JPS63139715A - Copolymerized polyester injection molded form - Google Patents

Abstract

PURPOSE:To obtain a high polymerization degree polymer only by melting and polymerization, and to manufacture the title moldable injection molded form having excellent optical anisotropy, heat resistance, rigidity and shock resistance by a normal molding machine by injection-molding copolymerized polyester consisting of a specific structural unit. CONSTITUTION:[(I)+(II)] in the structural unit formulae (I)-(III) of copolymerized polyester occupy 77-95mol% of the whole, and the mol ratio of (I)+(II) extends over 75/25-95/5. These condensation polymerization reactions are accelerated even in a noncatalytic manner, but it is preferable that a metallic compound such as stannous acetate, tetrabytultitanate, sodium acetate and potassium acetate, antimony trioxide, metallic magnesium, etc. is often added. Said copolymerized polyester is injection-molded. The thermal deformation temperature (load 18.6kg/cm<2>) of 150 deg.C or higher of an injection molded form is required.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention provides a polymer with a high degree of polymerization obtained only by melt polymerization, and which has optical anisotropy, heat resistance, rigidity, and can be molded with a normal molding machine.
Endurance 8! This invention relates to a copolymerized polyester injection molded product with excellent mechanical properties such as impact resistance.

<Conventional technology> In recent years, the demand for higher performance plastics has been increasing, and many polymers with various new performances have been developed.Among them, optically anisotropic liquid crystal polymers have excellent mechanical properties. (Japanese Unexamined Patent Publication No. 51-83)
No. 95, JP-A-49-72393).

<Problems to be Solved by the Invention> As the above-mentioned liquid crystal polymer, for example, a liquid crystal polymer prepared by copolymerizing polyethylene terephthalate with p-hydroxybenzoic acid is known (Japanese Unexamined Patent Publication No. 49-72393). Injection molded products made of this polymer have drawbacks such as insufficient heat resistance and poor mechanical properties, and it has been found that injection molded products satisfying both properties cannot be obtained from this polymer. Furthermore, it has been found that in order to improve heat resistance, the amount of p-hydroxybenzoic acid must be 80 mol % or more, but in this case solidification occurs during polymerization, and it has been found that in-phase polymerization is necessary.

On the other hand, as a means to improve the fluidity of such a polymer, improve its melt moldability, and further improve its mechanical properties, for example, as described in JP-A-51-8395, A method has been proposed in which polyethylene terephthalate is copolymerized with p-acylhydroxybenzoic acid, dicarboxylic acid, and aromatic diol, but although the mechanical properties of the injection molded products obtained by this method are improved, the heat resistance is insufficient. On the other hand, the special public
As described in Publication No. 7870, an injection molded product of a wholly aromatic polyester made by copolymerizing ρ-hydroxybenzoic acid with 4,4-dihydroxybiphthalic acid and terephthalic acid has good heat resistance. It was found that since the softening temperature was 400°C or higher, melt polymerization was difficult and the fiI& properties were not fully satisfactory.

Therefore, the object of the present invention is to obtain a copolymerized polyester injection molded product that can be molded using a common injection molding machine and has excellent AM properties and heat resistance.

Means for Solving the Problems> The present inventors have conducted extensive studies to achieve the above objects, and as a result, have arrived at the present invention.

That is, the present invention consists of the following structural units (I) to (1), and the top structural units [(I)+(II)] are 77 to 77 of the total.
95 mol%, structural unit (I[) is 23 to 5 mol% of the total
and the molar ratio of structural units (T)/(It) is 75/
25-9515 copolyester is injection molded, and the heat distortion temperature (load 18.6 kt/J) is 150°C.
This is a copolymerized polyester injection molded product.

+0-CH2CH2-02C-R3-Co)-...
(I represents one or more groups selected from - Structural unit of polyester produced from hydroxybenzoic acid, structural unit i) is 4
．． 4--dihydroxybiphenyl, hydroquinone, 2
．． 6-Sihydroxynaphthalene, 7-butylhydroquinone, 3.3-.

Aromatic diol selected from 5.5′-tetramethyl-4,4′-dihydroxybiphenyl and phenylhydroquinone and terephthalic acid, 4.4′-diphenyldicarboxylic acid, 2,6-naphthalene dicarboxylic acid, 1.2-
bis(phenoxy)ethane-4,4-monodicarboxylic acid,
1.2-bis(2-chlorophenoxy)ethane-4,4
2 shows the #I unit of a polyester produced from an aromatic carboxylic acid selected from dicarboxylic acids.

In addition, the above structural unit (III) is terephthalic acid, 4゜4
-1-diphenyldicarboxylic acid, 2,6-naphthalene dicarboxylic acid, 1,2-bis(phenoxy)ethane-4,4
-1-dicarboxylic acid, 1,2-bis(2-chlorophenoxy)ethane-4,4'-dicarboxylic acid, and an aromatic dicarboxylic acid selected from ethylene glycol. Among these, for R1, the structural units [(I)+(II)] of the above structural units (I) to (III>) account for 77 to 95 mol% of the total, preferably 77 to 87 mol%. be.

Further, the structural unit (III) accounts for 23 to 5 mol% of the total, preferably 23 to 13 mol%. Structural unit [(I
)+(ff)] is more than 95 mol% of the total, the melt fluidity decreases and solidification occurs during polymerization, and if it is less than 77 mol%, the heat resistance is poor, which is undesirable.
) + (n) molar ratio is 75/25 to 9515,
Preferably it is 78/22 to 92/8. If it is less than 75/25 or greater than 9515, the heat resistance or fluidity will be poor, making it impossible to achieve the object of the present invention.

Typical copolyester used in the present invention! ! ! Examples of manufacturing methods include the following.

(1) Acylated products of hydroxybenzoic acids such as p-acetoxybenzoic acid, diacylated products of aromatic dihydroxy compounds such as 4.4-monodiacetoxybiphenyl, aromatic dicarboxylic acids such as terephthalic acid, and ethylene glycols such as polyethylene terephthalate. and a polyester from an aromatic dicarboxylic acid by deacetic acid polymerization.

(2) From aromatic dihydroxy compounds such as p-hydroxybenzoic acid and 4.4-monodihydroxybiphenyl, aromatic dicarboxylic acids such as acetic anhydride and terephthalic acid, and ethylene glycol and aromatic dicarboxylic acids such as polyethylene terephthalate. A method for producing polyester by deacetic acid polymerization.

Although these polycondensation reactions proceed without a catalyst, it is sometimes preferable to add metal compounds such as stannous acetate, tetrabutyl titanate, sodium and potassium acetate, antimony trioxide, and metallic magnesium.

Further, the melt viscosity of the copolymerized polyester used in the present invention is 1
0 to 15,000 boise is preferred, especially 20 to 5.0
00 voids is more preferred.

Note that this melt viscosity is a value measured using a Koka type flow tester under conditions of (liquid crystal starting temperature + 40° C.) and a slip rate of 1.000 (1/sec).

On the other hand, the logarithmic viscosity of this copolyester is 0°1 r
/ d j The value measured in pentafluorophenol at 4 degrees and 60° C. is preferably 065 to 5 dj/g, particularly preferably 1.0 to 3.0 dj/g.

In addition, when polycondensing the copolymerized polyester used in the present invention, in addition to the components constituting the structural units (I) to (III), isophthalic acid, 3.3°-diphenyldicarboxylic acid, 2.2-monodiphenyl Aromatic dicarboxylic acids such as dicarboxylic acids, adipic acid, azelaic acid, sebacic acid,
Aliphatic dicarboxylic acids such as dodecanedioic acid, alicyclic dicarboxylic acids such as hexadroterephthalic acid, chlorohydroquinone, methylhydroquinone, 4,4-dihydroxydiphenylsulfone, 4,4-dihydroxydiphenylpropane, Aromatic diols such as 4,4゛-dihydroxydiphenyl sulfide, 4,4°-dihydroxybenzophenone, 4.4-monodihydroxydiphenyl ether, 1.4=butanediol, 1.6-hexanediol, neopentyl glycol, 1, For the purpose of the present invention, aliphatic and cycloaliphatic diols such as 4-cyclohexanediol and 1,4-cyclohexane dimetatool, and aromatic hydroxycarboxylic acids such as m-hydroxybenzoic acid and 2,6-hydroxynaphthoic acid are used. It is possible to further copolymerize in a small proportion without causing any damage.

The copolymerized polyester injection molded product of the present invention is made of the copolymerized polyester detailed above, and the cylinder temperature is higher than or equal to the liquid crystal start temperature and 330°C or lower, preferably (liquid crystal start temperature +
10℃) or more and 320℃ or less, mold temperature is 10℃ or more and 15
It is obtained by injection molding into a three-dimensional molded article or the like at a temperature of 0°C or lower, preferably 30°C or higher and 120°C or lower.

The copolyester injection molded product of the present invention includes reinforcing materials such as glass fiber, carbon fiber, and asbestos, fillers, nucleating agents, pigments, antioxidants, stabilizers, plasticizers, lubricants, mold release agents, and combustion agents. Additives and other thermoplastics can be added to impart desired properties.

The heat distortion temperature of the injection molded product of the present invention (load: 18°6 kt)
/cJ) is a value measured according to ASTM D648, which must be 150°C or higher, and 180°C or higher.
℃ or higher is preferable.

In addition, the injection molded product obtained in this way can have its strength increased by heat treatment, and may also have its elastic modulus increased.

This heat treatment can be carried out by heat treating the injection molded article in an inert atmosphere (eg nitrogen, argon, helium or water vapor) or in an oxygen-containing atmosphere (eg air) at a temperature below the melting point of the polymer. This heat treatment may or may not be under tension, and can be carried out for several tens of minutes to several days.

<Example> The present invention will be further explained below with reference to Examples.

Example 1 60.8 p-acetoxybenzoic acid (I) in a test tube for polymerization
0g (33,75X10-2 mol), 4゜4゛-diacetoxybiphenyl (II>12.16t (4,5X1
0-2 mol), terephthalic acid 7°47+r (4,5X1
12.97 g (6,75X1
0-2 mol) to [(I)+(II)]/[(1)+(I
The mixture was charged so that I)+(II[)] was 85 mol% and the molar ratio of (I)/(II) was 88/12, and acetic acid depolymerization was carried out under the following conditions.

First, in a nitrogen gas atmosphere at 250-300°C and 0°2
The pressure was reduced to m Hg, and the reaction was further carried out for 3.25 hours to complete the polycondensation, whereupon acetic acid as a theoretical group was distilled out and a beige polymer was obtained. Further, 5 batches of polymerization were performed under the same conditions, the polymer was recovered, and the polymer was pulverized using a pulverizer manufactured by Seisaku Co., Ltd.

The theoretical structural formula of this polymer is as follows, and the elemental analysis results of the polyester showed good agreement with the theoretical values.

j/m/n=75/10/15 Also, place this polyester on the sample stage of a polarizing microscope,
As a result of confirming the optical anisotropy by raising the temperature, the liquid crystal initiation temperature was 264° C., indicating good optical anisotropy.

This polyester was subjected to a Sumitomo Nestal injection molding machine Promat 40/25 (manufactured by Sumitomo Heavy Industries Co., Ltd.),
1 under the conditions of cylinder temperature 300℃ and mold temperature 30℃
/8" thick x 1/2" 1% F, x 5" long test piece and 1/8" thick x 2 1/2" long mold notch and impact test piece were created. This test piece was Using Tensilon UTM-Zoo manufactured by Baldwin Co., Ltd., the bending elastic modulus was measured under the conditions of a strain distance of 1111/min and a span distance of 50 mm, and it was found to be 10.2 GPa.The Izotsu impact value was 36 b/am/am. showed a high value.

In addition, when the heat distortion temperature of a 1/8" thick test piece was measured using Toyo Seiki's heat distortion temperature VTM, it was 206"C (1
8.60 kg/cd).

The logarithmic viscosity of this polymer was 1.34 dj/g, and the melt viscosity was 310 voices at 304° C. and a sliding speed of 1.000 (1/sec), indicating extremely good fluidity.

Example 2 60°80t of p-acetoxybenzoic acid (
33,75 x 10 ”mol) (1), 12.16 g (4,5x
lO-2 mol), 4,4-diphenyldicarboxylic acid 1
18.31 g of polyethylene-4゜4゛-diphenyldicarboxylate/polyethylene terephthalate copolymer (molar ratio 6/4) (II) with 0.89sr (4,5X10-2 mol) and an intrinsic viscosity of 0.7 ( 6,75xlO
-2 mol) to [(I)+(II)]/[(I)+(II)
)+(1)] was 85 mol% and the molar ratio of (I)/(II) was 88/12, and polycondensation was carried out under the same conditions as in Example 1 to obtain a polyester with a liquid crystal initiation temperature of 258°C. Ta.

The theoretical structural formula of this polymer is as follows, and the elemental analysis results of the polyester showed good agreement with the theoretical values.

J/m/n=75/10/15 This polyester was injection molded under the same conditions as in Example 1, and the #R mechanical properties and thermal properties of the obtained molded product were measured. As a result, the bending modulus is 10.5G at 178″ thickness.
Pa and Izotsu impact value (mold notch) is also 38
．． It showed a high value of 3kg・C1l/011. In addition, the heat distortion temperature of the 1/8” thick test piece is 200℃ (18,5
6+qr/cj).

The logarithmic viscosity of this polymer was 1.48 dj/g, and the melt viscosity was 240 voids at 308° C. and a sliding speed of 1,000 (1/sec), indicating excellent fluidity.

Comparative Example 1 7υ of p-acetoxyammonium and 24 fragric acid (I) in a test tube for polymerization
．． 32g (13,5x, 10-2 mol), hydroquinone diacetate (II) 26.19r (13,5x
10”mol), 22.43g terephthalic acid<13.
5xlO-2 mol), polyethylene terephthalate (I
N) 34.59t (18,0x10-2 mol) (Structural unit [(I) + (II)] is 60 mol% of the whole,
)/(n) molar ratio was 50150) and polycondensation was carried out according to the conditions of Example 1 to obtain a polyester having a liquid crystal initiation temperature of 251°C.

Polyester was injection molded under the conditions of Example 1, and the mechanical properties and thermal properties of the resulting molded product were measured. As a result, the bending elastic modulus was 7°0 GPa at 1/8" thickness, and the isot impact strength (mold notch) was 25,5
kg-CI+/3.1/8” thickness heat distortion temperature is 130℃
(18.56 kg/cd), and the heat resistance was extremely poorer than that of the polyester of the present invention.

Examples 3 to 11, Comparative Examples 2 to 4 p-acetoxybenzoic acid (I>, 4.4
-monodiacetoxybiphenyl (II-1), hydroquinone diacetate (ff-2>, 2.6-diacedoxynaphthalene (n-3>), t-butylhydroquinone diacetate (II-4), phenylhydroquinone diacetate (n-5), 3゜3-.5.5-tetramethyl-4,4-monodiacetoxybiphenyl (n-6), terephthalic acid (IV-1), 4.4-diphenyldicarboxylic acid ( IV-2), 1,2-bis(phenoxy)ethane-4,4-dicarboxylic acid (IV-3), 1, 2-
Bis(2-chlorophenoxy)ethane-4,4-monodicarboxylic acid (IV-4>, 2,6-naphthalene dicarboxylic acid (IV-5) (of these, (IF-1) to (II-6))
Components (IV-1) to (IV-5> are charged with the same number of moles) and polyethylene terephthalate (■) with an intrinsic viscosity of 0°60 are charged into a polymerization test tube,
Polycondensation reaction and injection molding were carried out under the same conditions as in Example 1, and the liquid crystal initiation temperature, melt viscosity, mechanical properties, and thermal properties were measured. As is clear from Table 1, the polymer of the present invention has good fluidity, and the flexural modulus of injection molded products is
The Izot impact strength is also good, and the heat distortion temperature is 19
The temperature was 0°C or higher, which was extremely excellent. On the other hand, the polymer of Comparative Example 2 has almost the same fluidity and elastic modulus as the polymer of the present invention, but the heat distortion temperature is 58°C, which is significantly inferior in heat resistance. It was found that the properties were poor, the R mechanical properties were greatly inferior, and the heat resistance was also inferior to the polyester of the present invention.

On the other hand, the polymer of Comparative Example 4 had a melting point of 450°C or higher and could not be injection molded.

Examples 12-14 60.8 p-acetoxybenzoic acid (I) in a test tube for polymerization
0g (33,75X10-2 mol), 12.16g (4,5X11
0-2 mol), terephthalic acid 7°49g (4,5xl
O-2 mol) and a logarithmic viscosity of 0.68 dJ/g measured in orthochlorophenol at 25°C at a 0.5% concentration.
of polyethylene-2,6-naphthalene dicarboxylate (Example 12) or with a logarithmic viscosity of 0.72 dJ/,
Polyethylene-1,2-bis(phenoxy)ethane-4
,,4°-dicarboxylate (Example 13) or polyethylene-1,2-bis(2-chlorophenoxy)ethane-4,4-dicarboxylate with a logarithmic viscosity of 0.866j/r (Example 14) ) respectively 6.75xlO
-2 molar amount The liquid crystal initiation temperature and melt viscosity of the polymer obtained by charging and polymerizing in the same manner as in Example 1 were measured. Then, injection molding evaluation was performed in the same manner as in Example 1.

These results are shown in Table 2.

Table 2 shows that these polyesters have good fluidity and excellent mechanical properties and heat resistance.

Table 2 <Effects of the Invention> The copolymerized polyester injection molded product of the present invention exhibits good heat resistance and mechanical properties, so it can be used for divine purposes such as metal substitute plastic molded products.

Claims (1)

[Claims] Consisting of the following structural units (I) to (III), the structural unit [(
I)+(II)] is 77 to 95 mol% of the total, the structural unit (III) is 23 to 5 mol% of the total, and the structural unit (I
)/(II) molar ratio of 75/25 to 95/5.
A copolyester injection molded product having a temperature of 8.6 kg/cm^2) of 150°C or higher. ▲There are mathematical formulas, chemical formulas, tables, etc.▼...(I) -(O-R_1-O_2C-R_2-CO)-(II) -(O-CH_2CH_2-O_2C-R_3-CO)
−…(III) (However, R_1 in the formula is ▲There are mathematical formulas, chemical formulas, tables, etc.▼, ▲There are mathematical formulas, chemical formulas, tables, etc.▼, ▲There are mathematical formulas, chemical formulas, tables, etc.▼, ▲Mathematical formulas, chemical formulas, There are tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ Mathematical formulas,
There are chemical formulas, tables, etc. ▼ One or more groups selected from R_2, R_3 are ▲ Numerical formulas, chemical formulas, tables, etc. ▼,
▲There are mathematical formulas, chemical formulas, tables, etc.▼, ▲Mathematical formulas, chemical formulas,
There are tables, etc. ▼, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼
represents one or more groups selected from R_2 and R_3 may be the same. However, in the formula, X represents a hydrogen atom or a chlorine atom. )