KR101766894B1 - Processes for manufacturing Nonflammable Cellulose Fiber Structures and Nonflammable Cellulose Fiber Structures by the processes - Google Patents

Abstract

The present invention relates to a method for manufacturing a non-flammable cellulose fiber structure and a fiber structure manufactured thereby. The method of the present invention comprises: (a) a process in which a fiber structure containing a cellulose fiber is impregnated with aqueous solution containing phosphorus compounds and nitrogen compounds and then phosphorylation reaction is performed on the fiber structure under a nitrogen atmosphere at 200-400C; (b) a process in which the fiber structure on which phosphorylation reaction is performed is impregnated with sodium oxide solution to exchange ammonium ion with sodium ion; (c) a process in which the ion-exchanged fiber structure is impregnated with alcohol solution of silicon fluorides to couple with silicon ion; (d) a process in which the coupled fiber structure is impregnated with solution containing silicon emulsion; and (e) a process in which the impregnated fiber structure is dried at 250-300C. The solution containing the silicon emulsion comprises 100 parts by weight of water, 3-5 part by weight of silicon emulsion, and 3-5 parts by weight of a polymer of ammonium phosphate and guanidine sulfamate. Therefore, a cellulose fiber structure with excellent flame retardancy, heat resistance, and strength can be provided.

Description

TECHNICAL FIELD [0001] The present invention relates to a method for manufacturing a flame retardant cellulose-based fiber structure and a fiber structure by the method,

The present invention relates to a method for producing a flame retarded cellulose fiber structure and a fiber structure by the method, and more particularly to a method for producing a cellulose fiber structure excellent in flame retardancy, heat resistance and strength, .

Generally, the flame retardant material is a material that delays or cuts off the flame propagation when a fire occurs, and is used as a flame retardant material for insulation and flame retardant materials, building materials, and flame retardant barrier in high temperature facilities. Conventionally, inorganic materials such as asbestos, glass fiber, and gypsum have been widely used as flame retardant materials. However, due to environmental problems, these inorganic materials are only partially used or their usage is being reduced.

In addition to these, flame retardant materials produced by physical methods such as blending or compounding a polymer resin with a flame retardant agent or coating an aqueous solution of a flame retardant agent on a fiber structure are currently in use.

However, the flame retardant materials using these physical methods are advantageous in that they are easy to manufacture and have a low manufacturing cost, but have a very low flame retarding effect and have a disadvantage of deteriorating the inherent physical properties of the material.

Korean Patent Registration No. 10-0028991 discloses a flame-retardant processing method in which a woven or knitted fabric containing cellulose-based fibers is treated with a borohydride compound and then treated with an amidophospazene compound. However, the surface of such a flame retardant cellulosic material does not form a flame retardant film due to a chemical reaction, but because it is physically coated with a flame retardant film, the flame retardant film is easily washed with water. Due to the limited oxygen index (LOI), there are limits to maintaining essentially flame retardancy and heat resistance.

As a flame retardant material for solving such a problem, Korean Patent Registration No. 10-0310273 discloses a flame retardant comprising a cellulose phosphate ester compound produced by chemical reaction of a compound composed of phosphoric acid and urea at a high temperature of 200 to 300 ° C Material disclosure. However, this flame retardant material has excellent flame retardancy (limited oxygen index 30 to 40), but has a disadvantage in that the strength of the material is lowered.

Korean Patent Registration No. 10-0603023 discloses a process for producing a cellulose compound by reacting a cellulose fiber with a dicarboxylic acid anhydride to form a carboxylcellulose compound and ion-bonding the resulting carboxylcellulose compound with a refractory metal to form a metal carboxylcellulose compound And a process for forming a metal carboxylcellulose borate compound by adsorbing and reacting the metal carboxyl cellulose compound with boric acid to produce a flame retardant material. However, this flame retardant material also has excellent flame retardant properties (limited oxygen index 30 to 40 or more), but the strength of the material can not be reinforced.

KR 10-0028991 B1 KR 10-0310273 B1 KR 10-0603023 B1

Accordingly, the present invention provides a method for producing a flame retardant cellulose fiber structure having excellent flame retardance, heat resistance and strength, and a fiber structure by the method, in order to overcome the problems of conventional cellulose fiber structure.

In order to accomplish the above object, the present invention provides a method for producing a cellulose fiber structure, comprising: (a) impregnating a fibrous structure containing cellulose fibers into an aqueous solution containing a phosphorus compound and a nitrogen compound, (B) impregnating the phosphorylated fiber structure with an aqueous solution of sodium hydroxide to exchange ammonium ions and sodium ions; and (c) subjecting the ion-exchanged fibrous structure to a treatment of silicon chloride (D) impregnating the coupled fiber structure with a solution containing a silicone emulsion; (e) impregnating the impregnated fiber structure at a temperature of from 250 to 300 DEG C Wherein the solution containing the silicone emulsion comprises 100 parts by weight of water, 3 to 5 parts by weight of silicone emulsion, monium phosphate) and 3 to 5 parts by weight of a polymer of guanidine sulfamate (Guanidine Sulfamate).

The silicone emulsion is characterized by containing 1 to 10% by weight of a nonionic surfactant, 1 to 10% by weight of an amphoteric surfactant, 5 to 20% by weight of a silicone oil, and a residual amount of water.

Wherein the polymer is prepared by mixing ammonium phosphate and boric acid, introducing guanidine sulfamate in the presence of the mixture of ammonium phosphate and boric acid heated to 80 to 90 캜, introducing the guanidine sulfamate- Heating the solution to 130 ° C and maintaining the solution for 30 to 90 minutes to polymerize the ammonium phosphate and the guanidine sulfamate; and raising the temperature of the polymerized polymer to 140 to 160 ° C to crystallize the polymerized product .

The solution containing the silicone emulsion further comprises 1 to 3 parts by weight of magnesium hydroxide having a particle diameter of 100 to 800 nm.

The flame retardant cellulose-based fiber structure according to the present invention is characterized by being produced by the above-mentioned method.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a cellulose fiber structure excellent in flame retardance, heat resistance and strength as well.

Hereinafter, the present invention will be described in detail.

The method for producing a flame retardant cellulose fiber structure of the present invention comprises the steps of (a) impregnating a fiber structure containing cellulose fibers into an aqueous solution containing a phosphorus compound and a nitrogen compound, and then performing a phosphorylation reaction at 200 to 400 캜 under a nitrogen atmosphere (B) ion-exchanging the phosphorylated fiber structure with an ammonium ion and sodium ion under an aqueous solution of sodium hydroxide; (c) impregnating the ion-exchanged fibrous structure with an alcohol solution of silicon chloride to form a silicone (D) impregnating the coupled fiber structure with a solution comprising a silicone emulsion, and (e) drying the impregnated fiber structure at 250 to 300 ° C. .

Hereinafter, these steps will be described in detail.

(a) Cellulose system  A fibrous structure containing fibers is dispersed in an aqueous solution containing a phosphorus compound and a nitrogen compound Impregnated  Followed by phosphorylation at 200 to 400 ° C under a nitrogen atmosphere.

First, the cellulosic fiber structure is impregnated with an aqueous solution of 0.5-3 mol of a phosphorus compound and 1-3 mol of a nitrogen compound for 10 minutes to 5 hours, followed by drying. The reaction is carried out at a reaction temperature of 200-400 ° C for 10 minutes To < / RTI > 4 hours to form a cellulosic fiber structure comprised of an ammonium cellulose phosphate ester compound.

At this time, the obtained fiber structure has a phosphorus content of 5 to 15% by weight and a nitrogen content of 4 to 12% by weight.

In the present invention, the cellulose fiber structure may be one kind of material selected from the group consisting of viscose rayon, cotton and pulp, and may be in the form of a fiber, a woven fabric, a nonwoven fabric, a felt or a sheet.

The phosphorus compound may be phosphoric acid, ammonium deut phosphate and diammonium hydrogen phosphate, and the nitrogen compound may be urea, mono-, di- and triethanolamine, melamine and pyridine, but is not limited thereto.

(b) treating the phosphorylated fiber structure with an aqueous solution of sodium oxide Impregnated  Allowing the ammonium and sodium ions to exchange.

Then, the cellulose fiber structure composed of the phosphorylated fiber structure, that is, the ammonium cellulose phosphate ester compound is impregnated in an aqueous solution of 0.5 to 3 mols of sodium hydroxide for 30 minutes to 4 hours. When the sodium hydroxide aqueous solution is impregnated with a cellulose fiber structure composed of ammonium cellulose phosphate ester compound, an ion exchange reaction of ammonium ion and sodium ion is carried out to form a fiber structure composed of a cellulose sodium phosphate ester compound.

(c) Ion-exchanged  Fiber structure of silicon chloride Alcohol  To the solution Impregnated  With silicon ions Coupling  step.

Next, a fibrous structure composed of the sodium cellulose phosphate ester compound is impregnated with an alcohol solution containing 1 to 5% by weight of silicon chloride for 30 minutes to 3 hours for coupling reaction with silicon ions to form a silicone cellulose phosphate ester compound To produce a constructed fiber structure. At this time, the content of silicon coupled to the resultant fiber structure is about 1 to 10% by weight.

(d) Coupled  The fiber structure is made of silicon Emulsion  To the containing solution Impregnation The key is step.

Next, the coupled fiber structure is impregnated with a solution containing the silicone emulsion, and then, the residual solution remaining in the coupled fiber structure is removed. At this time, the impregnation time may be about 10 seconds to 1 minute, and a squeeze roller made of rubber or the like may be used to remove the remaining solution.

The solution containing the silicone emulsion may include 100 parts by weight of water, 3 to 5 parts by weight of silicone emulsion, and 3 to 5 parts by weight of a polymer of ammonium phosphate and guanidine sulfamate. And, if necessary, 1 to 3 parts by weight of the pigment.

Here, the water is preferably deionized water, but it is not limited thereto.

And the silicone emulsion comprises 1 to 10% by weight of a nonionic surfactant, 1 to 10% by weight of an amphoteric surfactant, 5 to 20% by weight of a silicone oil and a balance of water, Ethylene lauryl ether may be used. Examples of the amphoteric surfactants include methyl laurylaminopropionate, sodium laurylaminopropionate, lauryldimethyl, cocamidopropyl betaine, stearyldimethyl betaine, lauryl dihydro Hydroxyethyl betaine, and the like. The silicone oil preferably has a viscosity ranging from 10,000 to 500,000 cps, considering strength, impregnation property, and the like. The water is preferably deionized water.

The polymer of ammonium phosphate and guanidine sulfamate is intended to further improve the strength and flame retardancy of the fiber structure, comprising the steps of mixing ammonium phosphate and boric acid, and heating the mixture of ammonium phosphate and boric acid to 80-90 ° C Introducing guanidine sulfamate into the mixture, heating the mixture to which the guanidine sulfamate has been added at 110 to 130 ° C. and maintaining the mixture for 30 to 90 minutes to polymerize the ammonium phosphate and the guanidine sulfamate, And raising the temperature of the polymerized polymer to 140 to 160 ° C to crystallize the polymerized product.

That is, ammonium phosphate and boric acid are first mixed in a weight ratio of 1: 0.05 to 0.15 in the reactor. Then, it is heated to 80 to 90 ° C. Then, in a heated state, guanidine sulfamate is added thereto in a weight ratio of 1: 1 to 1.2: 1 with a mixture of ammonium phosphate and boric acid. Next, this is slowly heated to 110 to 130 ° C and maintained for 30 to 90 minutes to polymerize ammonium phosphate and guanidine sulfamate. Then, it is heated to a temperature of 140 to 160 ° C. Through the elevation of the temperature, the polymerizate in the reactor is uniformly liquefied, and the pressure in the reactor is raised. When the reaction is completed, the viscosity of the polymer in the reactor is increased. Specifically, the crystallization is exothermic in a viscosity range of 15,000 to 20,000 cps (brook field). The polymer thus crystallized has a molecular weight of 5,000 or more.

The reason for including step (d) in the present invention is that the fiber structure having been subjected to the step (c) has excellent thermal and flame retardant properties, but it is difficult to use due to poor strength, Because of the disadvantages, this step reinforces strength, eliminates the disadvantages of discoloration, and also improves the thermal and flame retardant properties.

(e) Impregnated  The fiber structure is heated at 250 to 300 ° C Dry  step.

Finally, the impregnated fiber structure is dried at 250 to 300 ° C for 1 to 30 minutes to remove water as a solvent.

Meanwhile, the solution containing the silicone emulsion may further contain 1 to 3 parts by weight of magnesium hydroxide having a particle diameter of 100 to 800 nm. In this case, the solution has further excellent strength and flame retardancy.

The smaller the particle diameter of the magnesium hydroxide is, the more excellent the flame retardancy characteristic can be exhibited. When the coarse particles having a particle diameter of 100 nm or less are poor in dispersibility and relatively coarse particles exceeding 800 nm are used, the surface of the fiber structure is roughened or affects the color surface.

The magnesium hydroxide is not particularly limited as long as it has a particle diameter in the range of 100 to 800 nm, and commercially available magnesium hydroxide can be used. Alternatively, magnesium hydroxide may be synthesized by using a known method to use particles obtained therefrom. However, the present invention is not limited thereto.

The fiber structure of the present invention produced by the above-described method has excellent flame retardancy and thermal properties, and is excellent in strength, and can be used in various fields such as fireproof clothing, fireproof materials for building materials and interior materials, heat insulating materials for high- There is an advantage that it can be used.

Hereinafter, the present invention will be described in more detail by way of examples.

(Example 1)

100 g of viscose rayon felt was impregnated in 1000 ml of 1 mol of phosphoric acid and 1 mol of urea for 1 hour and then dried at 90 캜 for 5 minutes to remove water. Thereafter, the resultant was heat-treated at 300 DEG C for 30 minutes in a muffle furnace under a nitrogen atmosphere to prepare a fiber structure made of an ammonium cellulose phosphate ester compound.

Next, the fibrous structure composed of the ammonium cellulose phosphate ester compound was impregnated into 1000 ml of an aqueous sodium hydroxide solution to perform an ion exchange reaction between ammonium ion and sodium ion, and the fibrous structure was dried at 50 DEG C for 10 minutes to obtain cellulose A fiber structure composed of a sodium phosphate ester compound was obtained. This was impregnated into 1000 ml of an alcohol solution containing 3% by weight of silicon chloride and dried at 100 DEG C for 5 minutes to obtain a fibrous structure composed of a silicone cellulose phosphate ester compound.

Next, the fibrous structure composed of the silicone cellulose phosphate ester compound was impregnated in a solution containing the silicone emulsion for 60 seconds, and the resultant was taken out, passed between rubber squeeze rollers to remove the remaining solution, dried at 280 DEG C for 5 minutes Respectively.

Here, the solution containing the silicone emulsion was prepared by thoroughly mixing 800 g of deionized water, 40 g of silicone emulsion, and 32 g of polymer at 100 rpm at room temperature for 10 minutes.

Then, 10 g of a nonionic surfactant (polyoxyethylene lauryl ether) and 10 g of a cationic surfactant (cocamidopropyl betaine) were added to 80 g of deionized water, and the temperature was elevated to maintain the silicone emulsion at 80 ° C. for 30 minutes . Then, 20 g of polydimethylsiloxane (viscosity: 500,000 cps) oil was added and stirred at about 100 rpm for 1 hour. Then, 80 g of deionized water was added while the temperature was lowered to about 50 캜, and the mixture was stirred at about 80 rpm for 1 hour. Then, the mixture was stirred at 50 DEG C and 80 rpm for 30 minutes, and the resulting mixture was homogeneously mixed.

The polymer was charged with 100 g of ammonium monophosphate and 10 g of boric acid into a 1-liter reaction vessel equipped with a stirrer, a thermometer and a condenser, and heated to 80 ° C. After stirring for about 30 minutes, 100 g of guanidine sulfamate was added. After the introduction of guanidine sulfamate, the mixture was heated to 120 ° C in a sealed state and reacted for about 1 hour. The reaction mixture was gradually heated to 150 ° C. and further reacted for 4 hours. Then, the viscosity was measured and the crystal was discharged at 16,000 cps.

(Example 2)

In the preparation of the solution containing the silicone emulsion, 6 g of magnesium hydroxide having a particle size of 500 nm was further mixed.

(Comparative Example 1)

The procedure of Example 1 was repeated except that the fiber structure was impregnated with the solution containing the silicone emulsion and the squeeze roller was passed through and dried.

(Test Example 1)

The thermal properties, flame retardancy and strength of the flame retarded cellulose fiber structure produced according to the present invention were measured.

The thermal properties were measured by thermogravimetric analyzer (DuPont 951) by measuring the loss of fiber samples at the time of heating. Briefly, 5 mg of the fiber sample was heated to 700 ° C at a temperature elevation rate of 10 ° C / min under a nitrogen atmosphere to measure the loss of the fiber sample, and the weight loss of the sample was expressed as a percentage.

The flame retardancy was evaluated by measuring the LOI value (Limited Oxygen Index). In general, the flame retardant properties are expressed in terms of the limiting oxygen index (LOI) according to ASTM D2863, which is required when the combustion time of three or more specimens lasts for 3 minutes or until combustion is continued until the carbonized length is 5 cm The lowest oxygen flow rate and the nitrogen flow rate are measured and calculated by the following formula.

Limiting oxygen index _{(LOI) = [O 2]} / [O 2 + N 2]

Here, [O ₂ ] represents the oxygen flow rate (l / min) and [N ₂ ] represents the nitrogen flow rate (l / min).

The strength evaluation was carried out by measuring the abrasion strength, and according to ISO 12947-2, the test piece breaking point was measured by the Martindale Method. The specimens were prepared in the form of a circle with a diameter of 38 mm. Five specimens were prepared for each specimen. The total effective wear load (ie, the weight of the specimen holder and the weight of the test specimen) was 595 ± 7 g (nominal load of 9 kPa) And the average value is measured. The abrasion test continues until the failure of the specimen. The breaking point of the specimen is defined as the diameter of the first hole caused by abrasion on the specimen of 0.5 mm or more. The test environment was 20 ± 2 ° C and 65 ± 2%.

In this test, viscose rayon felt without chemical treatment was used as the control group 1, and product (Kanecaron Sys, trade name, Kanecaron Co., Kanecaron Co., Kanecaron Sys) used as a conventional flame retardant as the control group 2 was used.

The results are shown in Table 1 below.

Test Example 1 Results division Example 1 Example 2 Comparative Example 1 Control 1 Control group 2 LOI 48 50 40 17 32 Weight loss by temperature (%) 300 ° C 3 3 8 30 15 400 ° C 7 7 12 78 29 500 ℃ 10 9 15 85 36 Wear strength (times) 21,000 22,100 3,500 4,000 17,000

As shown in Table 1, the fibrous structure according to the present invention has a very high limiting oxygen index, has a low weight loss according to temperature, has excellent flame retardancy and thermal properties, and has a significantly higher strength than Comparative Example 1, And it was confirmed that it is excellent.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It will be understood that the invention may be practiced. It is therefore to be understood that one embodiment described above is illustrative in all aspects and not restrictive.

Claims (5)

(a) impregnating a fibrous structure containing cellulose-based fibers in an aqueous solution containing a phosphorus compound and a nitrogen compound, followed by phosphorylation at 200 to 400 ° C under a nitrogen atmosphere;
(b) impregnating the phosphorylated fiber structure with an aqueous solution of sodium oxide to exchange ammonium and sodium ions, and
(c) impregnating the ion-exchanged fibrous structure with an alcohol solution of silicon chloride to couple with silicon ions,
(d) impregnating the coupled fiber structure with a solution comprising a silicone emulsion,
(e) drying the impregnated fibrous structure at 250 to 300 DEG C,
The solution containing the silicone emulsion comprises 100 parts by weight of water, 3 to 5 parts by weight of a silicone emulsion and 3 to 5 parts by weight of a polymer of ammonium phosphate and guanidine sulfamate ((Guanidine Sulfamate)
The polymer,
Mixing ammonium phosphate and boric acid,
Introducing guanidine sulfamate into the mixture of ammonium phosphate and boric acid at 80 to 90 ° C,
Heating the mixture to which the guanidine sulfamate has been added at 110 to 130 ° C. for 30 to 90 minutes to polymerize the ammonium phosphate and the guanidine sulfamate,
And a step of raising the temperature of the polymerized polymer to 140 to 160 ° C to crystallize the polymerized product.
The method according to claim 1,
Wherein the silicone emulsion comprises 1 to 10% by weight of a nonionic surfactant, 1 to 10% by weight of an amphoteric surfactant, 5 to 20% by weight of a silicone oil, and a residual amount of water. Way.
delete The method according to claim 1,
Wherein the solution containing the silicone emulsion further comprises 1 to 3 parts by weight of magnesium hydroxide having a particle diameter of 100 to 800 nm.
A flame retarded cellulose fiber structure, characterized in that it is produced by the process of any one of claims 1, 2 and 4.