JPH04268365A - Polycarbonate resin solution for forming cast film - Google Patents

Abstract

PURPOSE:To prepare the title soln. excellent in film-forming properties in casting by dissolving a specific random copolycarbonate resin in an org. solvent. CONSTITUTION:The title soln. is prepd. by dissolving a random copolycarbonate resin comprising 35-65mol% structural units of formula I and 65-35 mol% structural units of formula II and having a viscosity-average mol.wt. of 15,000-100,000 in an org. solvent. In these formulas, R<8> to R<8> are each H, halogen, or 1-4C alkyl; and A is 1-10C linear, branched, or cyclic alkylidene, aryl-substd. alkylidene, aryl, or sulfonyl. An example of the structural unit of formula I is one derived from a dihydric phenol e. g. 2, 2-bis(4-hydroxyphenyl) propane (bisphenol A) or 1,1-bis (4-hydroxyphenyl) cyclohexan; while an example of the structural unit of formula II is one derived from bis(4-hydroxyphenyl) ether.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polycarbonate resin solution for cast film formation, and more particularly to a polycarbonate resin solution for cast film formation having a specific structure and excellent cast film forming properties, and a method for producing the same.

0002

[Prior Art] Films are produced by pouring a resin solution onto the surface of a drum or belt in the form of a film using the casting method, and drying the solvent with hot air, or by immersing rolls, plates, and other various parts in the resin solution. It is well known to coat or line such surfaces. however,
In general, polycarbonate resin solutions begin to become cloudy after being left for 3 to 4 days, requiring operations such as preparing a low-concentration solution or redissolving them, which has the drawback of poor production efficiency in casting film formation. In addition, the resulting films and coatings have the disadvantage of being susceptible to stress cracks and having low mechanical strength.

0003

[Means for Solving the Problems] The present invention solves these problems by using a specific polycarbonate resin. That is, the present invention is based on the following general formula (1)
and (2) have the structural units represented by (1) and (
2) The molar ratio of the structural units represented by is 35/65
~65/35, and the viscosity average molecular weight is 15,000
A polycarbonate resin solution for cast film formation prepared by dissolving a random co-polycarbonate resin with a molecular weight of ~100,000 in an organic solvent.

0004

[Chemical formula 3]

(In the formula, R1 to R8 represent hydrogen, halogen, or an alkyl group having 1 to 4 carbon atoms, and A is a linear, branched, or cyclic alkylidene group having 1 to 10 carbon atoms, or an aryl-substituted alkylene group. group, aryl group, and sulfonyl group) and their production method.

The configuration of the present invention will be explained below. The polycarbonate resin used in the present invention is a dihydric phenol represented by the following general formulas (3) and (4).

[
0007

[C4]

[0008] is copolymerized with phosgene, carbonate ester, or chloroformate to have structural units of the general formulas (1) and (2) randomly, and a viscosity average molecular weight of 15,000 to 100,000. , preferably 20,
000 to 40,000. The reaction molar ratio of the dihydric phenols of general formulas (3) and (4) is 35/65 to 65/35. If this molar ratio is outside the range, the polycarbonate resin will become cloudy or the solution stability will decrease. Random copolymerization results in more uniform microdispersion than in block copolymers, and improves properties such as optical properties, solution stability, and stress cracking. If the viscosity average molecular weight is less than 15,000, the strength of the film obtained by casting will not be sufficient, and if it is more than 100,000, the production efficiency by casting will decrease.

Further, as the dihydric phenol compound represented by the general formula (3) used as a raw material for the copolycarbonate resin of the present invention, bis(4-hydroxyphenyl)
Methane, 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-dimethylphenyl)propane, 2,2-bis(
4-hydroxy-3,5-dibromophenyl)propane, 2,2-bis(4-hydroxy-3,5-dichlorophenyl)propane, 2,2-bis(4-hydroxy-3
-methylphenyl)propane (dimethylbisphenol A; DMBPA), 2,2-bis(4-hydroxy-3-bromophenyl)propane, 2,2-bis(4
-hydroxy-3-chlorophenyl)propane, 1,1
-bis(4-hydroxyphenyl)-1-phenylethane, bis(4-hydroxyphenyl)diphenylmethane, bis(4-hydroxyphenyl) sulfone, etc. Among them, 2,2-bis(4-hydroxyphenyl) Propane, 1,1-bis(4-hydroxyphenyl)cyclohexane, 1,1-bis(4-hydroxyphenyl)-1-phenylethane, 2,2-bis(4-hydroxyphenyl)
-hydroxy-3-methylphenyl)propane, bis(
4-hydroxyphenyl) sulfone is preferred, especially 2,2-bis(4-hydroxyphenyl)propane,
1,1-bis(4-hydroxyphenyl)cyclohexane is preferred from the viewpoint of thermal stability.

The dihydric phenol compound represented by the general formula (4) used as a raw material for the co-polycarbonate resin of the present invention includes bis(4-hydroxyphenyl) ether (4,4-dihydroxydiphenyl ether; DH).
PE), bis(3-methyl-4-hydroxyphenyl) ether (3,3'-dimethyl-4,4'-dihydroxydiphenyl ether; DMDHPE), bis(3-
Bromo-4-hydroxyphenyl)ether, bis(3
-chloro-4-hydroxyphenyl)ether, bis(
3,5-dimethyl-4-hydroxyphenyl)ether, bis(3,5-dibromo-4-hydroxyphenyl)
Examples include ether, bis(3,5-dichloro-4-hydroxyphenyl) ether, and among them, bis(
4-hydroxyphenyl)ether is preferred.

[0011] In addition, a terminal capping agent or a molecular weight regulator is usually used, and these include compounds having a monovalent phenolic hydroxyl group, such as ordinary phenol, p-tert-butylphenol, tribromophenol, etc. Other examples include long-chain alkylphenols, aliphatic carboxylic acid chlorides, aliphatic carboxylic acids, hydroxybenzoic acid alkyl esters, hydroxyphenylalkyl esters, and alkyl ether phenols. The amount used is for all dihydric phenol compounds used.
The amount is in the range of 100 to 0.5 mol, preferably 50 to 2 mol, and it is naturally possible to use two or more kinds of compounds together. Furthermore, a branching agent can be used in combination with the above dihydric phenol compound in an amount of 0.01 to 3 mol%, particularly 0.1 to 1.0 mol%, to produce a branched polycarbonate, which can be used as a branching agent. is phloroglycin, 2,6-dimethyl-2,4,6-tri(4
-hydroxyphenyl)heptene-3,4,6-dimethyl-2,4,6-tri(4-hydroxyphenyl)heptene-2,1,3,5-tri(2-hydroxyphenyl)benzole, 1,1, 1-tri(4-hydroxyphenyl)ethane, 2,6-bis(2-hydroxy-5-
methylbenzyl)-4-methylphenol, α, α
′, α″-tri(4-hydroxyphenyl)-1,3
, 5-triisopropylbenzene, etc., and 3,3-bis(4-hydroxyaryl)oxindole (= isatin bisphenol), 5-chloroisatin, 5,7-dichloroisatin, 5-bromiisatin, etc. is exemplified.

[0012] If desired, various additives conventionally known to polycarbonate resins can be added to the polycarbonate resin used in the present invention, such as reinforcing materials, fillers, stabilizers, ultraviolet absorbers, Antistatic agent, lubricant,
Examples include mold release agents, dyes, pigments, other flame retardants, and elastomers for improving impact resistance. For example, phosphorous acid or phosphite is particularly suitable as a stabilizer. In addition, examples of mold release agents include esters of mono- or polyhydric alcohols of saturated fatty acids, such as stearyl stearate,
Suitable examples include behenyl behenate, pentaerythritol tetrastearate, and dipentaerythritol hexaoctoate. Organic or inorganic fillers such as glass powder, glass beads, synthetic mica or fluorinated mica, zinc oxide, carbon fibers, especially glass fibers including those with a fiber diameter of 2 μm or less, zinc oxide whiskers, stainless steel fibers, Kevlar fibers, etc. Examples of reinforcing agents and elastomers include MBS, MABS, MAS, and others. Furthermore, ordinary resins such as polycarbonate, polyester carbonate, and polyarylate can also be suitably used depending on the purpose.

[0013] The solvent used for the polycarbonate resin solution in the present invention may be any solvent as long as it dissolves the polycarbonate resin of the present invention and has appropriate volatility. Naturally, halogenated solvents such as chlorobenzene and methylene chloride are also suitable. Can be used for In consideration of safety and health during casting, non-halogen solvents, particularly hydrocarbon solvents such as toluene, xylene, and ethylbenzene, are preferred. The concentration of the solution is usually 1 to 30% by weight, preferably 5 to 20% by weight. Unlike general polycarbonate resins, the polycarbonate resin of the present invention exhibits high solubility even in non-halogenated solvents such as toluene, and has the advantage of high solution stability.

[0014]

[Example] Example 1 3.7 kg of sodium hydroxide was dissolved in 42 liters of water, and while keeping the temperature at 20°C, bisphenol A was added to the solution.
(BPA), 3.23 kg of 4,4'-dihydroxydiphenyl ether (DHPE), and 8 g of hydrosulfite (HD) were dissolved. Add 28 liters of methylene chloride (MC) to this and add pt-butylphenol (PTBP) while stirring.
Add 148g, then add 3.5g of phosgene (PG)
kg over 60 minutes. After phosgene injection,
The reaction solution was emulsified by vigorous stirring, and after emulsification, 8 g of triethylamine (TEA) was added and stirred for about 1 hour to polymerize. The polymerization solution was separated into an aqueous phase and an organic phase, and the organic phase was neutralized with phosphoric acid. After repeating water washing until the pH of the washing solution became neutral, 35 liters of isopropanol was added.
The polymer was precipitated. The precipitate was filtered and then dried to obtain a white powdery polycarbonate resin. Table 1 shows the results of measuring the physical properties of this polycarbonate resin.

Comparative Example 1 Example 1 except that 7.3 kg of BPA was used instead of 3.65 kg of BPA and 3.23 kg of DHPE.
I did the same thing. The results are shown in Table 1.

Comparative Example 2 (1) Production of polycarbonate oligomer 1.6 kg of sodium hydroxide was dissolved in 1.8 liters of water.
BPA 3.65kg, HD 4 while keeping at 20℃
g was dissolved. Add 14 liters of MC to this, add 64 g of PTBP while stirring, and then add 2 liters of PG.
．． 4 kg was blown in 40 minutes. After the PG injection was completed, only the MC solution containing the polycarbonate oligomer was collected. The analysis results of the obtained oligomer MC solution were as follows. Oligomer concentration (Note 1)
29.4 Weight % terminal Cl group concentration (Note 2)
6.5% terminal phenolic hydroxyl group concentration (Note 3) 0.01% (Note 1
) Measured by evaporation to dryness (Note 2) Neutralization titration of aniline hydrochloride obtained by reacting with aniline with 0.2N NaOH aqueous solution (Note 3) Color development when dissolved in titanium tetrachloride acetic acid solution at 546 nm
The oligomer solution obtained by a method beyond colorimetry is hereinafter referred to as oligomer solution A.

(2) Production of polycarbonate oligomer In the above (1), BPA was replaced with 4,4'-dihydroxydiphenyl ether (DHPE) 3.23k
The procedure was the same as in (1) except that g was changed. The analysis results of the obtained oligomer MC solution were as follows. Oligomer concentration
26.0 wt% terminal Cl group concentration
7.0% Terminal phenolic hydroxyl group concentration 0.01%
The oligomer solution obtained by the above method is hereinafter referred to as oligomer solution B.

(3) Production of block copolymerized polycarbonate Oligomer solution A, oligomer solution B, 4 liters of MC, and 20 g of PTBP were supplied to a reactor. Na to this
Add a solution consisting of 1.0 kg of OH and 18 liters of water, stir vigorously to emulsify the reaction solution, and after emulsification, 8 g
of TEA was added, and stirring was continued for about 1 hour to polymerize. Separate the polymerization solution into an aqueous phase and an organic phase, neutralize the organic phase with phosphoric acid, repeat water washing until the pH of the washing solution becomes neutral, and then add 35 liters of isopropanol to precipitate the polymer. Ta. The precipitate was filtered and then dried to obtain a white powdery polycarbonate resin. Table 1 shows the results of measuring the physical properties of this polycarbonate resin.

Examples 2 to 5, Comparative Examples 3 to 4 In the same manner as in Example 1, PCs having the respective compositions shown in Table 1 were obtained. Table 1 shows the results of measuring the physical properties of these polycarbonate resins.
Shown below.

[0020]

[Table 1]

[0021]

Effects of the Invention The polycarbonate resin according to the present invention has high solubility in non-halogen solvents and can be used in cast molding as a non-halogen solvent solution, thereby reducing health and safety problems during cast molding. Furthermore, since the polycarbonate resin solution has excellent solution stability, the productivity of film by cast molding is improved. Further, the film obtained using the solution of the present invention has the advantage of having excellent resistance to stress cracks and the like, and high surface strength.

Claims (7)

[Claims] Claim 1: It has structural units represented by the following general formulas (1) and (2), and the molar ratio of the structural units represented by (1) and (2) is 35/65 to 65/35. and the viscosity average molecular weight is 15,000 to 100,000
A polycarbonate resin solution for cast film formation prepared by dissolving a random co-polycarbonate resin in an organic solvent [Formula 1] (wherein, R1 to R8 are hydrogen, halogen, or a carbon atom having 1 to 1 carbon atoms)
4 represents an alkyl group, and A represents a linear, branched, or cyclic alkylidene group, an aryl-substituted alkylidene group, an aryl group, or a sulfonyl group having 1 to 10 carbon atoms. ) 2. The solution according to claim 1, wherein the organic solvent is a non-halogen solvent. 3. The solution according to claim 1, wherein the resin solution has a concentration of 1 to 30% by weight. 4. The structural unit represented by the general formula (1) is 2,2-bis(4-hydroxyphenyl)propane (bisphenol A), 1,1-bis(4-hydroxyphenyl)-cyclohexane, 1 ,1-bis(4-
hydroxyphenyl)-1-phenylethane, 2,2-
The solution according to claim 1, which is derived from a dihydric phenol selected from the group consisting of bis(3-methyl-4-hydroxyphenyl)-propane and bis(4-hydroxyphenyl) sulfone. 5. The solution according to claim 1, wherein the structural unit represented by general formula (2) is derived from bis(4-hydroxyphenyl)-ether. 6. The solution according to claim 1, wherein the polycarbonate resin has a viscosity average molecular weight of 20,000 to 40,000. [Claim 7] The following general formulas (3) and (4)
) A random copolymer having a viscosity average molecular weight of 15,000 to 100,000 is prepared by copolymerizing dihydric phenols represented by (3) and (4) in a molar ratio of 35/65 to 65/35. A method for producing a polycarbonate resin suitable for cast film production, characterized by producing a polycarbonate resin [Formula 2] (wherein, R1 to R8 are hydrogen, halogen, or a carbon atom having 1 to 1 carbon atoms)
4 represents an alkyl group, and A represents a linear, branched, or cyclic alkylidene group, aryl-substituted alkylene group, aryl group, or sulfonyl group having 1 to 10 carbon atoms. )