KR101861038B1 - Manufacturing method for blend fiber of polyvinylalcohol/acrylate polymer blend, blend fiber thereby and fiber product using the same - Google Patents

Abstract

The present invention relates to a method for producing polyvinyl alcohol/acrylic polymer blend fiber and polyvinyl alcohol/acrylic polymer blend fiber and a textile product including the blend fiber produced therefrom. The method of producing polyvinyl alcohol/acrylic polymer blend fiber comprises: a step of spinning a dope solution in which a vinyl ester polymer and an acrylic polymer are dissolved in a dope solvent and obtaining precursor fiber; and a step of non-uniformly saponifying the obtained precursor fiber and converting the vinyl ester polymer to polyvinyl alcohol. According to the production method of the present invention, it is able to produce blend fiber, in which hydrophilic polyvinyl alcohol and hydrophobic acrylic polymer as incompatible polymeric materials are mixed without phase separation, without using a compatibilizer.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a process for producing a polyvinyl alcohol / acrylic polymer blend fiber, a blend fiber and a fiber product produced therefrom, and a blend fiber /

The present invention relates to a process for producing a polyvinyl alcohol / acrylic polymer blend fiber, a blend fiber and a fiber product produced therefrom, and more particularly to a blend fiber obtained by spinning a blend solution obtained by dissolving a vinyl ester polymer and an acrylic polymer in a solvent There is provided a method for producing polyvinyl alcohol / acrylic polymer blend fibers in which hydrophilic polyvinyl alcohol and a hydrophobic acrylic polymer are mixed without phase separation as non-flammable polymer materials without using a compatibilizing agent by making the precursor fibers nonuniformly saponificated, To blend fibers and textile products to be produced.

Polyvinyl alcohol fiber is a representative alternative asbestos substitute organic fiber used for FRC (fiber reinforced cement) together with high strength acrylic fiber. Because it has irregular cross section, wrinkles on the surface and hydroxyl group, it has excellent affinity with cement particles and is the most suitable fiber for FRC substituting for asbestos. High strength polyvinyl alcohol fibers are used not only for replacing asbestos but also for replacing reinforcing bars. Since polyvinyl alcohol fiber is lighter than rebar and has excellent durability and has very high tensile strength and elastic modulus, it is a technology to use FRP reinforcement in the form of reinforcing bar reinforced with polyvinyl alcohol filament, It is known. In addition to high strength and high elasticity, it has no corrosion and excellent chemical resistance, and is used as a substitute for reinforcing steel in structures requiring high durability in areas such as seawater and water or marine structures.

The polymer blend is a mixture of two or more kinds of polymers, and is advantageous in that it is much less expensive than the modification by the copolymerization method as a means of modifying the physical properties of a polymer by blending. Also, in the case of a compatible polymer blend, the physical and chemical performance of the polymer blend may be superior to that of the polymer blend due to the synergistic effect of the physical and chemical performance among the polymer blend. However, if there is no strong intermolecular attraction between the constituent polymers, most of the polymer blends are incompatible, resulting in a heterogeneous mixture. The low interfacial adhesion between the constituent polymers is a major cause of the low mechanical performance of the heterogeneous polymer blend. Since the polyvinyl alcohol as the hydrophilic polymer and the acrylic polymer as the hydrophobic polymer are incompatible with each other, blending is difficult because it is difficult to find a single solvent capable of dissolving the two polymers. Thus, a compatibilizer that increases the compatibility of a blend using a graft or block copolymer may be used, or a blend of two or more solvents may be used.

The present inventors have made intensive studies on a technique for producing polyvinyl alcohol as a hydrophilic polymer and an acrylic polymer blend fiber as a hydrophobic polymer and have found that a polyvinyl acetate which is a precursor of polyvinyl alcohol and an acrylic polymer as a hydrophobic polymer are blended Polymer blend fibers were prepared by wet spinning and ultrafast centrifugal spinning, and then -OCOCH ₃ was converted into -OH in a polyvinyl acetate / acrylic polymer blend fiber by a nonuniform saponification process to obtain polyvinyl alcohol / Acryl-based polymer blend fibers. The present invention has been completed based on this finding.

An object of the present invention is to provide a process for producing a polyvinyl alcohol / acrylic polymer blend fiber capable of solving the problem of compatibility between a hydrophilic polyvinyl alcohol and a hydrophobic acrylic polymer without using a compatibilizing agent or a mixed solvent .

Another object of the present invention is to provide a polyvinyl alcohol / acrylic polymer blend fiber produced using the above method.

It is a further object of the present invention to provide a fiber product comprising said polyvinyl alcohol / acrylic polymer blend fibers.

It is a further object of the present invention to provide a fiber product comprising said polyvinyl alcohol / acrylic polymer blend fibers.

It is a further object of the present invention to provide a fiber-reinforced cement composite material comprising the polyvinyl alcohol / acrylic polymer blend fibers.

According to the present invention, there is provided a method for producing a precursor fiber, comprising: spinning a dope solution in which a vinyl ester polymer and an acrylic polymer are dissolved in a dope solvent to obtain precursor fibers; And converting the vinyl ester polymer into polyvinyl alcohol by non-uniformly saponifying the obtained precursor fiber to obtain a polyvinyl alcohol / acrylic polymer blend fiber.

In one embodiment, the vinyl ester-based polymer may be polyvinyl acetate.

In one embodiment, the dope solvent may be at least one selected from the group consisting of benzene, toluene, ethanol, butanol, methyl ethyl ketone, ethyl acetate, chloroform and dimethylformamide.

In one embodiment, the total content of the vinyl ester-based polymer and the acrylic polymer in the dope solution may be 1 to 30 wt%.

In one embodiment, the content ratio of the vinyl ester polymer and the acrylic polymer dissolved in the dope solution may be 1:99 to 99: 1 (w / w) of the vinyl ester polymer: acrylic polymer.

In one embodiment, the spinning of the dope solution may be carried out using wet spinning or ultra-high speed centrifugation.

In one embodiment, the coagulating solution may be water, glycerin, butyl alcohol, xylenes, glycols, or mixtures thereof when performing the wet spinning.

In one embodiment, the heterogeneous saponification is performed by impregnating polyvinyl acetate / acrylic polymer blend fibers into a mixed solution which is an alkaline solution comprising a dispersant and a swelling agent.

In one embodiment, the dispersant may be at least one selected from the group consisting of sodium sulfate, sodium sulfite, calcium sulfate, and magnesium sulfate.

In one embodiment, the swelling agent may be at least one selected from the group consisting of methanol, ethanol, propanol, ethylene glycol, propylene glycol, tetrahydrofuran (THF), dimethylsulfoxide (DMSO), benzene and acetone.

In one embodiment, the heterogeneous saponification is carried out at a temperature ranging from 5 [deg.] C to 70 [deg.] C for 2 to 100 hours.

Further, the present invention provides a polyvinyl alcohol / acrylic polymer blend fiber produced by the above-described method.

The present invention also provides a fiber product comprising the polyvinyl alcohol / acrylic polymer blend fiber. In one embodiment, the fiber product can be a filament, staple fiber, yarn, nonwoven fabric or woven fabrics.

According to the production method of the present invention, hydrophilic polyvinyl alcohols and hydrophobic acrylic polymers can be blended fibers without phase separation without using a compatibilizing agent.

The polyvinyl alcohol / acrylic polymer of high molecular weight can be produced by the production method of the present invention, and the blend fiber can be applied as a reinforcing material used for cement, concrete, and the like.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram illustrating a method for producing a polyvinyl alcohol / acrylic polymer brand fiber according to the present invention.
2 is a photomicrograph of a polyvinyl alcohol / acrylic polymer brand fiber produced according to the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a block diagram illustrating a method of making blended fibers according to the present invention. The production method of the present invention includes a step (S1) of obtaining precursor fibers and a step (S2) of non-uniform saponification of the obtained precursor fibers to convert the vinyl ester-based polymer in the blended fibers into polyvinyl alcohol.

1. Obtaining Precursor Solution (S1)

In the first step of the production process of the present invention, a precursor fiber is obtained by spinning a dope solution in which a vinyl ester polymer and an acrylic polymer are dissolved in a dope solvent.

In the present invention, the vinyl ester-based polymer as the first component dissolved in the dope solution is represented by the following formula (1), and refers to a polymer containing a vinyl ester as a repeating unit:

[Chemical Formula 1]

Wherein R is H or C1 to C20 linear or branched alkyl; and n is an integer of 10 to 10,000.

The polymer is obtained by polymerizing a vinyl ester monomer. In the embodiment of the present invention, the vinyl ester monomer is not particularly limited, and examples thereof include vinyl formate, vinyl acetate, vinyl propionate, vinyl caprylate, vinyl laurate , Vinyl stearate, vinyl benzoate, vinyl pivalate, vinyl versatate and the like can be used. Preferably, vinyl acetate is used.

The copolymerizable monomer may be added during the polymerization of the vinyl ester monomer. Examples of the copolymerizable monomer include an? -Olefin-based monomer such as ethylene, propylene, n-butene, or isobutylene; Acrylic acid and its salts; Propyl acrylate, n-butyl acrylate, i-butyl acrylate, t-butyl acrylate, 2-ethylhexyl acrylate, dodecyl acrylate, Alkyl acrylate monomers such as octadecyl acrylate; Methacrylates and their salts; Methyl methacrylate, ethyl ethacrylate, n-propyl methacrylate, i-propyl methacrylate, n-butyl methacrylate, i-butyl methacrylate, t-butyl methacrylate, Alkyl methacrylate monomers such as methacrylate, dodecyl methacrylate and octadecyl methacrylate; Acrylamide, n-methylacrylamide, N-ethyl acrylamide, N, N'-dimethyl acrylamide, diacetone acrylamide, acrylamide propanesulfonic acid and salts thereof, acrylamidopropyldimethylamine and its salts or quaternary salts thereof , Acrylamide derivatives such as N-methylol acrylamide and derivatives thereof; Unsaturated dicarboxylic acids such as itaconic acid and fumaric acid, and salts or esters thereof; And vinylsilyl-based monomers such as vinyltrimethoxysilane, but are not limited thereto. The content of these copolymerizable monomers is usually 20 mol% or less.

The acrylic polymer as the second component to be dissolved in the blend solution is represented by the following formula (2), and refers to a polymer containing acrylate as a repeating unit:

(2)

Wherein R 'is hydrogen or methyl; R " is C1 to C20 linear or branched alkyl; and m is an integer of 10 to 10,000.

In one embodiment, the acrylic polymer may be a poly (meth) acrylate-based polymer. In a preferred embodiment, the poly (meth) acrylate-based polymer is selected from, for example, polymethylacrylate, polyethyl acrylate, polypropyl acrylate, polyisopropyl acrylate, poly (n-butyl acrylate) (butyl acrylate), poly (isobutyl acrylate), polyisobutyl acrylate, poly (tert-butyl acrylate), polycyclohexyl acrylate, poly (methyl methacrylate) Methacrylate), poly (n-decyl methacrylate), poly (n-hexadecyl methacrylate), polyacrylamide, or a mixture or copolymer of two or more thereof.

In another embodiment, the poly (meth) acrylate-based polymer may be one copolymerized with an ethylenic comonomer such as ethylene, acrylonitrile, butadiene, styrene, vinylidene chloride, vinyl chloride, vinyl acetate or the like. The poly (meth) acrylate polymer co-polymerized with the ethylenic comonomer may be, for example, poly (ethylene-co-ethyl acrylate), poly (ethylene-co-acrylic acid), poly (acrylonitrile- Methacrylate), poly (styrene-co-methyl acrylate), poly (vinyl chloride-co-methyl acrylate), poly , Poly (vinylidene chloride-co-methylacrylate), poly (vinyl acetate-co-methyl acrylate), poly (acrylonitrile-co-ethyl acrylate) Ethyl acrylate), poly (vinyl chloride-co-ethyl acrylate), poly (vinyl chloride-co-ethyl acrylate) Poly (vinyl acetate-co-ethyl acrylate (Acrylonitrile-co-butyl acrylate), poly (butadiene-co-butyl acrylate), poly (methyl methacrylate-co-butyl acrylate) ), Poly (vinyl chloride-co-butyl acrylate), poly (vinylidene chloride-co-butyl acrylate), poly (vinyl acetate-co-butyl acrylate) and the like.

In the present invention, the vinyl ester polymer and the acrylic polymer can be prepared by bulk polymerization, solution polymerization, emulsion polymerization or suspension polymerization. Particularly, bulk polymerization is advantageous in that relatively high molecular weight vinyl ester polymer and acrylic polymer can be obtained because the probability of chain transfer is low as compared with other polymerization methods because monomer alone exists in the polymerization system.

In the production process of the present invention, the above-mentioned vinyl ester polymer and acrylic polymer are dissolved in a dope solvent to prepare a blend solution. The dope solvent may be used without limitation as long as it is a solvent that dissolves both the vinyl ester polymer and the acrylic polymer.

In one embodiment, the dope solvent is benzene, toluene, ethanol, xylene, butanol, methyl ethyl ketone, ethyl acetate, chloroform, DMF or a mixture of two or more thereof.

In the dope solution, the total content of the vinyl ester polymer and the acrylic polymer is preferably 1 to 30 wt%, and more preferably 6 wt% to 15 wt%, based on the total weight of the blend solution. When the concentration is less than 1 wt%, the solution is too thin to easily form fibers, and when it is more than 30 wt%, spinning is difficult due to high viscosity.

On the other hand, the blend ratio of the vinyl ester polymer to the acrylic polymer in the dope solution is such that the content ratio of the vinyl ester polymer to the acrylic polymer is in the range of 1:99 to 99: 1 (w / w) of the vinyl ester polymer: acrylic polymer . ≪ / RTI >

In the production method of the present invention, the dope solution is prepared by dissolving the dope solution in a vinyl ester-based polymer and an acrylic polymer in a dope solvent. After dissolving the polymer components, the solution may be allowed to dry, for example, at a temperature of 20 ° C to 35 ° C, for example, for 0.5 to 5 hours, in order to stabilize the dope solution. Preferably at a temperature of about < RTI ID = 0.0 > 20 C. < / RTI >

By spinning the dope solution using wet spinning or ultrafast centrifugal spinning, precursor fibers are formed which are formed from a blend of vinyl ester polymer and acrylic polymer.

Applicable to the production method of the polyvinyl alcohol / acrylic polymer blend fiber of the present invention, the wet spinning is performed by dissolving the polymer in a solvent, then extruding it from the spinneret into a coagulating solution, solidifying it by chemical reaction or dehydration, . In the subsequent steps, the mechanical properties of the fibers can be improved by orienting the polymer chains in the fiber direction by stretching and stretching. The continuous wet spinning method has a drawback in that it needs to be subjected to post-treatment such as washing, dehydrating and drying, but it has an advantage that productivity can be improved by making a lot of spinnerets.

In the wet spinning method, the polymer solution is discharged through the spinneret into the coagulating solution. The wet process is roughly classified into phase separation and gelation. The phase separation process separates the polymer-rich phase and the polymer-lean phase by replacing the solvent and the permeable non-solvent in the coagulation solution in which the solvent and water are mixed. Is a method of forming an intermolecular bond of a polymer in a solution by a change in temperature or concentration by using a coagulating solution of a non-permeable solvent such as pure solvent or polyethylene glycol. Both the phase separation method and the gelation method are applicable in the present invention. In addition, the immersion method in which the spinneret is immersed in the coagulating solution and the spinning solution is discharged in the coagulating solution and the spinneret are positioned at a certain distance from the surface of the coagulating bath, and the spinning solution is discharged into air or an inert gas layer There are two types of dry-jet wet spinning, and any of them can be applied to the production method of the present invention. In the case of the dipping method, it is difficult to increase the elongation rate because the spinning liquid immediately coagulates after contact with the coagulating liquid after discharging. On the other hand, since the spinning liquid is not solidified in the air layer in the wet spinning method, it is advantageous to give a high elongation.

In one embodiment of the production method of the present invention, water, glycerin, butyl alcohol, xylene, glycol, or a mixture thereof may be used as the coagulating solution in the application of the wet spinning.

In one embodiment, the polymer blend solution may be extruded from the spinneret into a coagulating solution while maintaining the temperature of the coagulating solution filled in the coagulation bath at about 30 to 50 DEG C, and then solidified through dehydration to produce a fiber form.

Another method that can be applied to obtain precursor fibers in the first step of the process of the present invention is centrifugal spinning. Centrifugal spinning is a method of producing micron fibers or nanofibers by high-speed centrifugal force generated by the spinning disk rotating. Centrifugal spinning is a system for making cotton candy with sugar, that is, a polymer melt or a solution is ejected at a high centrifugal force to form fibers. The centrifugal spinning method uses a high-speed centrifugal force by a motor rotation to form a Taylor cone when the spinning liquid is ejected through the spinneret. When the centrifugal force overcomes the surface tension, the spinning jet is rapidly ejected and a liquid jet And the ejected jet is a technique for producing fibers while undergoing a stretching and solidification process by a composite action such as centrifugal force and air resistance.

2. Unevenness Saponification (S2)

In the second step of the production process according to the present invention, the precursor fibers are nonuniformly saponified, and the vinyl ester polymer is converted into polyvinyl alcohol, whereby polyvinyl alcohol / acrylic polymer blend fibers are produced.

Generally, when polyvinyl alcohol is produced, uniform saponification refers to a process in which a precursor for producing polyvinyl alcohol is dissolved in a solvent, and then an alkali or an aqueous acid solution is added thereto to obtain polyvinyl alcohol through a hydrolysis reaction It says. The hydrolysis reaction is called a homogeneous saponification reaction because the state of the system occurs between the solution and the solution. The heterogeneous saponification, which is differentiated from this, is a state in which the precursor of the polyvinyl alcohol is in a state other than liquid, Is a liquid phase, so it is called nonuniform saponification. Particularly, since the nonuniform saponification is a solid phase, the hydrolysis reaction proceeds from the surface and is also called surface saponification.

In the present invention, heterogeneous saponification is a process for producing polyvinyl alcohol by reacting a vinyl ester polymer, which is a precursor of polyvinyl alcohol as a solid phase, with an aqueous alkali or acid aqueous solution by controlling the temperature, the concentration of the aqueous solution,

Acrylic polymers (for example, PMMA) are resistant to organic solvents, bases, acids and alcohols, so that the hydrolysis reaction hardly takes place, and extremely small hydrolysis reactions occur even when they occur.

In the present invention, polyvinyl alcohol / acrylic polymer blend fibers are obtained by converting an ester group such as -OCOCH ₃ group of a vinyl ester polymer into an -OH group by the above-mentioned heterogeneous saponification.

In one embodiment of the present invention, the heterogeneous saponification is performed by impregnating an acid mixed solution or an alkali mixed solution containing a dispersant and a swelling agent with polyvinyl acetate / acrylic polymer blend fibers.

The acid mixture solution for the heterogeneous saponification may be hydrochloric acid, nitric acid, or a mixture thereof. In addition, the alkali mixed solution for saponification may be sodium chloride, sodium hydroxide, potassium hydroxide, or a mixture thereof.

The dispersing agent may be sodium sulfate, sodium sulfite, calcium sulfate, magnesium sulfate, or a mixture thereof.

The swelling agent may be methanol, ethanol, propanol, ethylene glycol, propylene glycol, tetrahydrofuran (THF), dimethylsulfoxide (DMSO), benzene, acetone, or a mixture thereof. Preferably, methanol can be used which is easy to obtain, low in cost, low in boiling point, and easy to handle.

In one embodiment, the acid mixture solution comprises hydrochloric acid, nitric acid, or mixtures thereof; A dispersing agent selected from sodium sulfate, sodium sulfite, calcium sulfate, magnesium sulfate or a mixture thereof; Any one of swelling agents selected from methanol, ethanol, propanol, ethylene glycol, propylene glycol, tetrahydrofuran (THF), dimethylsulfoxide (DMSO), benzene, acetone or mixtures thereof; And an acid solution in which water, preferably distilled water, is mixed and dissolved may be used, but the present invention is not limited thereto.

In a specific embodiment, the acid mixture solution comprises 1 g to 30 g of hydrochloric acid, nitric acid, or a mixture thereof per gram of the precursor fiber, and any one selected from sodium sulfate, sodium sulfite, calcium sulfate, magnesium sulfate, 1 to 30 g of a dispersing agent selected from the group consisting of methanol, ethanol, propanol, ethylene glycol, propylene glycol, tetrahydrofuran (THF), dimethylsulfoxide (DMSO), benzene, acetone, 1 to 30 g, and an aqueous solution of 10 to 500 ml.

In another embodiment, the alkali mixed solution comprises sodium chloride, sodium hydroxide, potassium hydroxide, or a mixture thereof; A dispersing agent selected from sodium sulfate, sodium sulfite, calcium sulfate, magnesium sulfate or a mixture thereof; Any one of swelling agents selected from methanol, ethanol, propanol, ethylene glycol, propylene glycol, tetrahydrofuran (THF), dimethylsulfoxide (DMSO), benzene, acetone or mixtures thereof; And a second solvent in which water, preferably distilled water, is mixed and dissolved can be used, but the present invention is not limited thereto.

In a specific embodiment, the alkali mixed solution is prepared by mixing 1 to 30 g of sodium chloride, sodium hydroxide, potassium hydroxide or a mixture thereof in the presence of a dispersant selected from sodium sulfate, sodium sulfite, calcium sulfate, magnesium sulfate, 1 to 30 g of any one swelling agent selected from methanol, ethanol, propanol, ethylene glycol, propylene glycol, tetrahydrofuran (THF), dimethylsulfoxide (DMSO), benzene, acetone, g, and 10 to 500 ml of an aqueous solution are mixed and dissolved.

In one embodiment, the heterogeneous saponification may be performed by introducing the precursor fibers into an acid mixed solution or an alkali mixed solution at a temperature of 5 DEG C to 70 DEG C for 2 to 100 hours. Preferably at a temperature of 10 [deg.] C to 30 [deg.] C for 6 to 48 hours. The saponification is carried out at a temperature ranging from 5 ° C to 70 ° C in order to maximize the activation of the swelling agent serving as a catalyst.

The saponification degree of the vinyl ester polymer / acrylic polymer blend fiber produced by the present invention is preferably 50% to 99.99%. Here, the " degree of saponification " indicates the proportion of units actually saponified as vinyl alcohol units among the units obtained by conversion to vinyl alcohol units by saponification. Specifically, -COCH ₃ And the number of moles of the compound converted to -OH with respect to the number of moles of the compound having the ester group.

3. Polyvinyl alcohol / acrylic polymer blend fibers

The polyvinyl alcohol / acrylic polymer blend fibers prepared according to the present invention are obtained by converting the uniformly blended polyvinyl alcohol precursor / acrylic polymer blend fibers into alkali and acid hydrolysing the polyvinyl alcohol precursor into polyvinyl alcohol, And the distribution of the inter-polymer bonding is uniform.

The macroscopic morphology of fibers produced by wet spinning does not have a uniform shape, but microscopic fiber surface morphologies are produced in a smooth morphology. However, in the case of the fiber produced by the present invention, as shown in FIG. 2, a saponification process is performed in a post-treatment process, so that when microscopic morphology is observed, it is possible to obtain an opaque or slightly wrinkled surface.

The strength of the polyvinyl alcohol / acrylic polymer blend fibers produced according to the present invention is superior to that of the fibers (15-20 MPa) spun by PVA alone at 30 MPa, and the polyvinyl alcohol / acrylic polymer blend fibers have a higher strength than polyvinyl alcohol Although there are many -OH groups, it is more hydrophilic than single acrylic fiber.

The polyvinyl alcohol / acrylic polymer blend fiber produced according to the present invention can be produced in the form of a filament or a staple fiber. Further processing can be done in the form of yarns, nonwoven fabrics, woven fabrics and the like.

In addition, the polyvinyl alcohol / acrylic polymer blend fiber produced according to the present invention can be used as a reinforcing material for a high performance fiber-reinforced cement composite material.

Fiber reinforced cement composites are widely used to secure the ductility of cement composites. The interfacial properties between reinforcing fibers and cement composites have an effect on maximizing the effect of reinforcing fibers. Synthetic fibers are widely used to achieve various purposes such as crack control and flexural performance improvement of cement composites. However, synthetic fibers having hydrophobic properties such as polypropylene fibers which are widely used for reinforcing concrete are added to cement composites to decrease adhesion strength with cement matrix, and thus one of important behaviors of fibers in fiber reinforced composites Sufficient fiber resistance can not be secured in the drawing process of the fiber. This result shows that the cement composites can not achieve sufficient performance even after the occurrence of cracks, which is dominated by reinforcing fibers. Therefore, the application of synthetic fibers to a high performance fiber-reinforced cement composite material, which is required to secure a large energy absorption capacity, has been limited. Therefore, in order to apply synthetic fibers as a reinforcing material for cement composite materials, it is necessary to strengthen the interfacial adhesion between the cement composite material and the reinforcing fibers. Therefore, when the polyvinyl alcohol / acrylic polymer blend fiber produced by the present invention is used as a fiber reinforced cement composite material, it has irregular cross-section, wrinkles on the surface, and -OH group to exhibit the interfacial adhesion force and exhibit high strength of the acrylic polymer It is a big advantage because it can do. If the polyvinyl alcohol / acrylic polymer blend fiber of the present invention is used as a fiber reinforced cement composite material, it has irregular cross section, wrinkles on the surface, and -OH group, thereby exhibiting the adhesive strength at the interface and exhibiting high strength of the acrylic polymer.

Since the polyvinyl alcohol / polymethyl methacrylate blend fiber produced according to the present invention has hydrophilic properties, not only the friction resistance is excellent but also the mechanical strength can be improved.

The application as the reinforcing material of the exemplified fiber product or the high performance fiber-reinforced cement composite material is not limited to the present invention, and is merely an example.

Hereinafter, preferred embodiments of the present invention will be described in order to facilitate understanding of the present invention. The following examples are provided to further understand the present invention, but the present invention is not limited by the examples.

Aldrich reagent was used as the starting material and reaction reagent in the compounds used below. All solvents were pure and used without drying or purification.

In the following Production Examples 1 to 4, experiments were conducted to prepare polyvinyl acetate / acrylic polymer blend fibers. A dope solution was prepared by dissolving polyvinyl acetate and a typical polymethyl methacrylate among acrylic polymers in a co-solvent chloroform. The blend ratios of the solutions were adjusted to produce polyvinyl acetate / polymethylmethacrylate blend fibers of various blend ratios.

Preparation Example 1: Preparation of polyvinyl acetate / polymethyl methacrylate blend fiber by wet spinning (blend ratio = 9/1) (w / w)

7 wt.% (9/1) (w / w) of polyvinyl acetate and polymethylmethacrylate was added to the chloroform solvent, and the mixture was stirred at 40 ° C for 30 minutes. The resulting polyvinyl acetate / polymethyl methacrylate blend The solution was stabilized at room temperature for about one hour. The stabilized solution was dipped in the coagulating solution and the spinning solution was discharged in the coagulating solution and solidified to prepare a polyvinyl acetate / polymethylmethacrylate blend fiber.

Preparation Example 2: Preparation of polyvinyl acetate / polymethyl methacrylate blend fiber by wet spinning (blend ratio = 7/3) (w / w)

7 wt.% (7/3) (w / w) of polyvinyl acetate and polymethylmethacrylate was added to the chloroform solvent and stirred at 40 ° C for 30 minutes, and then the resulting polyvinyl acetate / polymethyl methacrylate blend The solution was stabilized at room temperature for about one hour. The stabilized solution was dipped in the coagulating solution and the spinning solution was discharged in the coagulating solution and solidified to prepare a polyvinyl acetate / polymethylmethacrylate blend fiber.

Preparation Example 3: Preparation of polyvinyl acetate / polymethyl methacrylate blend fiber by wet spinning (blend ratio = 5/5) (w / w)

7 wt.% (5/5) (w / w) of polyvinyl acetate and polymethylmethacrylate was added to the chloroform solvent and stirred at 40 ° C for 30 minutes. Then, the resulting polyvinyl acetate / polymethyl methacrylate blend The solution was stabilized at room temperature for about one hour. The stabilized solution was dipped in the coagulating solution and the spinning solution was discharged in the coagulating solution and solidified to prepare a polyvinyl acetate / polymethylmethacrylate blend fiber .

Production Example 4: Preparation of polyvinyl acetate / polymethyl methacrylate blend fiber by wet spinning (blend ratio = 3/7) (w / w)

Polyvinyl acetate and 7 wt.% (3/7) (w / w) of polymethyl methacrylate were added to a chloroform solvent and stirred at 40 ° C for 30 minutes, and then the resulting polyvinyl acetate / polymethyl methacrylate blend The solution was stabilized at room temperature for about one hour. The stabilized solution was dipped in the coagulating solution and the spinning solution was discharged in the coagulating solution and solidified to prepare a polyvinyl acetate / polymethylmethacrylate blend fiber.

Preparation Example 5: Preparation of polyvinyl acetate / polymethyl methacrylate blend fiber by wet spinning (blend ratio = 1/9) (w / w)

7 wt.% (1/9) (w / w) of polyvinyl acetate and polymethylmethacrylate was added to the chloroform solvent and stirred at 40 DEG C for 30 minutes, and then the resulting polyvinyl acetate / polymethyl methacrylate blend The solution was stabilized at room temperature for about one hour. The stabilized solution was dipped in the coagulating solution and the spinning solution was discharged in the coagulating solution and solidified to prepare a polyvinyl acetate / polymethylmethacrylate blend fiber.

In the following Examples 1 to 5, experiments were conducted to prepare polyvinyl alcohol / polymethyl methacrylate blend fibers by saponifying the polyvinyl acetate / polymethyl methacrylate blend fibers prepared in Production Examples. The polyvinyl acetate / polymethylmethacrylate blend fiber prepared in Production Example was saponified using an alkali solution, and then the fiber was stirred in distilled water and then dried at room temperature to obtain polyvinyl alcohol / polymethyl methacrylate Blend fibers were prepared.

Example 1: Preparation of polyvinyl alcohol / polymethyl methacrylate blend fiber by non-uniform saponification of polyvinyl acetate / polymethyl methacrylate blend fibers

100 ml of distilled water, 10 g of NaOH, 10 g of Na ₂ SO _{4 and} 10 g of MeOH were gently agitated for the saponification process of the polyvinyl acetate / polymethyl methacrylate blend fiber (9/1) prepared in Production Example 1 using wet spinning To prepare an alkali solution. The polyvinyl acetate / polymethyl methacrylate blend fiber (1 g) was added to the alkali solution, and the saponification reaction was carried out at 30 ° C for 24 hours. After the saponification reaction, the fibers were washed several times with distilled water, and the washed fibers were dried at room temperature for 12 hours to prepare polyvinyl alcohol / polymethyl methacrylate blend fibers.

Example 2: Preparation of polyvinyl alcohol / polymethyl methacrylate blend fiber by non-uniform saponification of polyvinyl acetate / polymethyl methacrylate blend fibers

100 ml of distilled water, 10 g of NaOH, 10 g of Na ₂ SO _{4 and} 10 g of MeOH were gently agitated for the saponification process of the polyvinyl acetate / polymethyl methacrylate blend fiber (7/3) prepared in Production Example 2 using wet spinning To prepare an alkali solution. The polyvinyl acetate / polymethyl methacrylate blend fiber (1 g) was added to the alkali solution, and the saponification reaction was carried out at 30 ° C for 24 hours. After the saponification reaction, the fibers were washed several times with distilled water, and the washed fibers were dried at room temperature for 12 hours to prepare polyvinyl alcohol / polymethyl methacrylate blend fibers.

Example 3: Preparation of polyvinyl alcohol / polymethyl methacrylate blend fiber by non-uniform saponification of polyvinyl acetate / polymethyl methacrylate blend fibers

100 ml of distilled water, 10 g of NaOH, 10 g of Na ₂ SO _{4 and} 10 g of MeOH were gently agitated for the saponification process of the polyvinyl acetate / polymethyl methacrylate blend fiber (5/5) prepared in Production Example 3 using wet spinning To prepare an alkali solution. The polyvinyl acetate / polymethyl methacrylate blend fiber (1 g) was added to the alkali solution, and the saponification reaction was carried out at 30 ° C for 24 hours. After the saponification reaction, the fibers were washed several times with distilled water, and the washed fibers were dried at room temperature for 12 hours to prepare polyvinyl alcohol / polymethyl methacrylate blend fibers.

Example 4: Preparation of polyvinyl alcohol / polymethyl methacrylate blend fiber by non-uniform saponification of polyvinyl acetate / polymethyl methacrylate blend fiber

100 ml of distilled water, 10 g of NaOH, 10 g of Na ₂ SO _{4 and} 10 g of MeOH were gently agitated for the saponification process of the polyvinyl acetate / polymethyl methacrylate blend fiber (3/7) of Preparation Example 4 prepared using wet spinning Alkali solution was prepared. The polyvinyl acetate / polymethyl methacrylate blend fiber (1 g) was added to the alkali solution, and the saponification reaction was carried out at 30 ° C for 24 hours. After the saponification reaction, the fibers were washed several times with distilled water, and the washed fibers were dried at room temperature for 12 hours to prepare polyvinyl alcohol / polymethyl methacrylate blend fibers.

Example 5: Preparation of polyvinyl alcohol / polymethyl methacrylate blend fibers by non-uniform saponification of polyvinyl acetate / polymethyl methacrylate blend fibers

100 ml of distilled water, 10 g of NaOH, 10 g of Na ₂ SO _{4 and} 10 g of MeOH were gently agitated for the saponification process of the polyvinyl acetate / polymethyl methacrylate blend fiber (1/9) prepared in Production Example 5 using wet spinning To prepare an alkali solution. The polyvinyl acetate / polymethyl methacrylate blend fiber (1 g) was added to the prepared alkali solution, and the saponification reaction was carried out for 30 to 24 hours. After the saponification reaction, the fibers were washed several times with distilled water, and the washed fibers were dried at room temperature for 12 hours to prepare polyvinyl alcohol / polymethyl methacrylate blend fibers.

Comparative Example 1: Production of polyvinyl alcohol fiber

7 wt.% (W / w) of polyvinyl alcohol was added to distilled water as a solvent, and the mixture was stirred at 90 ° C. for 1 hour. Then, the prepared polyvinyl alcohol solution was stabilized at room temperature for about one hour. The stabilized solution was dipped in the coagulating solution and the spinning solution was discharged in the coagulating liquid and solidified to prepare the polyvinyl alcohol fiber.

Comparative Example 2: Preparation of polymethyl methacrylate fiber

7 wt.% (W / w) of polymethylmethacrylate was added to chloroform as a solvent, and the mixture was stirred at 40 ° C for 1 hour. Then, the prepared polymethylmethacrylate solution was stabilized at room temperature for about one hour. The stabilized solution was immersed in the coagulating solution and the spinning solution was discharged in the coagulating solution and solidified to prepare a polymethyl methacrylate fiber.

The mechanical strength measurements of the polyvinyl alcohol, polymethyl methacrylate fiber, and polyvinyl alcohol / polymethyl methacrylate blend fibers prepared in Examples 1 to 5, respectively, prepared in Comparative Examples 1 and 2 were carried out using a thermo-mechanical analyzer Respectively.

Name of sample Tensile Strength (MPa) PVA (Comparative Example 1) 15 PVA / PMMA (9/1) (Example 1) 13 PVA / PMMA (7/3) (Example 2) 30 PVA / PMMA (5/5) (Example 3) 48 PVA / PMMA (3/7) (Example 4) 67 PVA / PMMA (1/9) (Example 5) 80 PMMA (Comparative Example 2) 115

In Table 1, it can be seen that the polyvinyl alcohol / polymethyl methacrylate (9/1) blend fibers produced by the heterogeneous system saponification method according to the present invention are composed of the polyvinyl alcohol fibers prepared by the wet spinning method of Comparative Example 1 But the tensile strength increased with increasing ratio of polymethylmethacrylate (from 7/3) to polyvinyl alcohol fiber prepared by wet spinning.

Thus, according to the present invention, polyvinyl alcohol / polymethylmethacrylate blend fibers having a strength higher than that of pure polyvinyl alcohol fibers can be produced while increasing hydrophilicity rather than pure polymethylmethacrylate.

Claims (14)

Spinning a dope solution in which a vinyl ester polymer and an acrylic polymer are dissolved in a dope solvent to obtain precursor fibers; And
And subjecting the obtained precursor fibers to nonuniform saponification to convert the vinyl ester polymer to polyvinyl alcohol. ≪ Desc / Clms Page number 20 >
The method of producing a polyvinyl alcohol / acrylic polymer blend fiber according to claim 1, wherein the vinyl ester polymer is polyvinyl acetate.
The polyvinyl alcohol / acrylic resin composition according to claim 1, wherein the dope solvent is at least one selected from the group consisting of benzene, toluene, ethanol, xylene, butanol, methyl ethyl ketone, ethyl acetate, chloroform and dimethylformamide. ≪ / RTI >
The process for producing a polyvinyl alcohol / acrylic polymer blend fiber according to claim 1, wherein the total content of the vinyl ester polymer and the acrylic polymer dissolved in the dope solution is 1 to 30 wt%.
The poly (arylene ether) polymer film according to claim 1, wherein the content ratio of the vinyl ester polymer and the acrylic polymer dissolved in the dope solution is from 1:99 to 99: 1 (w / w) Vinyl alcohol / acrylic polymer blend fibers.
The method of claim 1, wherein the spinning of the dope solution is performed using wet spinning or ultra-high speed centrifugal spinning.
7. The process for producing a polyvinyl alcohol / acrylic polymer blend fiber according to claim 6, wherein the wet coagulation is performed so that the coagulating liquid is water, glycerin, butyl alcohol, xylene, glycol or a mixture thereof.
The non-uniform saponification according to claim 1, wherein the heterogeneous saponification is performed by impregnating a mixed solution of an acid or an alkali solution containing a dispersant and a swelling agent with a polyvinyl acetate / acrylic polymer blend fiber. The polyvinyl alcohol / acrylic polymer Gt;
The process for producing a polyvinyl alcohol / acrylic polymer blend fiber according to claim 8, wherein the dispersant is at least one selected from the group consisting of sodium sulfate, sodium sulfite, calcium sulfate and magnesium sulfate.
The method of claim 8, wherein the swelling agent is at least one selected from the group consisting of methanol, ethanol, propanol, ethylene glycol, propylene glycol, tetrahydrofuran (THF), dimethylsulfoxide (DMSO) Wherein the polyvinyl alcohol / acrylic polymer blend fiber is produced by a method comprising the steps of:
The process according to claim 8, wherein the heterogeneous saponification is carried out for a period of from 2 hours to 100 hours at a temperature range of from 5 ° C to 70 ° C.
A polyvinyl alcohol / acrylic polymer blend fiber produced by the method of any one of claims 1 to 11.
A fiber product comprising the polyvinyl alcohol / acrylic polymer blend fibers of claim 12, wherein the fiber product is a filament yarn, a staple fiber, a yarn, a nonwoven fabric, or a woven fabrics. .
A fiber-reinforced cement composite material comprising the polyvinyl alcohol / acrylic polymer blend fiber of claim 12.

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