JP2974156B2 - Production method of polycarbonate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention provides a polyhydric condensation of a divalent hydroxy compound and a bisaryl carbonate by a transesterification method in the presence of a transesterification catalyst, and further specifies a phosphorus compound. The present invention relates to a method for producing a high-molecular-weight polycarbonate having excellent thermal stability, hue, and hydrolysis stability obtained by adding a hindered phenol compound to deactivate a catalyst residue.

(Prior Art and Problems to be Solved by the Invention) The high molecular weight polycarbonate of the present invention having excellent heat stability, hue, and hydrolysis stability has a wide range of uses, particularly for use in injection molding or as a glass sheet instead of window glass. Having. General-purpose engineering thermoplastics. The interfacial polycondensation method is generally effective for the production of polycarbonate, but has disadvantages such as the use of toxic phosgene and the generation of chloride ions in the polycarbonate produced. In order to eliminate these drawbacks, it has been proposed to produce polycarbonate by an interfacial polycondensation reaction with a special dihydric phenol using liquid trichloromethyl chloroformate which is a dimer of phosgene instead of toxic phosgene. -182336. However, there is only description of 9,9-bis (4-hydroxyphenyl) fluorene which is a special dihydric phenol. Also, obtaining polycarbonate from 2,2-bis (4-hydroxyphenyl) propane using triphosgene instead of toxic phosgene has been described in Angew. Chem.
(Angewandte, Chemie) 99.922 are described in (1987), a reaction mechanism in which phosgene is generated is also proposed. Also, many proposals have been made on how to make the reaction conditions mild to obtain a high-molecular-weight polycarbonate having a good hue when a high-molecular-weight polycarbonate is produced by a transesterification method.

For example, in Japanese Patent Publication No. 47-14742, an initial condensate is formed from an aromatic dioxy compound and a bisaryl carbonate in the presence of a basic catalyst, and then a post-condensation reaction is performed on the initial condensate in the presence of a quaternary ammonium compound. It shows that a polycarbonate having excellent heat stability and hue can be obtained. In JP-B-47-14743, a polycarbonate having a good hue is similarly obtained from an aromatic dioxy compound and bisallyl carbonate using a quaternary ammonium hydroxide as a transesterification catalyst. According to US Pat. No. 4,363,905, a high-molecular-weight polycarbonate having a good hue is obtained by using a phase transfer catalyst in combination with a basic catalyst under basic reaction conditions including a basic catalyst. Or tetraethylphosphonium hydroxide.

However, even if the transesterification reaction is carried out using the above transesterification catalyst, deterioration of the hue cannot be avoided if the polycondensation time is long in order to obtain a high molecular weight polycarbonate. Further, the catalyst residue is not deactivated, and the heat resistance and the hydrolysis resistance are essentially insufficient as shown in Comparative Examples.

(Means for Solving the Problems) The present inventors melt-polycondensate a bisaryl carbonate and a divalent hydroxy compound as a compound for forming a carbonate bond by a transesterification method in the presence of a transesterification catalyst and add a phosphorus compound. By doing so, it is possible to obtain a high molecular weight polycarbonate having excellent heat stability, hue, and hydrolysis stability by using no toxic phosgene, containing essentially no chloride ions, and deactivating the catalyst residue. I came to find it.

The present invention relates to (1) a method in which a polycarbonate obtained by melt-polycondensation of a divalent hydroxy compound and a bisaryl carbonate by a transesterification reaction in the presence of a transesterification catalyst comprising a 2-methylimidazole or dimethylamine borane complex. A method for producing a polycarbonate, comprising adding a compound and a hindered phenol compound each in an amount of 0.03 to 0.3% by weight, and adding them in a weight ratio of 1: 1. (2) The phosphorus compound according to claim 1 has the following structural formula (I) or (I)
A method for producing a polycarbonate, comprising a combination of at least two or three or more selected from the compounds represented by I), (III), (IV), and (V).

(3) A method for producing a polycarbonate, wherein the hindered phenol compound according to claim 1 comprises a hindered phenol compound having the following structural formula (VI).

The transesterification catalyst that can be used in the present invention includes 2-ester
Methyl imidazole or dimethylamine borane complexes are mentioned.

In addition, typical examples of the divalent hydroxy compound include the following compounds. 2,2-bis- (4-hydroxyphenyl) propane, 2,2-bis- (4-hydroxyphenyl) butane, 2,2-bis- (4-hydroxyphenyl)
-4-methylpentane, 2,2-bis- (4-hydroxyphenyl) octane, 4,4'-dihydroxy-2,2,2-triphenylethane, 2,2-bis- (3,5-dibromo- 4-hydroxyphenyl) propane, 2,2-bis- (4-hydroxy-3-methylphenyl) propane, 2,2-bis- (4
-Hydroxy-3-isopropylphenyl) propane,
2,2-bis- (4-hydroxy-3-sec.butylphenyl) propane, 2,2-bis- (3,5-dimethyl-4-hydroxyphenyl) propane, 2,2-bis- (4-hydroxy -3-tert-butylphenyl) propane, 1,1 '
-Bis- (4-hydroxyphenyl) -p-diisopropylbenzene, 1,1'-bis- (4-hydroxyphenyl) -m-diisopropylbenzene, 1,1-bis- (4-
(Hydroxyphenyl) cyclohexane and the like.
Further, two or three or more selected from the above
It is also possible to produce a copolymerized polycarbonate in which a divalent hydroxy compound is combined.

Further, the structural formula (I) used in the present invention is tridecyl phosphite, the structural formula (II) is tris (4-nonylphenyl phosphite), and the structural formula (III) is tris (2,4-
Di-t-butylphenyl) phosphite, structural formula (IV)
Is bis (2,6-di-t-butyl-4-methylphenyl)
Pentaerythritol-di-phosphite), and the structural formula (V) is tetrakis (2,4-di-t-butylphenyl)
−4,4′-biphenylenediphosphonite, having the structural formula (V
I) is preferably octadecyl-3- (3 ', 5'-di-t-butyl-4-hydroxyphenyl) propionate. Representative examples of bisaryl carbonates include diphenyl carbonate, bis (2,4-dichlorophenyl) carbonate, bis (2,4,6-trichlorophenyl) carbonate, bis (2-cyanophenyl) carbonate and bis (2-cyanophenyl) carbonate. Examples include bisaryl carbonates having unsubstituted and nuclear substituents such as (o-nitrophenyl) carbonate and ditolyl carbonate.

The process of the present invention is carried out by subjecting a divalent hydroxy compound such as bisphenol A to a melt polycondensation reaction with a bisaryl carbonate by a transesterification method using a catalyst selected from a transesterification catalyst.

The temperature at which this reaction proceeds ranges from above 100 ° C to about 300 ° C. Preferably it is in the range of 130 ° C to 280 ° C.
If the temperature is lower than 130 ° C., the reaction rate becomes slow, and if it exceeds 280 ° C., side reactions tend to occur.

The transesterification catalyst used as the catalyst is 10 ^-1 mol to 10 ^-5 mol based on the divalent hydroxy compound present in the reaction system.
A mole is required, but preferably from 10 ^-2 to 10 ^-4 mole. When the amount is less than 10 ^-5 mol, the catalytic action is small, and the polymerization rate of the polycarbonate is slow. When the amount is 10 ^-1 mol or more, the rate of remaining in the polycarbonate produced as a catalyst becomes high, which leads to deterioration of the physical properties of the polycarbonate. At any time, tridecyl phosphite, tris (4-nonylphenyl phosphite), tris (2,4-di-t-butylphenyl) phosphite, bis (2,6-di-t-butyl-4-methyl) Phenyl) pentaerythritol-di-
Phosphite, tetrakis (2,4-di-t-butylphenyl) -4,4'-biphenylenediphosphonite and octadecyl-3- (3 ', 5'-di-t-butyl-4-hydroxyphenyl) Propionate is added to the polycarbonate, and the total amount of phosphorus compound added and the hindered phenol compound are each 0.03% to 0.3% by weight based on the total amount of the polymer. The total amount of the phosphorus compound to be added and the weight ratio of the hindered phenol compound to be added are 1: 1. If the addition amount is 0.03% by weight or less, it has no effect as a stabilizer and adversely affects the heat resistance and hydrolysis resistance of the polycarbonate. On the other hand, if it exceeds 0.3% by weight, the mechanical properties of the polycarbonate are adversely affected.

The polymer thus obtained is used as a general engineering plastic material, but is particularly exposed to high-temperature and high-humidity conditions such as outdoor lighting equipment, window glass, outdoor applications such as fences, microwave ovens, tableware, tanks, and transport pipes. Suitable as a material for use.

In addition, the present invention is applicable to heat-sensitive elements such as electric blankets and carpets, various hoses, tubes, hot melt adhesives, and the like.

Although the present invention has been described with reference to examples, the present invention is not limited to these examples.

Example 1 Example 1 228 parts by weight of 2,2-bis (4-hydroxyphenyl) propane, potassium borohydride (10 ⁻³ mol% based on the charged dihydroxy compound), diphenyl carbonate 214
After adding 1 part by weight and stirring at 180 ° C. for 1 hour under nitrogen, the temperature was gradually raised to 250 ° C., and the pressure in the system was reduced to 2 mmHg. Subsequently, the temperature was raised and reacted at 280 ° C. and 0.5 mmHg for 2 hours to obtain a polycarbonate. This polycarbonate is almost colorless and transparent, and the intrinsic viscosity [η] measured at 20 ° C. in methylene chloride solution is 0.438 and [η] = 1.11 × 10 ⁻⁴ (v)
^0.82 [Encyclopedia of Polymer Science and Technology, Vol. 10, p. 732, 1969 John
Wiley and Sons, Inc .; Encyclopedia of
Polymer Science and Technology Vol 10 P732; Jo
hn Wiley & Sons Inc (1969)] was 24,300. 0.127 g of tris (4-nonylphenyl phosphite), 0.127 g of tris (2,4-di-t-butylphenyl) phosphite and octadecyl-3 were added to 254 g of the polycarbonate thus obtained.
-0.254 g of (3 ', 5'-di-t-butyl-4-hydroxyphenyl) propionate is mixed with a tumbler blender (Matsui Seisakubi SKB-50; SKB-50), and the mixture is mixed with a twin-screw extruder (Haake Butler Product HBI System). 90; HAAKE Buchler Product HBI System90)
And extruded into pellets. As an evaluation of heat resistance, the thermal decomposition behavior was measured with a differential thermogravimetric analyzer (manufactured by Rigaku Denki Co., Ltd.) in a nitrogen stream at a heating rate of 10 ° C./min. The decomposition onset temperature (T _d ) was 430 ° C., the temperature at which the weight loss reached 5% (T ₅ ) was 470 ° C., and the temperature at which the weight loss reached 10% (T ₁₀ ) was 485 ° C.

In addition, to evaluate hydrolysis resistance, 50
A sheet having a thickness of mm × 50 mm × 0.6 mm was prepared, suspended in a constant temperature / humidity chamber at 90 ° C. and 100% RH, and a decrease in molecular weight due to hydrolysis was measured. After 30 days under the conditions of 90 ° C. and 100% RH (relative humidity), the retention ratio of the molecular weight to the initial molecular weight was 89.0%, and the sheet was colorless and transparent, and no abnormality was observed.

Example 2 22.8 g of 2,2-bis (4-hydroxyphenyl) propane
(0.1 mol) and 0.164 g of 2-methylimidazole (2 × 10
^-2 mol) and 21.4 g (0.1 mol) of diphenyl carbonate, and the mixture is stirred at 180 ° C for 1 hour under nitrogen, and then gradually heated to 250 ° C.
℃, the pressure in the system was reduced to 2 mmHg, and Tris (4
-Nonylphenyl phosphite) 0.0125 g, tetrakis (2,4-di-t-butylphenyl) -4,4'-biphenylenediphosphonite 0.0125 g and octadecyl-3-
0.025 g of (3 ', 5'-di-tert-butyl-4-hydroxyphenyl) propionate was added. Estimated relative solution viscosity obtained from the stirring torque during this addition (polymer concentration: 0.5 g / 100 ml, 20 ° C, methylene chloride solvent)
Was 1.17, and the relative solution viscosity obtained by actually sampling a small amount of a part of the polymer was 1.18. Continue to heat up
The mixture was reacted at 280 ° C. and 0.5 mmHg for 2 hours to obtain a polycarbonate. This polycarbonate is almost colorless and transparent,
The intrinsic viscosity [η] measured at 20 ° C. in a methylene chloride solution is 0.519 and [η] = 1.11 × 10 ⁻⁴ (v) ^0.82 [Encyclopedia of Polymer Science and Technology, Vol. 10, page 732, 1969 John Wiley and Sons Ink; Encyclopedia of Polymer S
cience and Technology Vol 10 P732; John Wiley & Sons
Inc (1969)].
Was 29,900.

Example 3 Under exactly the same conditions as in Example 1, a dimethylamine borane complex (10 ^-2 ml% based on the charged dihydroxy compound) was added instead of sodium borohydride, and a reaction was carried out to obtain a polycarbonate. . 0.084 g of tridecyl phosphite and bis (2,6-di-t-butyl-4-) were added thereto.
0.084 g of methylphenyl) pentaerythritol-di-phosphite, 0.084 g of tetrakis (2,4-di-t-butylphenyl) -4,4'-biphenylenediphosphonite and octadecyl-3- (3 ', 5' -Di-t-butyl-4-
0.254 g of (hydroxyphenyl) propionate was added, and the mixture was formed into pellets in the same manner as in Example 1 to evaluate heat resistance and hydrolysis resistance. The results are shown in Table 1.

Example 4 114 parts by weight of 2,2-bis (4-hydroxyphenyl) propane (50 mol%), 2,2-bis (4-hydroxy-3-t)
-Butylphenyl) propane 170 parts by weight (50 mol%),
214 parts by weight of diphenyl carbonate, 4-dimethylaminopyridine (10 ^-2 ml based on the charged dihydroxy compound)
%) And reacted under the same conditions as in Example 1 to obtain a polycarbonate copolymer. 0.127 g of tris (4-nonylphenyl phosphite) and tetrakis (2,4
-Di-t-butylphenyl) -4,4'-biphenylenediphosphite 0.127 g and octadecyl-3- (3 ', 5'-
0.254 g of di-tert-butyl-4-hydroxyphenyl) propionate was added, and the mixture was formed into pellets in the same manner as in Example 1.
Heat resistance and hydrolysis resistance were evaluated. The results are shown in Table 1.

Example 5 2,2.8 g of 2,2-bis (4-hydroxyphenyl) propane
(0.1 mol), bis (2,4,6-trichlorophenyl) carbonate 42.1 g (0.1 mol), dimethylaminopyridine 0.
0122g (10 ^-4 mol) under nitrogen, 180 ° C. 1 hour After stirring for similarly tris (4-nonylphenyl Example 2 when the relative solution viscosity was warmed reached 1.19 while the pressure was gradually reduced (Phosphite) 0.0125 g, tri (2,4-di-t-butylphenyl) phosphite 0.0125 g and octadecyl-3-
The reaction was carried out by adding 0.025 g of (3 ', 5'-di-t-butyl-4-hydroxyphenyl) propionate. Table 1 shows the hue, viscosity average molecular weight, thermal decomposition behavior and hydrolysis behavior of the obtained polymer.

(Comparative example) Comparative example 1 Tris (4- (4-) was added to the polycarbonate obtained in Example 1.
Nonylphenyl phosphite) was added, and heat resistance and hydrolysis resistance were evaluated. The results are shown in Table 1.

Comparative Example 2 For the purpose of comparison in Example 2, as a known catalyst, lithium hydroxide which is an alkali metal hydroxide was used in an amount of 10 ^-3 mol% based on 2,2-bis (4-hydroxyphenyl) propane.
The reaction was carried out without using particularly tris (4-nonylphenylphosphite).

The obtained polymer showed a high value of 26,500 as an average molecular weight, but was pale yellow and pyrolysis started at 375 ° C and 430 ° C
At a 10% weight loss. After 30 days in a hydrolysis test at 90 ° C. and 100% RH, the retention of the average molecular weight was only 65.3%. The test sheet became cloudy and many small white spots (including some voids) occurred on the entire surface. The conversion was remarkable. These results are shown in Table 1.

(Effects of the Invention) As shown in the results in Table 1, by adding a specific phosphorus compound and a specific hindered phenol compound to an aromatic polycarbonate polymer, heat resistance and hydrolysis resistance of the obtained resin composition are obtained. And can be used in various fields as engineering plastic materials.

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-43924 (JP, A) JP-A-61-163930 (JP, A) JP-A-3-163161 (JP, A) JP-A-2- 99561 (JP, A) JP-A-63-15842 (JP, A) JP-A-62-141066 (JP, A) JP-A-1-245049 (JP, A) JP-A-63-92643 (JP, A) JP-B-58-12303 (JP, B2) JP-B-62-10579 (JP, B2)

Claims (3)

(57) [Claims] 1. A phosphorus compound on a polycarbonate obtained by melt-polycondensation of a divalent hydroxy compound and a bisaryl carbonate by transesterification in the presence of a transesterification catalyst comprising a 2-methylimidazole or dimethylamine borane complex. And a hindered phenol compound in an amount of 0.03 to 0.3% by weight, respectively, and adding them at a weight ratio of 1: 1. 2. The phosphorus compound according to claim 1 has the following structural formula (I), (II), (III), (IV) or (V)
A method for producing a polycarbonate, comprising a combination of at least two kinds or three or more kinds selected from the compounds represented by the formula: 3. A method for producing a polycarbonate, wherein the hindered phenol compound according to claim 1 comprises a hindered phenol compound having the following structural formula (VI).