KR101783505B1 - Wholly aromatic liquid crystalline polyester resin compound having improved surface properties and impact resistance - Google Patents

Abstract

A wholly aromatic liquid-crystalline polyester resin compound is disclosed. The disclosed wholly aromatic liquid crystalline polyester resin compound has improved surface properties and impact resistance by including an acicular inorganic filler.

Description

TECHNICAL FIELD The present invention relates to a wholly aromatic liquid crystalline polyester resin compound having improved surface properties and impact resistance,

A wholly aromatic liquid-crystalline polyester resin compound is disclosed. More specifically, wholly aromatic liquid-crystalline polyester resin compounds having improved surface properties and impact resistance by including an acicular inorganic filler are disclosed.

The wholly aromatic liquid-crystalline polyester resin is excellent in heat resistance and dimensional stability and has excellent fluidity during melting, and is widely used as a precision injection molding material mainly in the field of electronic devices. In particular, such a wholly aromatic liquid-crystalline polyester resin is a kind of thermoplastic polymer produced by condensation polymerization, which can be kneaded with an inorganic filler such as glass fiber and / or talc and extruded to produce a resin compound. In addition, the resin compound produced as described above can be processed into a product (i.e., an injection molded product) through an injection process.

However, the conventional wholly aromatic liquid-crystalline polyester resin compound has a poor surface, such as a resin peeled off from the surface of the product or fine dust due to the core-sheet structure of the wholly aromatic liquid-crystalline polyester resin contained therein. Here, the "core-sheet structure" refers to a structure in which the liquid crystal is divided into a surface layer in which the liquid crystal is well-oriented and a core layer in which the liquid crystal is not well aligned when the wholly aromatic liquid crystal polyester resin is sectioned, Layer has weak bonding force at the interface therebetween, so peeling and dust generation are easy, and the impact resistance is low. Therefore, such a conventional wholly aromatic liquid-crystalline polyester resin compound is problematic in that it is difficult to apply to high-precision electronic parts such as optical devices which are sensitive to the generation of foreign objects and are required to have impact resistance.

One embodiment of the present invention provides a wholly aromatic liquid crystalline polyester resin compound having improved surface properties and impact resistance by including an acicular inorganic filler.

Another embodiment of the present invention provides an optical apparatus comprising the wholly aromatic liquid-crystalline polyester resin compound.

According to an aspect of the present invention,

An all-aromatic liquid-crystalline polyester resin and an acicular inorganic filler,

The acicular inorganic filler preferably contains, relative to 100 parts by weight of the wholly aromatic liquid-crystalline polyester resin,

5 to 45 parts by weight of a first needle-like inorganic filler having a number average aspect ratio of 2 to 15; And 5 to 40 parts by weight of a second needle-like inorganic filler having a number average aspect ratio of more than 15 to 200. The present invention also provides a wholly aromatic liquid-crystalline polyester resin compound.

The wholly aromatic liquid-crystalline polyester resin may include at least one repeating unit of the following formulas (1) to (6):

(1) a repeating unit derived from an aromatic hydroxycarboxylic acid;

-O-Ar-CO-

(2) a repeating unit derived from an aromatic diol;

-O-Ar-O-

(3) a repeating unit derived from an aromatic diamine;

-HN-Ar-NH-

(4) a repeating unit derived from an aromatic hydroxyamine;

-HN-Ar-O-

(5) a repeating unit derived from an aromatic aminocarboxylic acid; And

-HN-Ar-CO-

(6) a repeating unit derived from an aromatic dicarboxylic acid

-OC-Ar-CO-

In the above formulas (1) to (6), Ar is an aromatic compound in which phenylene, biphenylene, naphthalene or two phenylene are bonded to each other by carbon or an element other than carbon; Or an aromatic compound in which at least one hydrogen of phenylene, biphenylene, naphthalene or an aromatic compound in which two phenylene is bonded to an element other than carbon or carbon is substituted with another element.

The first acicular inorganic filler and the second acicular inorganic filler may each have a length of 30 to 150 탆 and a length of 10 to 20 탆.

The first acicular inorganic filler may include at least one of glass fiber and carbon fiber.

The second acicular inorganic filler may comprise wollastonite.

The wholly aromatic liquid-crystalline polyester resin compound may further include 0 to 20 parts by weight of polyphenylene sulfide (PPS) based on 100 parts by weight of the wholly aromatic liquid-crystalline polyester resin.

According to another aspect of the present invention,

And an optical device including the wholly aromatic liquid-crystalline polyester resin compound.

The optical device may be a camera module.

According to one embodiment of the present invention, the wholly aromatic liquid-crystalline polyester resin compound having improved surface properties and impact resistance can be provided by including the acicular inorganic filler.

According to another embodiment of the present invention, an optical apparatus including the wholly aromatic liquid-crystalline polyester resin compound may be provided.

Fig. 1 is a photograph showing the degree of surface peeling of the wholly aromatic liquid-crystalline polyester resin compound prepared in each of Examples 1 to 7 and Comparative Example 1. Fig.

Hereinafter, the wholly aromatic liquid-crystalline polyester resin compound according to one embodiment of the present invention will be described in detail.

The wholly aromatic liquid-crystalline polyester resin compound according to one embodiment of the present invention includes a wholly aromatic liquid-crystalline polyester resin and an acicular inorganic filler.

In the present specification, the " acicular inorganic filler " means an inorganic filler having a number average aspect ratio of 2 or more.

As used herein, "non-acicular inorganic filler" means an inorganic filler having a number average aspect ratio of less than 2.

The non-needle-like inorganic filler is easily detached from the surface of the liquid-crystalline polyester resin due to its spherical shape or plate-like shape, and has a problem of foreign matter generation and surface peelability. However, since the acicular inorganic filler has a form that can be impregnated on the surface of the liquid crystalline polyester resin, foreign matter generation and surface peelability are low.

The non-acicular inorganic filler may include at least one selected from the group consisting of talc, silica, alumina, calcium carbonate, and barium sulfate.

The wholly aromatic liquid-crystalline polyester resin compound may include 0.01 to 5 parts by weight of the non-needle-like inorganic filler based on 100 parts by weight of the wholly aromatic liquid-crystalline polyester resin.

The acicular inorganic filler preferably comprises 5 to 45 parts by weight of a first acicular inorganic filler having a number-average aspect ratio of 2 to 15 with respect to 100 parts by weight of the wholly aromatic liquid-crystalline polyester resin; And 5 to 40 parts by weight of a second acicular inorganic filler having a number average aspect ratio of more than 15 to 200. [

If the content of the first acicular inorganic filler is within the above range, the first acicular inorganic filler does not come out of the surface of the wholly aromatic liquid-crystalline polyester resin compound while sufficiently exhibiting the effect of reinforcing the physical properties of the first acicular inorganic filler, Occurrence can be prevented.

When the content of the second acicular inorganic filler is within the above range, a wholly aromatic liquid-crystalline polyester resin compound having improved impact resistance while sufficiently exhibiting the surface reinforcing effect of the second acicular inorganic filler can be obtained.

The wholly aromatic liquid-crystalline polyester resin can be produced by the following steps:

(a) synthesizing a wholly aromatic liquid-crystalline polyester prepolymer by condensation polymerization of at least two kinds of monomers; And

(b) synthesizing the wholly aromatic liquid-crystalline polyester resin by solid-phase polycondensing the prepolymer.

The monomer used in the step (a) may be at least one compound selected from the group consisting of an aromatic hydroxycarboxylic acid, an aromatic diol, an aromatic diamine, an aromatic hydroxyamine, and an aromatic aminocarboxylic acid, and an aromatic dicarboxylic acid . ≪ / RTI >

As the synthesis method of step (a), a solution condensation polymerization method or a bulk condensation polymerization method may be used. In order to accelerate the condensation reaction in the step (a), a monomer having increased reactivity (that is, an acylated monomer) which has been pretreated with a chemical substance such as an acylating agent (particularly, an acetylating agent) may be used.

For the solid-phase polycondensation reaction in the step (b), suitable heat should be provided to the prepolymer. Examples of the heat providing method include a method using a hot plate, a method using hot air, and a method using a high temperature fluid. In order to remove the byproducts generated during the solid-phase condensation polymerization, it is possible to purge or remove by vacuum using an inert gas.

The wholly aromatic liquid-crystalline polyester resin may include at least one repeating unit of the following formulas (1) to (6):

(1) a repeating unit derived from an aromatic hydroxycarboxylic acid;

-O-Ar-CO-

(2) a repeating unit derived from an aromatic diol;

-O-Ar-O-

(3) a repeating unit derived from an aromatic diamine;

-HN-Ar-NH-

(4) a repeating unit derived from an aromatic hydroxyamine;

-HN-Ar-O-

(5) a repeating unit derived from an aromatic aminocarboxylic acid; And

-HN-Ar-CO-

 (6) a repeating unit derived from an aromatic dicarboxylic acid

-OC-Ar-CO-

 In the above formulas (1) to (6), Ar is an aromatic compound in which phenylene, biphenylene, naphthalene or two phenylene are bonded to each other by carbon or an element other than carbon; Or an aromatic compound in which one or more hydrogen atoms of phenylene, biphenylene, naphthalene, or an aromatic compound in which two phenylene are bonded to carbon or a non-carbon element is substituted with another element.

The first acicular inorganic filler may have a length of 30 to 150 탆. If the length of the first acicular inorganic filler is within the above range, the first acicular inorganic filler does not come out of the surface of the wholly aromatic liquid-crystalline polyester resin compound while sufficiently exhibiting the effect of reinforcing the physical properties of the first acicular inorganic filler, The surface properties of the wholly aromatic liquid-crystalline polyester resin compound can be improved.

The first acicular inorganic filler may include at least one of glass fiber and carbon fiber.

The first acicular inorganic filler can impart excellent mechanical strength and heat resistance to a wholly aromatic liquid-crystalline polyester resin compound containing the same.

The second acicular inorganic filler may have a length of 10 to 20 mu m.

The second acicular inorganic filler may comprise wollastonite.

The second acicular inorganic filler can impart excellent dimensional stability, impact resistance and surface properties to the wholly aromatic liquid-crystalline polyester resin compound containing the same.

The wholly aromatic liquid-crystalline polyester resin compound may further include 0 to 20 parts by weight of polyphenylene sulfide (PPS) based on 100 parts by weight of the wholly aromatic liquid-crystalline polyester resin.

When the content of the polyphenylene sulfide (PPS) is within the above range, the properties of the wholly aromatic liquid-crystalline polyester resin and the polyphenylene sulfide (PPS) do not appear and the surface properties of the wholly aromatic liquid- Can be improved.

For example, the wholly aromatic liquid-crystalline polyester resin compound may further include 4 to 20 parts by weight of polyphenylene sulfide (PPS) based on 100 parts by weight of the wholly aromatic liquid-crystalline polyester resin.

The wholly aromatic liquid-crystalline polyester resin compound may further include a pigment such as carbon black, which is a black pigment, as an additive. The content of the pigment may be 0.5 to 5 parts by weight based on 100 parts by weight of the wholly aromatic liquid-crystalline polyester resin.

Wherein said wholly aromatic liquid crystalline polyester resin compound comprises 100 parts by weight of wholly aromatic liquid crystalline polyester resin, 5 to 45 parts by weight of said first acicular inorganic filler, 5 to 40 parts by weight of said second acicular inorganic filler, By weight to 20 parts by weight or less to prepare a resin composition, and drying and then melt-kneading the resin composition.

For such melt kneading, a twin-screw extruder, a batch kneader or a mixing roll may be used. In particular, when the melt-kneading is performed using a twin-screw extruder, the barrel temperature of the extruder can be maintained at 310 ° C to 330 ° C. Here, the barrel of an extruder is also referred to as a cylinder as a portion for melting, kneading, and transporting an extruded material (i.e., a resin composition). A screw is mounted in the barrel so that the extruded raw material is fed forward in accordance with the rotation of the screw. At the same time, the extruded raw material is melted due to heat conducted from an external heat source through the barrel wall surface.

Further, one embodiment of the present invention provides an optical apparatus including the wholly aromatic liquid-crystalline polyester resin.

The optical device may be, for example, a camera module. As used herein, the term " camera module " refers to a built-in camera lens or holder of a sensor such as a mobile phone, a tablet notebook or the like.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these embodiments.

Example

Example  1 to 10 and Comparative Example  1-3

(1) Selection of wholly aromatic liquid-crystalline polyester resin (LCP)

SELCION KD Grade wholly aromatic polyester resin (HBA / BP / IPA / TPA = 60/20 / 13.5 / 6.5) of Samsung Fine Chemical Co., Ltd. was used. Where HBA is parahydroxybenzoic acid, BP is 4,4'-biphenol, IPA is isophthalic acid and TPA is terephthalic acid.

(2) Production of wholly aromatic liquid-crystalline polyester resin compound

(Length: 75 μm, number average aspect ratio: 7.5, Sungjin fiber, MGF 75NL), wollastonite (WN) (length: 14 to 20 PPS-HB Grade, Melt Index (MI): 330 (5kg load and 315 ° C), and the weight of the polyimide resin (PPS-HB Grade, number average aspect ratio: 15, Tongyang Materials Industry, YW-38AJ), polyphenylene sulfide ), Talc (TA: length: 11 μm, Dongyang Materials Industry, ETA # 400) and carbon black (CB) (KIB Japan, HIBLACK 30L) were mixed in an automatic mixer (L / D: 40, diameter: 25 mm) (W & P, ZSK 25 P8.2E) at 150 ° C. for 4 hours using a drying oven To prepare a wholly aromatic liquid-crystalline polyester resin compound. During the melt kneading, a by-product was removed by applying a vacuum to the twin screw extruder.

LCP
(Parts by weight) PPS
(Parts by weight) GF
(Parts by weight) TA
(Parts by weight) WN
(Parts by weight) CB
(Parts by weight) Example 1 100 0 7.27 0 36.34 1.74 Example 2 100 0 14.53 0 29.07 1.74 Example 3 100 0 21.80 0 21.80 1.74 Example 4 100 4.56 22.80 0 22.80 1.82 Example 5 100 7.84 23.51 0 23.51 1.88 Example 6 100 11.33 24.27 0 24.27 1.94 Example 7 100 17.01 25.51 0 25.51 2.04 Example 8 100 17.01 42.52 0 8.50 2.04 Example 9 100 21.13 26.41 0 26.41 2.11 Example 10 100 0 36.34 0 7.27 1.74 Comparative Example 1 100 0 7.27 36.34 0 1.74 Comparative Example 2 100 0 0 0 43.60 1.74 Comparative Example 3 100 0 43.60 0 0 1.74

Evaluation example  1: Surface peel evaluation

Each of the wholly aromatic liquid-crystalline polyester resin compounds prepared in Examples 1 to 7 and Comparative Example 1 was used to prepare injection-molded specimens (13 mm wide x 130 mm wide x 3 mm thick) according to ASTM D790, A Scotch tape (3M company) (20 mm x 200 mm in length) was attached, and the scotch tape was peeled at a rate of 5 cm / min using a UTM machine (INSTRON, 5569). One side of the peeled scotch tape was photographed, and the results are shown in Fig. (A), (b), and (d) are the same as those in the first, second, and third embodiments, respectively. f) is Example 6, (g) is Example 7, and (h) is Comparative Example 1.

Referring to FIG. 1, the wholly aromatic liquid-crystalline polyester resin compound prepared in Examples 1 to 7 was significantly reduced in surface foreign matter than the wholly aromatic liquid-crystalline polyester resin compound prepared in Comparative Example 1. In particular, it can be confirmed that the wholly aromatic liquid-crystalline polyester resin compound prepared in Examples 4 to 7 including polyphenylene sulfide (PPS) is suitable for optical instruments which are sensitive to the generation of foreign matter because there are few foreign matters on the surface.

Evaluation example  2: Property evaluation

The flexural strength, the weld strength, the dust amount and the crack amount of each of the wholly aromatic liquid-crystalline polyester resin compounds prepared in Examples 1 to 10 and Comparative Examples 1 to 3 were measured, and the results are shown in Table 2 below.

(Flexural strength)

The flexural strength of each of the above-mentioned all-aromatic liquid-crystalline polyester resin compounds was measured according to ASTM D790.

(Weld strength)

Each of the wholly aromatic liquid-crystalline polyester resin compounds prepared in Examples 1 to 10 and Comparative Examples 1 to 3 was injection-molded into a welded structure having a width of 13 mm x 70 mm x 1 mm and a weld line formed at the center of the specimen After the strength specimens were prepared, the weld strength was measured according to ASTM D790.

 (Amount of dust and amount of crack)

Each of the wholly aromatic liquid-crystalline polyester resin compounds prepared in Examples 1 to 10 and Comparative Examples 1 to 3 was injection-molded, and the plate-like specimen (shape of a card socket of Samsung Fine Chemicals Co., Ltd., weight: 136 mg, size: 300 pieces of the specimens were put into a vial bottle (50 ml), and the vial bottle was swung in an automatic mixer (Jeil Industrial Instrument) for 3 hours to induce friction between specimens to generate dust. Then, isopropanol washes away the dust on the wall surface of the vial and the specimen, and the isopropanol containing the dust was filtered with a filter paper (pore size: 10 μm, weight: 500 mg) to collect the dust, And dried at 150 DEG C for 30 minutes in a drying oven (manufactured by Shing PLANT), and then the weight of the dust was measured. The dust amount was calculated by calculating the weight of the dust with respect to the total weight of the 300 specimens (total 48.80 g) as a percentage, and the results are shown in Table 2. After the dust amount generation test, the ratio of the specimen in which cracks occurred in 300 specimens was measured by visual observation. The results are shown in Table 2 below.

Flexural strength
(MPa) Weld strength
(MPa) Amount of dust
(wt%) Crack amount
(%) Example 1 133 24.8 0.10 2.3 Example 2 133 25.7 0.14 1.7 Example 3 135 27.5 0.16 1.0 Example 4 130 25.7 0.15 0.9 Example 5 126 27.4 0.15 1.0 Example 6 120 27.4 0.14 1.1 Example 7 118 27.3 0.13 1.0 Example 8 123 27.3 0.15 0.9 Example 9 115 27.2 0.12 1.3 Example 10 145 28.3 0.18 0.8 Comparative Example 1 140 24.8 0.17 10.0 Comparative Example 2 131 23.5 0.09 3.8 Comparative Example 3 150 28.5 0.29 0.7

Referring to Table 2, the wholly aromatic liquid-crystalline polyester resin compound prepared in Examples 1 to 10 was excellent in both the strength of the weld, the amount of dust, and the amount of the cracks, showing improved surface characteristics and impact resistance as compared with Comparative Examples 1 to 3. In Comparative Examples 1 and 2, the amount of dust is small, but the weld strength is lower and the amount of cracks is remarkably high as compared with Examples 1 to 10, which is disadvantageous in that the impact resistance is poor.

Therefore, the wholly aromatic liquid-crystalline polyester resin compound according to one embodiment of the present invention is excellent in surface properties as well as impact resistance, and can be used for high-precision electronic parts such as optical devices that are sensitive to the generation of foreign matter and require impact resistance have.

Although the present invention has been described with reference to the drawings and embodiments, it is to be understood that various modifications and equivalent embodiments may be made by those skilled in the art. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

Claims (8)

An all-aromatic liquid-crystalline polyester resin and an acicular inorganic filler,
The acicular inorganic filler preferably contains, relative to 100 parts by weight of the wholly aromatic liquid-crystalline polyester resin,
7.27 to 36.34 parts by weight of a first sheet of inorganic filler having a number average aspect ratio of 2 to 15 and a length of 30 to 150 mu m; And
7.27 to 36.34 parts by weight of a second acicular inorganic filler containing wollastonite having a length of 10 to 20 占 퐉. The method according to claim 1,
The wholly aromatic liquid-crystalline polyester resin is a wholly aromatic liquid-crystalline polyester resin compound containing at least one repeating unit represented by any one of the following formulas (1) to (6)
(1) a repeating unit derived from an aromatic hydroxycarboxylic acid;
-O-Ar-CO-
(2) a repeating unit derived from an aromatic diol;
-O-Ar-O-
(3) a repeating unit derived from an aromatic diamine;
-HN-Ar-NH-
(4) a repeating unit derived from an aromatic hydroxyamine;
-HN-Ar-O-
(5) a repeating unit derived from an aromatic aminocarboxylic acid; And
-HN-Ar-CO-
(6) a repeating unit derived from an aromatic dicarboxylic acid
-OC-Ar-CO-
In the above formulas (1) to (6), Ar is an aromatic compound in which phenylene, biphenylene, naphthalene or two phenylene are bonded to carbon or an element other than carbon; Or an aromatic compound in which at least one hydrogen of phenylene, biphenylene, naphthalene or an aromatic compound in which two phenylene is bonded to an element other than carbon or carbon is substituted with another element. delete The method of claim 1, wherein
Wherein the first acicular inorganic filler comprises at least one of glass fiber and carbon fiber. delete The method according to claim 1,
Further comprising polyphenylene sulfide (PPS) in an amount of 0 to 20 parts by weight based on 100 parts by weight of the wholly aromatic liquid-crystalline polyester resin. An optical device comprising a wholly aromatic liquid-crystalline polyester resin compound according to any one of claims 1, 2, 4 and 6. 8. The method of claim 7,
Wherein the optical device is a camera module.

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