KR20060078606A - A technical polyester fibers with high flame retardancy - Google Patents

Abstract

The present invention relates to an industrial polyester fiber having excellent flame retardancy and a method of manufacturing the same, and more particularly, to an industrial polyester fiber having a superior flame retardancy and suitable for coating reinforcement of industrial fibers such as tarpaulin and truck cover, and a method for producing the same. will be.

In the method for producing a flame retardant polyester fiber according to the present invention, the phosphorus-based flame retardant is solid phase polymerized copolymerized low viscosity chip containing 5,000-6,000 ppm of TiO ₂ and 500-3,000 ppm of TiO ₂ to increase the viscosity to 0.85 or more. Thereafter, the flame-retardant solid-state polymerization chip is melted and spun through a spinneret to produce a cooled solidified non-drawn yarn, and the stretching, heat treatment and relaxation processes are applied while the undrawn yarn passes through a pair of high-pressure rollers. At this time, the winding conditions are total draw ratio 5.3-5.8, relaxation ratio 11-15%, high roller temperature 230-240 ℃.

The flame-retardant polyester fiber produced by the method of the present invention exhibits a physical property of less than 6.5g / d strength, dry heat shrinkage (190 ℃, 15 minutes, ultra-load 0.01g / d, test light) 6.0% or less, flame-retardant performance is limited oxygen The LOI value is 32 or more on an exponential basis.

Polyester fiber, flame retardant, shrinkage

Description

A technical polyester fibers with high flame retardancy}             

1 is a schematic view showing a manufacturing process according to the present invention.

* Explanation of symbols on the main parts of the drawing *

A: Common spinning emulsion applying device (Kiss Roller or Jet Oiler)

The present invention relates to an industrial polyester fiber excellent in flame retardancy and a method of manufacturing the same.

Polyester fibers are excellent in many properties, and their use is being expanded as industrial fibers, and interest in high strength and low shrinkage characteristics is increasing.

Techniques disclosed in the related art for producing flame retardant polyester fibers using phosphorus-based flame retardants are mainly limited to medical professionals. Looking at the prior arts, most of the technologies that impart additional properties besides flame retardancy (dyeing resistance, light fastness, abrasion properties, thermal stability, UV stability, deodorization, anti-pilling property, high shrinkage resistance, hydrolysis resistance), For example, Korean Patent Application Nos. 10-2001-7008962, 10-1999-0013878, 10-1997-0042303, 10-1997-0041727 and Japanese Patent Application No. 3-234053, Japanese Patent Application No. 4-357067, Korean Patent No. 5-245286 and many other patents disclose such a technique.

In addition, as related technologies for spinning conditions, prior arts related to spinning speed, detention temperature, cooling conditions, draw ratio, chip intrinsic viscosity, shear rate in nozzle hole, and spinning draft are disclosed in Korean Patent Application Nos. 10-2001-0045361 and 10-1998. -0039370, Japanese Patent Application Laid-Open Nos. 11-232978, 11-270792, and 2001-326742.

Techniques for flame retardant polymerization are disclosed in Korean Patent Application Nos. 10-1996-0004287, 10-1995-0025122, 10-1991-0024079, and Japanese Patent Application No. 3-267058, and Japanese Patent Application No. 57-1669871. Techniques for improving flame retardancy by simultaneously containing a phosphorus flame retardant and halogen or other components are disclosed in Korean Patent Application Nos. 10-1997-0004811, 10-1997-0004810, 10-1996-0035096, and 10-1996-0025675. Is disclosed.

Looking at the prior art relating to the properties of flame retardant polyesters, Japanese Patent Application No. 63-282143 discloses a manufacturing technique for achieving flame retardant yarns with a strength of 5.5 g / d or more by a conventional melt spinning method, and US Pat. Flame retardant polyester chips are used to produce flame retardant yarns with properties ranging from strength of 7.48-9.39 g / d to dry heat shrinkage of 5.3-20% at 200 ° C, but the final production speed is 300m / min. It is disadvantageous in commercial terms.

In case of general polyester fiber used as reinforcement material for industrial tarpaulin or truck cover, it is proposed to give flame retardancy by changing the composition of PVC used as coating material to secure the flame retardancy of the final product. In order to impart the thickness of the PVC coating layer has a problem.

It is an object of the present invention to provide a flame retardant polyester and a method for producing the same, which can be economically produced while raising the flame retardant yarn production technology, which is currently mainly developed only for medical use, to a level suitable for industrial use.

Another object of the present invention is an industrial polyester yarn having excellent flame retardancy which can solve the problem of increasing the thickness of the coating layer, which is a problem that occurs when imparting flame retardancy by changing the PVC composition in order to impart flame retardance to the final product tarpaulin or truck cover, To provide a way.

According to the present invention, there is provided an industrial polyester fiber having excellent flame retardancy and a method for manufacturing the same, wherein the polyester fiber has a high strength and low shrinkage while passing through a pair of high rollers by melt-spun and cold-hardened flame-retardant polyester filament undrawn yarn After being stretched and relaxed to have properties at the same time, it is manufactured by winding the winder to have the characteristics of flame retardancy, high strength, and low shrinkage.

According to a preferred embodiment of the present invention, the polyester fiber according to the present invention contains 5000-6000 ppm of phosphorus-based flame retardant such as formula (1) below, and 500-2500 ppm of TiO ₂ during the polyester polymerization process. It is characterized by.

According to another suitable embodiment of the present invention, the method for producing a polyester fiber according to the present invention is a total draw ratio of 5.3 to 5.8, a relaxation ratio of 11 to 22 while passing through a plurality of roller boxes of the cooled non-drawn polyester yarn 15%, the loosening zone Godt Roller (Godet Roller) temperature is characterized in that the final winding after giving heat setting and relaxation under the conditions of 230 ~ 240 ℃.

Formula 1

R1 and R2 in Formula 1 above are the same or different radicals having a hydrogen atom or a ω-hydroxy group having 2 to 4 carbon atoms, p is an integer of 1 to 5.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail.

The present invention is a direct spinning process, wherein the polyester melt exiting through the spinneret is in a cooled, unstretched state prior to GR1. The undrawn yarn is drawn between GR1 and GR4, undergoes a first heat setting process in GR4, and then undergoes a first relaxation between GR4 and GR5, and a second heat setting in GR5, and finally, between GR5 and GR6. The final winding is followed by a second relaxation process.

According to the present invention, the shrinkage rate can be used as an industrial fiber by optimizing the amount of TiO _{2 that} can act as a nucleating agent due to the decrease in the crystallinity caused by the steric hindrance effect caused by copolymerization of the phosphorus-based flame retardant in the polymer chain. Can be reached.

The phosphorus flame retardant is preferably 5,000 to 6,000 ppm phosphorus content compared to the fiber, when less than 5,000 does not express the appropriate level of flame retardant performance, if it exceeds 6000 ppm, the flame retardant component in the polyester main chain is excessive, the physical properties of the appropriate level Is difficult to achieve. In addition, the content of TiO ₂ acting as a nucleating agent is preferably 500-3,000 ppm relative to the fiber, and if less than 500, the crystal growth in the yarn is not sufficient, and when the content exceeds 3,000 ppm, the elongation is increased by increasing the degree of crystallinity. There is a problem that the workability is reduced.

The intrinsic viscosity of the solid-state polymerized flame-retardant polyester chip used for the implementation of the present invention is preferably about 0.85 ~ 1.0, and if the intrinsic viscosity is less than 0.85, spinning workability is unstable and the intrinsic viscosity is 1.0 to produce a high strength yarn If exceeded, the effect of viscosity increase cannot be expected due to decomposition of the polymer due to the increase in shrinkage rate and the increase in spinning temperature.

The polyester fiber according to the present invention is manufactured under conditions of a total draw ratio of 5.3 to 5.8, a relaxation ratio of 11 to 15%, and a loosening area high roller temperature of 230 to 240 ° C. to have properties of flame retardancy, high strength, and low shrinkage. . In the manufacturing process, if the draw ratio is less than 5.3, it is difficult to express strength due to low fiber orientation, whereas, if the draw ratio exceeds 5.8, the overstretched level is reduced, and workability is decreased or complete trimming occurs. In addition, when the relaxation rate is less than 11%, the shrinkage rate is increased, and when the relaxation rate is more than 15%, there is a problem that it is difficult to secure workability due to a severe vibration on the high roller. The temperature of the loosening roller is 230-240 ℃, but below 230 ℃, the thermal effect is not enough, so the relaxation efficiency decreases, making it difficult to achieve the shrinkage rate. If it exceeds 240 ℃, the yarn strength decreases due to pyrolysis and the tar on the roller occurs. It increases and workability falls. The flame-retardant high strength low shrinkage polyester fiber produced in this manner has physical properties of 6.5g / d or more in strength, 6.0% or less in dry heat shrinkage, and LOI of 32 or more by the limit oxygen index method. Polyester according to the present invention having the above physical properties is specifically produced by the following method. A polyester chip having a phosphorus content of 5000-6000 ppm and a TiO ₂ content of 500-3000 ppm and an intrinsic viscosity of 0.85-1.0 is melted at 290-300 ° C. The molten polyester chip is extruded through a spinneret and made into a fiber, and then passed through a pair of gourd rollers. After passing through the stretching roller, the fibrous shape is wound at a speed of 2500 m / min or more after stretching, heat treatment, and relaxation. After being heated with a heating tube directly under the spinneret, the cooled polyester unstretched yarn is drawn between the draw rollers to a total draw ratio of 5.3-5.8 and reduces in-fiber orientation to achieve 11-15% relaxation between the loosening rollers to achieve shrinkage. Applying the rate, the high roller temperature in the relaxation zone is controlled between 230-240 ° C.

Hereinafter, the present invention will be described in more detail with reference to examples, but the examples presented are not intended to limit the scope of the present invention.

The measurement conditions for each analysis item in the results of the following Examples and Comparative Examples are as follows.

(1) strong and faithful

250 mm samples were twisted at 80 times / meter based on ASTM D885, and then measured by tensile testing at a rate of 300 mm / min. The strength obtained by dividing the strength of the measured yarn by the weight of 9,000 m of yarn was determined as the strength of the yarn.

(2) shrinkage

In the test light, the length difference was measured after leaving the sample at 190 ° C. for 15 minutes while applying a load of 0.01 g / d, and the shrinkage force was applied at 0.01 ° C./d at 200 ° C. for 1 minute after holding the sample. Measured.                     

(3) Flame retardant performance

The following equation (1) was determined by the Limit Oxygen Index according to the KS M 3032 method.

--- (1)

--- (One)

        (4) heat of fusion

The heat of fusion of the yarn was measured at 50 ° C to 290 ° C with a heating rate of 20 ° C / min on a 5 mg yarn with Perkin-Elmer DSC-7.

Example 1

A non-stretched yarn was prepared by cooling a melt melted through a spinneret using a flame-retardant polyester solid-state polymerized chip having a TiO2 content of 1000 ppm by copolymerizing a phosphorus compound represented by the following Chemical Formula 2 on a polyester such that the intrinsic viscosity was 0.85 and the phosphorus content was 5000 ppm. Thereafter, the total draw ratio 5.5, the relaxation rate 11%, the temperature of GR4 was stretched-relaxed under the conditions of 230 ℃ and wound at a speed of 2500m / min, the final drawing yarn fineness was 1000 denier.                     

Formula 2

<Examples 2-9, Comparative Examples 1-9>

Viscosity, composition, total draw ratio, GR4 temperature, and relaxation rate of the flame retardant polymer were applied differently, and the other conditions were the same as in Example 1 to prepare polyester fibers. Table 1 shows the manufacturing conditions applied to Examples 1 to 9. In addition, Comparative Examples 1 to 9 are shown in Table 2.

Table 1: Example according to the present invention

Table 2: Comparative Example

In Example 1-9, it was possible to stably produce a flame retardant industrial polyester fiber under conditions that ensure workability by appropriately adjusting the total draw ratio, relaxation zone temperature, and relaxation rate.

In the case of Comparative Example 1, the workability was good, but the physical properties were not sufficient due to the low viscosity of the polymer. In Comparative Example 2, as the spinning temperature was set high due to the high viscosity of the polymer, the physical properties of the polymer were high due to thermal decomposition. Stayed at a low level.

Comparative Example 3 exhibited relatively excellent physical properties due to the low phosphorus content in the polymer, but the flame retardancy could not be secured. On the contrary, Comparative Example 4 exhibited excellent flame retardant properties due to its high phosphorus content but insufficient expression of physical properties.

In Comparative Example 5, since TiO ₂ was not present in the polymer, the strength was low and the shrinkage was very high. Meanwhile, in Comparative Example 6, excessive TiO ₂ was present, resulting in relatively high crystal growth and poor elongation, resulting in poor workability. In Comparative Example 7, the elongation ratio was excessive, resulting in single trimming and trimming. .

In Comparative Example 8, the draw ratio was not low, and the appropriate strength was not expressed. In Comparative Example 9, the relaxation region temperature was too high, resulting in a large amount of tar, resulting in a problem of deterioration in workability.

The flame retardant industrial polyester fiber produced by the present invention is excellent in flame retardancy when used by PVC coating after weaving can be used as a wide range of industrial fibers such as tarpaulin or truck cover.

Claims (6)

In flame retardant polyester fiber, Within the polyester backbone To include a phosphorus-based compound of formula (1), and at the same time comprises TiO2 as a nucleating agent, 1) Strength 6.6 g / d to 7.6 g / d 2) Shrinkage of 4.6 to 5.5% 3) LOI 30 to 34 4) heat of fusion 41.25 to 42.67J / g Polyester fiber characterized by having a physical property of Formula 1

R1 and R2 in Formula 1 above are the same or different radicals having a hydrogen atom or a ω-hydroxy group having 2 to 4 carbon atoms, p is an integer of 1 to 5. The flame retardant polyester fiber according to claim 1, wherein the phosphorus content is 5,000-6,000 ppm on a yarn basis. The flame retardant polyester fiber according to claim 1, wherein the TiO2 is 500-3,000 ppm on a yarn basis. In the method for producing a flame retardant polyester fiber, Within the polyester backbone Solid-phase polymerizing a low-viscosity polyester chip comprising a phosphorus compound of Chemical Formula 1, and simultaneously containing TiO 2 as a nucleating agent; Melting and spinning the solid polymerized polyester chip with a flame retardant polyester chip having an intrinsic viscosity of 0.85-1.1 to produce a cooled solidified non-stretched yarn; Heat-treating the undrawn yarn by directly heating GR4 corresponding to a total draw ratio of 5.3 to 5.8 and a fourth winding roller at a temperature of 230 to 240 ° C .; And The method of producing a flame retardant polyester fiber comprising the step of relaxing the heat-treated undrawn yarn at a relaxation rate of 11-15%.  Formula 1

The method according to claim 4, The phosphorus content of the phosphorus compound is a method for producing a flame retardant polyester fiber, characterized in that 5,000 to 6,000 on a yarn basis. The method according to claim 4, The content of the TiO 2 is a method for producing a flame retardant polyester fiber, characterized in that 500 to 3,000 ppm based on the yarn.

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