KR100737977B1 - Flame retardant polyester fabric and manufacturing method thereof - Google Patents

Abstract

A non-flammable polyester fiber and a method for manufacturing the same are provided to realize a polyester fiber having an excellent flame resistant property, by adding titanium dioxide to polyalkylene terephthalate containing phosphorous-based non-flammable agent. Titanium dioxide of 0.5-2.5 wt% is added to polyalkylene terephthalate, in which a phosphorous-based nonflammable agent containing phosphorous element of 3,500-10,000 ppm is added during a polycondensation reaction. The polyalkylene terephthalate in which the titanium dioxide is added is dried. A POY(Partially Oriented Yarn) is manufactured by melting the dried polyalkylene terephthalate through an extruder and spinning the polyalkylene terephthalate through a spinneret at a winding speed of 3,000-3,500 m/min. The POY is twisted through a twisting unit to produce a twist yarn.

Description

Flame retardant polyester fiber and its manufacturing method {FLAME RETARDANT POLYESTER FABRIC AND MANUFACTURING METHOD THEREOF}

The present invention relates to a flame retardant polyester fiber and a method for manufacturing the same, and more particularly, to a polyalkylene terephthalate added with phosphorus-based flame retardant during polycondensation reaction, by adding 0.5 to 2.5% by weight of titanium dioxide, and having excellent flame retardancy and harmful gas. And a full-dull flame-retardant polyester fiber in which deterioration of mechanical properties hardly occurs and a method of manufacturing the same.

In general, polyester has excellent mechanical properties and chemical properties such as chemical resistance, so that it is widely used not only as a fiber but also as a film, an engineering plastic, etc., but has a disadvantage in that it is easy to burn. Recently, the developed countries have emphasized the flame retardant function of the fire to prevent fires, and the law strongly stipulates the use of flame retardant fibers in textile products, children's pajamas, aircraft, and car seat covers used in public facilities. Relevant regulations on flame retardancy have been reinforced in the same public facilities, requiring the use of flame retardant fibers, and the demand for flame retardant polyester fibers due to the expansion of the market of flame retardant fibers is expected to increase significantly compared to general polyester. have.

On the other hand, there are three main methods for imparting flame retardance to polyester fibers. First, a method of chemically bonding (copolymerizing) the flame retardant material at the time of polymerization, second, a method of adding the flame retardant material at the time of spinning, and third, a method of treating the fiber surface with the flame retardant material. Among these three methods, a method of adding a flame retardant material during spinning has a problem of lowering radioactivity and adversely affecting yarn properties, and a method of treating a fiber surface with a flame retardant material can reduce costs, but it is flame retardant by washing. Since the material is released, there is a problem in durability. On the other hand, the method of copolymerizing a flame retardant material during polymerization is most widely used because it is almost similar to the general polymerization process of polyester and has excellent durability. In this case, examples of the flame retardant used include bromine (Br) flame retardants and phosphorus (P) flame retardants.

Looking at the mechanism of action of the flame retardants, bromine-based flame retardants form bromine radicals, which act as a chain transfer agent to reduce the activity of radicals generated by pyrolysis at each stage, thereby inhibiting pyrolysis, suppressing flammable gas generation, and expanding combustion. Acts as a prevention. Phosphorus-based flame retardants react with oxygen to form phosphorus pentoxide and ortho phosphoric acid to act as dehydration carbonization catalysts to control the generation of flammable gases during pyrolysis. And it becomes a polyphosphoric acid and serves to block the contact with oxygen by coating the polymer fiber.

Examples of using a brominated flame retardant include Japanese Laid-Open Patent Publication Nos. 62-6912, 53-46398, 51-28894, and the like. Since a large amount is used, there is a problem that the polymer is discolored, and thus the light resistance is poor, and toxic gas is generated during combustion to contaminate the environment.

Examples of using phosphorus-based flame retardants include U.S. Patent Nos. 3,941,752, 5,399,428 and 5,180,793, and Japanese Patent Application Laid-Open No. 50-56488. Since the phosphorus atoms of the flame retardant are bonded to the main chain of the polymer, Physical properties are degraded by hydrolysis during post-processing of the ester fibers. In addition, it is decomposed without being volatilized by heat to release non-combustible gas such as water, carbon dioxide, sulfur dioxide, hydrogen chloride, and endothermic reaction. In the gas phase, the flammable gas is diluted to coat the polymer resin surface to prevent oxygen access, and at the same time, the polymer material is cooled through an endothermic reaction in the solid phase to reduce the generation of pyrolysis products. It is necessary to contain a large amount of flame retardant to ensure proper flame retardancy, the addition of such a large amount of phosphorus-based flame retardant is causing the problem of limiting the use of the physical properties of the thermoplastic polymer fiber itself.

On the other hand, Japanese Laid-Open Patent Publication No. 2003-247167 discloses a technique of imparting flame retardancy by using a non-halogen flame retardant to the fabric of pulled polyester fibers. On the other hand, since the flame retardant polyester fiber is required to have a low gloss and low light transmittance, the present invention is to impart flame retardancy by the method of the back salt treatment on the pulled polyester fiber. However, the invention has a process loss due to the posterior salt treatment and the process cost is increased. In particular, the use of the product was subject to restrictions on securing permanent flame retardancy, such as by washing.

In order to solve the above problems, an object of the present invention is to add 0.5 to 2.5% by weight of titanium dioxide to a polyalkylene terephthalate added with a phosphorus-based flame retardant in a polycondensation reaction to have a full dull property and excellent flame retardancy while And it provides a flame-retardant polyester fiber and a method of manufacturing the same that hardly causes a decrease in mechanical properties.

In order to achieve the above technical problem, the flame-retardant polyester fiber according to one feature of the present invention, 0.5 to 2.5% by weight of titanium dioxide is added to the polyalkylene terephthalate to which the phosphorus-based flame retardant is added during the polycondensation reaction.

The phosphorus flame retardant is preferably represented by the following formula (1), the content of phosphorus element 3,500 ~ 10,000ppm is added.

However, R _1, R ₂ is a mono-hydroxyalkyl group or a hydrogen atom of the C _{1 ~ 18} alkyl group, C _{1 ~ 18} aryl group, C _{1 ~ 18} of, R ₃ is an alkyl group of C _{1 ~ 18,} or C _{1 ~ It} is an aryl group of ₁₈ , and n is an integer of 1-4.

The polyalkylene terephthalate may be preferably any one or more compounds selected from the group consisting of polyethylene terephthalate, polypropylene terephthalate and polybutylene terephthalate.

On the other hand, the intrinsic viscosity of the flame retardant polyester fiber produced through the above configuration is preferably 0.65 ~ 0.75.

Method for producing a flame retardant polyester fiber according to another feature of the present invention, in the production of flame retardant polyester fibers, (1) during the polycondensation reaction to the polyalkylene terephthalate to which the phosphorus-based flame retardant represented by the formula (1) is added Adding 0.5 to 2.5% by weight of titanium, drying the titanium dioxide-added polyalkylene terephthalate, (3) melting the dried polyalkylene terephthalate with an extruder and spinning through a spinneret Preparing a partial alignment yarn; And (4) producing the false twist yarn by twisting the partial alignment yarn through a twist fitting.

Step (2) may be preferably made of a pre-drying step and the present drying step.

Step (3) is preferably spun at a winding speed of 3,000 to 3,500 m / min.

The polyalkylene terephthalate is preferably any one or more compounds selected from the group consisting of polyethylene terephthalate, polypropylene terephthalate and polybutylene terephthalate.

It is also possible to further include the step of stretching the partial orientation yarn between the third step (3) and the fourth step (4).

Hereinafter, the present invention will be described in more detail.

Flame retardant polyester fiber according to an embodiment of the present invention, in the polycondensation reaction is added 0.5 to 2.5% by weight of titanium dioxide to the polyalkylene terephthalate to which the phosphorus-based flame retardant is added.

The polyalkylene terephthalate used for this invention consists of at least 1 sort (s) of copolyester mainly having a polyalkylene terephthalate and a polyalkylene terephthalate. As the polyalkylene terephthalate, polyethylene terephthalate, polypropylene terephthalate and polybutylene terephthalate are preferable from the viewpoints of heat resistance, mechanical properties, availability, and cost.

As co-polyester which mainly made polyalkylene terephthalate, the copolyester which contains the said polyalkylene terephthalate mainly and contains a small amount of copolymerization components is mentioned.

In the above description, "mainly" means containing 80 mol% or more in the total polyester.

As said copolymerization component, for example, isophthalic acid, orthophthalic acid, naphthalenedicarboxylic acid, paraphenylenedicarboxylic acid, trimellitic acid, pyromellitic acid, succinic acid, glutaric acid, adipic acid, superlinic acid, azelaic acid, sebacic acid , Polyhydric carboxylic acids such as dodecane diacid, derivatives thereof, dicarboxylic acids containing sulfonic acid salts such as 5-sodium sulfoisophthalic acid and dihydroxyethyl 5-sodium sulfoisophthalic acid, derivatives thereof, and 1,2- Propanediol, 1,3-propanediol, 1,4-propanediol, 1,6-hexanediol, neopentylglycol, 1,4-cyclohexanedimethanol, diethylene glycol, polyethylene glycol, trimethylolpropane, pentaeryt Ritol, 4-hydroxy benzoic acid, (epsilon) -caprolactone, etc. are mentioned.

The copolyester is preferably a production method in which a small amount of copolymerized components are reacted with a terephthalic acid and a derivative thereof (e.g., methyl terephthalate) and a polymer of alkylene glycol in general, in terms of stability and simplicity of operation. .

Moreover, you may superpose | polymerize the thing which contains the monomer or oligomer component which is a copolymerization component further in the mixture of terephthalic acid and its derivative (for example, methyl terephthalate) and alkylene glycol which becomes a principal.

The copolymerized polyester should just be polycondensed in the main chain or side chain of the polyalkylene terephthalate which becomes a main body, and there is no special limitation in a copolymerization method.

On the other hand, as an example of the copolyester which mainly consists of polyalkylene terephthalate, the polyester which copolymerized the polyethylene terephthalate mainly and copolymerized the ethylene glycol ether of bisphenol A, and the 1, 4- cyclohexane dimethanol And polyester obtained by copolymerizing dihydroxyethyl 5-sodium sulfoisophthalate. Among these, polyester copolymerized with ethylene glycol ether of bisphenol A and polyester copolymerized with 1,4-cyclohexanedimethanol are preferable from the viewpoint of heat resistance and ease of production.

The said polyalkylene terephthalate and copolyester may be individual, or may mix 2 or more types.

Phosphorus-based flame retardant added to the flame-retardant polyester of the present invention, preferably phosphorus-based flame retardant represented by the formula (1) has the advantage that can be copolymerized with polyethylene terephthalate as a reactive flame retardant, has a higher flame retardant effect than the additive In addition, flame retardancy is maintained even after washing.

[Formula 1]

However, R _1, R ₂ is a mono-hydroxyalkyl group or a hydrogen atom of the C _{1 ~ 18} alkyl group, C _{1 ~ 18} aryl group, C _{1 ~ 18} of, R ₃ is an alkyl group of C _{1 ~ 18,} or C _{1 ~ It} is an aryl group of ₁₈ , and n is an integer of 1-4.

The phosphorus-based flame retardant is preferably added in the polycondensation process of the polyalkylene terephthalate, but is not limited by the addition time. The amount of phosphorus flame retardant to be added is preferably added 3,500 ~ 10,000ppm based on the number of people in the polymer to be polymerized. If the amount is less than 3,500ppm, the addition effect is insignificant, and if it exceeds 10,000ppm, the melt viscosity of the polymer is lowered, so that the spinability is poor and the physical properties are deteriorated.

In the present invention, 0.5 to 2.5% by weight of titanium dioxide is added to obtain full dull property without causing a decrease in the mechanical properties of the flame retardant polyester fiber produced.

The titanium dioxide is preferably added to the polycondensation reaction step after the esterification reaction, but is not limited by the addition time.

On the other hand, the amount of titanium dioxide added is 0.5 to 2.5% by weight based on the total flame retardant polyester fibers, more preferably 1.0 to 2.0% by weight is added. If it is less than 0.5% by weight, the matte effect cannot be obtained and the light transmittance is too high. If it exceeds 2.5% by weight, the workability is lowered.

On the other hand, not only has the effect of improving the stretchability, dyeing and sensitivity of the flame retardant polyester fiber produced by the addition of titanium dioxide, but also imparted flame retardancy by post-processing because it imparted flame retardancy in the polycondensation step of the polymer There is no need for this.

Meanwhile, the flame retardant polyester of the present invention may further include a polymerization catalyst and a color tone improving agent as other additives.

Antimony oxide, antimony acetate, tetrabutyl titanate, tetraisopropyl titanate, zinc acetate, tin compounds such as germanium dioxide, monobutyl or dibutyl, and manganese acetate are generally used as the polymerization catalyst. . The content of the catalyst is such that the metal content is 10 to 1,000 ppm with respect to the total polyester fiber.

If it is less than 10 ppm, the activity of the catalyst is too low, and if it exceeds 1,000 ppm, there is a possibility that this substance is formed and the cost increases.

In addition, a heat stabilizer for improving the physical properties of the flame-retardant polyester fiber produced and a color tone improver for improving the color tone can be added. As the heat stabilizer, phosphoric acid, trimethyl phosphate, triethyl phosphate, triphenyl phosphate (or phosphite instead of phosphate) and the like are added in an amount of less than 2,000 ppm based on the weight of the polyester, but 2,000 ppm is added. When used in excess, the activity of the catalyst may decrease. As a color tone improving agent, metal salts, such as cobalt acetate, are used, and the addition amount thereof generally depends on the quantity added to a fiber.

As for the intrinsic viscosity of the flame-retardant polyester fiber manufactured through the said structure, 0.65-0.75 are preferable. If the intrinsic viscosity is less than 0.65, if the intrinsic viscosity is less than 0.65, the workability of the fiber obtained is inferior and the mechanical strength of the obtained fiber tends to be lowered. If the intrinsic viscosity is higher than 0.75, the melt viscosity increases with increasing molecular weight, thereby making the pipeline unbearable. Melt spinning may be difficult due to problems such as failure or bursting, or fineness and cross section may be uneven.

In the method for producing a flame retardant polyester fiber of the present invention, in the production of flame retardant polyester fiber, (1) in the polycondensation reaction described above, titanium dioxide 0.5 is added to the polyalkylene terephthalate to which the phosphorus-based flame retardant represented by the formula (1) is added. Adding 2.5 wt%, (2) drying the titanium dioxide-added polyalkylene terephthalate, and (3) melting the dried polyalkylene terephthalate with an extruder and spinning through spinneret. Manufacturing a partial alignment yarn, and (4) burning the partial alignment yarn through a combustion facility to produce a false twist yarn.

In the step (1), 0.5 to 2.5% by weight of titanium dioxide is added to the polyalkylene terephthalate to which the phosphorus-based flame retardant is added during the polycondensation reaction. The copolymerized phosphorus flame retardant may be preferably used a phosphorus flame retardant represented by the formula (1). Moreover, the polyalkylene terephthalate of the structure mentioned above can be used for polyalkylene terephthalate.

In step (2), the polyalkylene terephthalate to which titanium dioxide is added is dried. The degree and method of drying may be as long as the fiber is dried at the previous stage of the normal spinning, but preferably, it can be dried in two stages of predrying and main drying.

In the step (3), the dried polyalkylene terephthalate is melted by an extruder and spun through a spinneret to produce a partial alignment yarn, thereby manufacturing various types of synthetic fibers using spinnerets having various discharge holes. can do. In this case, the spinning temperature is preferably maintained at 275 ~ 290 ℃, it is good to spin at a winding speed of 3,000 ~ 3,500 m / min.

In the step (4), the partial orientation yarn is twisted through a conventional combustion facility to produce a false twist yarn, and more preferably, the partial orientation yarn is stretched between the third and fourth steps. It is also possible to include further steps.

Through the following examples will be described the present invention in more detail. This example is intended to explain the present invention more specifically through the most preferred embodiments, and the scope of the present invention is not limited to these examples.

Example 1

1.0 weight% of titanium dioxide was added to the polyethylene terephthalate which is the intrinsic viscosity 0.67 copolymerized with the phosphorus flame retardant represented by General formula (1) whose phosphorus (P) element content in a polymer is 7000 ppm. Thereafter, predrying was performed at 120 ° C. for 3 hours, and main drying was performed at 150 ° C. for 6 hours to prepare chips. After melting the chip with a melt extruder, 36 discharge holes were spun through a punched spinneret to prepare partially drawn yarn at a winding speed of 3,000 m / min. Thereafter, the twisted yarn was manufactured using a conventional twisting equipment at a draw ratio of 1.7 and a twist rate of 450 m / min.

Example 2

A false-twisted yarn was prepared in the same manner as in Example 1 except that 2.0 wt% of titanium dioxide was added.

Comparative Example 1

A false-twisted yarn was prepared in the same manner as in Example 1 except that 0.4 wt% of titanium dioxide was added.

Comparative Example 2

A false-twisted yarn was prepared in the same manner as in Example 2 except that the phosphorus-based flame retardant was not copolymerized.

The physical properties of the false twisted yarns prepared in Examples 1 and 2 and Comparative Examples 1 and 2 were evaluated in the same manner as shown in Table 1 below.

One. Radiation workability

The number of yarns wound without thread trimming for one week was used as the denominator, and the number of yarns with thread trimming recorded was evaluated as a percentage.

2. Dullness

Dullness is a quality characteristic that is evaluated emotionally, such as human vision and touch, and it is good if 10 people have a perfect score of 3.5 out of 5 for each false score of Example 1 to Comparative Example 2. If it is less than that, it divided into defective and determined.

3. Limit Oxygen Index

In order to evaluate the flame retardancy, it was measured according to KS-M ISO 4589-1.

4. 45 ° Gradient

In order to evaluate the flame retardancy, it was measured according to KS-K0580.

TABLE 1

As can be seen in Table 1, when the critical value of the titanium dioxide is out of the range of the present invention, the DULL property becomes very poor, and it is difficult to obtain flame retardancy unless the phosphorus-based flame retardant of the present invention is added. You can check it.

Flame retardant polyester fibers of the present invention can be produced in a glossy and matt flame-retardant polyester fiber without the addition of the rear salt by adding titanium dioxide to the polyalkylene terephthalate to which the phosphorus-based flame retardant is added during the polycondensation reaction. As a result, it is possible to reduce various processes for giving polyester fibers looseness, which is very effective in manufacturing time and cost. In addition, the flame retardancy can be maintained by washing or the like in the process of using the product.

Although the present invention has been described in detail only with respect to the embodiments described, it will be apparent to those skilled in the art that various modifications and variations are possible within the technical spirit of the present invention, and such modifications and variations belong to the appended claims. .

Claims (8)

delete delete delete delete In the method for producing a flame retardant polyester fiber, (1) adding 0.5 to 2.5% by weight of titanium dioxide to the polyalkylene terephthalate to which the phosphorus content in the polycondensation reaction is 3,500 to 10,000 ppm and to which the phosphorus-based flame retardant represented by Formula 1 is added; (2) drying the polyalkylene terephthalate added with titanium dioxide; (3) melting the dried polyalkylene terephthalate with an extruder and spinning a spinneret at a winding speed of 3,000 m / min to 3,500 m / min to produce a partial alignment yarn; And (4) a method of producing a flame retardant polyester fiber, comprising the step of producing the false twisted yarn by twisting the partial oriented yarn through a flammable facility. [Formula 1]

However, R _1, R ₂ is a mono-hydroxyalkyl group or a hydrogen atom of the C _{1 ~ 18} alkyl group, C _{1 ~ 18} aryl group, C _{1 ~ 18} of, R ₃ is an alkyl group of C _{1 ~ 18,} or C _{1 ~ It} is an aryl group of ₁₈ , and n is an integer of 1-4. delete The method of claim 5, Wherein said polyalkylene terephthalate is at least one compound selected from the group consisting of polyethylene terephthalate, polypropylene terephthalate and polybutylene terephthalate. The method of claim 5, The method of producing the flame retardant polyester fiber, characterized in that it further comprises the step of stretching the partial oriented yarn between step (3) and (4).