JP2001335629A - Production method of aromatic-aliphatic copolymerized polycarbonate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a production method of an aromatic-aliphatic copolymerized polycarbonate having an excellent shock resistance, a high heat resistance, a high Abbe's number and a low photoelastic constant, and which is excellent in color tone. SOLUTION: As a reactor, a stainless steel whose surface touching liquid is electropolished, and which contains a nickel of 8 wt.% or more, a chromium of 16 wt.% of more and an iron of 50 wt.% or more is applied.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a transparent aromatic-aliphatic copolymer polycarbonate having excellent impact strength, high refractive index and Abbe number, low photoelastic constant and excellent hue. The polycarbonate resin can be suitably used for optical materials such as various lenses, prisms, optical disk substrates, and optical fibers.

[0002]

2. Description of the Related Art A polycarbonate obtained by interfacially polymerizing an aromatic dihydroxy compound such as 2,2-bis (4-hydroxyphenyl) propane (hereinafter, referred to as BPA) and phosgene in the presence of an acid binder is: Because of its excellent mechanical properties such as impact resistance, and also excellent heat resistance and transparency, it is used as an optical material for various lenses, prisms, optical disk substrates, and the like. However, polycarbonate using only BPA as the aromatic dihydroxy compound has a large photoelastic constant and relatively low melt fluidity, so that the birefringence of the molded product becomes large, and the refractive index is as high as 1.58. Since the Abbe number is as low as 30, it does not always have sufficient performance to be used for applications such as optical recording materials and optical lenses. Such BPA
For the purpose of solving the drawbacks of polycarbonate, there has been proposed a copolymerized polycarbonate of BPA and tricyclo (5.2.1.0 ^2,6 ) decane dimethanol (hereinafter, referred to as TCDDM) (JP-A ^64-64 ). No. 66234). The aromatic-aliphatic copolymerized polycarbonate has excellent impact resistance and heat resistance, and furthermore, has a small photoelastic constant and a high Abbe number, so that it can be widely used as an optical material. However, the aromatic-aliphatic copolymerized polycarbonate is difficult to produce by a normal phosgene method, and a method known as a transesterification method, that is, an aromatic dihydroxy compound and an aliphatic dihydroxy compound, and diphenyl carbonate and the like It is manufactured by a method in which polycondensation with a carbonic acid diester is carried out by transesterification in a molten state.

As described above, when the aromatic-aliphatic copolymerized polycarbonate is produced by a transesterification reaction, 2
Since polycondensation is carried out while heating to a temperature of from 00 ° C. to 300 ° C., it has been difficult to obtain a product having excellent quality such as deterioration of color due to a long-term heat history at a high temperature. In particular, when a steel reactor is used, deterioration of the color tone is inevitable even when techniques such as reduction of reaction time and reaction temperature are used, and the aromatic-aliphatic polycarbonate is excellent in industrial production. However, it is difficult to use it in a field requiring a high color tone.

[0004]

SUMMARY OF THE INVENTION The present invention aims to solve the problems associated with the prior art as described above, and provides excellent impact resistance, heat resistance, high Abbe number and low photoelastic constant. It is an object of the present invention to provide a method for producing the aromatic-aliphatic polycarbonate having excellent color tone.

[0005]

Means for Solving the Problems The present inventors have conducted intensive studies to solve these problems, and as a result, the following formula (1)
An aromatic dihydroxy compound represented by the following formula (2):
In producing an aromatic-aliphatic copolymerized polycarbonate by melt-polycondensation of TCDDM represented by the following formula and a carbonic acid diester, the surface of the liquid-contacting portion is electropolished as a reaction device, and nickel is contained in an amount of 8% by weight or more. , 16 chrome
By using a stainless steel containing 50% by weight or more and 50% by weight or more of iron, it was found that an aromatic-aliphatic copolymer polycarbonate excellent in color tone could be obtained, and the present invention was reached.

Embedded image (In the above formula (1), X is

Embedded image Wherein R ₃ and R ₄ are a hydrogen atom, a carbon atom of 1
10 to 10 alkyl groups or phenyl groups, and R ₃ and R
₄ may combine to form a ring. R ₁ and R ₂ are a hydrogen atom, an alkyl group having 1 to 10 carbon atoms or halogen, and R ₁ and R ₂ may be the same or different.
Further, m and n represent the number of substituents and are integers of 0 to 4. )

Embedded image

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a method for producing an aromatic-aliphatic copolymer polycarbonate according to the present invention will be specifically described.

[0007] The reactor used in the present invention is made of stainless steel containing at least 8% by weight of nickel, at least 16% by weight of chromium, and at least 50% by weight of iron. , Manganese, silicon,
It may contain elements such as phosphorus, sulfur, and nitrogen. Specific examples of the stainless steel in the present invention include JIS SUS304 (nickel content: 8.0 to 10.5% by weight, chromium content: 18.0 to 20.0% by weight, iron content: 66.35% by weight). SUS304L (nickel content 9.0-13.0% by weight, chromium content 18.0-
20.0% by weight, iron content 63.90% by weight or more), S
US316 (nickel content 10.0-14.0 wt%, chromium content 16.0-18.0 wt%, iron content 61.85 wt% or more), SUS316L (nickel content 12.0-15. 0% by weight, chromium content 16.0
~ 18.0% by weight, iron content 60.90% by weight or more),
SUH309 (nickel content 12.0-15.0 wt%, chromium content 22.0-24.0 wt%, iron content 57.73 wt% or more), SUS309S (nickel content 12.0-15. 0% by weight, chromium content 22.0
~ 24.0% by weight, iron content 57.845% by weight or more), SUH310 (nickel content 19.0 ~ 22.
0% by weight, chromium content 24.0 to 26.0% by weight, iron content 51.18% by weight or more), SUS310S (nickel content 19.0 to 22.0% by weight, chromium content 2)
4.0-26.0% by weight, iron content 51.345% by weight
Above), but are not limited thereto.

[0008] The reactor in the present invention is not limited to the polymerization tank alone, but includes all parts in contact with a substance involved in the reaction, such as a reaction mixture and / or a reaction by-product and / or a raw material. Contains. Specific examples thereof include, but are not limited to, a raw material dissolving tank, a polymerization tank, a reaction liquid stirring blade, a reflux tower, a polymer pump gear pump, and piping connecting these.

In the present invention, the electropolishing treatment applied to the surface of the liquid contacting part of the reaction apparatus is a method in which a material to be polished is electrolyzed in an electrolytic solution as an anode to selectively dissolve microscopic projections on the surface of the material. It is. Examples of the electrolytic solution to be used include a phosphoric acid-sulfuric acid mixture, a phosphoric acid-sulfuric acid-chromic acid mixture, a perchloric acid-acetic anhydride mixture, a perchloric acid-ethanol mixture, a phosphoric acid-oxalic acid mixture, and a phosphoric acid-citric acid. A mixed solution is exemplified, but a mixed solution of phosphoric acid and sulfuric acid and a mixed solution of phosphoric acid and sulfuric acid and chromic acid are preferably used.

The electropolishing conditions are not particularly limited, but the voltage is preferably 1 to 50 V, more preferably 3 to 20 V.
V, the current density is preferably 1 to 200 A / dm2, more preferably 3 to 100 A / dm2, the processing temperature is preferably 10 to 150C, more preferably 30 to 100C, and the processing time is preferably 1 to 30 minutes. More preferably, 3 to 2
0 minutes.

As a pre-treatment for performing the electrolytic polishing treatment, a mechanical polishing treatment such as a buff polishing may be performed. Further, as the post-treatment, washing with water, washing with acid, washing with alkali, washing with phenol and / or washing with acetone, or washing with a combination of two or more of these are preferably carried out. The washing may be performed at room temperature or may be performed while heating to a temperature higher than room temperature.

The aromatic-aliphatic copolycarbonate according to the present invention comprises a structural unit derived from an aromatic dihydroxy compound represented by the following formula (4):
Consisting of structural units derived from an aliphatic dihydroxy compound represented by the formula, is a random, block, or alternating copolymer, and has excellent impact resistance, excellent heat resistance, and an excellent balance of physical properties of refractive index and Abbe number. Material.

Embedded image (X in the above formula (4) is

Embedded image Wherein R ₃ and R ₄ are a hydrogen atom, a carbon atom of 1
10 to 10 alkyl groups or phenyl groups, and R ₃ and R
₄ may combine to form a ring. R ₁ and R ₂ are a hydrogen atom, an alkyl group having 1 to 10 carbon atoms or halogen, and R ₁ and R ₂ may be the same or different.
Further, m and n represent the number of substituents and are integers of 0 to 4. )

Embedded image

In the present invention, the molar ratio (4) / (5) of the structural units derived from the aromatic dihydroxy compound and the aliphatic dihydroxy compound is 90.
/ 10 to 10/90, more preferably 80/20 to 20/80. That is,
When the molar ratio (4) / (5) of the structural unit derived from the aromatic dihydroxy compound and the aliphatic dihydroxy compound in the aromatic-aliphatic polycarbonate is lower than 10/90, the heat resistance becomes poor, and If it is higher than 10, the photoelastic constant, the water absorption and the like will increase, and the balance between the refractive index and the Abbe number will worsen, which is not preferable as an optical material.

The aromatic-aliphatic copolymer polycarbonate according to the present invention has a weight average molecular weight of 20,000 to 20.
It is preferably 0.000, more preferably 4
It is between 000 and 100,000.

The aromatic-aliphatic copolycarbonate resin is produced by a melt polycondensation method. That is, by using the aromatic dihydroxy compound represented by the above formula (1), the TCDDM represented by the above formula (2), a carbonic acid diester and a catalyst, while removing by-products under heating at normal pressure or reduced pressure, This is to perform melt polycondensation. The reaction is generally carried out in two or more stages.

Specifically, the first-stage reaction is carried out at 120 to 2
The reaction is carried out at a temperature of 60 ° C, preferably 180 to 240 ° C, for 0 to 5 hours, preferably 0.5 to 3 hours. Next, the degree of reaction was increased while increasing the degree of vacuum of the reaction system.
The polycondensation reaction is performed at a temperature of 200 to 300 ° C. under a reduced pressure of not more than mmHg. Further, the reaction device used for performing the above reaction may be a tank type or an extruder type.

As the polymerization catalyst, a basic compound is used. Examples of such a basic compound include an alkali metal compound, an alkaline earth metal compound, a nitrogen-containing compound and the like, and these compounds can be used alone or in combination.

Such alkali metal compounds include:
Organic acid salts of inorganic metals, inorganic acid salts, oxides, hydroxides, hydrides, alcoholates and the like are used, and specifically, sodium hydroxide, potassium hydroxide, cesium hydroxide, lithium hydroxide, hydrogen carbonate Sodium, potassium bicarbonate, lithium bicarbonate, sodium carbonate, potassium carbonate, cesium carbonate, lithium carbonate, sodium acetate,
Potassium acetate, cesium acetate, lithium acetate, sodium stearate, potassium stearate, cesium stearate, lithium stearate, sodium borohydride, lithium borohydride, sodium borohydride, sodium benzoate, potassium benzoate, benzoic acid Cesium, lithium benzoate, disodium hydrogen phosphate, dipotassium hydrogen phosphate, dilithium hydrogen phosphate, disodium phenylphosphate, dipotassium phenylphosphate, dilithium phenylphosphate, dilithium phenylphosphate, bisphenol A
Sodium salt, 2 potassium salt, 2 cesium salt, 2 lithium salt, phenol sodium salt, potassium salt, cesium salt, lithium salt and the like are used.

Further, as the alkaline earth metal compound,
Alkaline earth metal organic acid salts, inorganic acid salts, oxides, hydroxides, hydrides, alcoholates and the like are used, specifically, calcium hydroxide, barium hydroxide, magnesium hydroxide, strontium hydroxide, Calcium bicarbonate,
Barium bicarbonate, magnesium bicarbonate, strontium bicarbonate, calcium carbonate, barium carbonate, magnesium carbonate, strontium carbonate, calcium acetate, barium acetate, magnesium acetate, strontium acetate,
Calcium stearate, barium stearate, magnesium stearate, strontium stearate,
Are used.

As the nitrogen-containing compound, quaternary ammonium hydroxides, quaternary ammonium salts, amines and the like are used. Specifically, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutyl Ammonium hydroxides having alkyl, aryl, araryl groups such as ammonium hydroxide, trimethylbenzyl ammonium hydroxide, etc., tertiary amines such as trimethylamine, triethylamine, dimethylbenzylamine, triphenylamine, dimethylamine, diethylamine, etc. Primary amines such as secondary amine, methylamine and ethylamine; imidazoles such as 2-methylimidazole and 2-phenylimidazole;
Alternatively, basic salts such as ammonia, tetramethylammonium borohydride, tetrabutylammonium borohydride, tetrabutylammonium tetraphenylborate, tetramethylammonium tetraphenylborate and the like are used.

These catalysts are used in an amount of 10 ^{-9 based on} 1 mole of the aromatic dihydroxy compound and the TCDDM in total.
An amount of from 10 to 10 ^-3 mol, preferably from 10 ^-7 to 10 ^-5 mol, is used.

Specific examples of the aromatic dihydroxy compound used in the above formula (1) include bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, and 2,2-bis ( 4-hydroxyphenyl) propane, 2,
2-bis (4-hydroxyphenyl) butane, 2,2-bis (4-
Hydroxyphenyl) octane, bis (4-hydroxyphenyl) phenylmethane, 2,2-bis (4-hydroxy-3-
Methylphenyl) propane, 1,1-bis (4-hydroxy-3
-t-butylphenyl) propane, 2,2-bis (4-hydroxy-3-bromophenyl) propane, 1,1-bis (4-hydroxyphenyl) cyclopentane, 1,1-bis (4-hydroxyphenyl) Cyclohexane, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxy-3,3'-dimethylphenyl ether, 4,4'-dihydroxyphenyl sulfide, 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfide , 4,4'-dihydroxydiphenylsulfoxide,
4,4'-dihydroxy-3,3'-dimethyldiphenylsulfoxide, 4,4'-dihydroxydiphenylsulfone, 4,4'-dihydroxy-3,3'-dimethyldiphenylsulfone and the like. Among these, in particular 2,2-bis (4-hydroxyphenyl) propane, ie bisphenol A or
1,1-bis (4-hydroxyphenyl) cyclohexane (hereinafter referred to as BPZ) is preferred.

Further, diester carbonates include diphenyl carbonate, ditolyl carbonate, bis (chlorophenyl) carbonate, m-cresyl carbonate, dinaphthyl carbonate, bis (diphenyl) carbonate, diethyl carbonate, dimethyl carbonate, dibutyl carbonate, dicyclohexyl carbonate Are used. Of these, diphenyl carbonate is particularly preferred. Diphenyl carbonate is
It is preferably used in an amount of 0.97 to 1.20 mol, particularly preferably 0.99 to 1.10 mol, per 1 mol of the total of the aromatic dihydroxy compound and TCDDM.

In the polycarbonate resin of the present invention, it is preferable to remove or deactivate a catalyst in order to maintain heat stability and hydrolysis stability. In general, a method of deactivating a transesterification catalyst such as an alkali metal or an alkaline earth metal by neutralization by adding a known acidic substance is preferably performed. Specific examples of these substances include inorganic acids such as phosphoric acid, phosphorous acid, hypophosphorous acid, and boric acid, aromatic sulfonic acids such as p-toluenesulfonic acid, and aromatic sulfones such as butyl p-toluenesulfonate. Organic esters such as acid esters, stearic acid chloride, butyric acid chloride, benzoyl chloride, and toluenesulfonic acid chloride, alkyl sulfates such as dimethyl sulfate, and organic halides such as benzyl chloride are preferably used.

After deactivation of the catalyst, a step of devolatilizing and removing low-boiling compounds in the polymer at a pressure of 0.1 to 1 mmHg and a temperature of 200 to 300 ° C. may be provided. A horizontal kneader or a thin film evaporator equipped with eyeglasses or the like is preferably used.

In the present invention, in addition to the above catalyst deactivator, antioxidants, pigments, dyes, reinforcing agents and fillers, ultraviolet absorbers, lubricants, mold release agents, nucleating agents, plasticizers Agents, flow improvers, antistatic agents and the like can be added. Also,
Further, another polycarbonate resin or a thermoplastic resin may be blended and used for the purpose of improving the properties of the resin.

Each of these additives can be mixed with a polycarbonate resin by a conventionally known method. For example, a method in which each component is dispersed and mixed by a high-speed mixer represented by a turnbull mixer, a Henschel mixer, a ribbon blender, or a super mixer, and then melt-kneaded by an extruder, a Banbury mixer, a roll, or the like is appropriately selected.

According to the present invention, an aromatic-aliphatic polycarbonate having excellent color tone can be industrially obtained, and excellent balance of refractive index and dispersion and excellent properties such as impact resistance and heat resistance can be maintained. As a material having an excellent photoelastic constant, it can be stably supplied to plastic optical material applications such as various lenses, prisms and optical disk substrates.

Hereinafter, the present invention will be described specifically with reference to Examples, but the present invention is not limited to the following Examples. The physical properties were measured by the following methods. (1) Weight average molecular weight: GP using chloroform as a solvent
C (Shodex System-21, column temperature 4
(0 ° C.). (2) YI (yellow index): The polymer was press-molded into a disk having a diameter of 50 mm and a thickness of 2 mm, and measured by a color difference meter (SE-2000 manufactured by Nippon Denshoku Industries Co., Ltd.).

Example 1 BPZ 26.8 g (0.10 mol), TCDDM19.
6 g (0.10 mol), diphenyl carbonate
3 g (0.202 mol), sodium bicarbonate 6.0 ×
10 ^-7 mol was placed in a separable flask equipped with a SUS310S stirring blade and a distilling apparatus having a surface roughness Rmax of 0.3 μm or less by an electropolishing treatment, and heated to 180 ° C. under a nitrogen atmosphere. Stirred for minutes. Thereafter, the degree of decompression was adjusted to 150 mmHg, and at the same time,
The temperature was raised to 200 ° C at a rate of ° C / hr to carry out a transesterification reaction. Further, 24
After the temperature was raised to 0 ° C. and maintained at that temperature for 10 minutes, 40
The degree of reduced pressure was reduced to 1 mmHg or less over a period of minutes. The reaction was carried out under stirring for a total of 4 hours, and after completion of the reaction, nitrogen was blown into the reactor to return to normal pressure, and the produced polycarbonate was taken out. Table 1 shows the physical properties of the aromatic-aliphatic copolymerized polycarbonate, and Table 2 shows the physical properties of the apparatus materials.

Example 2 In Example 1, the materials of the stirring blade, the distilling apparatus, and the 300 cc separable flask were subjected to electrolytic polishing to obtain a surface roughness R.
Except that max was changed to 0.2 μm or less, SUS316L was used in exactly the same manner as in Example 1 to obtain a polycarbonate. Table 1 shows the physical properties of the aromatic-aliphatic copolymerized polycarbonate, and Table 2 shows the physical properties of the apparatus materials.

Example 3 In Example 1, the materials of the stirring blade, the distilling device, and the 300 cc separable flask were subjected to electrolytic polishing to obtain a surface roughness R.
Except that max was changed to 0.2 μm or less, SUS304 was used in exactly the same manner as in Example 1 to obtain a polycarbonate. Table 1 shows the physical properties of the aromatic-aliphatic copolymerized polycarbonate, and Table 2 shows the physical properties of the apparatus materials.

Example 4 In Example 1, the amount of BPZ charged was 21.4 g (0.
08 mol) and the charged amount of TCDDM was 23.5 g (0.1
2 mol), and the materials of the stirring blade, the distilling device, and the 300 cc separable flask were subjected to electrolytic polishing to have a surface roughness Rma.
Except that x was changed to 0.5 μm or less to SUS309S, the same operation as in Example 1 was performed to obtain a polycarbonate. Table 1 shows the physical properties of the aromatic-aliphatic copolymerized polycarbonate, and Table 2 shows the physical properties of the apparatus materials.

Comparative Example 1 Example 1 was repeated except that the materials of the stirring blade, the distilling apparatus, and the 300 cc separable flask were changed to SUS310S having a surface roughness Rmax of 12 μm or more, which had not been subjected to electrolytic polishing. The same operation as described above was performed to obtain a polycarbonate. Table 1 shows the physical properties of the aromatic-aliphatic copolymerized polycarbonate, and Table 2 shows the physical properties of the apparatus materials.

Comparative Example 2 Example 1 was repeated, except that the materials of the stirring blade, the distilling device, and the 300 cc separable flask were changed to SUS316L having a surface roughness Rmax of 10 μm or more, which had not been subjected to electrolytic polishing. The same operation as described above was performed to obtain a polycarbonate. Table 1 shows the physical properties of the aromatic-aliphatic copolymerized polycarbonate, and Table 2 shows the physical properties of the apparatus materials.

Comparative Example 3 Example 1 was repeated except that the materials of the stirring blade, the distilling device, and the 300 cc separable flask were changed to SUS304 having a surface roughness Rmax of 10 μm or more, which had not been subjected to electrolytic polishing. The same operation as described above was performed to obtain a polycarbonate. Table 1 shows the physical properties of the aromatic-aliphatic copolymerized polycarbonate, and Table 2 shows the physical properties of the apparatus materials.

Comparative Example 4 In Example 1, the amount of BPZ charged was 21.4 g (0.
08 mol) and the charged amount of TCDDM was 23.5 g (0.1
2 mol), and the materials of the stirring blade, the distilling device, and the 300 cc separable flask were not subjected to the electrolytic polishing treatment, and the surface roughness Rm was determined.
Except that ax was changed to SUS309S of 12 μm or more, the same operation as in Example 1 was performed to obtain a polycarbonate. Table 1 shows the physical properties of the aromatic-aliphatic copolymerized polycarbonate, and Table 2 shows the physical properties of the apparatus materials.

[0038]

[Table 1]

[0039]

[Table 2]

[0040]

According to the present invention, it is possible to synthesize a large amount of an aromatic-aliphatic copolymer polycarbonate having a high Abbe number and a low photoelastic constant and excellent color tone using an inexpensive production apparatus. It can be supplied to a wide range of optical transparent material fields such as various kinds of optical lenses, especially spectacle lenses and prisms requiring particularly excellent color tone, optical disc substrates, optical fibers, and the like.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Yoshinori Isahaya 35-term Towada, Kamisu-cho, Kashima-gun, Ibaraki F-term in Kashima Plant of Mitsubishi Gas Chemical Co., Ltd. (Reference) 2H050 AB50Z AD16 4J029 AA09 AB04 AC02 AD01 AE04 AE05 BB12A BB12B BB13A BB13B BD09A BD10 BE05A BE05B BF14A BF14B BG06X BG08X BG24X BH02 DB07 DB11 HC04A HC05A HC05B KE05 KJ08 LA04

Claims (3)

[Claims] 1. An aromatic dihydroxy compound represented by the following formula (1) and a tricyclo (5.
2.1.0 ^2,6 ) In producing an aromatic-aliphatic copolymer polycarbonate by melt-polycondensing decane dimethanol and a carbonic acid diester, the surface of the wetted part of the reaction apparatus is subjected to electrolytic polishing treatment. A method for producing an aromatic-aliphatic copolymer polycarbonate, comprising using stainless steel containing 8% by weight or more of nickel, 16% by weight or more of chromium, and 50% by weight or more of iron. Embedded image (In the above formula (1), X is Wherein R ₃ and R ₄ are a hydrogen atom, a carbon atom of 1
10 to 10 alkyl groups or phenyl groups, and R ₃ and R
₄ may combine to form a ring. R ₁ and R ₂ are a hydrogen atom, an alkyl group having 1 to 10 carbon atoms or halogen, and R ₁ and R ₂ may be the same or different.
Further, m and n represent the number of substituents and are integers of 0 to 4. ) 2. The aromatic-aliphatic copolymer according to claim 1, wherein the stainless steel contains 8 to 22% by weight of nickel, 16 to 26% by weight of chromium and 50% by weight or more of iron. Method for producing polycarbonate resin. 3. The aromatic-aliphatic copolymer according to claim 1, wherein the aromatic dihydroxy compound is 1,1-bis (4-hydroxyphenyl) cyclohexane represented by the following formula (3). A method for producing a polymerized polycarbonate. Embedded image