KR100648974B1 - Method for processing polypropylene/polyester fiber composite - Google Patents

Abstract

A method for processing polypropylene/polyester fiber composite is provided to hydrolyze the surface of the polyester fiber by means of basic solution or water. A polyester fiber is immersed into the basic aqueous solution of 0.001 to 1.0 normal for 0.5 to 3.0 hours. The surface of the polyester fiber is treated. Thereafter, the surface-treated polyester and polypropylene are mixed with the weight ratio of 6:4 to 4:6 and then the compatibilizer is added into the mixed solution so that the polypropylene/polyester fiber composite is manufactured. The basic aqueous solution is sodium hydroxide aqueous solution or potassium hydroxide.

Description

Method for manufacturing polypropylene / polyester fiber composites {Method for processing polypropylene / polyester fiber composite}

1 is an electron micrograph of a polypropylene / polyester fiber containing untreated polyester fiber and containing PP-g-MA.

FIG. 2 is an electron micrograph of polypropylene / polyester fiber containing surface treated polyester fiber and containing PP-g-MA. FIG.

The present invention relates to a polypropylene / polyester fiber composite material and a method for manufacturing the same. More specifically, the surface of the polyester fiber is hydrolyzed using a basic solution or water to easily introduce hydroxyl groups on the surface of the fiber, and then commercialized. The present invention relates to a polypropylene / polyester fiber composite material in which a tensile strength is added to improve a tensile strength, and a method of manufacturing the same.

As a method of improving the mechanical properties of the existing polypropylene composite material, as described in Korean Patent Application No. 10-2005-0040493, deformation of the product may occur when glass fiber is used, and in order to improve the plate shape of talc, etc. The use of the inorganic filler is typical, but when the inorganic filler is used in an excessive amount, the tensile strength is rather deteriorated. In order to compensate for this disadvantage, a method of improving compatibility using maleate polypropylene (hereinafter referred to as "PP-g-MA") is used. Compatibilizers such as PP-g-MA react with hydroxyl groups on the surface of the inorganic filler to form hydrogen bonds or covalent bonds, thereby making them compatible with the inorganic filler. However, when a fibrous filler such as glass fiber is added, deformation of the injection molded product occurs due to the orientation of the glass fiber, and the specific gravity of the composite material increases. The high specific gravity of the material increases the amount of material used per volume of the product and increases the price of the product.

Because polyester fibers have a lower specific gravity than glass fibers and have higher tensile strength than polypropylene, adding polyester fibers to polypropylene will result in lower tensile strength than glass fibers but higher tensile strength than polypropylene. As a result, however, polyester fibers have low tensile strength because of their low compatibility with polypropylene. This is because the polypropylene / polyester fiber composite material is not reactive with PP-g-MA due to the chemical properties of the polyester, and even if it is added, the wetting effect of the interface cannot be obtained on the surface of the polyester fiber. Therefore, in order to improve the tensile strength through the chemical reaction with the compatibilizer, it is necessary to introduce a reactive group capable of reacting with the compatibilizer and a pretreatment procedure such as surface treatment of a polyester fiber is required as a method of introducing such a reactive group.

Fibers prepared from polymers, including synthetic fibers, are easily changed to lint during the manufacture of composite materials, such as Korean Patent Application No. 10-2005-0071403. It can only be used in such a way.

In order to effectively utilize polyester fibers having such disadvantages, it is necessary to prepare a composite material at a temperature lower than the melting temperature of the fibrous polyester using a material such as polypropylene or polyethylene having a lower melting temperature than the polyester fiber as a matrix. There is. This is because the shape of the fiber needs to be maintained in order to reflect this property in the mechanical properties of the composite material because the polymer chain is oriented through the stretching process and the fiber strength is very excellent.

Accordingly, the present inventors have no influence of a compatibilizer such as PP-g-MA due to the chemical properties of the polyester fiber, and it is easy to handle the polyester fiber and improve the difficulty of adding a high content. The present invention was completed by discovering that a polypropylene / polyester fiber composite material having improved tensile strength can be prepared by performing a surface treatment to introduce a polar group on the surface of a polyester fiber so as to improve the effect of the compatibilizer. It became.

Accordingly, an object of the present invention is to provide a surface treatment method of introducing a polar group into a polyester fiber by treating a basic solution or water.

It is also an object of the present invention to provide a polypropylene / polyester fiber composite material and a method of manufacturing the same by adding a compatibilizer to the surface-treated polyester fiber to improve mechanical properties including tensile strength.

In order to achieve the above object, the present invention provides a method for introducing a polar group to the polyester fiber surface by treating the polyester fiber with a basic solution.

Looking at the process in detail, the polyester fiber is immersed in a basic aqueous solution of 0.01 to 1.0 normal for 0.5 to 3.0 hours, washed with water and dried at 80 ℃ for 24 hours.

Examples of the basic solution used in the present invention include an aqueous sodium hydroxide solution and an aqueous potassium hydroxide solution.

In the present invention, the polyester fiber may also be surface treated by immersing the polyester fiber in water at 60 to 90 ° C for 24 to 48 hours.

In addition, in the present invention, the masterbatch is prepared by mixing the surface-treated polyester fibers and polypropylene in a weight ratio of 4: 6 to 6: 4 to facilitate the handling of polyester fibers and then adding a compatibilizer to tensile strength And it provides a polypropylene / polyester fiber composite material and a method of manufacturing the improved mechanical properties.

Compatibilizers used in the present invention include PP-g-MA, maleate ethylene-propylene-diene-terpolymer (hereinafter referred to as "EPDM-g-MA") or maleate poly (styrene-b-ethylene-co -Butylene-b-styrene) (henceforth "SEBS-g-MA"). These compatibilizers may be added at 0.5 to 5.0 wt% based on the total weight of the composite material.

Hereinafter, the configuration and effect of the present invention will be described in more detail with reference to Examples and Test Examples. However, these examples are for illustrating the present invention, and the present invention is not limited only to these examples.

Example 1

The polyester fibers were surface treated by immersion in 0.01 normal sodium hydroxide aqueous solution for 3 hours, washed with water, and dried at 80 ° C. for 24 hours. The dried polyester fibers were 30 wt% polyester fiber and 70 wt% homopolypropylene with melt flow index of 0.5 to 60 g / min in a twin screw melter with different rotation ratios up to 170 ° C at a pressure of 6 Kg _f / cm2. Melting and mixing were performed to prepare a polyester fiber masterbatch.

Example 2

In Example 1 was prepared in the same manner as in Example 1 except that the surface treatment by immersion for 0.5 hours using 0.1 normal potassium hydroxide solution instead of 0.01 normal sodium hydroxide solution.

Example 3

In Example 1 was prepared in the same manner as in Example 1, except that the surface treatment for 48 hours in 60 ℃ water instead of 0.01 normal sodium hydroxide solution.

Example 4

The polyester fiber masterbatch prepared in Example 1 was mixed with homopolypropylene having a melt flow index of 10 g / min, and then PP-g-MA was added. At this time, the polypropylene: polyester fiber: PP-g-MA is mixed in a weight ratio of 95: 5: 3.0, 90: 10: 3.0, 85: 15: 3.0, 80: 20: 3.0 and 50: 50: 3.0, respectively It was. The mixture was prepared for the composite material at a temperature of 170 ° C. in a twin screw extruder having an L / D of 40, and the mechanical properties are shown in Table 1 below.

Example 5

The composite material was manufactured in the same manner as in Example 4, except that 3.0 wt% of EPDM-g-MA was added instead of PP-g-MA, and the mechanical properties thereof are shown in Table 1 below.

Example 6

The composite material was manufactured in the same manner as in Example 4, except that 3.0 wt% of SEBS-g-MA was added instead of PP-g-MA, and the mechanical properties thereof are shown in Table 1 below.

Comparative Example 1

The untreated polyester fibers were mixed with homopolypropylene having a melt flow index of 0.5 to 60 g / min, and then PP-g-MA was added. At this time, the polypropylene: polyester fiber: PP-g-MA is mixed in a weight ratio of 95: 5: 3.0, 90: 10: 3.0, 85: 15: 3.0, 80: 20: 3.0 and 50: 50: 3.0, respectively It was. The mixture was prepared for the composite material at a temperature of 170 ° C. in a twin screw extruder having an L / D of 40, and the mechanical properties are shown in Table 1 below.

TABLE 1

Comparison of physical properties of the composite material according to Example 4-6 and Comparative Example 1

Composition (Polypropylene / Polyester Fiber / PP-g-MA) Density (g / cm 3) YS ⁽¹⁾ (kg _f / ㎠) EL ⁽²⁾ (%) FM ⁽³⁾ (kg _f / ㎠) IZOD ⁽⁴⁾ (kg _f .cm / cm) Homo Polypropylene 100/0/0 0.904 379 85 18400 3.6 Comparative Example 1 95/5 / 3.0 0.919 378 28 20300 3.7 90/10 / 3.0 0.932 371 24 20600 3.8 85/15 / 3.0 0.946 359 22 21000 4.0 80/20 / 3.0 0.962 341 15 21300 4.1 50/50 / 3.0 1.054 319 6 21800 4.2 Example 4 95/5 / 3.0 0.921 391 25 19800 4.8 90/10 / 3.0 0.937 408 20 21200 4.7 85/15 / 3.0 0.953 415 16 21500 4.7 80/20 / 3.0 0.968 421 9 21800 4.6 50/50 / 3.0 1.056 433 8 22500 4.5 Example 5 95/5 / 3.0 0.925 385 31 19500 6.8 90/10 / 3.0 0.931 388 28 20800 6.5 85/15 / 3.0 0.956 391 19 21500 6.3 80/20 / 3.0 0.968 397 16 21800 6.2 50/50 / 3.0 1.056 405 10 22100 6.1 Example 6 95/5 / 3.0 0.929 378 36 18900 7.2 90/10 / 3.0 0.936 383 31 19800 7.0 85/15 / 3.0 0.954 389 28 20400 7.0 80/20 / 3.0 0.965 396 21 21500 6.8 50/50 / 3.0 1.055 404 13 21800 6.5

※ ⁽¹⁾ Yield Strength, ⁽²⁾ Elongation,

⁽³⁾ Flexural Modulus, ⁽⁴⁾ notched IZOD impact strength

As described above, the present invention hydrolyzed the surface of the polyester fiber using a basic aqueous solution or water to easily introduce a hydroxyl group on the surface of the fiber, thereby improving the properties of the compatibilizer and the polypropylene / polyester fiber The mechanical properties of the composites were effectively improved. In addition, EPDM-g-MA or SEBS-g-MA also showed effective tensile strength improvement and better impact strength than PP-g-MA. Not only can it be easily made, but it has the advantage of adding a high content of fibers.

Claims (7)

The polyester fibers were immersed in a basic aqueous solution of 0.01 to 1.0 normal for 0.5 to 3.0 hours to surface treat the polyester fibers, and the surface treated polyester fibers and polypropylene were mixed at a weight ratio of 6: 4 to 4: 6. Method for producing a polypropylene / polyester fiber composite material prepared by the addition of a compatibilizer. The method of claim 1, wherein the basic aqueous solution is an aqueous sodium hydroxide solution or an aqueous potassium hydroxide solution. The method of claim 1 wherein the compatibilizer is maleate polypropylene (PP-g-MA), maleate ethylene-propylene-diene-terpolymer (EPDM-g-MA) and maleate poly (styrene-b-ethylene -co-butylene-b-styrene) (SEBS-g-MA) characterized in that the production method characterized in that the selected from the group consisting of. The method of claim 1, wherein the content of the compatibilizer is 0.5 to 5.0 wt% based on the total weight of the composite material. The method according to claim 1, wherein the polyester fiber is immersed in water at 60 to 90 DEG C for 24 to 48 hours instead of the basic solution for surface treatment. A polypropylene / polyester fiber composite material prepared by the method of any one of claims 1 to 5. The composite material according to claim 6, wherein the content of the polyester fiber is 5 to 50 wt% based on the total weight of the composite material.

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