded body reach an equilibrium, and conversely the cost increases.

[0037] The polypropylene fiber subjected to the surface treatment in this manner is cut into a predetermined length and becomes a short fiber for cement reinforcement. The length of the short fiber is 5 to 100 mm, preferably 20 to 70 mm. If the fiber length is less than 5 mm, the cement will come off, and if it exceeds 100 mm, the dispersibility will be poor.

[0038] The polypropylene fiber for cement reinforcement of the present invention is used as a reinforcing fiber material by blending with cement, fine aggregate, coarse aggregate, water and an appropriate amount of concrete admixture. Here, examples of the cement include hydraulic cements such as Portland cement, blast furnace cement, silica cement, fly ash cement, white Portland cement, and alumina cement, and cements such as plaster, air-hardening cement such as lime, and the like. Examples of fine aggregates include river sand, sea sand, mountain sand, crushed sand, quartz sand, glass sand, iron sand, ash sand, and other artificial sand.Coarse aggregates include reki, gravel, crushed stone, slag, and various artificial sands. A typical example is lightweight aggregate.

[0039] cement reinforcing polypropylene fiber spraying construction for use if the concrete of the present invention, the amount is, cement, fine aggregate, coarse aggregate, the concrete mixture lm ³ consisting of water, etc. On the other hand, it is important to mix and disperse 4 to 19 kg, preferably 6 to 14 kg of polypropylene fiber. This is because even if the blended amount of polypropylene fiber exceeds 19 kg, the fiber does not distribute evenly in the concrete, so the bending toughness does not increase. Small post-reinforcing effect.

[0040] Further, as a mixing method in this case, a concrete mixture made of cement, fine aggregate, coarse aggregate, water or the like is added to form base concrete, and after mixing this base concrete, polypropylene fiber is mixed. It is preferable to add and knead. The mixing time is the power by the amount of mixing per time. Generally, mixing of base concrete is 45 to 90 seconds, mixing polypropylene fiber after mixing. Even the range of 45 to 90 seconds is appropriate.

[0041] In the construction of shotcrete, when the polypropylene fiber of the present invention is used in the above blending amount, it is preferable to adjust the slump range to 8 to 21 cm. This is preferable because the slump is less than 8 cm, and the spraying work becomes difficult, and when it exceeds 21 cm, the rebound becomes large! /. It is effective that the spray nozzle for constructing spray concrete in such a slump range should be arranged at right angles to the spray surface and the distance between the nozzle and the spray surface should be 0.5 to 1.5 m. It becomes.

[0042] Example 1

(1) Manufacturing of fiber

Polypropylene (MFR = 4.0g / 10min, Tm = 163 ° C) is charged into an extruder, spun from a circular nozzle, cooled, and then hot-air oven drawing method, hot drawing temperature 115 ° C, heat relaxation temperature 1 Stretch at 20 ° C, draw ratio 7-8 times to form a monofilament with a fineness of 4300 dt, and then change the embossing-up pressure using an embossed roll with hard lattice pattern and a hard rubber roll to change the average flatness Polypropylene monofilaments having irregularities on the surfaces with different rates were obtained. The wetting tension of the obtained monofilament surface was 32 mNZm.

This polypropylene monofilament was subjected to corona discharge treatment at 30 W'min per lm ^{2 of} polypropylene monofilament surface as surface acid treatment, and the wetting tension of the obtained monofilament surface was 45 mNZm.

Furthermore, the polypropylene monofilament is immersed in a treatment solution (Polylith No. 70, manufactured by ENUMB Co., Ltd.) consisting of a lignosulfonic acid compound and a polyol composite as a surface treatment agent. After the pickling treatment, it was dried at 20 ° C to adhere 1% by weight of the surface treatment solution. The polypropylene monofilament was cut to a fiber length of 48 mm to obtain polypropylene fiber.

[0043] (2) Evaluation test 1

After removing the surface treatment liquid adhering to the polypropylene fiber by washing with the polypropylene fiber obtained above, the wetting tension was measured according to JIS K 6768 (1999), and the result was displayed. Shown in 1.

[0044] (3) Evaluation test 2

The polypropylene fiber obtained above was subjected to a fiber adhesion test by the following method, and the results are shown in Table 2. The specimen preparation method and loading test method were in accordance with the Japan Concrete Engineering Association “JCI-SF8 Fiber Adhesion Test Method”.

1) Fiber embedding conditions

Embedding length: 23.75 (mm)

Partition plate thickness: 0.5 (mm)

Fixing length: 23.75 (mm)

Fiber length: 48 (mm)

[0045] 2) Materials used and blending conditions

Cement: Early strong Portland cement (Density = 3.13g / cm ³ )

Fine aggregate: Toyoura standard sand (surface dry density = 2.64 g / cm ³ )

Water: tap water

Water cement ratio: 50%

Cement sand ratio: 1: 1.7

Fiber: Polypropylene fiber was used which was stored for 180 days at room temperature after the surface treatment agent was applied and dried.

Curing was carried out at 20 ° C under water for 14 days.

[0046] (4) Evaluation test 3

The polypropylene fiber obtained above was tested for concrete reinforcement effect by the following method, and the results are shown in Table 3.

1) Materials used and blending conditions Cement: Ordinary Portland cement (Density = 3.15g / cm ³ ) 340kg / m ³

Fine aggregate: Kisarazu mountain sand (surface dry density = 2.60 g / cm ³ ) 894 kg / m ³

Coarse aggregate: Ome crushed stone 1505 (surface dry density = 2.65 g / cm ³ ) 880 kg / m ³

Water: Tap water 170kg / m ³

Admixture: High-performance AE water reducing agent ENEBBY Rheobuild SP8SB 4.42kg / m ³ Fiber: Polypropylene fiber is a volume that is stored for 180 days at room temperature after it has been surface-treated and dried. As a result, 0.3% was blended.

[0047] 2) Mixing concrete

Use a forced biaxial kneading mixer with a capacity of 100 liters, and perform one batch at 60 liters. The temperature when kneading the concrete was about 20 ° C. Kneading is performed by adding coarse aggregate, fine aggregate and cement for 30 seconds, then adding water and admixture, mixing for 120 seconds, adding reinforcing fibers and mixing for 60 seconds. Mix and drain.

[0048] 3) Specimen creation

It conformed to the Japan Society of Civil Engineers standard “How to make specimens for strength and toughness testing of steel fiber reinforced concrete” (OSCE F552-1983). The specimens were demolded after 24 hours, and water curing was performed until the age of 28 days.

[0049] 4) Test method

Japan Society of Civil Engineers standard "Bending strength and bending toughness test method of steel fiber reinforced concrete" (

JSCE G552-1983).

[0050] Example 2

In Example 1, the obtained polypropylene monofilament was subjected to corona discharge treatment, followed by the same treatment except that a surface treatment agent was adhered and dried at 60 ° C. for 4 hours. The results are shown in Tables 1 to 3.

[0051] Example 3

In Example 1, plasma treatment was performed on the surface of the obtained polypropylene monofilament at 2.5 kW in a two-stage treatment, and then a surface treatment agent was attached and dried at 60 ° C for 4 hours. The procedure was the same except for the above. The results are shown in Tables 1 to 3.

[0052] Example 4 In Example 1, plasma treatment was performed on the surface of the obtained polypropylene monofilament in a two-step treatment at 2.5 kW, and then a surface treatment agent was adhered and dried at 20 ° C. The same was done. The results are shown in Tables 1 to 3.

[0053] Comparative Example 1

In Example 1, the same procedure was performed except that the obtained polypropylene monofilament was not subjected to corona discharge treatment and adhesion of the surface treatment agent at all. The results are shown in Tables 1 to 3.

[0054] Comparative Example 2

In Example 1, the same procedure was performed except that the surface treatment agent was not adhered to the polypropylene monofilament obtained by corona discharge treatment. The results are shown in Tables 1 to 3.

[0055] Comparative Example 3

In Example 1, plasma treatment was performed on the surface of the obtained polypropylene monofilament in the same manner except that the surface treatment agent was not adhered after performing a two-step treatment at 2.5 kW. . The results are shown in Tables 1 to 3.

[0056] As is clear from Table 1, the wetting tension of polypropylene fibers coated with a surface treatment solution after surface oxidation treatment did not decrease even after 1 year, especially at a high temperature of 30 to 90 ° C. It was found that the wet tension increased in the dried product.

As is clear from Table 2, the polypropylene fiber cement was treated with a surface treatment solution and then dried by applying a surface treatment solution, compared to the one without the surface treatment solution. It was found that the adhesive strength to was high.

Furthermore, as is clear from Table 3, the toughness coefficient of the polypropylene fiber after the surface acid treatment was applied and the surface treatment solution was applied and dried, compared to the case where the surface treatment solution was not applied. Also, the bending toughness was high.

[0057] [Table 1] Wetting tension (mN / m)

0 曰 1 曰 7 0 30 曰 90 曰 180 days 365 days Example 1 46 46 45 45 45 45 45 Example λ '46 60 65 65 65 65 65 Example 3 62 65 70 70 70 70 70 Example 4 62 62 60 60 60 60 60 Comparative Example 1 32 32 32 32 32 32 32 Comparative Example 2 45 45 43 41 39 36 35 Comparative Example 3 60 56 52 50 50 48 48

Pull-out start load per fiber (N) Maximum pull-out load (N) Example 1 50.7 157.6 Example 2 52.9 169.2 Example 3 53.9 172.7 Example 4 52.7 165.6 Comparative Example 1 47.4 147.1 Comparison Example 2 48.3 148.8 Comparative Example 3 50.9 158.0

Bending strength Bending toughness Bending toughness factor

(N / mm ² ) (N mm) (N / mm ² ) Example 1 4.90 42000 1.87 Example 2 4.91 51200 2.28 Example 3 4.91 56200 2.49 Example 4 4.90 48200 2.14 Comparative Example 1 4.78 34000 1.51 Comparative Example 2 4.85 38400 1.71 Comparative Example 3 4.84 43800 1.94

Claims

The scope of the claims

[1] The surface of a drawn yarn made of thermoplastic resin fibers is subjected to surface oxidation treatment, and the surface thereof has a sulfonic acid compound, polyols, and polycarboxylic acid compound strength. At least one selected A thermoplastic resin fiber for cement reinforcement characterized by comprising 0.1 to 5% by weight of the above compound.

[2] A surface oxidation treatment is applied to the surface of the drawn yarn made of thermoplastic resin fiber, and the surface of the sulfonic acid compound, polyol, and polycarboxylic acid compound is selected. 2. The thermoplastic resin fiber for cement reinforcement according to claim 1, wherein 0.1 to 5% by weight of the above compound is applied, and dried and adhered at 20 to 90 ° C.

[3] The thermoplastic resin for cement reinforcement according to claim 1 or 2, wherein the drawn yarn composed of a thermoplastic resin fiber fiber is a flat yarn obtained by slitting and drawing a thermoplastic resin film. Absorbent fiber.

[4] The thermoplastic resin fiber for cement reinforcement according to [1] or [2], wherein the drawn yarn comprising the thermoplastic resin fiber is a filament obtained by spinning a thermoplastic resin.

[5] The thermoplastic resin fiber for cement reinforcement according to any one of claims 1 to 4, wherein the thermoplastic resin fiber is a polypropylene-based resin fiber.

[6] The single-filament fineness is 200 to 10,000 dt or more with irregularities formed in the range of the average flatness ratio power l. A flat yarn or monofilament, and the surface of the fiber is subjected to a surface oxidation treatment so that the wetting tension of the fiber surface is 40 mN / m or more. The thermoplastic resin fiber for cement reinforcement according to any one of the above.

[7] Strength of sulfonic acid compounds Lignone sulfonic acid compounds, naphthalene sulfonic acid formalin condensate, melamine sulfonic acid formalin condensate, anthracene sulfonic acid formalin condensate, aromatic amino sulfonic acid compound, methane sulfonic acid compound And a benzene sulfonic acid-based compound strength. The cement-reinforced thermoplastic resin fiber according to any one of claims 1 to 6, which is at least one selected compound.

[8] Polyols are neopentyl glycol, pentaerythritol, hydroxybivalin The thermoplastic cocoon for cement reinforcement according to any one of claims 1 to 6, which is at least one compound selected from acid neopentyl glycol or derivatives thereof, hexanediol and pentanediol. Fat fiber.

Polycarboxylic acid compound strength Styrene Maleic anhydride copolymer and its partially esterified product, allyl ether Maleic anhydride copolymer and its derivative, Bue ether Maleic anhydride copolymer and its derivative, (Branched) pentyl ether Maleic anhydride copolymer and derivatives thereof, (meth) acrylic acid (meth) acrylic acid ester copolymer and derivatives thereof At least one compound selected from claims 1 to claims Item 7. The thermoplastic resin fiber for cement reinforcement according to any one of Items 6