KR20110078214A - Polycarbonate resin having excellent heat resistance, hydrolysis resistance, color, and electrostatic property and method of preparing the same - Google Patents

Abstract

PURPOSE: A polycarbonate resin is provided to improve thermal stability and color stability at high temperature as well as ensuring excellent hydrolysis resistance and to enable the application to molding products with much moisture contact. CONSTITUTION: A polycarbonate resin in which the concentration of a terminal hydroxyl group is 0.01-15 % is prepared by polymerizing a monomer mixture including an aromatic dihydroxy compound and diarylcarbonate. The monomer mixture does not include an end terminator or includes 0-0.001 weight% of the end terminator. The diarylcarbonate is included in the range of 1.18-1.32 mole per 1 mole of the aromatic dihydroxy compound.

Description

Polycarbonate Resin Having Excellent Heat Resistance, Hydrolysis resistance, Color, and Electrostatic Property and Method of Preparing the Same}

The present invention relates to a polycarbonate resin excellent in heat resistance, hydrolysis resistance, color tone, and electrostatic properties, and a method for producing the same.

More specifically, the present invention relates to a polycarbonate resin having improved heat resistance, hydrolysis resistance, color tone, and electrostatic properties by adjusting the concentration of terminal hydroxyl groups in all terminal groups without a terminal terminator to 0.01 to 15%, and a method of manufacturing the same. .

Polycarbonate is excellent in mechanical properties such as impact resistance, and excellent in self-extinguishing, dimensional stability, heat resistance and transparency, the application range of electric and electronic product exterior materials, automotive parts, etc. are increasing day by day.

In general, the polycarbonate is prepared by interfacial polymerization of bivalent phenol salts such as bisphenol A and phosgene in a liquid phase, and diaryl carbonates such as diphenyl carbonate in the above state. There is a method of manufacturing by the exchange method.

The method of preparing polycarbonate by transesterification can eliminate the use of highly toxic substances such as phosgene, do not use organic solvents such as methylene chloride, and do not require cleaning process using a large amount of water. It is an environmentally friendly manufacturing process and the future is a bright manufacturing process.

However, unlike the interfacial reaction which terminates the reaction through the use of monovalent phenolic compounds, the transesterification reaction does not use a reaction terminator. Due to this process difference, the polycarbonate resin produced by the transesterification reaction has a higher terminal hydroxyl group composition than the polycarbonate resin produced by the interfacial reaction.

Polycarbonate is excellent in mechanical properties such as impact resistance, and excellent in self-extinguishing, dimensional stability, heat resistance and transparency, the application range of electric and electronic product exterior materials, automotive parts, etc. are increasing day by day.

In general, the polycarbonate is prepared by interfacial polymerization of bivalent phenol salts such as bisphenol A and phosgene in a liquid phase, and diaryl carbonates such as diphenyl carbonate in the above state. There is a method of manufacturing by the exchange method.

The method of preparing polycarbonate by transesterification can eliminate the use of highly toxic substances such as phosgene, do not use organic solvents such as methylene chloride, and do not require cleaning process using a large amount of water. It is an environmentally friendly manufacturing process and the future is a bright manufacturing process.

However, unlike the interfacial reaction which terminates the reaction through the use of monovalent phenolic compounds, the transesterification reaction does not use a reaction terminator. Due to this process difference, the polycarbonate resin produced by the transesterification reaction has a higher terminal hydroxyl group composition than the polycarbonate resin produced by the interfacial reaction.

In order to achieve the above technical problem, the present invention is prepared by polymerizing a monomer mixture comprising an aromatic dihydroxy compound and a diaryl carbonate, characterized in that the monomer mixture does not contain an end-stopping agent, out of the entire terminal group It provides a polycarbonate resin having a concentration of terminal hydroxyl groups of 0.01 to 15%.

In order to achieve the above another technical problem, the present invention is prepared by polymerizing a monomer mixture comprising an aromatic dihydroxy compound and a diaryl carbonate, the monomer mixture is 0 to 0.001% by weight of a terminating agent It is characterized in that it comprises a polycarbonate resin having a concentration of 0.01 to 15% of the terminal hydroxyl group in the total terminal group.

In one embodiment of the invention, the terminating agent is at least one dialkyl selected from the group consisting of dibutyl carbonate, dipentyl carbonate, butyl pentyl carbonate, dihexyl carbonate, dicyclohexyl carbonate, diheptyl carbonate, dioctyl carbonate It may be a carbonate or an aromatic carbonate derivative compound represented by the following formula (1).

[Formula 1]

(Wherein R ₁ is hydrogen, t-butyl group, p-cumyl group, R ₂ is t-butyl group, p-cumyl group).

In another embodiment of the present invention, the diaryl carbonate is included in the range of 1.18 to 1.32 moles per mole of the aromatic dihydroxy compound.

In another embodiment of the present invention, the aromatic dihydroxy compound is characterized by the following formula (2).

(2)

Wherein A represents a single bond, C ₁ -C ₅ alkylene, C ₁ -C ₅ alkylidene, C ₅ -C ₆ cycloalkylidene, -S- or -SO _2- .

In another embodiment of the present invention, the diaryl carbonate is diphenyl carbonate, ditoryl carbonate, bis (chlorophenyl) carbonate, m-cresyl carbonate, dinaphthyl carbonate, bis (diphenyl) carbonate, diethyl At least one selected from the group consisting of carbonate, dimethyl carbonate, dibutyl carbonate, dicyclohexyl carbonate.

In another embodiment of the present invention, the polycarbonate resin is dried for 4 hours at 120 ℃ after injection at a molding temperature of 290 ℃, mold temperature 70 ℃ conditions in a 10 OZ injection machine to produce a specimen of 3mm thickness 90 ℃, 95 Molecular weight retention after retention for 7 days in a constant temperature and humidity chamber of% relative humidity is 96% or more.

In another embodiment of the present invention, the polycarbonate resin is a specimen temperature of 340 ℃, a mold temperature of 70 ℃ and a cooling time of 300 seconds to prepare a specimen of 3mm thickness, and the specimen is kept at 340 ℃, 5 minutes The yellowness (ΔYI) before and after the retention measured using a color difference meter (ND-1001 DP) manufactured by Nippon Denshoku Kogyo Co., Ltd. after the retention was 1.5 or less.

In order to achieve the above another technical problem, the present invention provides a method for producing a polycarbonate resin having a concentration of 0.01 to 15% of the terminal hydroxyl group in the entire terminal group without using an end stopper.

In another embodiment of the present invention, the method for producing the polycarbonate resin is characterized in that the polymerization by controlling the diaryl carbonate per mole of aromatic dihydroxy compound in the range of 1.18 to 1.32 moles.

In another embodiment of the present invention, the aromatic dihydroxy compound used in the method for producing the polycarbonate resin is represented by the formula (2).

In another embodiment of the present invention, the diaryl carbonate used in the method for preparing the polycarbonate resin is diphenyl carbonate, ditoryl carbonate, bis (chlorophenyl) carbonate, m-cresyl carbonate, dinaphthyl carbonate, At least one selected from the group consisting of bis (diphenyl) carbonate, diethyl carbonate, dimethyl carbonate, dibutyl carbonate, dicyclohexyl carbonate.

In order to achieve the above another technical problem, the present invention provides a molded article prepared from the polycarbonate resin.

The present invention does not use a terminal terminator, and adjusts the diphenyl carbonate / bisphenol A molar ratio to easily reduce the concentration of the hydroxyl group by applying the existing equipment without modification or change of the reaction process, as well as high temperature during the molding process In addition to improving thermal stability, color stability, and the like, and improving hydrolysis resistance, the present invention provides a polycarbonate resin that can be applied to outdoor structures and moldings having a lot of moisture contact, and a method of manufacturing the same.

Hereinafter, the present invention will be described in more detail.

The present invention is prepared by polymerizing a monomer mixture comprising an aromatic dihydroxy compound and a diaryl carbonate, wherein the monomer mixture does not contain an end-stopping agent. Provides 15% polycarbonate resin.

In another aspect, the present invention is prepared by polymerizing a monomer mixture comprising an aromatic dihydroxy compound and a diaryl carbonate, wherein the monomer mixture comprises 0 to 0.001% by weight of an end stopper, the terminal of the total terminal group It provides a polycarbonate resin having a concentration of hydroxyl groups of 0.01 to 15%.

In an embodiment, the polycarbonate resin is prepared by transesterifying the dihydroxy compound and the diaryl carbonate in the presence of a catalyst consisting of alkali, alkaline earth metal or a mixture thereof.

(A) Aromatic Dihydroxy Compound

The aromatic dihydroxy compound of the present invention may be represented by the following formula (2).

[Formula 2]

Wherein A represents a single bond, C ₁ -C ₅ alkylene, C ₁ -C ₅ alkylidene, C ₅ -C ₆ cycloalkylidene, -S- or -SO _2-

Specific examples of the dihydroxy compound of the formula (2) include 4,4'-dihydroxydiphenyl, 2,2-bis- (4-hydroxyphenyl) -propane, 2,4-bis- (4-hydroxyphenyl ) -2-methylbutane, 1,1-bis- (4-hydroxyphenyl) -cyclohexane, 2,2-bis- (3-chloro-4-hydroxyphenyl) -propane, 2,2-bis- (3,5-dichloro-4-hydroxyphenyl) -propane etc. are mentioned. Among them, 2,2-bis- (4-hydroxyphenyl) -propane, 2,2-bis- (3,5-dichloro-4-hydroxyphenyl) -propane, 1,1-bis- (4- Hydroxyphenyl) -cyclohexane and the like are preferred, and 2,2-bis- (4-hydroxyphenyl) -propane, also referred to as bisphenol-A, is most preferred.

(B) diaryl carbonate

Examples of the diaryl carbonate include diphenyl carbonate, ditoryl carbonate, bis (chlorophenyl) carbonate, m-cresyl carbonate, dinaphthyl carbonate, bis (diphenyl) carbonate, diethyl carbonate, dimethyl carbonate, dibutyl carbonate, Dicyclohexyl carbonate etc. are mentioned, It is not necessarily limited to this. These may be used alone or in combination of two or more, preferably diphenyl carbonate.

In an embodiment of the present invention, the diaryl carbonate is used in the range of 1.18 to 1.32 moles per mole of the aromatic dihydroxy compound.

Existing polycarbonate resin has a terminal hydroxyl group concentration of 20 to 30%, resulting in poor thermal stability. When blending a polycarbonate resin having a high terminal hydroxyl group concentration, the terminal hydroxyl group is extruded at a high temperature and high pressure. Reacts with other additives to cause deterioration of physical properties and discoloration, and generates static electricity by friction with the mold during injection. Until now, it was essential to cap terminal hydroxyl groups using terminal terminators in order to control the concentration of terminal hydroxyl groups in a low range. However, the present inventors can lower the terminal hydroxy concentration by adjusting the molar ratio of the diaryl carbonate and the aromatic dihydroxy compound without using a terminal terminator, and as a result, polycarbonate having excellent thermal stability, color tone, and electrostatic properties It was found that a resin could be prepared.

When the molar ratio of the diaryl carbonate and the aromatic dihydroxy compound of the present invention exceeds 1.32, the polymerization chain reaction is terminated prematurely, the molecular weight of the chain is not sufficiently secured, and as a result, the impact strength may be lowered. On the other hand, when the molar ratio of the diaryl carbonate and the aromatic dihydroxy compound is less than 1.18, the concentration of the terminal hydroxy group is increased, resulting in a bad effect on the physical properties. That is, the molar ratio of the diaryl carbonate / aromatic dihydroxy compound for adjusting the concentration of the terminal hydroxyl group in the total terminal group in the range of 0 to 15% is from 1.18 to 1.32.

(C) end terminator

End stoppers, also called chain stoppers or capping agents, are compounds added to control the molecular weight and provide a good processability polymer.

The carbonate resin having a concentration of 0.01 to 15% of the terminal hydroxyl group in the entire terminal group of the present invention is prepared by polymerizing a monomer mixture containing no terminal terminator, or containing a small amount of terminal terminator at 0 to 0.001% by weight. It can be prepared by polymerizing the monomer mixture.

In an embodiment, the terminal stopper is at least one dialkyl carbonate selected from dibutyl carbonate, dipentyl carbonate, butylpentyl carbonate, dihexyl carbonate, dicyclohexyl carbonate, diheptyl carbonate, dioctyl carbonate, or the like The aromatic carbonate derivative compound may be, but is not limited thereto.

[Formula 1]

(Wherein R ₁ is hydrogen, t-butyl group, p-cumyl group, R ₂ is t-butyl group, p-cumyl group).

(D) catalysts and additives

In the present invention, it may be carried out in the presence of a catalyst to promote the transesterification reaction. Examples of the catalyst may include hydroxides, oxides, amide compounds, alkoxy compounds, transition metal oxides, nitrogen-containing basic compounds, phosphorus-containing basic compounds, and the like of alkali metals and alkaline earth metals, but are not limited thereto. These may be used alone or in combination of two or more thereof. In the present invention, each or a combined catalyst can be added to the reaction mixture in the form of a hydrate.

The polycarbonate resin according to the present invention may further include an additive. The additives include flame retardants, antibacterial agents, mold release agents, heat stabilizers, antioxidants, light stabilizers, compatibilizers, dyes, inorganic additives, fillers, plasticizers, impact modifiers, admixtures, colorants, stabilizers, lubricants, antistatic agents, pigments, weathering agents, ultraviolet rays Blocking agents and mixtures thereof.

In an embodiment of the present invention, the transesterification reaction may proceed under reduced pressure at 160 to 300 ℃, preferably 200 to 300 ℃, more preferably 220 to 260 ℃. It is preferable in the reaction rate and side reaction reduction in the above temperature range.

In addition, it is preferable that the transesterification reaction proceeds for at least 10 minutes or more, preferably 15 minutes to 24 hours, more preferably 15 minutes to 3 hours under reduced pressure of 1 torr or less in terms of reaction rate and side reactions.

After the polymerization is completed, the polymer is discharged into a water bath and cooled, and then a polymer may be obtained through a drying process. The polymer thus obtained can be pelletized through an extrusion process, and an appropriate additive can be added to this process to obtain a resin composition having improved stability.

The polycarbonate resin of the present invention prepared by the above method has a final terminal hydroxyl concentration of the entire terminal group without including a terminal terminator.

By controlling the molar ratio of the diaryl carbonate and the aromatic dihydroxy compound, the present invention can dramatically reduce the terminal hydroxyl group of the polycarbonate without any modification or addition of existing equipment. Therefore, when the polycarbonate of the present invention is applied, thermal stability and color tone stability can be significantly increased, and generation of static electricity during injection can be reduced.

 In one embodiment, the polycarbonate resin is dried at 120 ℃ for 4 hours and then injected into a mold temperature of 290 ℃, mold temperature 70 ℃ conditions in a 10 OZ injection machine to produce a specimen of 3mm thickness of 90 ℃, 95% relative humidity The molecular weight retention rate after staying for 7 days in a constant temperature and humidity chamber is 96% or more.

In another embodiment, the polycarbonate resin is a mold temperature of 340 ℃, a mold temperature of 70 ℃ conditions and a cooling time of 300 seconds to prepare a specimen of 3mm thickness, the specimen was kept at 340 ℃, 5 minutes after Nippon Denshoku The yellowness (ΔYI) before and after the retention measured using a color difference meter (ND-1001 DP) manufactured by Kogyo Co., Ltd. is 1.5 or less.

The polycarbonate resin may be used in molded products in fields requiring durability, heat resistance, and transparency, such as automobiles, mechanical parts, electrical and electronic parts, office equipment such as computers, and miscellaneous goods. In particular, the present invention can be suitably applied to housings of electrical and electronic products such as televisions, computers, printers, washing machines, cassette players, audio, mobile phones, game machines, toys, and the like. As the molding method, a conventional method may be applied, and for example, extrusion molding, injection molding, vacuum molding, casting molding, extrusion molding, blow molding, calendar molding, or the like may be applied. These are well known by those skilled in the art to which the present invention belongs.

The invention can be better understood by the following examples, which are intended for purposes of illustration of the invention and are not intended to be limited or limited by the appended claims.

Example

Example 1

180.0 Kg (788.5 mol) of 2,2-bis (4-hydroxyphenyl) propane (bisphenol A), 202.7 Kg (946.2 mol) of diphenylcarbonate, and 100 ppb of KOH (relative to 1 Kg of BPA) were sequentially added to the reactor, Nitrogen was used to remove oxygen in the reactor. The temperature of the reactor was raised to 160 degrees to melt the raw material, and the temperature was raised to 190 degrees and maintained for 6 hours. The reactants maintained for 6 hours were continuously supplied to the first reactor, and the temperature was raised to 220 degrees, followed by continuous supply to the second reactor while maintaining the pressure at 70 Torr for 1 hour. The second reactor temperature was 260 degrees and continuously fed to the third reactor while maintaining at 20 torr for 1 hour. The temperature of the third reactor was raised to 265 ° C. and the pressure was lowered to 5 torr and continuously fed to the fourth reactor while being maintained for 1 hour. The fourth reactor temperature was 265 degrees and the pressure was lowered to 0.5 torr and maintained for 1 hour. Phenolic, a byproduct generated during the reaction, was extracted outside the reactor by evaporation.

The resulting polycarbonate resin was prepared into pellets using an extruder and a pelletizer. The molecular weight of the prepared polycarbonate was measured using GPC-TDA (triple detector gel chromatography) and the terminal hydroxyl group concentration was measured by H-NMR (500MHz). The prepared polycarbonate pellets were dried at 120 ° C. for 4 hours, and then injected at a mold temperature of 290 ° C. and a mold temperature of 70 ° C. in a 10 OZ injection machine to prepare a specimen having a thickness of 3 mm. Molecular weight retention rate (%) was measured after staying for a day, and high temperature thermal stability evaluation was performed using an injection machine (DHC-180MC) manufactured by Dongshin Hydraulic Co., Ltd. at a molding temperature of 340 ° C and a mold temperature of 70 ° C. The yellowness (ΔYI) before and after the retention was measured using a colorimeter (ND-1001 DP) manufactured by Nippon Denshoku Kogyo Co., Ltd. for a 300 mm thick specimen. The degree of discoloration increases according to the number of moldings of the molded article. When the color (YI) difference of three consecutive molded articles is less than 0.3, discoloration is regarded as stabilized, and yellowness when discoloring maintains a stable value is determined. It is measured. Izod impact is measured at 23 ° C. by the ASTM D7265 method.

Example 2

Diphenyl carbonate was carried out in the same manner as in Example 1, except that 205.2 Kg (958.0 mol) was used.

Example 3

The same procedure as in Example 1 was conducted except that 207.8 Kg (969.8 mol) of diphenyl carbonate was used.

Comparative Example 1

Diphenyl carbonate was carried out in the same manner as in Example 1, except that 194.2 Kg (906.7 mol) was used.

Comparative Example 2

Diphenyl carbonate was carried out in the same manner as in Example 1, except that 199.3 Kg (930.4 mol) was used.

Comparative Example 3

Diphenyl carbonate was carried out in the same manner as in Example 1, except that 223.0 Kg (1040.8 mol) was used.

Example Comparative example One 2 3 One 2 3 Diphenyl carbonate /
Bisphenol A molar ratio 1.200 1.215 1.230 1.150 1.160 1.340 Weight average molecular weight 22300 21800 21900 22100 22000 8900 Terminal hydroxyl groups
density(%) 9.8 6.2 4.3 31.3 21.5 10.2 Izod Impact
(notched 1/8 ") 72.9 72.2 72.5 72.4 72.7 57.2 △ YI
(340 ° C, 5 min stay) 1.3 0.5 0.2 2.4 2.0 1.5 Molecular weight retention rate (%)
(90 ° C, 95%, 7 days) 97.6 99.2 99.7 94.4 95.2 97.4

When the polycarbonate is produced at a diphenyl carbonate / bisphenol A molar ratio of 1.200 or more as in the embodiment of the present invention, the terminal hydroxy concentration is 15% or less, and it can be confirmed that the thermal stability, color stability, and hydrolysis resistance are all excellent. . However, as in Comparative Example 3, at a molar ratio of 1.32, the number average molecular weight is less than 10,000, it can be confirmed that the impact falls. Thus, it can be seen that the diphenyl carbonate / bisphenol A molar ratio is from 1.200 to 1.300 to reduce terminal hydroxy concentration.

Claims (13)

It is prepared by polymerizing a monomer mixture comprising an aromatic dihydroxy compound and a diaryl carbonate, wherein the monomer mixture does not contain an end terminator, wherein the concentration of the terminal hydroxyl group in the total terminal groups is 0.01 to 15%. Polycarbonate resin. It is prepared by polymerizing a monomer mixture comprising an aromatic dihydroxy compound and a diaryl carbonate, wherein the monomer mixture comprises a terminal terminator at 0 to 0.001% by weight. Polycarbonate resin is 0.01 to 15%. The method of claim 2, wherein the terminal stopper is at least one dialkyl carbonate selected from the group consisting of dibutyl carbonate, dipentyl carbonate, butyl pentyl carbonate, dihexyl carbonate, dicyclohexyl carbonate, diheptyl carbonate, dioctyl carbonate or Polycarbonate resin characterized in that the aromatic carbonate derivative compound represented by the formula (1): [Formula 1]

(Wherein R ₁ is hydrogen, t-butyl group, p-cumyl group, R ₂ is t-butyl group, p-cumyl group). The polycarbonate resin according to claim 1 or 2, wherein the diaryl carbonate is included in the range of 1.18 to 1.32 moles per mole of the aromatic dihydroxy compound. The polycarbonate resin according to claim 1 or 2, wherein the aromatic dihydroxy compound is represented by the following Chemical Formula 2: [Formula 2]

Wherein A represents a single bond, C ₁ -C ₅ alkylene, C ₁ -C ₅ alkylidene, C ₅ -C ₆ cycloalkylidene, -S- or -SO _2- . According to claim 1 or 2, wherein the diaryl carbonate is diphenyl carbonate, ditoryl carbonate, bis (chlorophenyl) carbonate, m-cresyl carbonate, dinaphthyl carbonate, bis (diphenyl) carbonate, di Polycarbonate resin, characterized in that at least one selected from the group consisting of ethyl carbonate, dimethyl carbonate, dibutyl carbonate, dicyclohexyl carbonate. The method according to claim 1 or 2, wherein the polycarbonate resin is dried at 120 ° C. for 4 hours and then injected into a mold temperature of 290 ° C. and a mold temperature of 70 ° C. in a 10 OZ injection machine to prepare a specimen having a thickness of 3 mm, and then 90 ° C., A polycarbonate resin having a molecular weight retention rate of 96% or more after 7 days in a constant temperature and humidity chamber of 95% relative humidity. According to claim 1 or 2, wherein the polycarbonate resin is a mold temperature of 340 ℃, a mold temperature of 70 ℃ conditions and a cooling time of 300 seconds to prepare a specimen of 3mm thickness, the specimen at 340 ℃, 5 The polycarbonate resin, characterized in that the yellowness (ΔYI) before and after the retention measured using a color difference meter (ND-1001 DP) manufactured by Nippon Denshoku Kogyo Co., Ltd. after retention for 1.5 minutes is 1.5 or less. A method for producing a polycarbonate resin in which the concentration of terminal hydroxyl groups in all terminal groups is 0.01 to 15% without using an end terminator. The method of claim 9, wherein the diaryl carbonate per mole of aromatic dihydroxy compound is controlled to be polymerized in the range of 1.18 to 1.32 moles to produce a polycarbonate resin. The method of claim 10, wherein the aromatic dihydroxy compound is represented by the following Chemical Formula 1. (2)

Wherein A represents a single bond, C ₁ -C ₅ alkylene, C ₁ -C ₅ alkylidene, C ₅ -C ₆ cycloalkylidene, -S- or -SO _2- . The method of claim 10, wherein the diaryl carbonate is diphenyl carbonate, ditoryl carbonate, bis (chlorophenyl) carbonate, m-cresyl carbonate, dinaphthyl carbonate, bis (diphenyl) carbonate, diethyl carbonate, dimethyl Method for producing a polycarbonate resin, characterized in that at least one selected from the group consisting of carbonate, dibutyl carbonate, dicyclohexyl carbonate. A molded article prepared from the polycarbonate resin of claim 1.