JP3102592B2 - Method for producing polycarbonate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a polycarbonate by a transesterification method.

[0002]

2. Description of the Related Art Polycarbonate resins are conventionally produced by an interfacial polymerization method using phosgene and a bishydroxy compound. However, phosgene is highly toxic and has many manufacturing problems. As a production method not using phosgene, melt polycondensation utilizing a transesterification reaction is known, and various catalysts have been proposed for this method. For example, KBH ₄ (Japanese Unexamined Patent Application Publication No.
No. 28336), BeO (JP-A-63-179926).
No.), phenylphosphoric acid (JP-A-58-173125)
), An electron-donating phosphorus compound (JP-A-3-54223).
No.) are known.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to melt-polycondensate a bishydroxy compound and a bisaryl carbonate in the presence of a catalyst of a specific phosphorus compound to obtain a high-molecular-weight, An object of the present invention is to provide a polycarbonate having excellent heat stability.

[0004]

According to the present invention, there is provided a process for producing a polycarbonate, which comprises melt-polycondensing a bishydroxy compound and a bisaryl carbonate in the presence of a phosphorus compound catalyst represented by the following formula:

Embedded image (Wherein R ₁ , R ₂ and R ₃ are an alkyl group having 1 to 25 carbon atoms, an aryl group having 6 to 25 carbon atoms, an alkyloxy group having 1 to 25 carbon atoms, or an aryloxy having 6 to 25 carbon atoms) Represents a group).

In the present invention, bis- (4-hydroxyphenyl) methane, 1,1-bis- (4-hydroxyphenyl) ethane, 1,2-bis- (4-hydroxyphenyl) are used as the bishydroxy compound. ) Ethane, 2,2-bis- (4-hydroxyphenyl) propane, 2,2-bis- (4-hydroxyphenyl) butane, 2,2-bis- (4-hydroxyphenyl) octane, bis- (4- (Hydroxyphenyl) phenylmethane, bis- (4-hydroxyphenyl) diphenylmethane, 2,2-bis- (3,5-dibromo-4-hydroxyphenyl) propane, 1,1-bis- (4-hydroxyphenyl) cyclohexane, Bis- (4-hydroxyphenyl) phenylmethylmethane, 4,4′-dihydroxydiphenyl ether, 4,4'-dihydroxydiphenyl ketone, 4,4'-dihydroxydiphenyl sulfide, 4,4'-dihydroxydiphenyl sulfoxide, 4,4'-dihydroxydiphenyl sulfone and the like. Further, these bishydroxy compounds are used as a main component, and a part thereof is replaced with an aromatic compound containing two phenolic hydroxyl groups such as hydroquinone, resorcin, 2,6-dihydroxynaphthalene, and 4,4′-dihydroxybiphenyl. May be used.

In the present invention, the bisaryl carbonate to be used is diphenyl carbonate, bis (p-chlorophenyl) carbonate, bis (o-chlorophenyl) carbonate, bis (p-nitrophenyl) carbonate, bis (o-nitro) Examples thereof include unsubstituted and diaryl carbonates having a nuclear substituent such as phenyl) carbonate and ditolyl carbonate.

The amount of the bisaryl carbonate to be used is theoretically 1 mol per 1 mol of the bishydroxy compound.
Use 1.1 moles.

In the present invention, the phosphorus compound used as a catalyst includes triphenyl phosphate, tri-p
-Tolyl phosphate, tri-o-tolyl phosphate, triethyl phosphate, tri-n-propyl phosphate, triisopropyl phosphate, tri-n-
Phosphates such as butyl phosphate, and triphenylphosphine oxide, tri-p-tolylphosphine oxide, tri-o-tolylphosphine oxide, triethylphosphine oxide, tri-n-
Propyl phosphine oxide, triisopropyl phosphine oxide, tri-n-butyl phosphine oxide and the like can be mentioned.

[0009] The amount of the phosphorus compound used is 50 to 20,000 ppm, preferably 100 to 5,000 ppm, based on the bishydroxy compound. Usage is 50
If it is less than ppm, the reaction will be slow, and if it exceeds 20,000 ppm, the residual amount in the produced polymer will be undesirably increased.

The addition of the phosphorus compound, even at the beginning of the reaction,
It may be at the time when the temperature is raised to obtain a uniform solution of the monomer. It can also be added by dissolving in an inert solvent such as phenol or toluene. Since the monooxy compound is liberated with the progress of the reaction, the temperature is gradually raised, and the reaction system is decompressed to complete the reaction.

[0011]

According to the present invention, a tough, almost colorless and transparent polycarbonate having a high molecular weight, a narrow molecular weight distribution, and no toxic phosgene can be produced.

[0012]

Embodiments of the present invention will be described below. (Measurement method) Each physical property value shown in the examples of the present invention was measured by the following method. (1) Molecular weight: The weight average molecular weight (Mw) and the number average molecular weight (Mn) were measured in terms of polystyrene using a GPC apparatus SC-8010 system manufactured by Tosoh Corporation. (2) Glass transition temperature (Tg): S manufactured by Seiko Denshi Kogyo
It measured from the inflection point temperature using SC-5200 type DSC apparatus. (3) Thermal decomposition temperature; SSC-520 manufactured by Seiko Denshi Kogyo
Using a 0-type TGA device, the temperature of the sample was increased in nitrogen at 10 ° C./min, and the temperature (T ₃ ) at which 3% weight loss was measured.

EXAMPLE 1 22.83 g of 2,2-bis- (4-hydroxyphenyl) propane (hereinafter referred to as bisphenol A)
1 mol) and 22.71 g (0.106 mol) of diphenyl carbonate (hereinafter referred to as DPC) were added to a 100 ml SUS316 reaction tank, and after substitution with nitrogen, the mixture was heated to 150 ° C. under a nitrogen atmosphere. When both monomers became a homogeneous solution, 0.5 ml of a toluene solution containing 10.1 mg of triphenyl phosphate (440 ppm based on bisphenol A) was added to the reaction vessel. After stirring at 150 ° C for 30 minutes, the temperature was raised to 200 ° C and the system
The pressure was kept at rr. Thereafter, the reaction temperature was raised to 270 ° C. over 3 hours, and the phenol produced was distilled off while gradually increasing the degree of vacuum in the system. Finally,
The reaction was carried out at 0.1 Torr and 270 ° C. for 1.5 hours, and the formed phenol was distilled off. The obtained polycarbonate was tough and almost colorless and transparent. The physical properties of the obtained polycarbonate are shown in Table 1.

Example 2 228.3 g (1 mol) of bisphenol A and DPC
227.1 g (1.06 mol) was added to a 1 L reaction vessel made of SUS316, and after substitution with nitrogen, the mixture was heated to 150 ° C. under a nitrogen atmosphere. When both monomers became a homogeneous solution, 5 ml of a toluene solution containing 110 mg of triphenyl phosphate (480 ppm based on bisphenol A) was added to the reaction vessel. The temperature was raised to 225 ° C. in 50 minutes, and after the temperature was raised, the inside of the system was kept at a reduced pressure of 100 Torr. Thereafter, the reaction temperature was raised to 270 ° C. over 4 hours, and phenol produced was distilled off while gradually increasing the degree of vacuum in the system. 1.5 hours at 280 ° C. at 3 Torr,
The reaction was carried out at 280 ° C. for 2 hours at 0.5 Torr, and the formed phenol was distilled off. Thereafter, nitrogen was introduced to extrude the produced polycarbonate from a hole at the bottom of the reaction vessel. The obtained polycarbonate was tough and almost colorless and transparent. The physical properties are shown in Table 1.

Example 3 In Example 1, tri-n-butyl phosphate 1 was used in place of triphenyl phosphate as the phosphorus compound.
Except for using 1.5 mg, polymerization was carried out in the same manner to obtain a nearly colorless and transparent polycarbonate. The physical properties are shown in Table 1.

Example 4 In Example 1, triphenylphosphine oxide 1 was used in place of triphenylphosphate as the phosphorus compound.
Except for using 1.5 mg, polymerization was carried out in the same manner to obtain a nearly colorless and transparent polycarbonate. The physical properties are shown in Table 1.

Example 5 A substantially colorless and transparent polycarbonate was obtained in the same manner as in Example 1, except that 11 mg of tri-n-butylphosphine oxide was used instead of triphenyl phosphate as the phosphorus compound. The physical properties are shown in Table 1.

Comparative Example 1 In Example 1, except that 0.9 mg (40 ppm) of triphenyl phosphate was used as a phosphorus compound.
Polymerization was performed in the same manner. Although polycarbonate is obtained,
It was a very fragile polymer. The physical properties are shown in Table 1.

[Table 1]

Continuation of front page (58) Field surveyed (Int.Cl. ⁷ , DB name) C08G 64/30

Claims (1)

(57) [Claims] 1. A process for producing a polycarbonate, comprising melt-polycondensing a bishydroxy compound and a bisaryl carbonate in the presence of a phosphorus compound catalyst represented by the following formula: Embedded image (Wherein R ₁ , R ₂ and R ₃ are an alkyl group having 1 to 25 carbon atoms, an aryl group having 6 to 25 carbon atoms, an alkyloxy group having 1 to 25 carbon atoms, or an aryloxy having 6 to 25 carbon atoms) Represents a group.)