JP2003096180A - Straight-chain polycarbonate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a straight-chain polycarbonate, which is improved in fluidity, gives no deposits to molds when it is injection-molded, and also gives good appearance to the molded articles. SOLUTION: The straight-chain polycarbonate is produced by using a long- chain monoalkylphenol having in average a 19-35C alkyl group as an end- terminator, the amount of the unreacted long-chain monoalkylphenol being 300 ppm or less, and has a viscosity-average molecular weight of 13,500-30,000.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linear polycarbonate, and more specifically, it has improved flowability, no deposits are seen on the mold when injection molding, and the appearance of the molded product is good. It relates to a linear polycarbonate.

[0002]

2. Description of the Related Art Polycarbonate resin has excellent mechanical properties (especially impact resistance), electrical properties, transparency, etc.
It is widely used in various fields such as A equipment, electric and electronic equipment fields, and construction fields.

In recent years, it has become necessary to further improve the fluidity in order to meet the demand for thinner and larger molded products and improved molding cycle. It is known to use long-chain alkylphenols as endcappers to improve their flowability. For example, Japanese Patent Publication No. 52-50078 describes that an alkylphenol having an alkyl group having 8 to 20 carbon atoms, a carboxylic acid or an acid halide is used as a terminal terminating agent. However, the examples only describe acid chlorides having an alkyl group having 9 to 17 carbon atoms, and when the carbon number exceeds 20, the system becomes emulsified when the polymer solution is washed with water, and the washing becomes difficult. There is a description that the heat distortion temperature of the obtained polycarbonate resin is remarkably lowered. In addition, Japanese Patent Fair 7-2
In the claims of Japanese Patent No. 5871, there is a description that an alkylphenol having an alkyl group having 8 to 30 carbon atoms is used as a terminal stopper. However, the examples only disclose alkylphenols having an alkyl group with 18 carbon atoms.

On the other hand, when a polycarbonate obtained by using a long-chain alkylphenol as a terminal stopper is injection-molded, deposits are found on the mold and the molded product tends to have surface unevenness.

[0005]

SUMMARY OF THE INVENTION The present invention has been made under such circumstances, and has improved fluidity, and when injection molding is performed, deposits are not seen on the mold, and the appearance of the molded product is improved. Also provides a good linear polycarbonate.

[0006]

As a result of intensive studies to achieve the above-mentioned object, the present inventor has used a long-chain monoalkylphenol having a specific carbon number as a terminal stopper and obtained a polycarbonate. It has been found that the object of the present invention can be met by adjusting the amount of unreacted long-chain monoalkylphenol in the composition. The present invention has been completed based on such findings.

That is, the gist of the present invention is as follows. 1. A long-chain monoalkylphenol having an alkyl group having an average carbon number of 19 to 35, which is produced as an end-stopper, and has an unreacted long-chain monoalkylphenol amount of 300 ppm or less, and a viscosity average molecular weight of 13,500 to
30,000 linear polycarbonate. 2. The linear polycarbonate as described in 1 above, wherein the alkyl group of the long-chain monoalkylphenol has an average carbon number of 21 to 25.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is described in detail below. Examples of the linear polycarbonate of the present invention include various ones.

[0009]

[Chemical 1]

A polymer having a repeating unit represented by the following formula is preferred. In the general formula (I), X ¹ and X ² each represent a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms, and specific examples include a methyl group,
Ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, n-amyl group, isoamyl group, n-hexyl group, isohexyl group,
Examples thereof include cyclopentyl group and cyclohexyl group. X ¹ and X ² may be the same or different. a and b are X ¹ and X, respectively
^It shows the number of substitutions of ² and is an integer of 0-4. When plural X ^1, a plurality of X ¹ may be the same as or different from each other, if X ² is plural, X ² may be the same with or different from each other.

Y is a single bond, an alkylene group having 1 to 8 carbon atoms (for example, a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, a hexylene group), an alkylidene group having 2 to 8 carbon atoms (for example, an ethylidene group). , Isopropylidene group, etc.), C5-C15 cycloalkylene group (for example, cyclopentylene group, cyclohexylene group, etc.), C5-C15 cycloalkylidene group (for example, cyclopentylidene group, cyclohexylidene group, etc.) ), - S -, - SO -, - SO 2 -, - O -, - CO
-Bond or formula (II-1) or formula (II-2)

[0012]

[Chemical 2]

The bond represented by Here, the linear polycarbonate refers to one produced without using a branching agent. The polymer is usually represented by the general formula (III)

[0014]

[Chemical 3]

(Wherein X ¹ , X ² , a, b and Y are
Same as above. ) And a dihydric phenol represented by), and a carbonate precursor such as phosgene or a carbonate compound can be produced. That is, for example, in a solvent such as methylene chloride, in the presence of a known acid acceptor and a molecular weight modifier, by the reaction of a dihydric phenol with a carbonate precursor such as phosgene, or in the presence or absence of a solvent, two It can be produced by a transesterification reaction of a polyhydric phenol with a carbonate precursor such as a carbonate compound.

As the dihydric phenol represented by the general formula (III), various ones can be mentioned. Especially 2,
2-bis (4-hydroxyphenyl) propane [common name,
Bisphenol A] is preferred. Examples of dihydric phenols other than bisphenol A include bis (4) such as bis (4-hydroxyphenyl) methane; 1,1-bis (4-hydroxyphenyl) ethane; 1,2-bis (4-hydroxyphenyl) ethane. -Hydroxyphenyl) alkane, 1,1-bis (4-hydroxyphenyl) cyclohexane; bis (4-hydroxyphenyl) cycloalkane such as 1,1-bis (4-hydroxyphenyl) cyclodecane, 4,4'-dihydroxydiphenyl , Bis (4-hydroxyphenyl) oxide, bis (4-hydroxyphenyl) sulfide, bis (4-hydroxyphenyl) sulfone, bis (4-hydroxyphenyl) sulfoxide, bis (4-hydroxyphenyl) ether, bis (4- (Hydroxyphenyl) ketone, etc. be able to. In addition to these, examples of the dihydric phenol include hydroquinone. These dihydric phenols may be used alone or in combination of two or more.

Examples of the carbonic acid ester include diaryl carbonate such as diphenyl carbonate, dialkyl carbonate such as dimethyl carbonate and diethyl carbonate. In the present invention, when the polycarbonate is produced by reacting the dihydric phenol with the carbonate precursor, the average carbon number of the end-capping agent (also referred to as molecular weight modifier) is 19 to 19.
It is essential to use long-chain monoalkylphenols with 35 alkyl groups. If the average carbon number is less than 19, the improvement in fluidity is insufficient, and if it exceeds 35,
The reactivity is poor and the loss of long-chain monoalkylphenol increases accordingly. Those having an average carbon number of 21 to 35 are preferable, and those having an average carbon number of 21 to 25 are more preferable.

The average carbon number of the alkyl group is the sum of [the product of (the number of carbons of the alkyl group) and (the mole fraction thereof)]. The above long-chain monoalkylphenols may be used alone or in combination of two or more. When two or more kinds are used in combination, the carbon number of the alkyl group is represented by the average carbon number.

Further, the above long-chain monoalkylphenol has isomers, such as ortho-form, meta-form and para-form, but any of them may be used. In addition, the long-chain alkyl group is linear,
It may be branched. The linear polycarbonate of the present invention needs to have a viscosity average molecular weight in the range of 13,500 to 30,000 from the viewpoint of mechanical strength and moldability. The range is preferably 14,000 to 25,000, more preferably 14,500 to 21,000. The viscosity-average molecular weight (Mv) was measured by measuring the viscosity of the methylene chloride solution at 20 ° C. using an Ubbelohde viscometer, and determining the intrinsic viscosity [η] from this [η].
= 1.23 × 10 ⁻⁵ Mv ^0.83 .

The unreacted long-chain monoalkylphenol of the linear polycarbonate of the present invention needs to be 300 ppm or less. The method for reducing the concentration to 300 ppm or less is not particularly limited. For example, in the solution method, precipitation of the polycarbonate generated in the poor solvent may be filtered and separated. If it exceeds 300 ppm, deposits are seen on the mold for injection molding, and the appearance of the molded product is not good, which is not preferable. It is preferably 200 ppm or less, more preferably less than 100 ppm.

The linear polycarbonate of the present invention may optionally contain various additives such as antioxidants, lightness improvers, lubricants (release agents), flame retardants, etc. within the range not impairing the object of the present invention. An anti-drip agent and other inorganic fillers may be appropriately contained. A composition can be prepared by mixing various additives into the polycarbonate of the present invention and kneading. As the compounding and kneading method, the method applied to a usual resin composition can be applied as it is, and a ribbon blender, a Henschel mixer, a Banbury mixer, a drum tumbler, a single-screw or two or more multi-screw extruder, a co-kneader and the like can be used. The method used is preferred. The kneading temperature is not particularly limited, but is usually 240 to 34.
It is preferably selected from the range of 0 ° C.

The resin composition thus obtained can be molded by a usual molding method such as injection molding or compression molding to obtain a molded product.

[0023]

EXAMPLES The present invention will now be described in more detail by way of examples, which should not be construed as limiting the invention thereto. (1) Preparation of long-chain monoalkylphenol [Preparation of long-chain monoalkylphenol (a)] In a reactor equipped with baffles and stirring blades, a mixture of 300 parts by mass of phenol and 1-eicosene, 1-docosene and 1-tetracosene [ Composition ratio (mol%); 53.3: 40.2:
6.5] 105 parts by mass [phenol / olefin = 9 /
1 (molar ratio)] and a highly acidic polystyrene sulfonic acid type cation resin (Amberlyst 15; manufactured by Rohm and Haas Co.) as a catalyst at a charge ratio of 10.5 parts by mass, the reaction raw materials and the catalyst were charged, and the mixture was stirred at 120 ° C. under stirring. The reaction was carried out for 3 hours. After completion of the reaction, the product was purified by distillation under reduced pressure to obtain a long-chain monoalkylphenol (a).
The average carbon number of the alkyl group of the obtained long-chain monoalkylphenol (a) was 21.

[Preparation of long-chain monoalkylphenol (b)] In the preparation of the long-chain monoalkylphenol (a), 110 parts by mass of 1-dococene [phenol / olefin = 9/1 (molar ratio)] was used as the olefin. A long-chain monoalkylphenol (b) was obtained in the same manner except that the amount of the catalyst used was 11 parts by mass. The average carbon number of the alkyl group of the obtained long-chain monoalkylphenol (b) was 22.

(2) Preparation of Polycarbonate Oligomer Bisphenol A was dissolved in a 5.6 mass% sodium hydroxide aqueous solution so that the concentration of bisphenol A was 13.5 mass% to prepare a sodium hydroxide aqueous solution of bisphenol A. did.

Phosgene was continuously fed to a tubular reactor having an inner diameter of 6 mm and a pipe length of 30 m at a flow rate of 41 liter / hr of sodium hydroxide solution of bisphenol A and 15 liter / hr of methylene chloride at a flow rate of 4.0 kg / hr. Supplied. The tubular reactor had a jacket, and cooling water was passed through the jacket to keep the temperature of the reaction solution at 40 ° C. or lower.

The reaction solution discharged from the tubular reactor was continuously introduced into a tank-type reactor with a baffle having an internal volume of 40 liters equipped with a retreating blade, and 2.8 liters of a sodium hydroxide aqueous solution of bisphenol A was further introduced therein. / Hr, 25 mass% sodium hydroxide aqueous solution 0.07 liter / hr, water 17 liter / hr, 1 mass% triethylamine aqueous solution 0.32
The reaction was carried out by adding liter / hr.

The reaction liquid overflowing from the tank reactor was continuously withdrawn and allowed to stand to separate and remove the aqueous phase, and the methylene chloride phase was collected. The concentration of the polycarbonate oligomer thus obtained was 355 g / liter,
The chloroformate group concentration was 0.80 mol / liter.

(3) Production of Polycarbonate [Example 1] 12 liters of the above oligomer solution and 9.3 liters of methylene chloride were placed in a 50 liter tank reactor equipped with baffles, two paddle type stirring blades and a cooling jacket.
352 g of long-chain monoalkylphenol (a) and 5.4 ml of triethylamine were charged, and 226 mg of sodium dithionite was dissolved therein to obtain 6.4% by mass.
1,720 g of an aqueous sodium hydroxide solution was added with stirring, and the reaction was performed for 20 minutes. Then bisphenol A
Aqueous sodium hydroxide solution (580 g of NaOH, 1.98 g of sodium dithionite dissolved in 9.78 liters of water and 992 g of bisphenol A dissolved therein) was added, and the polymerization reaction was continued for 40 minutes while stirring at 300 rpm. Carried out.

Next, after adding 10 liters of methylene chloride for dilution, the mixture was allowed to stand to separate into an organic phase containing polycarbonate and an aqueous phase containing excess bisphenol A and sodium hydroxide. It was extracted and isolated. A methylene chloride solution of the polycarbonate thus obtained was sequentially added to the solution in an amount of 15% by volume of 0.03 mol / liter sodium hydroxide aqueous solution,
It was washed with 0.2N hydrochloric acid and then washed with pure water until the electric conductivity in the aqueous phase after washing was 0.1 μS / m or less.

After washing, the methylene chloride solution of polycarbonate was concentrated to a concentration of 150 to 170 g / liter, 20% by volume of n-hexane was added, and the resulting precipitate was filtered and dried to obtain polycarbonate flakes. It was The viscosity average molecular weight, Q value, and unreacted long-chain monoalkylphenol amount of the flakes were measured in the following manner, and the results are shown in Table 1.

Method for measuring physical properties of polycarbonate flake (a) Viscosity average molecular weight (Mv) The viscosity of a methylene chloride solution at 20 ° C. was measured using an Ubbelohde viscometer, and the intrinsic viscosity [η] was calculated from this, and [η] ] = 1.23 × 10 ⁻⁵ Mv ^0.83 . (B) Q value (flow value) The melt viscosity measured by an elevated flow tester is 280
The amount of molten resin flowing out from a nozzle of 1 mmφ × 10 mmL under a pressure of 15.7 MPa at a temperature of 1 ° C. is expressed in units of cc / sec.
The value "increases. (C) Unreacted long-chain monoalkylphenol amount 2 g of polycarbonate flakes were dissolved in 50 ml of methylene chloride, and 250 ml of acetone was added little by little to precipitate a polymer. This was suction-filtered and then concentrated, and the concentrated liquid was quantified by gas chromatography (GC) after being made up to a constant volume with 20 ml of n-hexane. The measurement conditions are as follows.

GC body: HEWLETT PACKAR
D HP 6890 column: J & W SCIENTIFIC, DB-1
(15 m × 0.53 mmφ × 0.15 μm) Temperature pattern: 40 ° C./minute hold → 40 ° C./minute temperature rise → 1
Hold at 20 ° C / 7 minutes → Temperature rise for 10 minutes / minute → Hold at 330 ° C / 5 minutes Carrier gas: Helium (40 cm ³ / sec, constant flow) Injection: Splitless (2.0 μl) Injection temperature: 350 ° C FID Detector Temperature: 350 ° C

Example 2 Polycarbonate flakes were prepared in the same manner as in Example 1, except that 365 g of long-chain monoalkylphenol (b) was used instead of long-chain monoalkylphenol (a). The viscosity average molecular weight, Q value, and unreacted long-chain monoalkylphenol amount were measured in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 1 A polycarbonate flake was prepared in the same manner as in Example 1, except that 198 g of lauric acid chloride was used instead of the long-chain monoalkylphenol (a). The viscosity average molecular weight and Q value were measured in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 2 Polycarbonate flakes were prepared in the same manner as in Example 1, except that 249 g of palmitic acid chloride was used instead of the long-chain monoalkylphenol (a). Its viscosity average molecular weight, Q
The value was measured as in Example 1. The results are shown in Table 1.

Comparative Example 3 A polycarbonate flake was prepared in the same manner as in Example 1 except that 270 g of stearic acid chloride was used instead of the long chain monoalkylphenol (a). Its viscosity average molecular weight, Q
The value was measured as in Example 1. The results are shown in Table 1.

Comparative Example 4 Polycarbonate flakes were prepared in the same manner as in Example 1, except that 314 g of octadecylphenol was used instead of the long-chain monoalkylphenol (a). Its viscosity average molecular weight, Q
The value was measured as in Example 1. The results are shown in Table 1.

Example 3 Polycarbonate flakes were prepared in the same manner as in Example 1, except that the amount of the long-chain monoalkylphenol (a) added was 292 g. The viscosity average molecular weight, Q value, and unreacted long-chain monoalkylphenol amount were measured in the same manner as in Example 1. The results are shown in Table 1.

Example 4 A polycarbonate flake was prepared in the same manner as in Example 1 except that 303 g of the long-chain monoalkylphenol (b) was used instead of the long-chain monoalkylphenol (a). The viscosity average molecular weight, Q value, and unreacted long-chain monoalkylphenol amount were measured in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 5 Polycarbonate flakes were prepared in the same manner as in Example 1, except that 234 g of dodecyl p-hydroxybenzoate was used instead of the long-chain monoalkylphenol (a). The viscosity average molecular weight and Q value were measured in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 6 Polycarbonate flakes were prepared in the same manner as in Example 1, except that 210 g of palmitic acid chloride was used instead of the long-chain monoalkylphenol (a). Its viscosity average molecular weight, Q
The value was measured as in Example 1. The results are shown in Table 1.

Comparative Example 7 Polycarbonate flakes were prepared in the same manner as in Example 1, except that 262 g of octadecylphenol was used instead of the long-chain monoalkylphenol (a). Its viscosity average molecular weight, Q
The value was measured as in Example 1. The results are shown in Table 1.

Example 5 Polycarbonate flakes were prepared in the same manner as in Example 1, except that the amount of the long-chain monoalkylphenol (a) added was 266 g. The viscosity average molecular weight, Q value, and unreacted long-chain monoalkylphenol amount were measured in the same manner as in Example 1. The results are shown in Table 1.

Example 6 Polycarbonate flakes were prepared in the same manner as in Example 1 except that 276 g of long-chain monoalkylphenol (b) was used instead of the long-chain monoalkylphenol (a). The viscosity average molecular weight, Q value, and unreacted long-chain monoalkylphenol amount were measured in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 8 Polycarbonate flakes were prepared in the same manner as in Example 1, except that 146 g of lauric acid chloride was used instead of the long-chain monoalkylphenol (a). The viscosity average molecular weight and Q value were measured in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 9 Polycarbonate flakes were prepared in the same manner as in Example 1, except that 184 g of palmitic acid chloride was used instead of the long-chain monoalkylphenol (a). Its viscosity average molecular weight, Q
The value was measured as in Example 1. The results are shown in Table 1.

Comparative Example 10 Polycarbonate flakes were prepared in the same manner as in Example 1, except that 199 g of stearic acid chloride was used instead of the long-chain monoalkylphenol (a). Its viscosity average molecular weight,
The Q value was measured as in Example 1. The results are shown in Table 1.

[Comparative Example 11] Polycarbonate flakes were prepared in the same manner as in Example 1, except that n-hexane was added, the mixture was directly concentrated without filtering, and the obtained solid content was dried. The viscosity average molecular weight, Q value, and unreacted long-chain monoalkylphenol amount were measured in the same manner as in Example 1. The results are shown in Table 1.

[Comparative Example 12] Polycarbonate flakes were prepared in the same manner as in Comparative Example 1, except that n-hexane was added, the mixture was directly concentrated without filtering, and the obtained solid content was dried. The viscosity average molecular weight, Q value, and unreacted long-chain monoalkylphenol amount were measured in the same manner as in Example 1. The results are shown in Table 1.

[0051]

[Table 1]

(4) Polycarbonate Injection Molding The polycarbonate flakes obtained in Examples 1 to 6 and Comparative Examples 11 and 12 were treated with Irgafos 168 (manufactured by Ciba Specialty Chemicals) as a phosphorus-based antioxidant.
Was added at 50 ppm and granulated at 270 ° C. to obtain pellets. Cylinder temperature of the obtained pellets was 45 using a 45-ton injection molding machine (IS45PV manufactured by Toshiba Machine Co., Ltd.).
20 ° C, mold temperature; 50 ° C, injection pressure; 7.84 MPa
Injection molding under the conditions of 300 shots of 35 ×
A molded piece having a thickness of 25 mm and a thickness of 3 mm was obtained. Then, the presence or absence of deposits on the mold and the appearance of the molded product were observed.

When the pellets made from the polycarbonate flakes obtained in Examples 1 to 6 were used, there was no deposit on the mold and the appearance of the molded product was good, but Comparative Example 11 When the pellets made from the polycarbonate flakes obtained in No. 12, 12 are used, oily deposits are seen on the mold, and the molded product has uneven surface and a uniform and smooth appearance. did not become.

[0054]

EFFECTS OF THE INVENTION According to the present invention, it is possible to obtain a linear polycarbonate having improved fluidity, no deposits on the mold when injection molding, and a good appearance of the molded product.

Claims (2)

[Claims] 1. A viscosity average molecular weight 1 produced by using a long-chain monoalkylphenol having an alkyl group having an average carbon number of 19 to 35 as an end terminating agent and having an unreacted long-chain monoalkylphenol amount of 300 ppm or less.
3,500-30,000 linear polycarbonate. 2. The linear polycarbonate according to claim 1, wherein the alkyl group of the long-chain monoalkylphenol has an average carbon number of 21 to 25.