Liquid crystal polyester resin composition and molded article made therefrom

Abstract

To provide a liquid crystal polyester resin composition with excellent epoxy adhesion and pull-out resistance, and a molded article made therefrom. [Solution] A liquid crystal polyester resin composition comprising 100 parts by weight of a fully aromatic liquid crystal polyester resin (A), 0.1 to 25 parts by weight of polyetherimide (B), and 0.5 to 6 parts by weight of a copolymer (C) obtained by copolymerizing α-olefin and α,β-unsaturated acid glycidyl esters, wherein the blending ratio of polyetherimide (B) to the copolymer (C) obtained by copolymerizing α-olefin and α,β-unsaturated acid glycidyl esters satisfies formula (P). (B) / (C) ≤ 10 … (P)

Description

Technical Field

[0001] The present invention relates to a liquid crystal polyester resin composition and a molded product made therefrom.

Background Art

[0002] Due to its liquid crystal structure, liquid crystal polyester has excellent properties such as heat resistance, fluidity, and dimensional stability, and is therefore widely used in electrical and electronic components. Among them, parts for camera modules used in smartphones and tablets need to be incorporated into a limited product space due to the increase in the number of parts due to multi-lens configuration. Therefore, space saving is achieved by joining resins together. For joining resins together, for example, a joining method using an epoxy adhesive is adopted. However, since liquid crystal polyester has few reactive groups and poor reactivity with epoxy adhesives, excellent adhesiveness to epoxy resins and the like has been demanded. On the other hand, for parts for sensors mounted on electrical and electronic components, resin-metal composite parts by insert molding are adopted to improve the reliability of the sensors. However, due to impacts and vibrations applied depending on the usage environment of the device, the composite parts may separate, leading to sensor failures. Therefore, excellent pull-out resistance has been demanded. Thus, studies have been made to improve the adhesiveness to epoxy resins and pull-out resistance. For example, resin compositions in which an amorphous resin is blended with liquid crystal polyester (see, for example, Patent Documents 1 to 5), resin compositions in which an olefin-based elastomer is blended with liquid crystal polyester (see, for example, Patent Document 6), and resin compositions in which an olefin-based elastomer and a polyphenylene sulfide resin are blended with liquid crystal polyester (see, for example, Patent Document 7) have been proposed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

[0004] The methods described in Patent Documents 1 to 5 had room for improvement in epoxy adhesion. Furthermore, the high amount of amorphous resin used resulted in reduced pull-out resistance. The methods described in Patent Documents 6 and 7 also had room for improvement in epoxy adhesion. Additionally, the use of only olefin-based elastomers resulted in reduced pull-out resistance.

[0005] The object of the present invention is to provide a liquid crystal polyester resin composition and a molded article made therefrom that can be obtained with improved epoxy adhesion of the liquid crystal polyester resin composition, as well as excellent pulp resistance. [Means for solving the problem]

[0006] As a result of diligent research to solve the above problems, the present inventors have found that molded articles made from a liquid crystal polyester resin composition, which is a mixture of a fully aromatic liquid crystal polyester resin, a polyetherimide, and an olefin-based elastomer in predetermined proportions, exhibit excellent epoxy adhesion and pulp resistance, leading to the present invention.

[0007] In other words, the present invention is as follows: (1) A liquid crystal polyester resin composition comprising 100 parts by weight of a fully aromatic liquid crystal polyester resin (A), 0.5 to 25 parts by weight of polyetherimide (B), and 0.5 to 6 parts by weight of a copolymer (C) obtained by copolymerizing α-olefin and α,β-unsaturated acid glycidyl ester, wherein the blending ratio of polyetherimide (B) to the copolymer (C) obtained by copolymerizing α-olefin and α,β-unsaturated acid glycidyl ester satisfies formula (P). (B) / (C) ≤ 10 … (P) (2) The liquid crystal polyester resin composition according to (1), wherein the all-aromatic liquid crystal polyester resin (A) contains, per 100 mol% of total structural units, 2 to 96 mol% of the following structural units derived from aromatic hydroxycarboxylic acid, 2 to 40 mol% of structural units derived from aromatic diol, and 2 to 40 mol% of structural units derived from aromatic dicarboxylic acid, and further contains at least the following structural unit (II-b) as an aromatic diol and the following structural unit (III-b) as an aromatic dicarboxylic acid.

[0008] [ka]

[0009] (3) A liquid crystal polyester resin composition according to (1) or (2), comprising 10 to 200 parts by weight of filler (C) per 100 parts by weight of all aromatic liquid crystal polyester resin (A). (4) A molded article made from any of the liquid crystal polyester resin compositions described in (1) to (3). (5) The molded article described in (4), wherein the molded article is a molded article having a joint. (6) The molded article according to (4) or (5), wherein the molded article is selected from the group consisting of relays, switches, coil bobbins, camera modules, sensors, and connectors. [Effects of the Invention]

[0010] The liquid crystal polyester resin composition of the present invention can suppress the decrease in pull-out resistance, improve epoxy adhesiveness, and in addition, can obtain a molded product excellent in pull-out resistance. Such a resin composition is particularly suitable for electrical and electronic parts and mechanical parts having joints such as relays, switches, coil bobbins, camera modules, sensors, connectors, and the like.

Brief Description of the Drawings

[0011] [Figure 1] It is a figure showing a test piece for measuring pull-out resistance. [Figure 2] It is a figure showing a test piece for measuring epoxy adhesiveness.

Embodiments for Carrying Out the Invention

[0012] Hereinafter, the present invention will be described in detail.

[0013] <Fully aromatic liquid crystal polyester resin (A)> The fully aromatic liquid crystal polyester resin (A) (hereinafter, may be simply abbreviated as fully aromatic liquid crystal polyester resin) used in the present invention is, for example, a liquid crystal polyester composed of structural units selected so as to form an anisotropic molten phase from aromatic oxycarbonyl units, aromatic dioxy units, aromatic dicarbonyl units, etc., which will be described later. Further, the fully aromatic liquid crystal polyester resin is characterized by not containing structural units generated from aliphatic compounds such as ethylene glycol.

[0014] Next, the structural units constituting the fully aromatic liquid crystal polyester resin will be described.

[0015] Specific examples of the aromatic oxycarbonyl unit include structural units formed from aromatic hydroxycarboxylic acids (I) such as p-hydroxybenzoic acid, m-hydroxybenzoic acid, 6-hydroxy-2-naphthoic acid, etc. From the viewpoint of being able to appropriately control the crystallinity of the wholly aromatic liquid crystal polyester resin and obtaining molded products excellent in epoxy adhesiveness and pull-out resistance, it is preferable to contain structural units formed from p-hydroxybenzoic acid (I-a) and 6-hydroxy-2-naphthoic acid (I-b).

[0016]

Chemical formula

[0017] Specific examples of the aromatic dioxy unit include structural units formed from aromatic diols (II) such as 4,4'-dihydroxybiphenyl, hydroquinone, resorcinol, t-butylhydroquinone, phenylhydroquinone, chloro-hydroquinone, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 3,4'-dihydroxybiphenyl, 2,2-bis(4-hydroxyphenyl)propane, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxydiphenyl sulfone, 4,4'-dihydroxydiphenyl sulfide, 4,4'-dihydroxybenzophenone, etc. From the viewpoint of being able to appropriately control the crystallinity of the wholly aromatic liquid crystal polyester resin and obtaining molded products excellent in epoxy adhesiveness and pull-out resistance, it is particularly preferable to contain structural units formed from 4,4'-dihydroxybiphenyl (II-a) and hydroquinone (II-b). Further, it is more preferable that the aromatic dioxy unit contains at least hydroquinone.

[0018]

Chemical formula

[0019] Specific examples of aromatic dicarbonyl units include structural units derived from aromatic dicarboxylic acids (III), such as terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, 4,4'-diphenyldicarboxylic acid, 3,3'-diphenyldicarboxylic acid, 2,2'-diphenyldicarboxylic acid, 1,2-bis(phenoxy)ethane-4,4'-dicarboxylic acid, 1,2-bis(2-chlorophenoxy)ethane-4,4'-dicarboxylic acid, and 4,4'-diphenyletherdicarboxylic acid. From the viewpoint of being able to appropriately control the crystallinity of the all-aromatic liquid crystal polyester resin and obtain molded products with excellent epoxy adhesion and pultrusion resistance, it is preferable to include structural units derived from terephthalic acid (III-a) and isophthalic acid (III-b). Furthermore, it is more preferable to include at least isophthalic acid as the aromatic dicarbonyl unit.

[0020] [ka]

[0021] Furthermore, in addition to the above structural units, structural units generated from p-aminobenzoic acid, p-aminophenol, etc., may be further present to the extent that they do not impair liquid crystalline properties or other characteristics.

[0022] Specific examples of the all-aromatic liquid crystal polyester resin of the present invention include an all-aromatic liquid crystal polyester resin comprising structural units generated from p-hydroxybenzoic acid, structural units generated from 4,4'-dihydroxybiphenyl and / or hydroquinone, and structural units generated from terephthalic acid and / or isophthalic acid, and an all-aromatic liquid crystal polyester resin comprising structural units generated from p-hydroxybenzoic acid and / or 6-hydroxy-2-naphthoic acid, structural units generated from 4,4'-dihydroxybiphenyl and / or hydroquinone, and structural units generated from terephthalic acid and / or isophthalic acid. Examples include a fully aromatic liquid crystal polyester resin consisting of a ster resin, structural units produced from p-hydroxybenzoic acid, structural units produced from hydroquinone, structural units produced from 4,4'-dihydroxybiphenyl, structural units produced from 2,6-naphthalenedicarboxylic acid, and structural units produced from terephthalic acid; and a fully aromatic liquid crystal polyester resin consisting of a structural unit produced from p-hydroxybenzoic acid, structural units produced from 2,6-dihydroxynaphthalene, structural units produced from 4,4'-dihydroxybiphenyl, and structural units produced from terephthalic acid and / or isophthalic acid.

[0023] From the viewpoint of being able to appropriately control the crystallinity of the all-aromatic liquid crystal polyester resin and obtain molded products with excellent epoxy adhesion and pultrusion resistance, particularly preferred are all-aromatic liquid crystal polyester resins consisting of structural units generated from p-hydroxybenzoic acid, structural units generated from 4,4'-dihydroxybiphenyl, structural units generated from hydroquinone, and structural units generated from terephthalic acid and isophthalic acid, and all-aromatic liquid crystal polyester resins consisting of structural units generated from p-hydroxybenzoic acid, structural units generated from 2,6-dihydroxynaphthalene, structural units generated from 4,4'-dihydroxybiphenyl, structural units generated from hydroquinone, and structural units generated from terephthalic acid and isophthalic acid.

[0024] The raw material monomers constituting each of the above structural units are not particularly limited as long as they have a structure capable of forming each structural unit, but carboxylic acid derivatives such as acylated hydroxyl groups of each structural unit, esterified carboxyl groups of each structural unit, acid halides, and acid anhydrides may be used.

[0025] The total aromatic dioxy units and the total aromatic dicarbonyl units constituting the all-aromatic liquid crystal polyester resin are substantially equimolar. Here, "substantially equimolar" means that the structural units constituting the polymer main chain, excluding the terminals, are equimolar. Therefore, even in configurations where the structural units constituting the terminals are not necessarily equimolar, the requirement of "substantially equimolar" can still be met.

[0026] The liquid crystal polyester resin used in the present invention is preferably a fully aromatic liquid crystal polyester resin containing, per 100 mol% of total structural units, 20 to 96 mol% of the following structural units derived from aromatic hydroxycarboxylic acid (I), 2 to 40 mol% of structural units derived from aromatic diols as aromatic oxycarbonyl units, and 2 to 40 mol% of structural units derived from aromatic dicarboxylic acid.

[0027] The method for calculating the content of each structural unit in the all-aromatic liquid crystal polyester resin of the present invention is as follows. First, the all-aromatic liquid crystal polyester resin is weighed into an NMR (nuclear magnetic resonance) test tube and dissolved in a solvent in which the all-aromatic liquid crystal polyester resin is soluble (for example, a pentafluorophenol / deuterated tetrachloroethane-d2 mixed solvent). Next, the obtained solution is subjected to 1H-NMR spectral measurement, and the content can be calculated from the peak area ratio derived from each structural unit.

[0028] The melting point (Tm) of the all-aromatic liquid crystal polyester resin of the present invention is preferably 220°C or higher, more preferably 270°C or higher, and even more preferably 300°C or higher, from the viewpoint of improving dispersibility with polyetherimide and heat resistance. On the other hand, from the viewpoint of suppressing the deterioration of the liquid crystal polyester resin composition, particularly the olefin-based elastomer (C), during molding and obtaining molded products with excellent epoxy adhesion and pultrusion resistance, the melting point (Tm) of the liquid crystal polyester resin is preferably 360°C or lower, more preferably 350°C or lower, and even more preferably 340°C or lower.

[0029] The melting point (Tm) is measured by differential scanning calorimetry. Specifically, first, the polymer, after polymerization is complete, is heated from room temperature at a rate of 20°C / min to observe the endothermic peak temperature (Tm1). After observing the endothermic peak temperature (Tm1), the polymer is held at a temperature of endothermic peak temperature (Tm1) + 20°C for 5 minutes. Then, the polymer is cooled to room temperature at a rate of 20°C / min. Finally, the polymer is heated at a rate of 20°C / min to observe the endothermic peak temperature (Tm2). The melting point (Tm) refers to this endothermic peak temperature (Tm2).

[0030] The melt viscosity of the all-aromatic liquid crystal polyester resin used in the present invention is preferably 2 Pa·s or higher, more preferably 3 Pa·s or higher, and even more preferably 4 Pa·s or higher, from the viewpoint of obtaining molded articles with excellent epoxy adhesion and pultrusion resistance, as the melt viscosity ratio with polyetherimide described later can be easily controlled to a preferred range. On the other hand, from the viewpoint of fluidity, the melt viscosity of the all-aromatic liquid crystal polyester resin is preferably 100 Pa·s or lower, more preferably 60 Pa·s or lower, and even more preferably 40 Pa·s or lower.

[0031] This melt viscosity was measured using a high-efficiency flow tester at a temperature of the melting point (Tm) of the all-aromatic liquid crystal polyester resin + 20°C and under conditions of a shear rate of 1000 / second.

[0032] The method for producing the all-aromatic liquid crystal polyester resin used in the present invention is not particularly limited and can be produced in accordance with known polycondensation methods for liquid crystal polyesters. Examples of known polycondensation methods for liquid crystal polyesters include the following, using an all-aromatic liquid crystal polyester resin consisting of structural units derived from p-hydroxybenzoic acid, 4,4'-dihydroxybiphenyl, hydroquinone, terephthalic acid, and isophthalic acid.

[0033] (1) A method for producing a fully aromatic liquid crystal polyester resin by a deacetic acid condensation polymerization reaction from p-acetoxybenzoic acid, 4,4'-diacetoxybiphenyl, diacetoxybenzene, terephthalic acid, and isophthalic acid.

[0034] (2) A method for producing a fully aromatic liquid crystal polyester resin by reacting p-hydroxybenzoic acid, 4,4'-dihydroxybiphenyl, hydroquinone, terephthalic acid, and isophthalic acid with acetic anhydride to acetylate the phenolic hydroxyl groups, followed by deacetic acid polymerization.

[0035] (3) A method for producing a fully aromatic liquid crystal polyester resin by a dephenol polycondensation reaction from phenyl p-hydroxybenzoate and 4,4'-dihydroxybiphenyl, hydroquinone, diphenyl terephthalate, and diphenyl isophthalate.

[0036] (4) A method for producing a fully aromatic liquid crystal polyester resin by reacting p-hydroxybenzoic acid and aromatic dicarboxylic acids such as terephthalic acid and isophthalic acid with a predetermined amount of diphenyl carbonate to form phenyl esters, and then adding aromatic dihydroxy compounds such as 4,4'-dihydroxybiphenyl and hydroquinone, followed by a dephenolic polycondensation reaction.

[0037] In particular, (2) a method of producing a fully aromatic liquid crystal polyester resin by reacting p-hydroxybenzoic acid, 4,4'-dihydroxybiphenyl, hydroquinone, terephthalic acid, and isophthalic acid with acetic anhydride to acetylate the phenolic hydroxyl groups, followed by a deacetation polycondensation reaction, is preferred because it is industrially superior in controlling the degree of polymerization of the fully aromatic liquid crystal polyester resin.

[0038] The method for calculating the content of each structural unit in all-aromatic liquid crystal polyester resin is as follows. First, the all-aromatic liquid crystal polyester resin is pulverized, tetramethylammonium hydroxide is added, and the content can be determined by performing a thermal decomposition GC / MS measurement using a Shimadzu GCMS-QP5050A. The content of structural units that were not detected or were below the detection limit is calculated as 0 mol%.

[0039] As a method for producing the all-aromatic liquid crystal polyester resin used in the present invention, it is also possible to complete the polycondensation reaction by solid-phase polymerization. Examples of solid-phase polymerization treatment include the following: First, the polymer or oligomer of the all-aromatic liquid crystal polyester resin is pulverized with a pulverizer. The pulverized polymer or oligomer is heated under a nitrogen atmosphere or under reduced pressure to complete the reaction by polycondensation to the desired degree of polymerization. The above heating can be carried out for 1 to 50 hours in the range of the melting point of the all-aromatic liquid crystal polyester resin -50°C to the melting point of -5°C (for example, 200 to 300°C).

[0040] The polycondensation reaction of all aromatic liquid crystal polyester resins proceeds without a catalyst, but catalysts such as stannous acetate, tetrabutyl titanate, potassium acetate and sodium acetate, antimony trioxide, and metallic magnesium can also be used.

[0041] <Polyetherimide (B)> The liquid crystal polyester resin composition of the present invention is obtained by blending 0.5 to 25 parts by weight of polyetherimide (B) with 100 parts by weight of all aromatic liquid crystal polyester resin (A). If the amount of polyetherimide (B) is less than 0.5 parts by weight, epoxy adhesion and tensile resistance will decrease. From the viewpoint of obtaining a molded product with excellent epoxy adhesion and tensile resistance, 1 part by weight or more is preferred, and 2 parts by weight or more is more preferred. Furthermore, if the amount of copolymer (B) exceeds 25 parts by weight, epoxy adhesion and tensile resistance will decrease. From the viewpoint of obtaining a molded product with excellent epoxy adhesion and tensile resistance, 20 parts by weight or less is preferred, and 15 parts by weight or less is more preferred.

[0042] The liquid crystal polyester resin composition of the present invention contains polyetherimide, but compared to other amorphous resins, polyetherimide has a high amount of anhydride, acid, and amino groups, and interacts with the fully aromatic liquid crystal polyester resin (A) in small amounts. It reacts with copolymers (C) obtained by copolymerizing α-olefins and α,β-unsaturated acid glycidyl esters, as described later, resulting in good adhesive properties and suppression of deterioration of the mechanical properties of the liquid crystal polyester resin composition itself. In particular, the high amount of highly reactive amino groups allows for the production of molded articles with excellent epoxy adhesion and pulp resistance.

[0043] The weight-average molecular weight of the polyetherimide of the present invention is determined by gel permeation chromatography using a polystyrene standard. From the viewpoint of obtaining molded articles with excellent epoxy adhesion and tensile resistance, the weight-average molecular weight of the polyetherimide is preferably 10,000 or more, more preferably 20,000 or more, and even more preferably 40,000 or more. Furthermore, from the viewpoint of obtaining molded articles with excellent epoxy adhesion and tensile resistance, the weight-average molecular weight of the polyetherimide is preferably 80,000 or less, more preferably 70,000 or less, and even more preferably 60,000 or less.

[0044] <Copolymer (C) obtained by copolymerizing α-olefin and glycidyl esters of α,β-unsaturated acids> The liquid crystal polyester resin composition of the present invention comprises 100 parts by weight of a fully aromatic liquid crystal polyester resin (A) and 0.5 to 6 parts by weight of a copolymer (C) obtained by copolymerizing α-olefin (IV-a) and glycidyl ester of α,β-unsaturated acid (IV-b) (hereinafter sometimes abbreviated as copolymer (C)). If the amount of copolymer (C) is less than 0.5 parts by weight, epoxy adhesion and tensile resistance will decrease. From the viewpoint of obtaining a molded product with excellent epoxy adhesion and tensile resistance, 1 part by weight or more is preferred, and 2 parts by weight or more is more preferred. Furthermore, if the amount of copolymer (B) exceeds 6 parts by weight, epoxy adhesion and tensile resistance will decrease. From the viewpoint of obtaining a molded product with excellent epoxy adhesion and tensile resistance, 5 parts by weight or less is preferred, and 4 parts by weight or less is more preferred.

[0045] The liquid crystal polyester resin composition of the present invention contains a reaction product obtained by the reaction of terminal groups of a fully aromatic liquid crystal polyester resin (A) and a polyetherimide (B) component with glycidyl groups of a copolymer (C) component. However, since this reaction product is produced by a complex reaction between polymers, it is not practical to specify its structure. Therefore, the present invention is defined by the components that are included in the formulation.

[0046] The liquid crystal polyester resin composition of the present invention incorporates both polyetherimide (B) and copolymer (C), thereby improving the adhesion between polyetherimide (B) and copolymer (C), and achieving good adhesive properties even with small amounts of components (B) and (C). Furthermore, by using small amounts of components (B) and (C) relative to the fully aromatic liquid crystal polyester resin (A), it is possible to suppress the deterioration of the mechanical properties of the liquid crystal polyester resin composition itself, and in particular, to suppress the deterioration of pulp resistance.

[0047] The liquid crystal polyester resin composition of the present invention is characterized in that the blending ratio of polyetherimide (B) and copolymer (C) satisfies the following formula (P). By satisfying the following formula (P), the adhesive effect of copolymer (C) can be exhibited. By using the blending ratio of formula (P), it is possible to use small amounts of components (B) and (C) relative to the all-aromatic liquid crystal polyester resin (A), thereby suppressing the deterioration of the mechanical properties of the liquid crystal polyester resin composition itself, and in particular suppressing the deterioration of pulp resistance. (B) / (C) ≤ 10 … (P) When the ratio of (B) / (C) exceeds 10, there is an excessive amount of polyetherimide (B) relative to the copolymer (C), significantly reducing the adhesive effect of the copolymer (C), which in turn reduces the epoxy adhesion and pull-out resistance of the molded product. From the viewpoint of obtaining a molded product with excellent epoxy adhesion and pull-out resistance, the (B) / (C) blending ratio is preferably 0.5 or higher, more preferably 1 or higher, even more preferably 2 or higher, and particularly preferably 3 or higher. In this invention, the lower limit of the (B) / (C) blending ratio is 0.08, since the minimum value of (B) is 0.5 parts by weight and the maximum value of (C) is 6 parts by weight. Furthermore, from the viewpoint of obtaining a molded product with excellent epoxy adhesion and pull-out resistance, the (B) / (C) blending ratio is preferably 8 or lower, more preferably 6 or lower, and even more preferably 5 or lower.

[0048] In copolymer (C), α-olefins having 2 to 4 carbon atoms are preferred, specifically ethylene, propylene, and 1-butene, with ethylene being particularly preferred. The glycidyl ester of α,β-unsaturated acid is a compound represented by the following general formula (wherein R is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms), specifically glycidyl acrylate, glycidyl methacrylate, and glycidyl ethacrylate, with glycidyl methacrylate being particularly preferred. From the viewpoint of obtaining a molded product with excellent epoxy adhesion and tensile resistance, the copolymerization amount of α,β-unsaturated acid glycidyl ester (IV-b) is preferably 1% by weight or more, when the total weight of all components constituting copolymer (C) is 100% by weight. More preferably 3% by weight or more. Furthermore, from the viewpoint of obtaining a molded product with excellent epoxy adhesion and tensile resistance, the copolymerization amount of α,β-unsaturated acid glycidyl ester (IV-b) is preferably 20% by weight or less. More preferably 15% by weight or less, even more preferably 10% by weight or less, and particularly preferably 8% by weight or less.

[0049] [ka]

[0050] From the viewpoint of obtaining a molded product with excellent adhesion to epoxy resin and tensile resistance, the copolymerization amount of α-olefin (IV-a) in copolymer (C) is preferably 80% by weight or more, when the total weight of all components constituting copolymer (C) is taken as 100% by weight. More preferably 90% by weight or more. Furthermore, from the viewpoint of obtaining a molded product with excellent epoxy adhesion and tensile resistance, the copolymerization amount of α-olefin (IV-a) is preferably 97% by weight or less, more preferably 95% by weight or less.

[0051] Furthermore, the copolymer (C) may be a copolymer of components (IV-a) and (IV-b) with an additional α,β-unsaturated acid ester (IV-c), from the viewpoint of obtaining molded articles with excellent epoxy adhesion and tensile resistance. (IV-c) may be any α,β-unsaturated acid ester other than the glycidyl ester of the α,β-unsaturated acid which is component (IV-b), but from the viewpoint of obtaining molded articles with excellent epoxy adhesion and tensile resistance, it may also be esters of acrylic acid and methacrylic acid such as methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, and tert-butyl.

[0052] <Filling material (D)> The liquid crystal polyester resin composition of the present invention may also contain a filler (D). From the viewpoint of obtaining a molded product with excellent epoxy adhesion and pultrusion resistance, the amount of filler (D) added per 100 parts by weight of the total aromatic liquid crystal polyester resin is preferably 10 parts by weight or more, more preferably 15 parts by weight or more, and even more preferably 20 parts by weight or more. Furthermore, from the viewpoint of improving fluidity and flexibility, the amount of filler added is preferably 200 parts by weight or less, more preferably 150 parts by weight or less, and even more preferably 100 parts by weight or less.

[0053] The filler (D) is not particularly limited, but examples include fibrous, whisker-like, plate-like, powder-like, and granular fillers. Specifically, fibrous and whisker-like fillers include glass fibers, PAN-based and pitch-based carbon fibers, stainless steel fibers, metal fibers such as aluminum fibers and brass fibers, organic fibers such as aromatic polyamide fibers and liquid crystalline polyester fibers, gypsum fibers, ceramic fibers, asbestos fibers, zirconia fibers, alumina fibers, silica fibers, titanium oxide fibers, silicon carbide fibers, rock wool, potassium titanate whiskers, barium titanate whiskers, aluminum borate whiskers, silicon nitride whiskers, and needle-shaped titanium oxide. Plate-like fillers include mica, talc, kaolin, glass flakes, clay, molybdenum disulfide, and wollastonite. Powder-like and granular fillers include silica, glass beads, titanium oxide, zinc oxide, calcium polyphosphate, and graphite. The filler used in the present invention may have its surface treated with a known coupling agent (e.g., a silane-based coupling agent, a titanate-based coupling agent, etc.) or other surface treatment agent. Furthermore, two or more types of fillers used in the present invention may be used in combination.

[0054] Among these fillers, glass fibers are preferable, particularly in terms of mechanical strength such as tensile strength and flexural strength, and heat resistance. The type of glass fiber is not particularly limited as long as it is used for reinforcing resins, and can be selected from, for example, long fiber type, short fiber type chopped strands and milled fibers.

[0055] In the present invention, weakly alkaline glass fibers are preferred in terms of mechanical strength. In particular, glass fibers with a silicon dioxide content of 50 to 80% by weight are preferred, and glass fibers with a silicon dioxide content of 65 to 77% by weight are more preferred. Furthermore, the glass fibers may be coated or bundled with a coating or bundling agent such as epoxy, urethane, or acrylic; a coupling agent such as silane or titanate; other surface treatment agents; thermoplastic resins such as α-olefin polymers; or thermosetting resins such as epoxy resins.

[0056] <Other Compounds> The liquid crystal polyester resin composition of the present invention may further contain conventional additives selected from antioxidants, heat stabilizers (e.g., hindered phenols, hydroquinones, phosphites, thioethers and their derivatives), ultraviolet absorbers (e.g., resorcinol, salicylates), color inhibitors such as phosphates and hypophosphates, lubricants and mold release agents (e.g., montanic acid and its metal salts, its esters, its half-esters, stearyl alcohol, stearamides and polyethylene waxes), colorants including dyes or pigments, conductive agents or colorants such as carbon black, crystal nucleating agents, plasticizers, flame retardants (e.g., brominated flame retardants, phosphorus-based flame retardants, red phosphorus, silicone-based flame retardants), flame retardant aids, and antistatic agents, as long as they do not impair the effects of the present invention. From the viewpoint of suppressing the deterioration of the mechanical properties of the molded article due to thermal degradation of the copolymer (C) during melt processing, it is preferable to use a heat stabilizer, and among these, it is preferable to use hindered phenols. Alternatively, polymers other than all-aromatic liquid crystal polyester resins can be blended to further impart predetermined properties.

[0057] The method for blending the all-aromatic liquid crystal polyester resin (A) of the present invention with polyetherimide (B), copolymer (C), filler (D), and other additives is not particularly limited. For example, a dry blending method in which polyetherimide (B), copolymer (C), solid filler (D), and other additives are blended with the all-aromatic liquid crystal polyester resin (A), a solution blending method in which the all-aromatic liquid crystal polyester resin, polyetherimide (B), copolymer (C), filler (D), and other liquid additives are blended, a method in which polyetherimide (B), copolymer (C), filler (D), and other additives are added during the polymerization of the all-aromatic liquid crystal polyester resin, or a melt-kneading method in which the all-aromatic liquid crystal polyester resin (A) and polyetherimide (B), copolymer (C), filler (D), and other additives are melt-kneaded, and among these, melt-kneading is preferred.

[0058] Known methods can be used for melt kneading. For example, a Banbury mixer, rubber roll machine, kneader, single-screw or twin-screw extruder can be used to melt knead the all-aromatic liquid crystal polyester resin (A) at a temperature above its melting point and below its melting point + 50°C to obtain a liquid crystal polyester resin composition. A twin-screw extruder is preferred among these. When melt kneading, from the viewpoint of suppressing the deterioration of mechanical properties due to thermal degradation of the copolymer (C), it is preferable to melt knead at 370°C or below, and more preferably at 360°C or below.

[0059] Any of the following methods may be used for mixing: 1) a method in which the whole aromatic liquid crystal polyester resin (A), polyetherimide (B), copolymer (C), filler (D), and other additives are fed in all at once from a main feeder and mixed (all-at-once mixing method); 2) a method in which the whole aromatic liquid crystal polyester resin (A), polyetherimide (B), copolymer (C), and other additives are fed in all aromatic liquid crystal polyester resin (A), polyetherimide (B), copolymer (C), and other additives are fed in all aromatic liquid crystal polyester resin (A), mixed in all aromatic liquid crystal polyester resin (C), and other additives, and then the filler (D) and other additives are added from a side feeder and mixed (side feed method); 3) a method in which a master pellet containing a high concentration of whole aromatic liquid crystal polyester resin (A), polyetherimide (B), copolymer (C), and other additives is prepared, and then the master pellet is mixed with whole aromatic liquid crystal polyester resin (A) and filler (D) to the specified concentration (master pellet method).

[0060] The liquid crystal polyester resin composition of the present invention can be processed into molded articles having excellent surface appearance (color tone), mechanical properties, heat resistance, and flame retardancy by known melt molding methods such as injection molding, injection compression molding, compression molding, extrusion molding, blow molding, press molding, and spinning. Examples of molded articles include injection molded articles, extruded articles, press molded articles, sheets, pipes, various films such as undrawn films, uniaxially oriented films, and biaxially oriented films, and various fibers such as undrawn yarns and super-drawn yarns. Injection molding is particularly preferred from the viewpoint of processability. When melt molding is performed, it is preferable to melt-knead at 370°C or below, and more preferably at 360°C or below, from the viewpoint of suppressing a decrease in mechanical strength due to thermal degradation of the copolymer (C).

[0061] Molded articles obtained by molding the liquid crystal polyester resin or liquid crystal polyester resin composition of the present invention can be used, for example, as flexible printed circuit boards, laminated circuit boards, printed wiring boards and three-dimensional circuit boards used in millimeter-wave and sub-millimeter-wave radars such as personal computers, GPS-equipped devices, mobile phones, and collision avoidance radars, as well as antennas for mobile communication and electronic devices such as tablets and smartphones; lamp reflectors and lamp sockets for LEDs, small cells and microcell components for mobile communication terminal base stations, antenna covers, housings, and automotive sensors. Examples include sensors such as pressure sensors, barometric pressure sensors, tactile sensors, temperature sensors, oxygen sensors, speed sensors, image sensors, CCD sensors, and magnetic sensors; connectors, relay cases and bases; switches, coil bobbins, capacitors; actuator components for camera modules; lens barrel components; mount holder components; CMOS (image sensor) frame components; shutters and shutter bobbin components. In particular, from the viewpoint of obtaining molded products with excellent epoxy adhesion and pull-out resistance, it is especially useful for connectors, relays, switches, coil bobbins, sensors, and camera modules that have adhesive / bonding parts with epoxy resin or metal. [Examples]

[0062] The present invention will be described below using examples, but the present invention is not limited to these examples. In the examples, the composition and properties of the liquid crystal polyester resin were measured by the following methods.

[0063] (1) Composition analysis of liquid crystal polyester resin To 0.1 mg of pulverized liquid crystal polyester resin, 2 μL of 25% methanol solution of tetramethylammonium hydroxide was added, and thermal decomposition GC / MS measurement was performed using a Shimadzu GCMS-QP5050A. The content (mol%) of each structural unit relative to 100 mol% of the total structural units of the polyester resin, and the percentage (%) of the following structural unit (II) derived from aromatic hydroxycarboxylic acid among the total structural units were calculated.

[0064] (2) Measurement of the melting point (Tm) of liquid crystal polyester Using a differential scanning calorimetry (DSC) system (TA Instruments Q200), the endothermic peak temperature (Tm1) observed when the polyester resin was heated from room temperature at a rate of 20°C / min was measured. After holding the sample at Tm1 + 20°C for 5 minutes, it was cooled back to room temperature at a rate of 20°C / min, and then heated again at a rate of 20°C / min. The endothermic peak temperature in the heating curve observed was defined as the melting point (Tm).

[0065] The following are examples of the production of the all-aromatic liquid crystal polyester resin (A) and other liquid crystal polyester resins (a) used in the examples and comparative examples.

[0066] [Manufacturing Example 1] In a 5 L reaction vessel equipped with a stirring blade and distillation tube, 870 parts by weight of p-hydroxybenzoic acid (HBA), 352 parts by weight of 4,4'-dihydroxybiphenyl (DHB), 89 parts by weight of hydroquinone (HQ), 292 parts by weight of terephthalic acid (TPA), 157 parts by weight of isophthalic acid (IPA), and 1278 parts by weight of acetic anhydride (1.07 equivalents of the total phenolic hydroxyl groups) were charged. The mixture was reacted at 145°C for 120 minutes with stirring under a nitrogen gas atmosphere, and then the temperature was raised from 145°C to 360°C over 4 hours. The polymerization temperature was then maintained at 360°C, and the pressure was reduced to 1.0 mmHg (133 Pa) over 1.0 hour. The reaction was continued until a predetermined stirring torque was reached, at which point polymerization was completed. Next, the polymer was extruded in strand form through a nozzle with a 6 mm diameter circular outlet and pelletized with a cutter to obtain a fully aromatic liquid crystal polyester resin (A-1).

[0067] [Manufacturing Example 2] A fully aromatic liquid crystal polyester resin (A-2) was obtained in the same manner as in Example 1, except that the monomer composition was changed to 808 parts by weight of p-hydroxybenzoic acid, 88 parts by weight of 6-hydroxy-2-naphthoic acid (HNA), 229 parts by weight of 4,4'-dihydroxybiphenyl, 161 parts by weight of hydroquinone, 428 parts by weight of terephthalic acid, and 19 parts by weight of isophthalic acid.

[0068] [Manufacturing Example 3] In a 5 L reaction vessel equipped with a stirring blade and distillation tube, 995 parts by weight of p-hydroxybenzoic acid, 126 parts by weight of 4,4'-dihydroxybiphenyl, 112 parts by weight of terephthalic acid, 216 parts by weight of polyethylene terephthalate with an intrinsic viscosity of approximately 0.6 dl / g, and 960 parts by weight of acetic anhydride were charged. The mixture was reacted for 3 hours while raising the temperature from room temperature to 150°C, then from 150°C to 250°C in 2 hours, and from 250°C to 320°C in 1.5 hours. After that, the pressure was reduced to 1.0 mmHg (133 Pa) at 320°C for 1.5 hours, and the reaction was continued until the polymerization was completed when the predetermined stirring torque was reached. Next, the polymer was extruded in strand form through a nozzle with one circular discharge port of 6 mm in diameter, and pelletized with a cutter to obtain other liquid crystal polyester resin (a-3).

[0069] In accordance with (1) and (2) above, the composition and melting point of the liquid crystal polyester resin obtained in each manufacturing example were analyzed. The results are shown in Table 1.

[0070] [Table 1]

[0071] The polyetherimide (B), copolymer (C), epoxy compound, and additives used in each example and comparative example are listed below.

[0072] Polyetherimide (B) and other amorphous resins (b) (B-1): SABIC (Saudi Basic Industries Corporation) “ULTEM1000” (polyetherimide), weight-average molecular weight 55,000 (B-2): SABIC (Saudi Basic Industries Corporation) “ULTEM1040A” (polyetherimide), weight-average molecular weight 30,000 (b-3): Unitika Ltd.'s "U-100" (polyacrylate)

[0073] Copolymer (C) (C-1): BondFirst 2C (ethylene-glycidylmethacin) manufactured by Sumitomo Chemical Co., Ltd. Relate copolymer, ethylene content 94% by weight, glycidyl methacrylate content 6% by weight %)

[0074] Filler (D) (D-1): Milled fiber “EPG40M-10A” manufactured by Nippon Electric Glass Co., Ltd.

[0075] Examples 1-7, Comparative Examples 1-5 In a Toshiba Machine TEM35B twin-screw extruder equipped with a side feeder, the side feeder was installed at section C3 of cylinders C1 (primary feeder side heater) to C6 (die side heater), and a vacuum vent was installed at section C5. Using a screw arrangement with kneading blocks incorporated at sections C2 and C4, the all-aromatic liquid crystal polyester resins (A-1) to (A-2) or other liquid crystal polyester resins (a-3), polyetherimide (B-1), (B-2) or other amorphous resins (b-3), and copolymer (C-1) obtained in each manufacturing example were fed from the primary feeder in the proportions shown in Table 2, and the filler (D-1) was fed from the side feeder in the proportions shown in Table 2. The cylinder temperature was set to the melting point of the liquid crystal polyester resin + 10°C, and the screw rotation speed was set to 200 rpm, and the mixture was melt-kneaded to form pellets. The pellets obtained in each example and comparative example were hot-air dried at 150°C for 3 hours using a hot-air dryer, and then evaluated as described in (3) to (4) below. The results are shown in Table 2.

[0076] (3) Pull-out resistance (pulling strength) A thermoplastic resin composition was injected using a FANUC α30C injection molding machine (manufactured by FANUC Corporation). The resin temperature was set to the melting point of the all-aromatic liquid crystal polyester resin or other liquid crystal polyester resin + 20°C, the mold temperature to 90°C, the injection speed to 120 mm / sec, and the injection pressure to 80 MPa. A 15 × 15 × 30 mm long test piece was held in the mold, and the end of a 5 × 5 × 50 mm long brass rectangular prism was covered with a 5 mm thick, 5 mm long layer of resin. This produced a molded product for tensile testing as shown in Figure 1. The obtained molded product for tensile testing was measured using a Tensilon UTA-2.5T tensile testing machine (manufactured by Orientec Co., Ltd.) at a tensile speed of 10 mm / min. The load at which the metal was pulled out of the resin was determined as the tensile strength, and the number of tests n=20 was measured. Higher strength was evaluated as indicating better tensile resistance.

[0077] (4) Epoxy adhesion (epoxy adhesive strength) Using a FANUC RoboShot α-30C injection molding machine (manufactured by FANUC Corporation), injection molding was performed with the resin temperature set to the melting point of the fully aromatic liquid crystal polyester resin or other liquid crystal polyester resin + 20°C, the mold temperature to 90°C, the injection speed to 120 mm / sec, and the injection pressure to 80 MPa, yielding a dumbbell-shaped test specimen measuring 3.2 mm thick × 6.4 mm × 127 mm long. The test specimen was cut in half, and epoxy adhesive (Sumitomo Bakelite "ECR-9250K") was applied to a bonding area of ​​0.5 cm² as shown in Figure 2. 2 The epoxy adhesive was applied to a thickness of 2 mm, cured at 120°C for 30 minutes, and bonded to obtain molded products for adhesion testing. The obtained molded products for adhesion testing were measured using a Tensilon UTA-2.5T tensile testing machine (manufactured by Orientec Co., Ltd.) at a tensile speed of 10 mm / min, and the load at which the bonded surface peeled off was measured for n=10 tests. In addition, for cases where the bonded surface did not peel off but the base material broke, the value at that time was measured. Epoxy adhesive strength is expressed as the value obtained by dividing the load by the bonded area (MPa). A higher epoxy adhesive strength was evaluated as indicating better epoxy adhesion.

[0078] [Table 2] [Explanation of Symbols]

[0079] V Tensile test direction for pull-out resistance W Resin part X Brass part Y epoxy adhesive Z - A dumbbell-shaped test piece divided into two halves. [Industrial applicability]

[0080] The liquid crystal polyester resin composition of the present invention is suitable for electrical and electronic components such as connectors, relays, switches, coil bobbins, sensors, and camera modules, which have bonding areas with epoxy resins or metals, as it can produce molded products with excellent adhesion to epoxy resins and pull-out resistance.

Claims

1. A liquid crystal polyester resin composition comprising 100 parts by weight of a fully aromatic liquid crystal polyester resin (A), 0.5 to 25 parts by weight of polyetherimide (B), and 0.5 to 6 parts by weight of a copolymer (C) obtained by copolymerizing α-olefin and α,β-unsaturated acid glycidyl ester, wherein the blending ratio of polyetherimide (B) to the copolymer (C) obtained by copolymerizing α-olefin and α,β-unsaturated acid glycidyl ester satisfies formula (P). (B) / (C)≦10… (P)

2. The liquid crystal polyester resin composition according to claim 1, wherein the all-aromatic liquid crystal polyester resin (A) contains, with respect to 100 mol% of total structural units, 20 to 96 mol% of the following structural units derived from aromatic hydroxycarboxylic acid, 2 to 40 mol% of structural units derived from aromatic diol, and 2 to 40 mol% of structural units derived from aromatic dicarboxylic acid, and further comprises at least the following structural unit (II-b) as an aromatic diol and the following structural unit (III-b) as an aromatic dicarboxylic acid. 【Chemistry 1】

3. The liquid crystal polyester resin composition according to claim 1, comprising 10 to 200 parts by weight of a filler (C) per 100 parts by weight of a fully aromatic liquid crystal polyester resin (A).

4. A molded article comprising the liquid crystal polyester resin composition according to any one of claims 1 to 3.

5. The molded article according to claim 4, wherein the molded article is a molded article having a joint portion.

6. The molded article according to claim 4, wherein the molded article is selected from the group consisting of relays, switches, coil bobbins, camera modules, sensors, and connectors.

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