JP2000095853A - Branched polycarbonate and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a new branched polycarbonate having a hindered phenol structure in a part of the molecule and to provide a method for producing the branched polycarbonate. SOLUTION: This branched polycarbonate is produced by reacting bisphenols with polyhydric phenols to be a branching agent, a monohydric phenol to be a molecular weight modifier and a compound represented by the formula [R1 denotes t-butyl group; R2 to R4 denote each hydrogen, a 1-9C alkyl group, a 3-12C cycloalkyl group, benzyl group or a phenyl ester group; (a) and (b) denote each an integer of 0-7] and phosgene. The monohydric phenol is used in an amount of 0.5-10 mol% based on the total bisphenols and the compound represented by the formula is used in an amount of 0.0005-0.5 mol% based on the total bisphenols. The intrinsic viscosity of the polycarbonate is 0.3-1.0 dL/g.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a novel branched polycarbonate and a method for producing the same. For more information,
The present invention relates to a branched polycarbonate having a partially hindered phenol structure in the molecule.

[0002]

2. Description of the Related Art Conventionally, polycarbonate has been known for its transparency,
Widely used as engineering plastics with excellent mechanical strength and thermal stability. Polycarbonate can be molded by various molding methods, especially when manufacturing large molded products by blow molding or extrusion molding,
Newtonian fluidity is a problem, and a phenomenon called sagging due to its own weight is likely to occur, and it has been sometimes difficult to obtain a desired molded product.

[0003] Therefore, in order to prevent sagging, a polycarbonate exhibiting a large non-Newtonian fluidity is preferable, and a branched polycarbonate is known as a polycarbonate having a structural viscosity suitable for such properties.

[0004] Specifically, phloroglucin and 4,6-dimethyl-2,4,6-tri- (4-hydroxyphenyl) -heptane
Methods for producing a branched polycarbonate using a branching agent having three or more functional groups such as -2 are known, and are disclosed, for example, in JP-B-44-17149 and JP-B-47-23918. Although these branched polycarbonates have improved moldability based on the improvement of the non-Newtonian fluidity, problems such as a decrease in impact resistance and a problem of coloring have occurred, and improvement has been required.

[0005] Therefore, techniques for solving the above problems by limiting the number of branching agents and optimizing the polymerization method are known, for example, Japanese Patent Publication Nos. 3-15658, 3-42288 and 4-42288.
69178, Japanese Patent Publication No. 6-84459, and Japanese Patent Publication No. 7-103235. However, these methods have no effect of preventing the branched polycarbonate itself from being oxidized and degraded by heating during molding, and the improvement effect was not sufficient under molding conditions exceeding 300 ° C. due to the high cycle.

On the other hand, a hindered phenol-based antioxidant is generally used as a primary antioxidant (radical antioxidant) for the purpose of preventing thermal deterioration or coloring during plastic molding or long-term use. However, conventional antioxidants have low molecular weight, so they are easily volatilized during molding, and bleed-out (sticky surface) may occur on the surface during long-term use of the molded product. In particular,
When molding a heat-resistant resin such as polycarbonate having a molding temperature exceeding 250 ° C., volatilization is remarkable, and in extrusion molding, it may cause adhesion to a vent portion or generation of bubbles in a molded product, and improvement has been required. .

For this reason, a high molecular weight antioxidant having a hindered phenol structure at the molecular terminal is known, and for example, Japanese Patent Application Laid-Open No. 10-139875 has been disclosed. When this polymer type antioxidant was added to a conventional branched polycarbonate, it was effective in improving the hue, but was not sufficiently effective in improving the impact resistance.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to provide a branched polycarbonate which is less colored during high-temperature molding and has excellent impact resistance.

[0009]

Means for Solving the Problems The present inventors have made intensive studies to solve the conventional problems, and as a result, added a small amount of special hindered phenols during the production of polycarbonate to cause a reaction. It has been found that a branched polycarbonate having excellent properties and a high antioxidant effect can be obtained, and based on this finding, the present invention has been completed.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS That is, the present invention provides bisphenols, polyhydric phenols as a branching agent, monohydric phenols as a molecular weight regulator, and a compound represented by the following general formula (1) in the presence of an aqueous alkali solution and an organic solvent. A polycarbonate obtained by reacting a compound represented by the above with phosgene, wherein a monohydric phenol is 0.5 to 10 mol based on all bisphenols.
The present invention provides a branched polycarbonate having an intrinsic viscosity of 0.3 to 1.0 dl / g using 0.0005 to 0.5 mol% of the compound of the formula (1), and a process for producing the same.

[0011]

Embedded image

[0012] (wherein, R ₁ represents a t- butyl group .R ₂ ~
R ₄ is hydrogen, an alkyl group having 1 to 9 carbon atoms, and 3 to 1 carbon atoms.
2 represents a cycloalkyl group, a benzyl group, or a phenyl ester group. a and b represent an integer of 0-7. )

The branched polycarbonate of the present invention can be obtained by the same production method as the conventional polycarbonate production method except that a specific amount of a special hindered phenol which mainly functions as a molecular weight regulator or a terminal stopper is used. Can be done.

That is, it can be produced by a known method used in producing polycarbonate from bisphenols, that is, by a direct reaction (phosgene method) between bisphenols and phosgene.

The starting bisphenols from which the branched polycarbonate of the present invention is derived are specifically 4,4'-biphenyldiol, 1,1'-bi-2-naphthol, bis (4-hydroxyphenyl) methane, bis (4-hydroxyphenyl) methane, (4-hydroxyphenyl) ether, bis (4-hydroxyphenyl) sulfone, bis (4-hydroxyphenyl) sulfoxide, bis (4-hydroxyphenyl) sulfide, bis (4
-Hydroxyphenyl) ketone, 1,1-bis (4-hydroxyphenyl) ethane, 2,2-bis (4-hydroxyphenyl) propane (bisphenol A; BPA), 2,2-bis (4-hydroxyphenyl) ) Butane, 1,1-bis (4-hydroxyphenyl) cyclohexane (bisphenol Z)
BPZ), 2,2-bis (4-hydroxy-3,5-dibromophenyl) propane, 2,2-bis (4-hydroxy-3,5-
Dichlorophenyl) propane, 2,2-bis (4-hydroxy-3-bromophenyl) propane, 2,2-bis (4-hydroxy-3-chlorophenyl) propane, 2,2-bis (4-
(Hydroxy-3-methylphenyl) propane, 2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane,
1,1-bis (4-hydroxyphenyl) -1-phenylethane, bis (4-hydroxyphenyl) diphenylmethane, 2,2-bis (4-hydroxyphenyl) hexafluoropropane, α, ω-bis [2- ( p-hydroxyphenyl) ethyl] polydimethylsiloxane, α, ω-bis [3- (o-hydroxyphenyl) propyl] polydimethylsiloxane, 9,9-bis (4-hydroxyphenyl) fluorene, 2,2-bis ( 4-hydroxy-3-allylphenyl)
Propane, 4,4 '-[1,4-phenylenebis (1-methylethylidene)] bisphenol, 4,4'-[1,3-phenylenebis (1-methylethylidene)] bisphenol, 1,1,3- Trimethyl-3-[(4-hydroxy) phenyl] -5-hydroxyindane, 3,3,3 ', 3'-tetramethyl-2,3,2', 3'-tetrahydro- (1,1'-spiro Biindene) -6,6′-diol and the like. These can be used in combination of two or more.

Of these, 2,2-bis (4-hydroxyphenyl) propane is particularly preferred from the viewpoint of mechanical strength, reactivity, economy and the like.

The branching agent of the present invention includes phloroglucin, 2,4,4'-trihydroxybenzophenone, 2,4,4'-
Trihydroxyfenyl ether, 2,2-bis (2,4-dihydroxyphenyl) propane, 2,2 ', 4,4'-tetrahydroxydiphenylmethane, 2,4,4'-trihydroxydiphenylmethane, 2,6- Dimethyl-2,4,6-tri (4-hydroxyphenyl) -heptene-3,4,6-dimethyl-2,4,6-tri
(4-hydroxyphenyl) -heptane-2,2,6-bis (2-hydroxy-5-methylbenzyl) -4-methylphenol, 2,
6-bis (2-hydroxy-5-isopropylbenzyl) -4-isopropylphenol, tetrakis (4-hydroxyphenyl) methane, α, α ', α "-tris (4-hydroxyphenyl) -1,3,5- Triisopropylbenzene, 1,1-bis (4-
Hydroxyphenyl) -1- [4- (4-hydroxyphenyl)
Isopropylphenyl] ethane, 1,1,1-tris (4-hydroxyphenyl) methane, 1,1,1-tris (4-hydroxyphenyl) ethane, 1,1,1-tris (4-hydroxyphenyl) propane, 1,1,1-tris (2-methyl-4-hydroxyphenyl) methane, 1,1,1-tris (2-methyl-4-hydroxyphenyl) ethane, 1,1,1-tris (3-methyl- 4-hydroxyphenyl) methane, 1,1,1-tris (3-methyl-4
-Hydroxyphenyl) ethane, 1,1,1-tris (3,5-dimethyl-4-hydroxyphenyl) methane, 1,1,1-tris (3,5-dimethyl-4-hydroxyphenyl) ethane, 1,
1-tris (3-chloro-4-hydroxyphenyl) methane,
1,1,1-tris (3-chloro-4-hydroxyphenyl) ethane, 1,1,1-tris (3,5-dichloro-4-hydroxyphenyl) methane, 1,1,1-tris (3, 5-dichloro-4-hydroxyphenyl) ethane, 1,1,1-tris (3-bromo-4-hydroxyphenyl) methane, 1,1,1-tris (3-bromo-4-
Hydroxyphenyl) ethane, 1,1,1-tris (3,5-dibromo-4-hydroxyphenyl) methane, 1,1,1-tris (3,5-dibromo-4-hydroxyphenyl) ethane, 1,1 ,
1-tris (3-fluoro-4-hydroxyphenyl) methane, 1,1,1-tris (3-fluoro-4-hydroxyphenyl) ethane, 1,1,1-tris (3,5-difluoro-4- Examples thereof include (hydroxyphenyl) methane, 1,1,1-tris (3,5-difluoro-4-hydroxyphenyl) ethane, and 1,1,1-tris (4-hydroxyphenyl) -1-phenylmethane.

Of these, 1,1,1-tris (4-hydroxyaryl) alkanes are preferred in view of reactivity and coloring of the obtained polymer. Specifically, 1,1,1-tris (4-
Hydroxyphenyl) methane, 1,1,1-tris (4-hydroxyphenyl) ethane, 1,1,1-tris (4-hydroxyphenyl) propane, 1,1,1-tris (2-methyl-4-hydroxy Phenyl) methane, 1,1,1-tris (2-methyl-4-hydroxyphenyl) ethane, 1,1,1-tris (3-methyl-4
-Hydroxyphenyl) methane, 1,1,1-tris (3-methyl-4-hydroxyphenyl) ethane, 1,1,1-tris (3,
5-dimethyl-4-hydroxyphenyl) methane, 1,1,1-tris (3,5-dimethyl-4-hydroxyphenyl) ethane,
1,1,1-tris (3-chloro-4-hydroxyphenyl) methane, 1,1,1-tris (3-chloro-4-hydroxyphenyl)
Ethane, 1,1,1-tris (3,5-dichloro-4-hydroxyphenyl) methane, 1,1,1-tris (3,5-dichloro-4-hydroxyphenyl) ethane, 1,1,1- Tris (3-bromo-4-
Hydroxyphenyl) methane, 1,1,1-tris (3-bromo
-4-hydroxyphenyl) ethane, 1,1,1-tris (3,5-
Dibromo-4-hydroxyphenyl) methane, 1,1,1-tris (3,5-dibromo-4-hydroxyphenyl) ethane,
1,1-tris (3-fluoro-4-hydroxyphenyl) methane, 1,1,1-tris (3-fluoro-4-hydroxyphenyl) ethane, 1,1,1-tris (3,5-difluoro- 4-hydroxyphenyl) methane, 1,1,1-tris (3,5-difluoro-4-hydroxyphenyl) ethane, 1,1,1-tris (4-hydroxyphenyl) -1-phenylmethane and the like are exemplified. You. Among them, 1,1,1-tris (4-hydroxyphenyl)
Ethane is most preferred because of its reactivity and ease of handling.

The branching agent used in the branched polycarbonate of the present invention can be used arbitrarily as long as it retains the characteristics as a branched polycarbonate. In consideration of the range in which non-Newtonian properties are exhibited, the content is preferably 0.1 to 3.0 mol% based on all bisphenols.

The compound of the general formula (1) incorporated into the branched polycarbonate skeleton of the present invention is a polyhydric phenol having a hindered phenol structure, and functions mainly as a molecular weight regulator. The compound of the general formula (1) is a phenol having at least one t-butyl group at the ortho position of phenol.

Specifically, pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl)
Propionate], pentaerythrityl-tetrakis [3- (3-methyl-5-t-butyl-4-hydroxyphenyl)
Propionate], pentaerythrityl-tetrakis [4- (3,5-di-t-butyl-4-hydroxyphenyl) butanoate], pentaerythrityl-tetrakis [4- (3-
Methyl-5-t-butyl-4-hydroxyphenyl) butanoate], pentaerythrityl-tetrakis [(3,5-di-
t-butyl-4-hydroxyphenyl) acetate], pentaerythrityl-tetrakis [(3-methyl-5-t-butyl-4-hydroxyphenyl) acetate], pentaerythrityl-tetrakis [3- (3-phenyl- 5-t-butyl-4-
Hydroxyphenyl) propionate]. These polyphenols may be used in combination of two or more.

Among them, pentaerythrityl-tetrakis [3- (3,5-di-
(t-butyl-4-hydroxyphenyl) propionate is more preferred.

The amount of the compound represented by the general formula (1) is 0.0005 to 0.5 mol% based on the bisphenols which induce a polycarbonate skeleton. If it is less than 0.0005 mol%, the effect of preventing coloring is small, and if it exceeds 0.5 mol%, the impact resistance is reduced. In consideration of the balance between the coloring prevention effect and the impact resistance, the content is preferably in the range of 0.001 to 0.3 mol%.

The compound of the general formula (1) of the present invention is a unique polyhydric phenol, and generally has a molecular weight controlling effect equivalent to that of a monohydric phenol which is a molecular weight regulator in the production of polycarbonate. In addition, since the hydroxyl group remains at the molecular terminal, it has a function as a primary antioxidant. When the compound of the general formula (1) of the present invention is used in the phosgene method, the ratio acting as a molecular weight regulator depends on the reaction conditions and substituents, but is approximately 20 to 98% of the amount used. .

In the present invention, the compound represented by the general formula (1) may sometimes react as a component constituting the main skeleton in addition to bonding to the molecular terminal of the polycarbonate. In addition, the polycarbonate terminal at the time of polycarbonate production by the phosgene method contains tens to hundreds of ppm of a phenolic hydroxyl group, a carbamate group, a chloroformate group or the like as a terminal group in addition to a structure to which a molecular weight modifier is bonded. Such a terminal group is usually 5 to the entire terminal group.
% Or less, it does not substantially affect the performance as an antioxidant.

Further, the present invention is characterized in that the polyhydric phenol represented by the general formula (1) is used in combination with a conventional monohydric phenol molecular weight regulator. Pt-butylphenol, cumylphenol, tribromophenol, pn-
Alkyl phenols such as octyl phenol and pn-stearyl phenol; alkyl ether phenols such as pn-butoxy phenol and pn-octyl oxyenol;
and hydroxybenzoic acid alkyl esters such as n-butyl p-hydroxybenzoate, n-octyl p-hydroxybenzoate, and n-stearyl p-hydroxybenzoate.

The monohydric phenol used as the molecular weight regulator is added so that the branched polycarbonate falls within the preferred molecular weight range as a molding material. The amount added is 0.5 to 10 mol% based on the total bisphenols. Is 1 to 5 mol%.

In the phosgene method, an acid binder is usually used. As the acid binder, for example, pyridine or a hydroxide of an alkali metal such as sodium hydroxide or potassium hydroxide is used as an aqueous solution. Further, if necessary, a small amount of an antioxidant such as sodium sulfite or hydrosulfite may be added.

In the phosgene method, a solvent inert to the reaction is used. Examples of the solvent include chlorinated hydrocarbons such as dichloromethane, 1,2-dichloroethane, 1,1,2,2-tetrachloroethane, chloroform, 1,1,1-trichloroethane, carbon tetrachloride, monochlorobenzene, and dichlorobenzene. Aromatic hydrocarbons such as benzene, toluene, xylene, and ethylbenzene; ether compounds such as diethyl ether; and two or more of these organic solvents can be used as a mixture. Further, if desired, ethers other than the above, ketones, esters,
A solvent having an affinity for water, such as nitriles, may be used as long as the mixed solvent system is not completely compatible with water.

The reaction is usually carried out at 0 to 150 ° C., preferably at 5 to 150 ° C.
Suitably the temperature is in the range of 40 ° C. The reaction time depends on the reaction temperature, but is usually 0.5 minutes to 10 hours, preferably 1 minute to 2 hours. During the reaction, it is desirable to maintain the pH of the reaction system at 10 or more.

When the branched polycarbonate of the present invention is produced by the phosgene method, the compound of the general formula (1) is added after the completion of the phosgenation reaction of bisphenols, and the chloroformate derived from the molecular weight regulator and the starting bisphenol is added. A preferred method is to bring the body into an emulsified state, add a polymerization catalyst thereto, and carry out a polymerization reaction.

As the polymerization catalyst, tertiary amines such as trimethylamine, triethylamine, tributylamine, tripropylamine, trihexylamine, tridecylamine, N, N-dimethylcyclohexylamine, pyridine, quinoline and dimethylaniline; And quaternary ammonium salts such as benzylammonium chloride, tetramethylammonium chloride and triethylbenzylammonium chloride.

When molded, the branched polycarbonate of the present invention can be prepared by using a conventional antioxidant such as a hindered phenol-based antioxidant, a thioether-based antioxidant, a phosphite-based antioxidant, an ultraviolet absorber, a dye or pigment of any color. Can be blended.

The branched polycarbonate of the present invention has an intrinsic viscosity of 0.3 to 1.0 dl / g from the viewpoint of strength and moldability. When the intrinsic viscosity is 1.0 dl / g or more, the moldability is difficult, and when the intrinsic viscosity is less than 0.3 dl / g, the mechanical strength decreases.

[0035]

Next, the present invention will be described in more detail by way of examples, which should not be construed as limiting the present invention.

Example 1 A 61-liter aqueous solution of 8.8% (w / v) sodium hydroxide was charged with 2,2-bis (4-hydroxyphenyl) propane (BPA, 40 mol
l) 9.12 kg, 61.2 g of 1,1,1-tris (4-hydroxyphenyl) ethane (hereinafter, TPE, 0.2 mol) and 10 g of hydrosulfite were added and dissolved. Methylene chloride 36
Of phosgene 5.
3kg was blown in over 50 minutes. After blowing, the following structure

[0037]

Embedded image

Pentaerythrityl-tetrakis [3- (3,
5-di-t-butyl-4-hydroxyphenyl) propionate (AO-60 manufactured by Asahi Denka Kogyo KK, hereinafter A60, 0.004 mol)
4.71g and pt-butylphenol (PTBP, 1.52mol)
228 g was added, and the mixture was vigorously stirred to emulsify the reaction solution. After emulsification, 20 ml of triethylamine was added, and the mixture was stirred at about 25 ° C. for about 1 hour to carry out polymerization.

After the completion of the polymerization, the reaction solution is separated into an aqueous phase and an organic phase, the organic phase is neutralized with phosphoric acid, and the washing solution has a conductivity of 10 μS.
After repeated washing with water until the temperature became below, the polymerization liquid was dropped into warm water at 45 ° C. to precipitate a polymer. The precipitate was filtered and dried to obtain a powdery polymer. This polymer had an intrinsic viscosity [η] of 0.59 dl / g at a temperature of 20 ° C. of a solution having a concentration of 0.5 g / dl using methylene chloride as a solvent.

The result of analysis from the infrared absorption spectrum of the above polymer, the absorption due to a carbonyl group in a position near 1770 cm ^-1, observed absorption by ether bond position near 1240 cm ^-1, was confirmed to have a carbonate bond Was. The monomers in the branched polycarbonate were extracted with acetone and measured by GPC analysis.
It was less than 20 ppm. The obtained branched polycarbonate powder was extruded at 320 ° C. using a vented 50 mm extruder,
A molten pellet was obtained.

Example 2 The procedure of Example 1 was repeated except that TPE was changed to 122.4 g (0.4 mol). The intrinsic viscosity [η] of the obtained polymer is 0.72
dl / g.

Example 3 The procedure of Example 1 was repeated, except that 58.4 g of 1,1,1-tris (4-hydroxyphenyl) methane (hereinafter, TPM, 0.2 mol) was used instead of TPE. The intrinsic viscosity [η] of the obtained polymer was 0.57 dl / g.

Example 4 The procedure of Example 1 was repeated except that 47.12 g (0.04 mol) of A60 was used. The intrinsic viscosity [η] of the obtained polymer is 0.58 dl
/ G.

Example 5 TPE was added to 244.8 g (0.8 mol) and A60 to 141.4 g (0.12 mol).
In addition, phenol (hereinafter PH, 2.4 mol) instead of PTBP 225.
Except having changed to 6 g, it carried out similarly to Example 1. The intrinsic viscosity [η] of the obtained polymer was 0.83 dl / g.

Example 6 TPE was added to 24.48 g (0.08 mol) and A60 to 2.36 g (0.002 mol).
In l), the same procedure as in Example 1 was carried out except that PTBP was changed to 120 g (0.8 mol). Intrinsic viscosity [η] of the obtained polymer
Was 0.80 dl / g.

Example 7 The same procedure as in Example 1 was carried out except that TPE was added before blowing A60 into phosgene. The intrinsic viscosity [η] of the obtained polymer was 0.60 dl / g.

Example 8 Instead of TPE, phloroglucin (hereinafter PHG, 0.2 mol)
Was carried out in the same manner as in Example 1 except that 25.2 g was used. The intrinsic viscosity [η] of the obtained polymer was 0.58 dl / g.

Example 9 Except that 96 g of α, α ′, α ″ -tris (4-hydroxyphenyl) -1,3,5-triisopropylbenzene (hereinafter, TPTB, 0.2 mol) was used instead of TPE. Was performed in the same manner as in Example 1. The intrinsic viscosity [η] of the obtained polymer is 0.58
dl / g.

Comparative Example 1 The same operation as in Example 1 was carried out except that A60 was not used.
The intrinsic viscosity [η] of the obtained polymer was 0.59 dl / g.

Comparative Example 2 The same operation as in Example 2 was carried out except that A60 was not used.
The intrinsic viscosity [η] of the obtained polymer was 0.72 dl / g.

Comparative Example 3 The same procedure was performed as in Example 3 except that A60 was not used.
The intrinsic viscosity [η] of the obtained polymer was 0.58 dl / g.

Comparative Example 4 The same operation as in Example 5 was carried out except that A60 was not used.
The intrinsic viscosity [η] of the obtained polymer was 0.84 dl / g.

Comparative Example 5 The same operation as in Example 6 was carried out except that A60 was not used.
The intrinsic viscosity [η] of the obtained polymer was 0.80 dl / g.

Comparative Example 6 A solution of the branched polycarbonate obtained in Comparative Example 1 in 20% w / v methylene chloride resin was added to the resin raw material BPA at a concentration of 0.2%.
01 mol% of A60 was added and uniformly blended. Thereafter, the same precipitation, drying and extrusion as in Example 1 were performed.

Comparative Example 7 A 20 w / v% methylene chloride resin solution of the branched polycarbonate obtained in Comparative Example 1 was added to a resin raw material BPA at a concentration of 0.2%.
1 mol% of A60 was added and uniformly blended. Thereafter, the same precipitation, drying and extrusion as in Example 1 were performed.

Comparative Example 8 BPA was added to 610 ml of an 8.8% (w / v) aqueous sodium hydroxide solution.
(0.4 mol) 91.2 g and hydrosulfite 0.1 g were added and dissolved. Add 360 ml of methylene chloride to this and add
53 g of phosgene was blown in over a period of 50 minutes while stirring at a temperature of ° C.

After the completion of blowing, A60 (0.05 mol) 58.9 g
And agitate vigorously to emulsify the reaction solution.
Add 0.2 ml of triethylamine and at about 25 ° C.
The mixture was stirred and polymerized for about 1 hour.

The polymer solution was separated into an aqueous phase and an organic phase, the organic phase was neutralized with phosphoric acid, and the washing was repeated until the conductivity of the washing solution became 10 μS or less. Dripping,
The polymer was precipitated. The precipitate was filtered and dried to obtain a powdery polymer. This polymer had an intrinsic viscosity [η] of 0.31 dl / g at a temperature of 20 ° C. of a solution having a concentration of 0.5 g / dl using methylene chloride as a solvent.

The results of the obtained above polymer was analyzed from the infrared absorption spectrum, absorption by carbonyl group at the position in the vicinity of 1770 cm ^-1, observed absorption by ether bond position near 1240 cm ^-1, having a carbonate bond Was confirmed. In addition, absorption derived from a hydroxyl group was observed at a position of 3650 to 3200 cm ^-1 .

When the monomer in the polycarbonate was extracted with acetone and measured by GPC analysis, A60 was 320 pp.
m and BPA were less than 20 ppm. The phenolic hydroxyl group content of this polycarbonate was measured by a colorimetric method and was found to be 1.32% by weight. The polycarbonate-type high molecular weight antioxidant having a hindered phenol structure at the molecular terminal thus obtained is abbreviated as A60P.

The number average molecular weight of A60P was calculated from
6400, and the resin raw material BP was added to the 20 w / v% methylene chloride resin solution of the branched polycarbonate obtained in Comparative Example 1.
0.01 mol% of A60P was added to A and homogeneously blended.
Thereafter, the same precipitation, drying and extrusion as in Example 1 were performed.

Comparative Example 9 The same procedure as in Example 1 was carried out except that 377 g (0.32 mol) of A60 was used. The intrinsic viscosity [η] of the obtained polymer is 0.55 dl /
g.

Comparative Example 10 The same procedure as in Example 8 was carried out except that A60 was not used.
The intrinsic viscosity [η] of the obtained polymer was 0.58 dl / g.

Comparative Example 11 The same operation as in Example 9 was carried out except that A60 was not used.
The intrinsic viscosity [η] of the obtained polymer was 0.55 dl / g.

The compositions and analytical values of the polycarbonate resins of Examples 1 to 9 and Comparative Examples 1 to 11 are shown in Tables 1, 2 and 3. Also, an N value (structural viscosity index) is obtained by using the obtained pellet, and an injection molded product is formed by using the pellet,
The physical properties measured for the YI value (yellow index) and the Izod impact strength are also shown in Tables 1, 2 and 3.

[0066]

[Table 1] Example 1 real 2 real 3 real 4 real 5 real 6 real 7 ────────────────────────────── ───── Bisphenols BPA BPA BPA BPA BPA BPA BPA mol% 40 40 40 40 40 40 40 Branching agent TPE TPE TPM TPE TPE TPE TPE mol% 0.5 1.0 0.5 0.5 2.0 0.2 0.5 Molecular weight regulator PTBP PTBP PTBP PTBP PH PTBP PTBP mol% 3.8 3.8 3.8 3.8 6.0 2.0 3.8 General formula (1) Compound A60 A60 A60 A60 A60 A60 A60 mol% 0.01 0.01 0.01 0.1 0.3 0.005 0.01 Intrinsic viscosity (dl / g) 0.59 0.72 0.57 0.58 0.83 0.80 0.60 YI value 2.0 2.5 2.2 1.8 2.9 2.4 2.3 N value 1.62 1.84 1.62 1.57 1.99 1.35 1.62 Izod impact strength (J / m) 836 812 844 871 780 889 828

[0067]

Table 2 Examples and Comparative Examples Actual 8 Actual 9 Ratio 1 Ratio 2 Ratio 3 Ratio 4 Ratio 5 ──────── Bisphenols BPA BPA BPA BPA BPA BPA BPA mol% 40 40 40 40 40 40 40 Branching agent PHG TPTB TPE TPE TPM TPE TPE mol% 0.5 0.5 0.5 1.0 0.5 2.0 0.2 Molecular weight regulator PTBP PTBP PTBP PTBP PTBP PH PTBP mol% 3.8 3.8 3.8 3.8 3.8 6.0 2.0 General formula (1) Compound A60 A60 --- --- --- --- --- mol% 0.01 0.01 --- --- --- --- --- Intrinsic viscosity (dl / g) 0.58 0.58 0.59 0.72 0.58 0.84 0.80 YI value 2.1 2.2 2.6 3.1 2.7 4.5 2.7 N value 1.61 1.63 1.63 1.84 1.62 2.01 1.31 Izod impact strength (J / m) 834 845 788 739 797 698 856

[0068]

Table 3 Comparative Example Ratio 6 Ratio 7 Ratio 8 Ratio 9 Ratio 10 Ratio 11 ─ Bisphenols BPA BPA BPA BPA BPA BPA mol% 40 40 40 40 40 40 Branching agent TPE TPE TPE TPE PHG TPTB mol% 0.5 0.5 0.5 0.5 0.5 0.5 Molecular weight regulator PTBP PTBP PTBP PTBP PTBP PTBP mol% 3.8 3.8 3.8 3.8 3.8 3.8 Compound of general formula (1) * A60 * A60 * A60P A60 --- --- mol% 0.01 0.1 0.01 0.8 --- --- Intrinsic viscosity (dl / g) 0.58 0.56 0.59 0.55 0.58 0.58 YI value 2.6 2.5 2.3 2.0 2.7 2.8 N value 1.62 1.62 1.62 1.66 1.62 1.62 Izod impact strength (J / m) 793 793 795 786 786 797

The items described in the table are described below. BPA: 2,2-bis (4-human peroxyphenyl) fluoro TPE: 1,1,1-tris (4-human peroxyphenyl) ethane TPM: 1,1,1-tris (4-human peroxyphenyl) methane PHG: fluoroguanosine TPTB : α, α ', α "-tris (4-humanperoxyphenyl) -1,3,5-triisopropylbenzene A60: pentaerythrityl-tetrakis [3- (3,5-cy-t-butyl-4-humanpropyl) [Phenyl) fluorodionate] * A60: A60 was dissolved in a branched polycarbonate solution and blended * A60P: A60 high molecular weight antioxidant prepared in Comparative Example 8 was dissolved and blended in a branched polycarbonate solution PTBP: pt -Phthylphenol PH: Phenol Intrinsic viscosity: The intrinsic viscosity (dl / g) of a 0.5 w / v% methylene chloride resin solution at 20 ° C. was measured with a Huggins constant of 0.45 YI value: 3.2 mm thick Izod injection molded product YI value (yellow index ) Is measured with a color difference meter N value: Using a flow tester, 280 ° C, nozzle diameter 1mm ×
Flow value Q (cm2 / sec) under two conditions of pressure under 10mm condition
Was measured. The time 15.68MPa Q1, and the structural viscosity index by a formula: and Q2 the time 3.92 MPa N value _{= log (Q 1 / Q 2} ) / log (15.68 / 3.92). Izod impact strength: 3.2 mm notched injection molded at 320 ° C
Thick molded articles for Izod were measured for Izod impact strength (J / m) according to ASTM (D256).

[0070]

The branched polycarbonate of the present invention is less deteriorated by heat history at high temperatures and is excellent in hue and impact resistance as compared with the conventional branched polycarbonate. In particular, blow molding, sheet extrusion,
Suitable for injection molding.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Hideki Watanabe 2--12 Kanshu-cho, Toyonaka-shi, Osaka Mitsubishi Gas Chemical Co., Ltd. Osaka Plant F-term (reference) 4J029 AA09 AB01 AC02 AD01 AE01 BB10A BB10B BB12A BB12B BB12C BB13A BB13B BC03A BC09 BD09A BE05A BF14A BG06X BG06Y BH02 BH04 DB07 DB13 DB15 EB03 EB05A FA07 FC02 FC03 FC32 FC33 HA01 HA02 HC01

Claims (7)

[Claims] 1. A bisphenol, a polyhydric phenol serving as a branching agent, a monohydric phenol serving as a molecular weight regulator, and the following general formula (1) in the presence of an aqueous alkali solution and an organic solvent.
Is a polycarbonate obtained by reacting a compound represented by the formula (1) with phosgene, wherein 0.5 to 10 mol% of a monohydric phenol and 0.0005 to 0.5 mol% of a compound of the general formula (1) are used based on all bisphenols. , Intrinsic viscosity 0.3 ~ 1.0d
l / g, branched polycarbonate. Embedded image (Wherein, R ₁ represents a t-butyl group; R _{2 to} R ₄ represent hydrogen,
It represents an alkyl group having 1 to 9 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, a benzyl group, or a phenyl ester group. a
And b represents an integer of 0 to 7. ) 2. The branched polycarbonate according to claim 1, wherein the compound of the general formula (1) is pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate]. 3. The method according to claim 1, wherein the polyhydric phenol serving as a branching agent is 1,1.
The branched polycarbonate according to claim 1, which is a 1,1-tris (4-hydroxyaryl) alkane. 4. The polyhydric phenol which serves as a branching agent is 1,1,
The branched polycarbonate according to claim 1, which is 1-tris (4-hydroxyphenyl) ethane. 5. The branched polycarbonate according to claim 1, wherein the bisphenol is 2,2-bis (4-hydroxyphenyl) propane. 6. The branched polycarbonate according to claim 1, wherein the polyhydric phenol serving as a branching agent is used in an amount of 0.1 to 3.0 mol% based on all bisphenols. 7. A bisphenol and a polyhydric phenol serving as a branching agent are reacted with phosgene in the presence of an aqueous alkali solution and an organic solvent, and then a monohydric phenol serving as a molecular weight regulator and a compound represented by the general formula (1) The method for producing a branched polycarbonate according to claim 1, wherein the compound represented by the formula (1) is added and emulsified, and then a polymerization catalyst is added and the mixture is polymerized.