JP2534694B2 - Polycarbonate resin and its manufacturing method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a novel polycarbonate resin and a method for producing the same. More specifically, the present invention is
For example, the present invention relates to a novel polycarbonate resin having excellent optical properties, which is useful as a material for optical devices, and a method for producing the same.

[Prior Art] Generally, plastic optical materials are
Demand has been increasing in recent years because it is lightweight, has excellent impact resistance, does not require a polishing step, and can be mass-produced for aspherical lenses.

Among them, polycarbonate resin is excellent in transparency, heat resistance, molding dimensional accuracy, and mechanical strength, which are essential physical properties for optics, and is a very promising resin for this application. However, the commonly used 2,2-bis (4
Polycarbonate made from -hydroxyphenyl) propane (commonly known as bisphenol A) and a polycarbonate-based resin having a carbon skeleton similar to this include a aromatic ring with large polarization anisotropy in the main chain, and therefore injection molding and melting The product obtained by spinning has large birefringence due to molecular orientation, and shows optical anisotropy due to this, which is a serious defect as a resin for a material for precision optical equipment.

Here, the birefringence is defined by a numerical value obtained by subtracting the refractive index viewed from the direction perpendicular to the resin refractive index viewed from the direction in which stress is applied during molding.

[Problems to be Solved by the Invention] The present invention is to provide a novel polycarbonate-based resin having no optical anisotropy, which is useful as a material for optical devices.

[Means for Solving the Problems] The present inventors have found that a polycarbonate polymer synthesized from a dihydric phenol having a carbon skeleton of bisphenol A has an essential defect in a polycarbonate having a structure having a benzene ring as a main chain. In order to lower the value of birefringence, the result of diligent research into the relationship between the structure and the optical anisotropy showed that the side-chain substituent that allows the ring to freely rotate on a benzene ring of a size comparable to the benzene ring of the main chain. It was noted that the orientation of the benzene ring of the main chain can be hindered by introducing as.

In order to realize this idea, as long as steric hindrance does not occur in the polycondensation reaction, as many benzene rings as possible are introduced into the dihydric phenol of the bisphenol A skeleton as a raw material, and this is used to reduce the optical anisotropy. The present invention was completed by synthesizing polycarbonate.

That is, the present invention (In the formula, R ¹ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and R ² is an alkyl group having 1 to 5 carbon atoms or a phenyl group.) And has an intrinsic viscosity. Is 0.
Polycarbonate resin with 3 dl / g or more and The present invention provides a method for producing a polycarbonate resin of the formula (I), which comprises reacting a carbonic acid ester forming compound with a dihydric phenol represented by

In the present invention, the above general formula (II) used as a raw material
A divalent phenol compound having a carbon skeleton of bisphenol A having a structure represented by the formula (1) has a bulky (bulky) benzene ring introduced into its side chain when it is polycondensed to form a polycarbonate. Although it reduces anisotropic orientation with respect to stress during molding,
Furthermore, since the bulky phenyl group is introduced only on one side of the phenol group involved in the condensation reaction, the degree of steric hindrance is small in the polycarbonate synthesis reaction and the central carbon atom is also one of the two bonds. It is characterized in that only a single bulky phenyl group is bonded, the main chain of the polycarbonate polymer is made relatively free to rotate, and the deterioration of molding processability is minimized.

The compounds corresponding to the formula (II) can all be used as the polycarbonate resin of the present invention, but specific examples include 1- (4-methoxyphenyl) -1,1-
Bis (3-phenyl-4-hydroxyphenyl) ethane, 1- (4-phenoxyphenyl) -1,1-bis (3
-Phenyl-4-hydroxyphenyl) ethane, 1-
(4-Ethoxyphenyl) -1,1-bis (3-phenyl-4-hydrocyclophenyl) ethane, 1- (4-methoxyphenyl) -1,1-bis (3-phenyl-4-hydroxyphenyl) propane , 1- (4-phenoxyphenyl) -1,1-bis (3-phenyl-4-hydroxyphenyl) propane, 1- (4-methoxyphenyl) -1,1
-Bis (3-phenyl-4-hydroxyphenyl) butane, 1- (4-phenoxyphenyl) -1,1-bis (3
-Phenyl-4-hydroxyphenyl) butane, 1-
(-Methoxyphenyl) -1,1-bis (3-phenyl-
4-hydroxyphenyl) pentane, 1- (4-phenoxyphenyl) -1,1-bis (3-phenyl-4-hydroxyphenyl) hexane, 1- (4-butoxyphenyl) -1,1-bis (3- Phenyl-4-hydroxyphenyl) ethane, 1- (4-methoxyphenyl) -1,1-
Bis (3-phenyl-4-hydroxyphenyl) methane, 1- (4-phenoxyphenyl) -1,1-bis (3
-Phenyl-4-hydroxyphenyl) methane, 1-
(4-Methoxyphenyl) -1,1-bis (3-phenyl-4-hydroxyphenyl) hexane and the like can be mentioned.

In the present invention, a mixture of two or more of these dihydric phenols of the formula (II) at an arbitrary ratio can be used as a raw material. In this case, the polycarbonate resin of the present invention is composed of two or more repeating units. It is composed of a copolymer consisting of

On the other hand, as the carbonate ester-forming compound, in addition to phosgene, any compound can be used as long as it reacts with a hydroxyl group of a dihydric phenol in a transesterification reaction in a reaction system to form a carbonate bond. And bisaryl carbonates such as diphenyl carbonate, di-p-tolyl carbonate, phenyl-p-tolyl carbonate, di-p-chlorophenyl carbonate, and dinaphthyl carbonate.

As a method for producing the polymer of the present invention, known methods used in producing polycarbonate from bisphenol A, for example, a direct reaction of dihydric phenol with phosgene,
Alternatively, a method such as a transesterification reaction between a dihydric phenol and a bisaryl carbonate can be adopted.

In the former direct reaction method of a dihydric phenol and phosgene, the dihydric phenol represented by the general formula (II) is usually reacted with phosgene in the presence of an acid binder and a solvent. As the acid binder, for example, pyridine, hydroxides of alkali metals such as sodium hydroxide and potassium hydroxide, etc. are used, and as the solvent, for example, methylene chloride, chlorobenzene, xylene and the like are used.

Further, in order to accelerate the polycondensation reaction, a catalyst such as a tertiary amine such as triethylamine or a quaternary ammonium salt is used, and in order to adjust the degree of polymerization, a molecular weight of pt-butylphenol or phenylphenol is used. It is desirable to add a regulator to carry out the reaction. If desired, a small amount of an antioxidant such as sodium sulfite or hydrosulfide may be added. The reaction is usually carried out at a temperature in the range of 0 to 150 ° C, preferably 5 to 40 ° C. The reaction time depends on the reaction temperature, but usually 0.5 minutes to 10 hours,
It is preferably 1 minute to 2 hours. During the reaction, the reaction system
It is desirable to keep the pH above 10.

On the other hand, in the latter transesterification method, the above formula (II)
The dihydric phenol represented by and bisaryl carbonate are mixed and reacted at high temperature under reduced pressure. The reaction is usually carried out at a temperature in the range of 150 to 350 ° C, preferably 200 to 300 ° C, and the degree of reduced pressure is preferably 1 m at the end of the reaction.
At a pressure of not more than mHg, phenols derived from the bisaryl carbonate generated by the transesterification are distilled out of the system. Although the reaction time depends on the reaction temperature and the degree of reduced pressure, it is usually about 1 to 4 hours. The reaction is preferably carried out in an atmosphere of an inert gas such as nitrogen or argon, and if desired, the reaction may be carried out by adding the above-mentioned molecular weight modifier or antioxidant.

The polycarbonate resin of the present invention thus obtained is a novel polycarbonate polymer comprising a repeating unit represented by the general formula (I), and has an intrinsic viscosity at a temperature of 20 ° C. using methylene chloride as a solvent. (Η) is 0.3 dl / g or more. If the intrinsic viscosity is less than 0.3 dl / g, the degree of polymerization is too low to sufficiently exert the object of the present invention.

The molding method of the polycarbonate resin of the present invention, a method usually used for molding the polycarbonate resin,
For example, an injection molding method, a compression molding method, a low-link method, which is an eclectic method of injection molding and compression molding, or a micromolding method can be used.

In the molding method, when molding the polycarbonate resin of the present invention, if desired, for example, phosphite esters for preventing coloring and deterioration of transparency, a plasticizer for increasing the melt index value, etc. It can be compounded and molded. Moreover, you may mix and shape | mold another resin.

Examples of the phosphites used in this case include tributyl phosphite, tris (2-ethylhexyl) phosphite, tridecyl phosphite, trisstearyl phosphite, triphenyl phosphite, tricresyl phosphite, and tris ( Nonylphenyl) phosphite, 2-ethylhexyldiphenylphosphite, decyldiphenylphosphite, phenyl-di-2
-Ethylhexyl phosphite, phenyldidecyl phosphite, tricyclohexyl phosphite, distearyl pentaerythrityl diphosphite, diphenylpentaerythrityl diphosphite and the like.

Further, a plasticizer may be added to the polycarbonate resin of the present invention to improve moldability. In this case, it is desirable that the plasticizer does not impair the transparency, for example, alkyl phthalates such as 2-ethylhexyl phthalate, n-butyl phthalate, isodecanyl phthalate, tridecanyl phthalate, heptyl phthalate, nonyl phthalate, 2- Dibasic acid alkyl esters such as ethylhexyl adipate and 2-ethylhexyl sebacate, phosphoric acid alkyl esters such as tributyl phosphate, trioctyl phosphate, tricresyl phosphate, triphenyl phosphate, epoxidized octyl oleate, epoxidized Examples thereof include epoxidized fatty acid esters such as butyl oleate, polyester-based plasticizers, and chlorinated fatty acid esters.

EXAMPLES Next, the present invention will be described in more detail with reference to examples.

Reference Example 1 [1- (4-phenoxyphenyl) -1,1-bis (3-
Synthesis of Phenyl-4-hydroxyphenyl) ethane] 510 g (3 mol) of o-phenylphenol, 212 g (1 mol) of 4'-phenoxyacetophenone, and 9.2 g of mercaptoacetic acid were mixed and dissolved by heating at 60 ° C. , Stir
117 g of sulfuric acid having a concentration of 98% by weight was added and reacted at 70 ° C. for 12 hours. After completion of the reaction, the product was cooled, diluted with methylene chloride (3), and washed with water (2) three times. Then,
Crystals were obtained by adding 500 ml of a 5 N sodium hydroxide aqueous solution and cooling with water. Next, the crystals were washed with methylene chloride, dispersed in water 3, and hydrochloric acid was added until the pH became 1 or less. Then, after filtering the crystals and washing with water,
By recrystallization using a toluene-hexane mixed solvent, 235 g of 1- (4-phenoxyphenyl) -1,1-bis (3-phenyl-4-hydroxyphenyl) ethane
I got

The yield of this product was 44% (vs. 4'-phenoxyacetophenone), and the melting point was 125 to 129 ° C.

In addition, ¹ H-NMN (acetone d ₆ ) δ (ppm) is 2.10 (s3
H), 6.82 (s4H), 6.9 to 7.4 (m17H), 7.54 (d4H),
It was 7.54 (d4H) and the molecular weight (m +) by mass spectrum analysis was 534.

Reference Example 2 [Synthesis of 1- (4-methoxyphenyl) -1,1-bis (3-phenyl-4-hydroxyphenyl) ethane] Instead of 4'-phenoxyacetophenone, 150 g of 4'-methoxyacetophenone (1 mol) ) Was used,
The same procedure as in Reference Example 1 was performed. As a result, 160 g of 1- (4-methoxyphenyl) -1,1-bis (3-phenyl-4-hydroxyphenyl) ethane was obtained. Yield 34% (vs. 4'-
Methoxyacetophenone), melting point 142-145 ° C.

In addition, ¹ H-NMR (acetone d ₆ ) δ (ppm) is 2.21 (s3
H), 3.54 (s 3H), 6.82 (d 2H), 6.92 (d 2H), 6.9
8 (dd 2H), 7.04 to 7.22 (m 6H), 7325 to 7.40 (m 6
H), 7.90 (dd 2H) and 8.1 (dd 2H). The molecular weight (m +) was 472.

Example 1 1- (4 obtained in Reference Example 1 above as a dihydric phenol
-Phenoxyphenyl) -1,1-bis (3-phenyl-
To a solution of 80 g of 4-hydroxyphenyl) ethane dissolved in 500 ml of an aqueous potassium hydroxide solution having a concentration of 1.5 N, 400 ml of methylene chloride, 1.0 g of pt-butylphenol and 2 ml of a 10 wt% aqueous solution of triethylamine as a catalyst are added, While vigorously stirring, phosgene was blown for 20 minutes to carry out the reaction.

After completion of the reaction, the product was diluted with methylene chloride 1 and water 1, 500 ml of 0.01N sodium hydroxide aqueous solution, water 500
ml, 0.01N hydrochloric acid (500 ml) and water (500 ml) in this order. Then, this methylene chloride solution was poured into methanol to obtain a white polymer. This polymer has a concentration of 0.5 g / dl in methylene chloride as a solvent, 0.4 g / dl, and an intrinsic viscosity [η] calculated from a reduced viscosity [η sp / c] of a solution of 0.3 g / dl at 20 ° C. It was 0.54 dl / g. The glass transition temperature of this product was 160 ° C. Further, the infrared absorption spectrum analysis of this polymer, the absorption by the carbonyl group in the position of 1750 cm ^-1, absorption by carbon-oxygen bond was observed at a position of 1250 cm ^-1. In addition, ¹ H-NMR (acetone d ₆ )
δ (ppm) was 2.1 (s 3H) and 6.8 to 8.0 (m 25H). From these facts, this polymer is recognized as a polycarbonate composed of the following repeating units.

Further, this polymer was molded into a bar flow molded product with a mini mat molding machine manufactured by Sumitomo Heavy Industries, Ltd., and its birefringence was measured. The average value was 70 nm, which is excellent in optical properties. I understand.

Example 2 As a dihydric phenol, 1-obtained in Reference Example 2 above
The same procedure as in Example 1 was carried out except that (4-methoxyphenyl) -1,1-bis (3-phenyl-4-hydroxyphenyl) ethane was used. The intrinsic viscosity [η] of the obtained polymer measured in the same manner as in Example 1 was 0.65 dl / g, the glass transition temperature was 164 ° C., ¹ H-NMR (acetone d ₆ ) δ (ppm) was
It was 2.2 (s 3H), 3.8 (s 3H), and 6.9 to 8.0 (m 20H). From these, it was confirmed that the polycarbonate was composed of the following repeating units.

[Effects of the Invention] The polycarbonate resin of the present invention is a novel polymer, and is excellent in the original properties of this resin such as heat resistance and transparency, and is also excellent in optical properties. It is useful as a material for electrical and electronic equipment, machinery, and especially optical equipment.

Claims (2)

(57) [Claims] 1. (In the formula, R ¹ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms,
R ² is an alkyl group having 1 to 5 carbon atoms or a phenyl group) and has an intrinsic viscosity of 0.
Polycarbonate resin with 3dl / g or more. 2. (In the formula, R ¹ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms,
R ² is an alkyl group having 1 to 5 carbon atoms or a phenyl group), and a carbonic acid ester forming compound is reacted with a dihydric phenol represented by (In the formula, R ¹ and R ² have the above-mentioned meanings), and the intrinsic viscosity is 0.
A method for producing a polycarbonate-based resin that is 3 dl / g or more.