WO1999024511A1

WO1999024511A1 - Liquid-crystal polymer molding

Info

Publication number: WO1999024511A1
Application number: PCT/JP1998/005019
Authority: WO
Inventors: Tomoyuki Aketa; Kazuhito Kobayashi; Yasuyuki Fukute
Original assignee: Polyplastics Co., Ltd.
Priority date: 1997-11-12
Filing date: 1998-11-09
Publication date: 1999-05-20
Also published as: JPH11199761A

Abstract

A liquid-crystal polymer molding produced by melt processing a liquid-crystal polymer composition comprising 100 parts by weight of a liquid-crystal polymer (A) and 0.001-10 parts by weight of at least one compound (B) selected from among primary phosphates, pyrophosphates and borates, having an excellent heat resistance, and scarcely undergoing surface blistering even when subjected to high-temperature heat treatment such as soldering or infrared reflow.

Description

Description Liquid crystal polymer moldings Field of the invention:

The present invention relates to a liquid crystal polymer molded article which does not easily generate a prister on its surface even when subjected to a high-temperature heat treatment such as solder welding or IR reflow and has excellent heat stability. Conventional technology:

Liquid crystalline polymers are often used for materials that require heat treatment at high temperatures because of their high melting point, excellent melting point, and excellent fluidity. If the molded product is left in high-temperature air or liquid for a long period of time, problems such as blisters or blisters on the surface may occur. This phenomenon occurs because the decomposition gas generated when the liquid crystalline polymer is in the molten state is brought into the molded product, and when the high-temperature heat treatment is performed, the gas expands and the surface of the molded product softened by heating. It rises and appears as a blister. Methods for reducing the generation of such blisters include evacuating the material from the vent hole during melt extrusion and preventing the material from staying in the molding machine for a long time during molding. It was narrow and not practical, and its effect was not enough.

In addition, since the liquid crystalline polymer has a high melting point, high temperature treatment is required even at a compound temperature such as a filler or a molding temperature. However, under such high-temperature conditions, known organic heat stabilizers such as hindered phenol and organic phosphoric acid ester may be decomposed, or may be melt-kneaded or molded with the polymer or after molding. Did not show the effect as a stabilizer. Even under these conditions, no stabilizer with melt heat stability and heat stability has been found yet. The discovery was awaited.

In view of the above problems, the inventors of the present invention have excellent heat stability such that blisters do not occur even when subjected to high-temperature heat treatment under a slight change in molding conditions, and that their mechanical properties are less reduced even at high temperatures. Intensive investigations and studies to obtain liquid crystalline polymer molded products with improved properties, that is, improved high-temperature heat treatment properties, resulted in one or more selected from primary phosphates, pyrophosphates, and borates. Molding force of liquid crystalline polymer composition containing the compound of the formula (1) Blisters did not occur and did not occur over a wide range of molding conditions, and the present invention was completed. DISCLOSURE OF THE INVENTION That is, the present invention relates to (A) 100 parts by weight of a liquid crystalline polymer resin, and (B) one or two or more compounds selected from primary phosphates, pyrophosphates and borates at 0.001%. An object of the present invention is to provide a molded article having improved heat stability which is melt-processed using a liquid crystalline polymer resin composition containing up to 10 parts by weight.

Alternatively, the present invention provides (A) 100 parts by weight of a liquid crystalline polymer and (B) 0.001 to 10 parts by weight of at least one compound selected from the group consisting of primary phosphates, lipophosphates and borates. It is a molded article with improved high-temperature heat treatment properties obtained by melt-processing a liquid crystal polymer composition containing the same. DETAILED DESCRIPTION OF THE INVENTION Hereinafter, the resin composition components constituting the molded article of the present invention will be described in detail. The phosphate as the component (B) used as an essential component in the molded article of the present invention is limited to only the first phosphate and pyrophosphate, and the second and third phosphates, metaphosphate, trimetaphosphate Alkali metal salts or alkaline earth metal salts of condensates such as acids or polyphosphoric acids have no effect on blister and heat stability. On the other hand, examples of borate salts include metal salts of boric acid compounds such as orthoboric acid, metaboric acid and tetraboric acid, and metal salts of alkali metal, as well as ammonium salts of boric acid.

Among them, salts of orthophosphoric acid and orthoboric acid are highly effective and are preferably used. These primary phosphate, pyrophosphate and borate can be used in combination. Commercial products can be used for these primary phosphates, pyrophosphates and borates. The primary phosphate, pyrophosphate and borate used are not particularly limited in particle size, but the smaller the particle size, the better the effect and the smaller the particle size, the better. .

These compounds can be added to the liquid crystalline polymer by kneading using a general single-screw or twin-screw extruder, extruding into pellets, and mixing and molding some of the necessary components as a masterbatch. A method of pulverizing, mixing and melt-extruding a part or all of the liquid crystalline polymer to improve the dispersion and mixing of the components, and adding the liquid crystalline polymer to a molding pellet of the liquid crystalline polymer composition during molding. Any method is possible.

In the present invention, the compounding amount of the component (II) is 0.001 to 10 parts by weight, preferably 0.01 to 5 parts by weight, particularly preferably 0.01 to 1 part by weight, based on 100 parts by weight of the liquid crystal polymer (II). If the amount is less than 0.001 part by weight, the effect of suppressing blister generation intended by the present invention is poor, and if it exceeds 10 parts by weight, excessive primary phosphate, pyrophosphate, and borate may cause excessive physical properties and moldability of the composition. Make you worse.

The liquid crystalline polymer (Α) used in the present invention is a melt-processable polymer and has a property in which polymer molecular chains take a regular parallel arrangement in a molten state. The state in which the molecules are arranged in this manner is often referred to as a liquid crystal state or a nematic phase of a liquid crystalline substance. Such polymer molecules are generally elongated, flattened, fairly rigid along the long axis of the molecule, and typically have multiple chain-extended bonds, either coaxial or parallel. Of a polymer having

The properties of the anisotropic molten phase can be confirmed by a conventional polarization inspection method using an orthogonal polarizer. More specifically, the confirmation of the anisotropic molten phase can be performed by using a Leitz polarizing microscope and observing the molten sample placed on a Leitz hot stage at a magnification of 40 times under a nitrogen atmosphere. The polymer of the present invention, when inspected between crossed polarizers, transmits polarized light even when in the melt resting state, and exhibits optical anisotropy. Liquid crystalline polymers suitable for use in the present invention tend to be substantially insoluble in common solvents and are therefore unsuitable for solution processing. However, as already mentioned, these polymers can be easily processed by conventional melt processing methods. The liquid crystalline polymer suitable for use in the present invention is preferably an aromatic polyester or an aromatic polyester amide, and a preferred example is an aromatic polyester or a polyester partially containing the aromatic polyester amide in the same molecular chain. is there.

Particularly preferred are liquid crystalline aromatic polyesters having at least one compound selected from the group consisting of aromatic hydroxycarboxylic acids, aromatic hydroxyamines, and aromatic diamines as constituents, and liquid crystalline aromatic polyester amides. It is.

More specifically,

1) Polyester consisting mainly of one or more aromatic hydroxycarboxylic acids and their derivatives

2) Mainly

a) one or more aromatic hydroxycarboxylic acids and derivatives thereof and b) one or more aromatic dicarboxylic acids, alicyclic dicarboxylic acids and derivatives thereof

c) polyester comprising at least one or more aromatic diols, alicyclic diols, aliphatic diols and derivatives thereof

3) Mainly a) one or more aromatic hydroxycarboxylic acids and derivatives thereof and b) one or more aromatic hydroxyamines, aromatic diamines and derivatives thereof.

c) Polyester amide comprising one or more aromatic dicarboxylic acids, alicyclic dicarboxylic acids and derivatives thereof

Mainly)

a) one or more aromatic hydroxycarboxylic acids and derivatives thereof and b) one or more aromatic hydroxyamines, aromatic diamines and derivatives thereof.

c) one or more aromatic dicarboxylic acids, alicyclic dicarboxylic acids and their derivatives

d) Polyester amide comprising at least one or more aromatic diols, alicyclic diols, aliphatic diols and derivatives thereof

Is mentioned.

Further, a molecular weight modifier may be used in combination with the above constituents as necessary.

Preferred examples of specific compounds constituting the liquid crystalline polymer of the present invention include 2,6-naphthalenedicarboxylic acid, 2,6-dihydroxynaphthalene, 1,4-dihydroxysinaphthalene, and 6-hydroxy-21-naph. Naphthalene compounds such as tonic acid; biphenyl compounds such as 4,4'-diphenyldicarboxylic acid and 4,4'-dihydroxybiphenyl; represented by the following general formula (I), (II) or (III) Compound to be used;

(However, a group selected from X alkylene (Cl to C4), alkylidene, -0-, -SO-, -SO2-, -S-, -CO-

Y: a group selected from-(CH2) n- (n = 1 to 4) and -0 (CH2) n〇- (n = 1 to 4)) p—hydroxybenzoic acid, terephthalanolic acid, hydroquinone, p —Pheno-substituted benzene compounds such as aminophenol and P-phenylenediamine, and their nucleus-substituted benzene compounds (substituents are selected from chlorine, bromine, methyl, phenyl, and 1-phenylenoethyl); isophthalic acid And meta-substituted benzene compounds such as resorcinol.

Further, the liquid crystalline polymer used in the present invention may be a polyalkylene terephthalate which does not partially show an anisotropic molten phase in the same molecular chain, in addition to the above-mentioned constituent components. In this case, the alkyl group has 2 to 4 carbon atoms.

Of the above-mentioned constituents, those containing one or more compounds selected from the group consisting of naphthalene compound, bifuunyl compound and para-substituted benzene compound as essential constituents are more preferable examples. Of the p-substituted benzene compounds, P-hydroxybenzoic acid, methylhydroquinone and 1-phenylethylhydroquinone are particularly preferred examples.

Specific examples of the compound having an ester-forming functional group as a constituent component and the present invention A specific example of a polymer which is preferably used and forms an anisotropic molten phase is described in JP-B-63-36633.

Liquid crystalline polymers suitable for use in the present invention generally have a weight average molecular weight of about 2,000 to 200,000, preferably about 10,000 to 50,000, and particularly preferably about 20,000 to 25,000. On the other hand, suitable liquid crystalline polyesteramides generally have a weight average molecular weight of about 5,000-50,000, preferably about 10,000-30,000, for example about 15,000-17,000. The determination of the molecular weight can be carried out by gel permeation chromatography and other standard measuring methods which do not involve the formation of a polyester solution, for example, by quantifying the terminal groups by infrared spectroscopy for compression molded films. Alternatively, the molecular weight can be measured using a light scattering method in a pentafluorophenol solution. The aromatic polyesters and polyesteramides described above also exhibit a logarithmic viscosity (IV) of at least about 2.0 dlZg, for example, about 2.0-1.0 dl / g, when dissolved in pentafluorophenol at 0.1% by weight at 60 ° C. Generally shown.

In addition, the resin composition used in the present invention may contain various fibrous, powdery, or plate-like (C) inorganic fillers according to the intended use.

Examples of the fibrous filler include glass fiber, asbestos fiber, carbon fiber, silica fiber, silica / alumina fiber, zirconium fiber, silicon nitride fiber, boron fiber, potassium titanate fiber, stainless steel, anoremium, titanium, copper, and brass. And inorganic fibrous substances such as fibrous materials of metals.

On the other hand, the particulate fillers include carbon black, graphite, silica, quartz powder, glass beads, milled glass fiber, glass balloon, glass powder, calcium silicate, aluminum silicate, kaolin, tanolek, clay, diatomaceous earth, and wollastonite. Metal oxides such as silicates, iron oxides, titanium oxides, zinc oxides, and aluminas; metal carbonates such as calcium carbonate and magnesium carbonate; metal sulfates such as calcium sulfate and barium sulfate; and other silicon carbide and nitrides Boron, silicon nitride, various gold Genus powder.

Examples of the plate-like filler include my strength, glass flakes, and various metal foils.

These inorganic fillers can be used alone or in combination of two or more.

These fillers may be surface-treated using a known surface treatment agent depending on desired physical properties. Examples of the treating agent include functional compounds such as epoxy compounds, isocyanate compounds, titanate compounds, and silane compounds. Preferably, it is treated with a compound other than an amino compound such as an epoxy compound or a polyamide compound.

The amount of the inorganic filler (C) to be added is 1 to 300 parts by weight based on 100 parts by weight of the liquid crystalline polymer composed of the components (A) and (B).

Further, the liquid crystalline polymer composition used in the molded article of the present invention may be one in which another thermoplastic resin is supplementarily added to the extent that the intended purpose is not impaired within the scope of the present invention. .

Although the thermoplastic resin used in this case is not particularly limited, examples thereof include aromatic polyesters such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, and polybutylene naphthalate; polyolefins such as polyethylene and polypropylene; Polyacetal (homo or copolyester), polystyrene, styrene-butadiene copolymer, acrylonitrile-butadiene-styrene copolymer, styrene-butadiene-acrylic acid (or ester thereof) copolymer, acrylonitrile-styrene copolymer, poly Polyvinyl chloride, Polyamide, Polyphenylene oxide, Polyphenylene sulfide, Polysulfone, Polyethersulfone, Polyketone, Polyetherketone, Polyimide, Polyamide Terimid, Polybenzimidazole, Polybutadiene, Butyl rubber, Silicone resin, Fluorine resin, Olefin-based thermoplastic elastomer, Styrene-based thermoplastic elastomer Core-shell multi-layer graft copolymer consisting mainly of elastomers, urethane-based thermoplastic elastomers, polyester-based thermoplastic elastomers, polyamide-based thermoplastic elastomers, polyether-based thermoplastic elastomers, and polyacrylates And their modified forms. These thermoplastic resins can be used as a mixture of two or more kinds.

Further, the composition constituting the molded article of the present invention includes known substances generally added to thermoplastic resins and thermosetting resins, that is, stabilizers such as antioxidants and ultraviolet absorbers, antistatic agents, Flame retardants, coloring agents such as dyes and pigments, lubricants, and the like can also be appropriately added according to required performance.

The resin composition of the present invention can be prepared by equipment and methods generally used for preparing a synthetic resin composition. That is, necessary components are mixed, kneaded using a single-screw or twin-screw extruder, and extruded into a molding pellet, and a part of the necessary components is mixed and molded as a master batch. In order to improve the dispersion and mixing of the components, any or all of the liquid crystalline polymer may be pulverized, mixed, and melt-extruded. Further, in the melt extrusion step, a method of adding fibers and the like while the resin component is being melted is a method in which the fibrous filler is less damaged and the effects of the present invention are sufficiently exhibited.

As a method of obtaining a molded article using the material pellets thus obtained, molding can be performed by using a generally known thermoplastic resin molding method such as injection molding, extrusion molding, vacuum molding, compression molding, or the like. However, injection molding is most preferred.

According to the present invention, in molding a liquid crystalline polymer, a molded product having excellent heat resistance and excellent heat stability without generating a prister during high-temperature heat treatment in a wide range of molding conditions can be obtained. Example Hereinafter, the present invention will be described specifically with reference to Examples, but the present invention is not limited thereto. The evaluation method is as follows.

(Blister temperature measurement)

—Thirty 0.5-mm thick box-shaped products molded under constant conditions are immersed in silicone oil at a specified temperature, washed with a solvent, air-dried, and visually inspected for blisters on the surface. Examined. The blister temperature was the lowest temperature at which the number of blisters out of 30 molded products was zero.

(Melt viscosity)

The material pelletized by the twin-screw extruder was measured for melt viscosity at a shear rate of 216 sec- ¹ using a capillarograph (Toyo Seiki Capillograph 1B).

(Heat resistance stability)

For the material pelletized with the twin-screw extruder, a test sample (type IV; thickness 1 mm) conforming to the method of ASTM D638 was molded using an inline injection molding machine, and the initial tensile strength was calculated as follows. , And another test piece was placed in a gear-oven oven set at 200 ° C, heat-treated under hot air circulation, and the tensile strength and tensile elongation after 1000 hours of treatment were measured.

Examples 1 to 6

The liquid crystalline polymers A, B, C, and D described below and each of the components shown in Table 1 were mixed and pelletized with a normal extruder, and then molded into a 0.5 mm thick box-shaped molded product with an injection molding machine. And evaluated. Table 1 shows the results.

Examples 7 to 8

Evaluation was performed in the same manner as in Examples 1 to 6, except that a liquid crystal polymer A described later and each component shown in Table 2 were mixed. Table 2 shows the results.

Comparative Examples 1-4

As shown in Table 3, the same procedures as in Examples 3 to 6 were carried out except that the first phosphate was not blended. And evaluated. Table 3 shows the results.

Comparative Examples 5 to 7

Evaluation was performed in the same manner as in Examples 1 to 8, except that the liquid crystal polymer A described later and each component shown in Table 4 were mixed. Table 4 shows the results.

Comparative Examples 8 to 11

Evaluation was performed in the same manner as in Examples 1 to 8, except that the liquid crystal polymer A described below and each component shown in Table 5 were mixed. Table 5 shows the results.

The liquid crystalline polymer used in the examples has the following structural units. / _Λ -c-

A: -0 OVC0- "〇Τ o

〇 = 70/30

ίί

0C- <O -C0- / -0- <O> -N- = 60/6/12/17/5

c: -ο- (ρ) -ω-/ —. ”〇1〇“ ^∞ — / -oc- (0 -co-

= 79/20/1

(Normal molar ratio) Table 1 Example 1 Male Example 2 Example 3 Example 4 Jongle 5 Example 6

(Α) Liquid crystalline polyester Α (armpit area) 100 100 100

Liquid crystalline polyesterylamide B (fi content) 100

Liquid crystalline Holistic Al C (parts by weight) 100

Pair

Liquid crystalline polyesterile D (S content) 100 composition

(B) 1st Calcium Phosphate (Halo) 0.01 0.1 0.5 0.1 0.1 0.1

(C) Glass fiber ((A) + (B) 100 parts by weight

45 45 45 45 45 45

Melt viscosity (Pa.S) 66 58 28 50 53 52 Dwell time during molding (minutes) 7 21 7 21 7 21 7 21 7 21 7 21 Blister 'O 250 250 250 250 250 250 280 280 270 260 280 280 Rating

Tension bow Riken (MPa) 200 201 198 163 155 150 valency Tension bow boat 200 ° CX 1000hr (MPa) 184 185 183 150 143 138 Draw bow Si Sekiri Riken (%) 2.2 2.2 2.1 2.5 2.6 2.7 Draw bow S { Degree 20θΤ: Χ 10001ιτ () 2.0 2.0 2.0 2.3 2.4 2.5

Table 2 Example 7 Example 8

(A) Liquid crystalline polyester A (parts by weight) 100 100

(B) Lead metaborate (parts by weight) 0.1

Pair

Barium borate (parts by weight) 0.1

(C) Glass fiber ((A) + (B) 100 parts by weight

45 45 Straight part)

Swelling (Pa · S) 62 45 Dwell time during molding (min) 7 21 7 21 Blister temperature (° C) 250 240 250 240 Rating

Tensile strength Before heat treatment (MPa) 200 201 value Tensile strength 200 ° CX 1000hr (MPa) 180 181 Tensile elongation Before heat treatment (%) 2.1 2.2 Tensile elongation 200 ° CX 1000hr (%) 1.9 2.0

Table 3

Table 4 Comparative Example 5 Comparative Example 6 Comparative Example 7

(A) Liquid crystalline polyester A (parts by weight) 100 100 100

(B), calcium metaphosphate (parts by weight) 0.1

Pair

Calcium phosphate 2 (parts by weight) 0.1 Synthesis Calcium phosphate 3 (parts by weight) 0.1

(C) Glass fiber ((A) + (B) '100 parts by weight

45 45 45 Straight part)

Solution rai viscosity (Pa.S) 66 68 78 Dwell time during molding (min) 7 21 7 21 7 21 Blister temperature (° C) 200 130 190 110 180 110

Tensile strength Before heat treatment (MPa) 201 200 199 value Tensile strength 200 ° CX 1000hr (MPa) 161 160 159 Tensile elongation Before heat treatment (%) 2.1 2.2 2.2 Tensile elongation 200 ° CX 1000hr (%) 1.7 1.7 1.6

Table 5

Claims

The scope of the claims

1. Liquid crystallinity comprising (A) 100 parts by weight of a liquid crystalline polymer and (B) 0.001 to 10 parts by weight of at least one compound selected from the group consisting of primary phosphates, pyrophosphates and borates. A molded product with improved high-temperature heat treatment properties obtained by melt-processing a polymer composition.

2. The molded article according to claim 1, wherein the component (B) is a primary phosphate.

3. The molded article according to claim 1, wherein the amount of the component (B) is 0.0 to 5 parts by weight based on 100 parts by weight of the component (A).

4. The molded article according to claim 1, further comprising (C) 1 to 300 parts by weight of an inorganic filler based on 100 parts by weight of the liquid crystalline polymer composition. '