KR100816800B1 - Method for manufacturing nano size-clay containing polypropylene fiber using Nylon 6 and anhydride maleic polypropylene as compatibilizer, and nano size-clay containing polypropylene fiber manufactured by the method - Google Patents

Abstract

The present invention is a method for producing a nano-particle clay-containing polypropylene fiber, characterized in that the excellent heat resistance, flame retardancy, noise and liquid barrier properties, impact resistance by using a uniform dispersion effect of inorganic nanoparticles and nanoparticle phase produced by The present invention relates to a clay-containing polypropylene fiber, and more particularly, to a fiber spinning chip by uniformly mixing / dispersing nanoparticle clay in a thermoplastic resin by a melt compounding method using a twin screw extruder for uniform dispersion of nanoparticle clay. Preparing a; Adding maleic anhydride polypropylene and nylon 6 as a compatibilizer to impart affinity between the nanoclay and the thermoplastic resin in the manufacturing of the spinning chip; Manufacturing fibers by a direct-stretch melt spinning apparatus using the manufactured fiber spinning chip; The present invention relates to a method for producing nanoparticulate clay-containing polypropylene fibers, comprising the steps of producing the fabrics into staple fibers for nonwoven fabric through crimping and cutting, and nanoparticle clay-containing polypropylene fibers produced thereby. The nanoparticle clay-containing polypropylene fiber prepared as described above is excellent in heat resistance, impact resistance, and flame retardancy without deterioration of mechanical properties despite the addition of nano clay, and thus is applied to automotive interior and exterior materials, industrial materials, and construction materials. do.

Nanoparticulate Clay-Containing Polypropylene Fibers, Impact Resistance, Crystal Orientation, Nano Clay, Montmorillonite, Polypropylene, Polyamide

Description

Method for preparing nanoparticulate clay-containing polypropylene fiber using nylon 6 and maleic anhydride-polypropylene as a compatibilizer, and nanoparticulate clay-containing polypropylene fiber produced thereby maleic polypropylene as compatibilizer, and nano size-clay containing polypropylene fiber manufactured by the method}

1 is a transmission electron microscope (TEM) photograph of polypropylene / nylon 6 / clay containing fibers.

2 is a transmission electron microscope (TEM) image of polypropylene / clay containing fibers.

The present invention induces uniform dispersion effect of inorganic nanoparticles using nylon 6 and maleic anhydride polypropylene having good affinity with nanoclay as a compatibilizer, and thus heat resistance, flame retardancy, noise barrier, liquid and gas barrier, impact resistance The present invention relates to a method for producing a nanoparticulate clay-containing polypropylene fiber and to a nanoparticulate clay-containing polypropylene fiber produced by the present invention, and more particularly, to melt using a twin-screw extruder for the purpose of uniform dispersion of the nanoclay. Preparing a fiber spinning chip by uniformly mixing / dispersing nanoparticle clay (montmorillonite) in a thermoplastic resin by a compounding method; Using polypropylene and nylon 6 with maleic anhydride having a graft ratio of 1 to 2 wt% or more as a compatibilizer to impart affinity between the nanoclay and the thermoplastic resin in the manufacturing of the spinning chip; Manufacturing fibers by a direct-stretch melt spinning apparatus using the manufactured fiber spinning chip; It relates to a method for producing a nano-particulate clay-containing polypropylene fiber and a nano-particulate clay-containing polypropylene fiber produced by the step of producing the prepared fiber as a staple fiber for nonwoven fabric through crimping and cutting.

Composite materials using nano-particle clays disperse / peel nano-sized clay particles into thermoplastic organic polymer materials, so that the strength and stiffness, barrier to gas or liquid, abrasion resistance, high temperature stability without impairing impact resistance, endurance and transparency This is a new concept of next generation composite material which is greatly improved. This technology can achieve better physical properties by using inorganic fillers with 3 ~ 5 wt% of nanoparticles less than conventional inorganic filler reinforcement composites, maximizing mechanical properties by peeling and dispersing reinforcement materials to nano size and It is possible to impart new functions such as penetration suppression ability, which is very advantageous in terms of performance / cost. Based on these characteristics, it is attracting worldwide attention as a new material that is expected to be applied to automobiles, electronic information, and civil engineering.

At present, automobile parts and industrial materials include polymer materials such as PP (polypropylene) or TPO (thermoplastic olefin) produced from petrochemical raw materials, composite materials reinforced with inorganic particles and glass fiber, polycarbonate, ABS, etc. have. Among them, polypropylene (PP) has excellent elongation and bending characteristics, but the impact strength is low, so it is used by mixing rubber to improve it. Rubberization has a problem of lowering elongation and bending characteristics of pure resin. have. In order to prevent such deterioration of physical properties, the addition of nanoparticle reinforcement to the polymer resin improves its mechanical properties and flame retardant properties. The above manufacturing technology is a manufacturing technology that generally improves the limit of low mechanical properties of general-purpose polymers to the level of engineering plastics by peeling silica minerals of the silicate layer structure into basic units on a sheet of a nano scale and dispersing them in a polymer resin.

Clay minerals, which are attracting attention as reinforcing nanoparticles, have properties of organic polymers that are difficult to have with inorganic compounds such as swelling, thixotropy, various reactivity with organic compounds, and ion exchange ability, unlike general inorganic crystals or inorganic compound crystals. Therefore, by converting these properties into extreme values, new materials with functions not available in other materials are possible. Clay (montmorillonite (MMT)), which is common in nature among clay minerals, is a mica-like layered silicate mineral belonging to the smectite group, which can increase its volume due to swelling in its crystals. . As such, the clay has a unique property of swelling only by adding water, and thus is suitable as a host layer of an interlayer crosslinking composite material, and thus is important as a new material having various physical properties.

Recently, the weight of automobiles continues to increase due to the diversification of demands of consumers for electronics, luxuryization, safety shoes, etc.As the global environmental pollution problem arises, the company prepares for strengthening the average fuel consumption and automobile emission regulations. A fuel economy improvement is urgently needed. Measures to improve fuel efficiency of automobiles include improvements in the efficiency of engines and drivetrains, and reduction in running resistance. Therefore, research into a change to a lightweight material is required, and as an alternative, the replacement with a polymer composite material is most preferable.

In addition, in order to commercialize this product, fiberization is required through a spinning process, and a method of fiberizing by dissolving or melting a polymer material having fiber forming ability and extruding it through a nozzle of a spinneret to solidify it is called a spinning process. Crystals crystallized in the molten state or the concentrated solution state are mostly bulk structures that are mostly spherical, and thus are hardly oriented. Thus, in order to obtain a fibrous structure, the crystals are stretched under stress to orient the crystals. to be. The degree of orientation and crystallization depends on the rate of spin and temperature and the crystallization capacity of the molecules. In the case of nylon, since the mobility of molecules is good and the molecular drag forming a crystal region is a strong hydrogen bond, the crystallization region is formed during spinning and orientation crystallization is performed by cold drawing. Polymers that crystallize upon spinning, such as nylon, orient the molecules by cold drawing, where necking occurs. Necking is a phenomenon in which a fiber is not uniformly tapered by stretching, but a portion of the fiber is rapidly tapered, and other portions are tapered continuously in this portion, and the whole is stretched thinly. Setting the condition is a problem.

As described above, various researches have been conducted on composite materials using inorganic nanoparticles. However, the degree of dispersion of nanoparticles in polymer resins is important for commercialization of polymer resins such as polypropylene and nylon and inorganic nanoparticles. There is a limit that the dispersion properties vary depending on the ratio of the nanoparticles and the type and amount of the compatibilizer. In addition, polypropylene (PP) and polyamide (PA) have different melting points and melt flow index (MFI) of 163 ^o C and 223 ^o C, respectively. In contrast to polyamide, polyamide has a relatively slower speed than polypropylene. Therefore, it is known that controlling radioactivity is very difficult in manufacturing composite fibers mixed with both, and montmorillonite, a nanoparticle inorganic material. There is little known mass spinning and commercialization.

Therefore, the present invention devised to solve the above problems is a method for improving the problem of cutting during fiber spinning due to poor dispersibility and affinity of nanoparticle clay (montmorillonite) in polymer resin, in particular polypropylene. Nylon 6, which has excellent affinity and dispersibility with nanoparticulate clays, can be used as a compatibilizer to disperse / separate the layered structure of nanoparticulate clays and to further increase uniform affinity and dispersion between polypropylene and nanoparticulate clays. It is an object to use a polypropylene containing 1 to 2% by weight maleic anhydride in parallel as a compatibilizer.

This method was first performed by melt compounding an organic clay (MMT): nylon 6 at a weight ratio of 10 to 15: 85 to 90, thereby inducing uniform dispersion and peeling of nylon 6 of the organic clay. Secondary melt compounding using 20-30 wt% maleic anhydride polypropylene as a compatibilizer for the purpose of preparing clay master batches and increasing the affinity and dispersibility of the prepared nylon 6 / clay master batches with polypropylene To prepare a polypropylene / nylon 6 / maleic anhydride polypropylene / clay containing spin chip containing 3 to 5% by weight clay.

This mixing method overcomes the dispersibility limitations of nanoclays to polypropylene, optimizes the ratio of nylon 6 to nanoclay and the ratio of polypropylene to masterbatch, and furthermore, polypropylene / nylon 6 / clay containing spinning By providing stretching conditions such as draw ratios suitable for fiberization without cutting in large-scale field spinning using chips, crystal orientation is improved, and impact strength, flexural characteristics, and heat resistance are higher than those without using polypropylene / nylon 6 / clay-containing fibers. It is an object of the present invention to provide a method for producing a nanoparticulate clay-containing polypropylene fiber which is excellent in various physical properties such as flame retardancy, and a nanoparticulate clay-containing polypropylene fiber produced thereby.

The present invention for achieving the above object is to prepare a master batch consisting of nylon 6 and clay by melt compounding method using a twin screw extruder after mixing the nanoparticle clay in nylon 6; Pellets composed of masterbatch and clay by secondary melt compounding with a twin-screw extruder by using polypropylene with maleic anhydride having a graft ratio of 1 to 2wt% as a compatibilizer and adding homopolypropylene to the masterbatch prepared in the masterbatch manufacturing step. Manufacturing a (chip); Drying the pellets prepared in the manufacturing step of the pellets in a rotary vacuum oven for 6 hours; Spinning the dried pellets in the drying step to produce fibers; It characterized in that it comprises a step of producing the staple fibers for non-woven fabric through the crimp and cut the prepared fiber.

Preferably in the manufacturing step of the nano-particle clay-containing polypropylene fiber spinning using a direct-stretch melt spinning apparatus spinning die temperature is 230 ~ 240 ℃, the nozzle is characterized by using 250 holes, nozzle diameter 0.8mm .

Also preferably, the draw ratio in the manufacturing step of the nano-particle clay-containing polypropylene fiber is characterized in that 200 ~ 400%.

Another object of the present invention is to provide a nanoparticulate clay-containing polypropylene fiber produced by the method of the nanoparticulate clay-containing polypropylene fiber.

It is still another object of the present invention to provide a nanoparticulate clay-containing polypropylene fiber, wherein the nanoparticulate clay-containing polypropylene fiber is excellent in crystal orientation, heat resistance and impact resistance.

It is another object of the present invention to provide an interior and exterior material for automobiles, which comprises the nanoparticle clay-containing polypropylene fiber.

It is another object of the present invention to provide a building and industrial material, characterized in that it comprises nanoparticle clay-containing polypropylene fibers.

Hereinafter, the configuration of the present invention in more detail with reference to the following.

<Example 1>

Polypropylene / Clay-containing Fiber Manufacturing

Polypropylene (MI = 25, Honam Petrochemical) was used as the thermoplastic polymer resin, where maleic anhydride polypropylene was added as a compatibilizer for the purpose of improving this due to the poor affinity and dispersibility between the nanoparticulate organic clay and polypropylene. Used. In addition, nanoparticle organic clay was used sothern clay (closite 15A).

After drying the maleic anhydride polypropylene and the nanoclay under vacuum at 80 ° C. for 24 hours, the nanoparticulate clay was mixed with the maleic anhydride polypropylene at a weight ratio of 15:85 for 5 minutes at 80 ° C. for 5 minutes. After montmorillonite) is adsorbed onto maleic anhydride polypropylene, it is extruded using a twin screw extruder (DCT-65, L / D = 75), quenched by coolant, dried by hot air, or 3 to 4 mm Cut to size to make a maleic anhydride polypropylene / clay master batch in pellet form. At this time, the melt extruder melt temperature was 230 ~ 240 ^° C. The prepared maleic anhydride polypropylene / clay pellet containing 15% by weight of clay was dried for 24 hours under vacuum at 80 ° C., and then added homopolypropylene, followed by 3 to 5% by secondary melt compounding at a temperature of 230 to 240 ^° C. Pellets for polypropylene / maleic anhydride-polypropylene / clay spinning were prepared containing% nanoparticulate clay.

The pellets were vacuum-dried in a rotary vacuum oven for about 6 hours to prepare nanoparticulate clay-containing polypropylene fibers using a single screw extruder (L / D = 32) type direct melt melt spinning machine. In the spinning condition of the polypropylene / clay pellet according to the present invention, the spinning temperature of the die portion is 230-240 ° C., the nozzle 250 holes, the diameter of the nozzle is 0.8 mm, and 200-400% of the bobbin is directly drawn. Wound up. The wound nanoparticulate clay-containing polypropylene fibers were spun into 12,500 strands, preheated, crimped, dried, and cut into 65 mm to make nonwoven staple fibers. Preheating was hot steam at 100 ^° C., crimped at 65 ^° C. and crimped, and dried at 130 ^° C. Table 1 shows the physical properties according to the content of the nano-particle clay (montmorillonite), and Table 2 shows the change in physical properties with the draw ratio.

 Clay content (%) Denier Tensile strength (g / d) Tensile Modulus (g / d) Elongation (%) Melting Point ( ^o C) Heat of fusion (J / g) 0 9.0 4.19 32.4 163.2 166.5 80.4 3 9.2 4.21 33.2 158.4 169.1 85.6 8.9 4.05 30.8 145.3 170.5 89.4 4 9.3 3.95 28.5 127.5 172.2 91.3 5

Drawing Ratio (%) Denier Tensile strength (g / d) Tensile Modulus (g / d) Elongation (%) Melting Point ( ^o C) Heat of fusion (J / g) 200 11.7 2.47 19.3 272.1 170.7 83.3 300 8.2 3.79 23.9 209.9 171.7 88.5 400 8.0 4.51 32.1 148.7 172.2 91.3

<Example 2>

Manufacture of Polypropylene / Nylon 6 / Clay-containing Fiber

Nylon 6 (MI = 20, Kolon) and Polypropylene (MI = 25, Honam Petrochemical) were used as the thermoplastic polymer resin, where nylon resin is used for the purpose of improving impact strength of polypropylene and dispersibility of nano clay. The maleic anhydride polypropylene was used to further enhance the affinity between the nanoparticulate clay and the polypropylene. In addition, the inorganic particulate organic clay was used sothern clay (closite 15A).

After drying nylon 6 and clay under vacuum at 80 ° C. for 24 hours, 15 wt% of nanoparticle clay was added to nylon 6 and mixed at 80 ° C. for 5 minutes to adsorb powdered clay to nylon 6. A twin screw extruder (DCT-65, L / D = 75) was used to extrude, quench with cool water, dry with hot air, and cut to 3 mm to make pellet-shaped master batches. At this time, the melt extruder melt temperature was 230 ~ 240 ^° C. The prepared nylon 6 / clay pellets containing 15 wt% clay were further dried under vacuum at 80 ° C. for 24 hours, followed by secondary melt compounding at 230-240 ^° C. by adding maleic anhydride polypropylene and homopolypropylene. Polypropylene / maleic anhydride polypropylene / nylon 6 / clay spinning pellets were prepared to contain ˜5 wt% nanoparticulate clay.

The pellets were vacuum dried in a rotary vacuum oven for about 6 hours to prepare fibers using a single screw extruder (L / D = 32) type direct melt melt spinning machine. The spinning conditions of the polypropylene / nylon 6 / clay pellets according to the present invention are the spinning temperature of the die portion is 230 ~ 240 ℃, nozzle 250 holes, the diameter of the nozzle is 0.8 mm, 250-400% Stretched. The wound polypropylene / nylon6 / clay containing fibers were spun into 12,500 strands to preheat, crimp, dry, and cut to 65 mm to produce staple fibers for nonwovens. Preheating was 100 ^° C. hot steam, crimped at 65 ^° C., and dried at 130 ^° C. Table 3 shows the change in physical properties according to the draw ratio.

<Example 3>

Confirmation of Orientation of Nano Clays in Polypropylene Fibers Containing Nanoparticulate Clay

A transmission electron microscope (TEM) measurement was performed to confirm the dispersion state of the clay, which is an inorganic nanoparticle, in the nanoparticulate clay-containing polypropylene fiber prepared in Example 1. Acceleration voltage is 300kv, measured at magnification of 1 million to 2 million.

1 is a transmission electron microscope (TEM) picture after 400% elongation of polypropylene / nylon 6 / clay containing fibers, and FIG. 2 is a picture after 400% elongation of polypropylene / clay containing fibers.

As can be seen in the case of FIG. 1, it is shown that the nanoparticulate clay is uniformly dispersed in the fiber, and the clay is oriented by interlaminar peeling in the fiber axis direction in the nanoparticulate clay-containing polypropylene fiber. The case of FIG. 1 shows that the dispersion and peeling of the clay occurs more uniformly in the fiber axis direction than in FIG. 2. From these results, it can be seen that nylon 6 affects the dispersion and peeling of the clay.

<Example 4>

Impact Strength Measurement of Polypropylene Fibers Containing Nanoparticulate Clay

The impact strength of the polypropylene, polypropylene / nylon 6 composite, polypropylene / clay composite, polypropylene / nylon 6 / clay composite was measured and shown in Table 4. Here, the polypropylene / nylon 6 composite was melt compounded at a 85:15 weight ratio, in the case of the polypropylene / clay composite, the melt content of the nanoparticulate clay was 5 wt%, and the polypropylene / nylon 6 / clay In the case of the composite, a melt compounded composite was prepared by mixing in a weight ratio of 80: 15: 5 and compared with each other.

The impact strength of the polypropylene / nylon 6 composite is about 13% higher than the impact strength of pure polypropylene, about 30% for the polypropylene / clay composite melted with 5 wt% montmorillonite, and polypropylene / An additional 72% increase in impact strength was observed for the nylon 6 / clay composite. This can be interpreted as the impact strength is improved by the inorganic nanoparticles (clay) in the polymer resin absorb the load given from the outside. In addition, in the case of the addition of nylon 6 it can be seen that the value of the impact strength is larger, which is due to the improvement of mechanical properties according to the degree of peeling and dispersion of the clay. Table 4 shows the impact strength measurement results of the nanoparticle clay-containing polypropylene fiber.

Sample Impact Strength (MPa) Polypropylene 5.75 Polypropylene / Nylon 6 6.48 Polypropylene / clay 7.45 Polypropylene / Nylon 6 / Clay 9.89

As described above, the method for producing nanoparticulate clay-containing polypropylene fibers according to the present invention and the nanoparticulate clay-containing polypropylene fibers produced thereby have poor dispersibility of nanoclays (montmorillonite) in a polymer resin (polypropylene) and To ameliorate the problem of fiber spinning due to affinity, a master batch compounded with clay and nylon 6 was prepared and mixed with polypropylene to overcome the limitations of clay's dispersibility to polypropylene and to provide nylon 6 to clay. By optimizing the proportion of polypropylene and the proportion of polypropylene to the master batch, there is an effect of improving dispersibility, flame retardancy and impact resistance. In addition, the present invention provides a polypropylene / nylon 6 / clay composite with a polypropylene / nylon 6 / clay composite to give the stretching conditions, such as the draw ratio suitable for fiberization in large-scale field spinning, and to focus on the weight reduction of automotive parts and the development of high strength composite materials Investigate the spinning process of the fibers and the thermal and mechanical properties of the fibers to select the most appropriate ratios and additives, so that impact strength, high-speed impact strength, flexural properties, heat resistance, and flame retardance are higher than those without polypropylene / nylon 6 / clay-containing fibers. It can be expected to have a functional effect that can be applied to various applications such as automotive interior and exterior materials, building structural materials, electrical and electronic materials that require high strength materials.

Claims (11)

1) Mixing the dried nanoparticulate clay and dried nylon 6 in a weight ratio of clay: nylon 6 = 15-20: 80-85, adsorbing the clay to the nylon 6, and then melting and compounding the nylon 6 / clay-containing pellets Preparing a; 2) After drying the prepared pellets, a mixture of maleic anhydride polypropylene and pure polypropylene is added to the pellet in a weight ratio of polypropylene maleic anhydride: pure polypropylene = 20-40: 60-80, and melt compounded. Preparing a polypropylene / maleic anhydride polypropylene / nylon 6 / clay-containing pellet containing 3 to 5% by weight of clay, based on the total weight; 3) drying the pellets prepared in step 2); 4) spinning the pellets dried in step 3) to produce fibers; And 5) A method for producing nanoparticulate clay-containing polypropylene fibers, comprising the steps of crimping and cutting the fibers to produce staple fibers for nonwoven fabrics. The method of claim 1, Nylon 6 and maleic anhydride polypropylene of step 1) and step 2) is used as a compatibilizer for uniformly dispersing and peeling the nanoparticle clay. The method of claim 1, Polypropylene / maleic anhydride polypropylene / nylon 6 / clay containing pellets of step 2) polypropylene: maleic anhydride polypropylene: nylon 6: weight ratio of clay 45 to 55: 20 to 30: 15 to 20: 3 to 5 A method for producing nanoparticulate clay-containing polypropylene fibers. The method of claim 1, The spinning in step 4) is a method for producing nanoparticle clay-containing polypropylene fiber using a direct-stretch melt spinning apparatus, the spinning die temperature is 230 ~ 240 ℃, the nozzle is 250 holes, the nozzle diameter is 0.8 mm. The method according to claim 1, wherein the spinning in step 4) has a draw ratio of 200 to 400%. Nanoparticulate clay containing polypropylene fiber manufactured by the manufacturing method of any one of the said Claims 1-4. delete An automotive interior and exterior material comprising the nanoparticle clay-containing polypropylene fiber of claim 6 as a main component. delete The building structural material containing the nanoparticle clay containing polypropylene fiber as a main component of Claim 6. delete

Images