KR100719206B1 - Polyester nanocomposite and a process for preparing thereof - Google Patents

Abstract

The present invention relates to a polyester nanocomposite and a method for producing the same, and more particularly, to a polyester nanocomposite and a method for producing the same, containing from 0.05 to 5% by weight relative to the total weight of the thermally stabilized layered organic mica.

Polyester nanocomposite according to the present invention is excellent in mechanical properties, thermal properties and gas barrier properties can be used in the production of films, containers, engineering plastics, tire cord reinforcement and the like.

Polyester, Nanocomposite, Mica, Organic, Mechanical, Thermal, Dispersion

Description

Polyester nanocomposite and its manufacturing method {Polyester Nanocomposite and A Process for Preparing Thereof}

1 is an X-ray diffraction graph of layered organic mica (organic ME-100) and layered mica (ME-100),

Figure 2 is a thermogravimetric analyzer measurement results photo of organicated ME-100,

3a and 3b show scanning electron micrographs of polyester chips to which 1% by weight and 1% by weight of ME-100 are added in a slurry state of organic ME-100, respectively.

The present invention relates to a polyester nanocomposite and a method for producing the same, and more particularly, to a polyester nanocomposite and a method for producing the same, containing from 0.05 to 5% by weight relative to the total weight of the thermally stabilized layered organic mica.

Efforts have recently been made to obtain nanocomposites with improved functionality by adding various inorganic particles to polymers. These nanocomposites have advantages such as light weight, flexibility and excellent moldability of polymer resins and high strength of inorganic particles. Advantages such as heat stability and chemical resistance can be expressed simultaneously. Among many inorganic particles, many studies have been made to drastically improve the thermal properties, mechanical properties, and gas barrier properties of existing polymers by peeling minerals having a layered structure into nano-size plate-based units and dispersing them in a polymer resin.

Among the minerals having a layered structure, mica has an advantage in that it has a large aspect ratio for interacting with a polymer because of its excellent aspect ratio, and attempts to add it to polyester used in various industrial materials have been actively progressed. 10-0231060, Japanese Patent Laid-Open No. 2000-000144 and Japanese Patent Laid-Open No. 3-041149 describe a method of improving the functionality of a polyester by adding mica to a polyester.

Korean Patent No. 10-0231060 relates to a method of manufacturing fibers by mixing a polymer and mica in a melting step during a spinning process, and Korean Patent Laid-Open No. 2000-000134 discloses a film co-extruded with a polymer mixed with mica powder. Japanese Patent Application Laid-Open No. 3-041149 relates to a method of adding mica powder and a dispersant in an esterification step during polyester production.

However, because the layered particles such as mica are hydrophilic, reaggregation occurs due to a small amount of water when present as a powder, and thus, the mica particles are caused to aggregate again during the polymerization reaction. In order to solve such a problem, Korean Laid-Open Patent Publication No. 2002-0070672 disperses mica particles in two steps, first preparing a slurry, and then introducing the slurry into an esterification step of a polyester polymerization process. In this case, although the particle dispersibility was improved through the preparation of the slurry, in general, in the state of hydrophilic layered inorganic particles, since the affinity with the hydrophobic general polymer is low, it is difficult to increase particle dispersibility and interfacial stability between particles and polymers. When the polymer is processed into a film, a container, a fiber, or the like, stable dispersion of particles is not maintained. Therefore, there is a need to obtain a polymer nanocomposite having excellent particle dispersion state by increasing affinity with a polymer by organicizing inorganic mica.

The present inventors conducted continuous research to solve the above problems, the polyester nanocomposite having excellent mechanical properties, thermal properties and gas barrier properties by adding organically treated mica particles to improve the dispersibility It was found that can be easily prepared to complete the present invention.

Accordingly, it is an object of the present invention to provide a polyester nanocomposite comprising organic mica.

Still another object of the present invention is to provide a method for preparing a polyester nanocomposite containing organic mica.

In order to achieve the above object, the present invention is a polyester characterized in that it contains 0.05 to 5% by weight relative to the total weight of the thermally stabilized layered organic mica by mixing the layered mica with the organic agent capable of ion exchange reaction Provided are nanocomposites.

In addition, the present invention (1). Mixing the layered mica with an organic agent capable of ion exchange reaction to produce a thermally stable layered organic mica; (2) dispersing the layered organic mica prepared above in an organic glycol; (3) it provides a method for producing a polyester nanocomposite comprising the step of polymerizing the layered organic mica dispersed in the polyester resin.

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

The layered inorganic mica used in the polyester nanocomposite according to the present invention is preferably a natural or synthetic mineral having a plate structure having a length and width of 1 μm to 5 mm and a thickness of 8 to 15 A ° aspect ratio of 100 to 7,000. The cation exchange capacity of the layered mica is preferably 50 meq / 100 g to 250 meq / 100 g, and more preferably, a layered mica having a cation exchange capacity of 70 meq / 100 g to 140 meq / 100 g is used.

The layered mica used in the present invention includes vermiculite, muscobite mica, biotite mica, fluorinated mica and the like, but one or more of them can be used, but fluorinated mica is more preferable.

In the present invention, the organic agent used for the organic treatment of the layered mica is not pyrolyzed at a temperature of 300 ℃ or more, phosphonium cation in the form of Onium ions containing an aliphatic or aromatic chain having a high chemical affinity with the polyester monomer. It is preferable that it is a salt, and it has a structure of following formula (1).

[Formula 1]

P ⁺ R _One R ₂ R ₃ R ₄ H ^-

In Formula 1, R ₁ , R ₂ , R ₃ , and R ₄ are aliphatic or aromatic chains having 4 to 40 carbons, and H is a halogen element having an ionic bond with phosphonium.

Dispersed layered mica in water or a co-solvent of water and alcohol to make a suspension, and adding the above-mentioned organic agent capable of ion exchange reaction thereto, and then sufficiently stirring at 25 to 100 ° C. for 1 to 48 hours to replace the phosphonium cation salt. Layered mica is obtained, and after completion of the reaction, by-products of the mixed solution are removed, filtered, and dried to finally produce an organic mica. The organic mica prepared as described above may have excellent thermal stability, high affinity with a polymer, and may prevent a phenomenon in which the interface between the organic-inorganic of the nanocomposite is deformed.

When the organic mica prepared as described above is added to the nanocomposite polymerization reaction, firstly, an appropriate amount of organic glycol is added and stirred with ultrasonic waves to prepare a slurry, wherein the concentration of the slurry is 5 to 80% by weight, more preferably. A level of 10-50% by weight is suitable. When the concentration of the slurry is 80% by weight or more, precipitation and reaggregation of organic mica is caused, and at 5 wt% or less, it is difficult to control the molar ratio of the reactive group, which makes it difficult to proceed with the polymerization reaction through the esterification reaction.

Ultrasonic waves are used in the preparation of the organic mica-organic glycol slurry, wherein ultrasonic waves in the high frequency region having a frequency of about 1 to 10 MHz, which are used for medical devices or nondestructive tests, and washing machines, welding of plastic or metal, etc. Dispersion process was carried out by applying the latter for 5 to 60 minutes among the ultrasonic waves in the low frequency region having a relatively low frequency of 20 kHz to 100 kH, through which the mica with high energy ultrasonic vibrations was effectively crushed. Intercalation through the ion exchange reaction of the organizing agent proceeds efficiently to enable effective dispersion.

The organic glycol solvent used in the present invention may be one or a mixture thereof selected from the group consisting of ethylene glycol, propylene glycol and 1,4-butanediol.

In the present invention, the polyester resin may be one or more selected from the group consisting of polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, and copolymers thereof, and more preferably. Uses polyethylene terephthalate.

In the present invention, after mixing the polyester monomer or oligomer and the slurry of the layered organic mica compound prepared above, to prepare a polyester nanocomposite through a polymerization reaction. The layered organic mica is used in an amount of 0.05 to 5% by weight, more preferably 0.1 to 2% by weight, based on 100 parts by weight of the polyester monomer. In the case of 0.05 wt% or less, the amount of the layered organic mica is small, so that the physical properties are difficult to be improved. In 5 wt% or more, the dispersibility of the layered mica is lowered and the physical properties are reduced.

In the present invention, the polymerization process for preparing the polyester nanocomposite is as follows.

(1) In the slurry reactor, ethylene glycol and terephthalic acid are mixed at a constant molar ratio (0.5 to 2.0) and stirred at room temperature.

(2) The mixture is slowly added to a DE (Direct Esterification) reactor maintained at 250 to 260 ° C. over about 2.5 to 3.5 hours to perform an esterification reaction to prepare an oligomer, wherein an esterification reaction is carried out in the DE reactor. The same amount of oligomer is added beforehand to promote the mixture.

(3) After transferring the oligomer prepared above to a PC (PolyCondensation) reactor maintained at 280 ~ 290 ℃, the layered organic mica compound slurry with ultrasonic waves and dispersed with a stirrer is added and stirred. At this time, the slurry is prepared to add antimony trioxide, a polymerization catalyst, before dispersing into a PC reactor, and to improve dispersibility by using ultrasonic waves when stirring, and to reduce the pressure to 0.5 Torr or less for about 2.5 for polymerization. Polymerize with stirring for ˜3.5 hours.

(4) When the desired intrinsic viscosity (IV = 0.4 ~ 1.0) is reached, the reaction is stopped, and then discharged to prepare a nanocomposite in chip state.

To the polyester nanocomposite according to the present invention, an antioxidant, a heat stabilizer, a colorant, an antistatic agent, a UV absorber, a flame retardant, etc. may be added as necessary.

Hereinafter, the present invention will be described in more detail with reference to examples and comparative examples, but these examples are for illustrative purposes only and should not be construed as limiting the present invention.

The evaluation method of the physical property used in the Example and the comparative example is as follows.

[Property evaluation method]

1) X-ray diffraction experiment: It was used to measure the interlayer distance of the layered organic mica added to the polyester nanocomposite.

2) Thermogravimetric Analyzer (TGA): used to measure the thermal decomposition temperature of the layered organic mica added to the polyester nanocomposite.

3) Scanning electron microscope (SEM): Used to investigate the dispersion characteristics (number and average size) of layered organic mica particles in polymerized polyester nanocomposites.

4) Tensile Strength and Tensile Modulus: The width of the specimen was measured at 13mm, thickness 3.4mm, gauge length 50mm and 50mm / min according to ASTM D638. At this time, the measurement temperature was maintained at 23? And the relative humidity was maintained at 65%, and five specimens were taken to obtain an average value.

5) Impact strength: According to ASTM D256, after the length of the specimen 64mm, width 13mm, thickness 3.4mm, the IZOD strength was measured. At this time, the measured temperature was maintained at 23 ℃, relative humidity was 65%, the average value was obtained by taking 10 specimens.

6) Flexural strength and flexural modulus: The width of the specimen was 13 mm, the thickness was 3.4 mm, and the span length was 55 mm according to ASTM D790, and then measured at a speed of 2 mm / min. At this time, the measured temperature was maintained at 23 ℃, relative humidity was 65%, the average value was obtained by taking five specimens.

7) Heat distortion temperature: The length of specimen was 127mm, width 13mm, thickness 6.4mm and flexural load were measured at 18.6 Kgf / cm ^{2 according} to ASTM D648. At this time, the measured temperature was maintained at 23 ° C. and the relative humidity was 65%, and three specimens were taken to obtain an average value.

 < Example  1>

Dodecane triphenyl phosphonium bromide was prepared by adding 50 g (0.2 mol) of bromododecane and 158 g (0.6 mol) of triphenyl phosphine to 3 L of tetrahydrofuran to react. 40 g of dodecane triphenyl phosphonium bromide prepared above was added to 160 ml of deionized water, 40 ml of ethanol, and 2 ml of concentrated hydrochloric acid to dissolve at 80 ° C. and react to prepare a dodecyl triphenyl phosphonium chloride solution. . Next, 60 g of mica (ME-100) was added to 1.5 L of deionized water, followed by dispersion with ultrasonic waves, and the dodecyl triphenyl phosphonium chloride solution prepared above was added slowly and stirred for 3 hours. Edo rods were used to excite ultrasonic waves using an ultrasonic device. Thereafter, the solids were filtered out, filtered, and the unreacted materials were removed with 1 L of deionized water and 1 L of ethanol, followed by drying to prepare a layered organic mica in powder form.

Next, for polyester polymerization, 8.6 kg of terephthalic acid and 3.8 kg of ethylene glycol were mixed and stirred at room temperature in a slurry reaction tank, and the mixture was gradually added to the DE reactor maintained at 258 ° C. over about 3 hours for esterification. The reaction was carried out to prepare an oligomer. In this case, the same amount of oligomer was added to the DE reactor in advance to promote the esterification reaction.

Half of the oligomer prepared as described above was transferred to a PC reactor maintained at 285 ° C., and then the layered organic mica compound solution prepared above was added and stirred, wherein the layered organic mica compound solution was prepared in 1,000 g of ethylene glycol. 100 g of the layered organic mica and 2.8 g of the antimony trioxide catalyst were prepared, and the ultrasonic wave was stirred for 10 minutes to improve dispersibility. The polymerization reaction was performed under a reduced pressure of 0.5 Torr or less for about 3 hours for the polymerization reaction. Was performed.

After the reaction was stopped when the intrinsic viscosity reached 0.63 dL / g, the physical properties of the polyester nanocomposite prepared by discharging the nanocomposite in the form of a chip were evaluated and the results are shown in Table 1.

< Example  2>

Dodecane triphenyl phosphonium bromide was prepared by adding 50 g (0.2 mol) of bromododecane and 158 g (0.6 mol) of triphenyl phosphine to 3 L of tetrahydrofuran to react. 40 g of dodecane triphenyl phosphonium bromide prepared as described above was added to 160 ml of deionized water, 40 ml of ethanol, and 2 ml of concentrated hydrochloric acid, dissolved at 80 ° C., and reacted to prepare a dodecyl triphenyl phosphonium chloride solution. It was.

Next, 60 g of layered mica (ME-100) was dispersed with ultrasonic waves in 1.5 L of deionized water, and the dodecyl triphenyl phosphonium chloride solution prepared above was added slowly and stirred for 3 hours. After the ultrasonic wave using a rod-type ultrasonic device, the solids were filtered and filtered, and unreacted materials were removed with 1 L of deionized water and 1 L of ethanol, filtered, and then a layered organic mica was prepared without a drying process. .

The physical properties of the polyester nanocomposite prepared in the same manner as in Example 1 using the layered organic mica in the form of a slurry was evaluated and the results are shown in Table 1.

< Example  3>

Except that 30g was applied to the layered organic mica polymerization, the physical properties of the polyester nanocomposite prepared in the same manner as in Example 2 were evaluated and the results are shown in Table 1.

< Comparative example  1>

8.6 kg of terephthalic acid and 3.8 kg of ethylene glycol were mixed and stirred at room temperature in the slurry reactor. The mixture was slowly added to the DE reactor maintained at 258 ° C. over about 3 hours to carry out an esterification reaction to prepare an oligomer. At this time, the same amount of oligomer as the mixture introduced in order to promote the esterification reaction was previously added into the DE reactor.

Half of the oligomer prepared as described above was transferred to a PC reactor maintained at 285 ° C., followed by addition of 2.8 g of antimony trioxide, followed by polymerization under reduced pressure to 0.5 Torr or lower for polymerization. It was. The reaction was stopped when the intrinsic viscosity reached 0.63 dL / g, and then discharged to prepare a polymer in a chip state. The physical properties of the polyester polymer prepared above were evaluated, and the results are shown in Table 1.

< Comparative example  2>

8.6 kg of terephthalic acid and 3.8 kg of ethylene glycol were mixed in a slurry reactor, stirred at room temperature, and the mixture was slowly added to a DE reactor maintained at 258 ° C. over about 3 hours to carry out an esterification reaction to prepare an oligomer. At this time, the same amount of oligomer as the mixture introduced in order to promote the esterification reaction was previously added into the DE reactor.

Half of the oligomer prepared as described above was transferred to a PC reactor maintained at 285 ° C., and then the layered mica mixture was added and stirred. The layered mica mixture was prepared by adding 100 g of unorganized dried mica (ME-100) and 2.8 g of antimonitrioxide to 1,000 g of ethylene glycol, and improved dispersibility by stirring ultrasonic waves for 10 minutes. The polymerization was carried out for about 3 hours under reduced pressure to 0.5Torr or less for the polymerization. The reaction was stopped when the intrinsic viscosity reached 0.63 dL / g, and then discharged to prepare a nanocomposite in a chip state. The physical properties of the polyester nanocomposite were evaluated and the results are shown in Table 1.

TABLE 1

1 is an X-ray diffraction analysis (Rigaku, D / MAX) of the layered organic mica (organization ME-100) used in Examples 1 to 3 and the conventional layered mica (ME-100) used in Comparative Example 2 -3) A shift to the left side of the peak was observed as a graph, and as a result of measuring the d-spacing using the 2θ value at the peak, the organicized ME-100 was about 29.9A at the level of 12.5A ° of ME-100. It can be seen that ° increased. In other words, the interlayer of the layered mica is opened by the organic group, thereby increasing the affinity with the polymer.

Figure 2 shows the results of measuring the thermal decomposition temperature (Td) of the layered organic mica used in Examples 1 to 3 using a thermogravimetric analyzer (TA Instrument, Thermal Analyst 2000). The graph shows that the temperature when the weight loss 2% by weight is a compound having excellent heat resistance at 313 ℃ or more, and thus it can be seen that the material is suitable for the production of a polyester to polymerize at a high temperature of 280 ℃ ~ 290 ℃.

3A and 3B are scanning electron microscope (SEM) photographs of the polyester nanocomposite chip prepared in Example 2 and Comparative Example 2, respectively. FIG. 3A and FIG. 3B are added to the polyester nanocomposite. It can be seen that when the material is an organic layered mica (FIG. 3A), it is more finely and evenly dispersed than when it is a layered mica (FIG. 3B), which is further obtained by comparing the particle dispersibility and the average particle size of Table 1 Specifically compared.

As can be seen through the examples and comparative examples, the present invention provides a simple and fine layered mica dispersed polyester nanocomposite through polymerization with a polyester monomer or oligomer using organicized mica particles. There are advantages that can be provided.

Polyester nanocomposite according to the present invention is excellent in mechanical properties, thermal properties and gas barrier properties can be used in the production of films, containers, engineering plastics, tire cord reinforcement and the like.

Claims (7)

A polyester nanocomposite comprising 0.05 to 5% by weight of a layered organic mica thermally stabilized by mixing the layered mica with an organic agent represented by the following formula (1).  [Formula 1] P ⁺ R ₁ R ₂ R ₃ R ₄ H ^- Wherein R ₁ , R ₂ , R ₃ and R ₄ are each an aliphatic chain or phenyl group consisting of 4 to 40 carbons, at least one of which is a phenyl group, H is a halogen element having an ionic bond with phosphonium. delete (1) mixing the layered mica with an organic agent represented by the following Formula 1 to prepare a thermally stable layered organic mica; (2) dispersing the layered organic mica prepared above in an organic glycol; (3) a method of producing a polyester nanocomposite, comprising the step of polymerizing the layered organic mica dispersed in the polyester resin.  [Formula 1] P ⁺ R ₁ R ₂ R ₃ R ₄ H ^- Wherein R ₁ , R ₂ , R ₃ and R ₄ are each an aliphatic chain or phenyl group consisting of 4 to 40 carbons, at least one of which is a phenyl group, H is a halogen element having an ionic bond with phosphonium. delete The method of claim 3, wherein Step (2) is a method for producing a polyester nanocomposite, characterized in that the layered organic mica in 5 to 80% by weight in organic glycol, and the ultrasonic wave for 1 to 60 minutes to disperse. The method according to claim 3 or 5, The organic glycol solvent is a method for producing a polyester nanocomposite, characterized in that one or two or more selected from the group consisting of ethylene glycol, propylene glycol and 1,4-butanediol. The method of claim 3, wherein The polyester resin of step (3) is one or two or more selected from the group consisting of polyethylene terephthalate, poly trimethylene terephthalate, poly butylene terephthalate, polyethylene naphthalate and copolymers thereof Method for producing a polyester nanocomposite characterized in that.

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