KR101702040B1 - Manufacturing method of polycarbonate - Google Patents

Abstract

The present invention relates to a process for producing polycarbonate. Specifically, a method for producing a polycarbonate which is a terpolymer of EO / CHO / CO ₂ having excellent thermal stability is provided using a specific cobalt complex having a neutral single site as a catalyst.

Description

{Manufacturing method of polycarbonate}

The present invention relates to a process for producing polycarbonate.

Polycarbonate is a polymeric material useful for packaging materials or coating materials. The method of producing polycarbonate from an epoxy compound and carbon dioxide is highly environmentally friendly because it does not use phosgene, which is a toxic compound, and that it can obtain carbon dioxide in air. Many researchers have developed various types of catalysts to produce polycarbonate from epoxy compounds and carbon dioxide.

Significant progress has been made in the area of catalyst development since 2000. Typical examples are Salen Co compound or Salen Cr compound [H ₂ Salen = N , N ' -bis (3,5-dialkylsalicylidene) -1,2-cyclohexanediamine)] and [R ₄ N] Cl or PPNCl (bis (triphenylphoshine) iminium chloride) or a base such as an amine or a phosphine. For the binary catalyst system of the salen (Co) compound, the epoxide is coordinated and activated in a metal center having a Lewis acid group, which is activated with a carbonate derived from onium salt or a bulky amine base Mechanisms for attacking anions by nucleophiles have been proposed.

On the other hand, in Chinese Patent Laid-Open Publication No. 101412809, a method of synthesizing a salicene type Co complex catalyst containing one or two sterically large neutral organic base groups (TBD) and a method of copolymerizing the epoxide compound and carbon dioxide Discloses a method for producing polycarbonate. However, in the case of the above method, only the propylene oxide (PO) / CO ₂ copolymerization is mentioned.

As another method, there has been reported a method using a Sal complex type Co complex catalyst containing one quaternary ammonium salt (Macromolecules 2010, 43 (3), 1396-1402), the method comprising the PO / CO _2, CHO / CO producing a polycarbonate by copolymerization of _two or, CHO / PO, EO, BuO, poly three won through copolymerization of HO / CO ₂ Carbonate.

However, the conventional catalysts using EO / CHO / CO ₂ However, the above-mentioned methods have limitations in the catalytic activity and limit the increase of the thermal stability of the polymer because of easy back biting due to heating after polymerization.

It is an object of the present invention to provide a process for preparing a polycarbonate which is a terpolymer of EO / CHO / CO ₂ not only exhibiting excellent activity in copolymerization but also having excellent thermal stability, using a specific cobalt complex having a neutral single- .

According to one aspect of the present invention, there is provided a process for preparing a compound represented by formula

And a step of copolymerizing ethylene oxide, cyclohexene oxide and carbon dioxide.

[Chemical Formula 1]

(Wherein,

Q is an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, an aryl group having 6 to 30 carbon atoms, or an aryl group having 1 to 20 carbon atoms, which contains no or no halogen, nitrogen, oxygen, Lt; / RTI >

R ₁ to R ₃ are each independently or simultaneously hydrogen; Or an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an alkylaryl group having 7 to 20 carbon atoms, or an alkylaryl group having 7 to 20 carbon atoms, which contains no or at least one of halogen, nitrogen, oxygen, To 20 carbon atoms,

X is -NO ₃ or -OAc)

In the above formula (1), R ₁ to R ₃ each independently represent a t-butyl group.

In Formula 1, Q may be a 1,2-cyclohexylene group.

The polycarbonate may include an EO / CHO / CO ₂ terpolymer having a weight average molecular weight of 20,000 to 400,000.

The cyclohexene oxide may be used in a molar ratio of 1: 2,000 to 1: 10,000 relative to the catalyst. The ethylene oxide may be used in a molar ratio of 1: 10,000 to 1: 100,000 relative to the catalyst.

In the copolymerization step, carbon dioxide can be introduced at normal pressure and a pressure of 100 atm. The copolymerization may be carried out at a temperature of 20 ° C to 120 ° C for 1 hour to 24 hours.

The copolymerization may be carried out by further using at least one solvent selected from the group consisting of aliphatic hydrocarbons, aromatic hydrocarbons and halogenated hydrocarbons.

In addition, if necessary in the present invention, in the step of the copolymer (n-Bu) ₄ NY (where, Y = Cl, or OAc), [PPN] Cl, [PPN] Br and [PPN] from the group consisting of N ₃ The ammonium salt selected may additionally comprise as cocatalyst.

The present invention provides a terpolymer of EO / CHO / CO ₂ having excellent thermal stability by using a specific cobalt complex having a neutral single-site catalyst as a catalyst in the production of polycarbonate.

Hereinafter, the present invention will be described in more detail. The terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms and the inventor may appropriately define the concept of the term in order to best describe its invention It should be construed as meaning and concept consistent with the technical idea of the present invention.

According to an embodiment of the present invention, there is provided a process for producing a polycarbonate comprising copolymerizing ethylene oxide (EO), cyclohexene oxide (CHO) and carbon dioxide using a complex represented by the following formula (1) as a catalyst.

[Chemical Formula 1]

(Wherein,

Q is an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, an aryl group having 6 to 30 carbon atoms, or an aryl group having 1 to 20 carbon atoms, which contains no or no halogen, nitrogen, oxygen, Lt; / RTI >

R ₁ to R ₃ are each independently or simultaneously hydrogen; Or an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an alkylaryl group having 7 to 20 carbon atoms, or an alkylaryl group having 7 to 20 carbon atoms, which contains no or at least one of halogen, nitrogen, oxygen, To 20 carbon atoms,

X is -NO ₃ or -OAc)

Ethylene oxide (EO), ethylene oxide and cyclohexene oxide (CHO), which are highly reactive epoxy compounds, are activated by the catalyst of the present invention and react with carbon dioxide to be polymerized with polycarbonate.

The cobalt complex of Formula 1 used in the present invention is a neutral single-site catalyst. When used as a catalyst in the terpolymerization of EO / CHO / CO ₂ , the cobalt complex of Formula 1 exhibits high reactivity and selectivity to existing complexes, Increases stability. In addition, the complex of the present invention can exhibit excellent activity not only in EO but also in ternary copolymer with CHO.

In the complex of formula (1), X is preferably -NO ₃ or -OAc, more preferably -OAc.

In Formula 1, R ₁ to R ₃ may each independently be a t-butyl group.

In Formula 1, Q may be a 1,2-cyclohexylene group.

Accordingly, the complex of the present invention may have a structure of the following formula 1-1 according to a preferred embodiment.

[Formula 1-1]

(Wherein X is -NO ₃ or -OAc)

The complex of formula (1) of the present invention can be prepared by replacing halogen with an acetate group (-OAc) while X is substituted with a halogen such as -Cl or -I.

In the present invention, the CHO may be used as a copolymer to prevent unzipping, and may be used in an amount of 10 wt% or less based on the total amount used. According to the present invention, polycarbonate containing various contents of CHO is provided. Since the thermal stability is increased as the content of CHO is increased, it is more suitable for use as a packaging material or a coating material compared to conventional products.

Preferably, the cyclohexene oxide may be used in a molar ratio of 1: 2,000 to 1: 10,000, relative to the catalyst. If the ratio is less than 1: 2,000, the content of CHO is high and the polymerization of CHO / CO ₂ proceeds preferentially. If the ratio exceeds 1: 10,000 relative to the catalyst, the content of CHO is small, There is a problem that it is difficult to see the effect of improving the structure due to the copolymerization of CHO / CO ₂ .

The ethylene oxide may be used in a molar ratio of 1: 10,000 to 1: 100,000 relative to the catalyst. At this time, if the ratio is less than 1: 10,000 with respect to the catalyst, it is difficult to remove the catalyst residue from the produced PEC due to excessive amount of catalyst, easy back-burning after polymerization, and TOF is decreased per g of catalyst . If the ratio is more than 1: 100,000 as compared with the catalyst, there is a problem that the amount of the catalyst is insufficient to affect the efficiency of terpolymerization of EO and CHO due to interaction between cobalt metal active sites.

Ethylene oxide and cyclohexene oxide (CHO), which are alkylene oxides used in the present invention, may be used in polymerization using an organic solvent as a reaction medium. Examples of the solvent include aliphatic hydrocarbons such as pentane, octane, decane and cyclohexane, , Aromatic hydrocarbons such as toluene and xylene and the like, aromatic hydrocarbons such as chloromethane, methylene chloride, chloroform, carbon tetrachloride, 1,1-dichloroethane, 1,2-dichloroethane, ethyl chloride, trichloroethane, Halogenated hydrocarbons such as chloropropane, 1-chlorobutane, 2-chlorobutane, 1-chloro-2-methylpropane, chlorobenzene and bromobenzene may be used alone or in combination of two or more. More preferably, the bulk polymerization may be carried out using the epoxide compound itself as a solvent. The amount of the solvent to be used for the epoxy compound is not particularly limited and may be used in an amount well known in the art.

Further, if necessary, the in copolymer comprising: (n-Bu) ₄ NY (where, Y = Cl, or OAc), [PPN] Cl, [PPN] Br and [PPN] ammonium is selected from the group consisting of N ₃ The salt may further be included as a cocatalyst.

Further, in the process for producing a polycarbonate according to an embodiment of the present invention, the copolymerization may be carried out at a temperature of 20 ° C to 120 ° C for 1 to 24 hours.

That is, the polycarbonate polymerization method includes a batch polymerization method, a semi-batch polymerization method, or a continuous polymerization method. Here, in the case of using the batch or semi-batch polymerization method, the reaction time may be 1 to 24 hours, preferably 1.5 to 6 hours. The average residence time of the catalyst in the case of using the continuous polymerization method can also be set to 1 to 24 hours.

Further, the pressure of the carbon dioxide in the polycarbonate polymerization may be 100 atm at normal pressure, preferably 2 to 50 atm. In the copolymerization step, the polymerization temperature may be from 20 캜 to 120 캜, preferably from 50 캜 to 90 캜.

The polycarbonate produced by the method of the present invention may have a number average molecular weight of 10,000 to 300,000. The polycarbonate may also be a terpolymer of EO / CHO / CO ₂ (i.e., poly (cyclohexene carbonate)). Preferably, the polycarbonate may comprise an EO / CHO / CO ₂ terpolymer having a weight average molecular weight of 20,000 to 400,000.

According to the present invention, the TOF is 300 to 1,500 (mol / mol-cat.hr), and the number of molecules reacted per unit active point per unit time is large, so that sufficient activity for polycarbonate production can be exhibited.

Hereinafter, preferred embodiments of the present invention will be described in detail. It should be understood, however, that these examples are for illustrative purpose only and are not to be construed as limiting the scope of the present invention

Example  1 to 2

As a catalyst, EO / CHO / CO ₂ polymerization proceeded to prepare a polycarbonate as a terpolymer. The polymerization conditions and results are shown in Table 1 below.

[Formula 1-1]

(In the structure of Formula 1-1, X is -NO ₃ )

That is, the cobalt complex compound of Formula 1-1, ethylene oxide and cyclohexene oxide were added to a 30 mL bomb reactor, and the reactor was assembled. Then, the reactor was immersed in an oil bath whose temperature was adjusted in advance, and stirred for about 15 minutes so that the reactor temperature was in equilibrium with the bath temperature, and a carbon dioxide gas pressure of 20 bar was applied. At this time, the amounts of ethylene oxide and cyclohexene oxide used were changed as shown in Table 1.

As the reaction proceeded, it was observed that the carbon dioxide pressure dropped. After the pressure dropped to about 3 bar, the carbon dioxide gas was withdrawn to terminate the reaction. The obtained viscous liquid was dropped into a methanol solvent to obtain a white solid. After stirring in methanol for about 12 hours, a solid was obtained and the polymer was dried in a vacuum of 60 < 0 > C. Through these procedures, the polyethylene carbonate of each of Examples 1 and 2 was prepared.

¹ H NHR data showed that a peak due to CHO / CO ₂ copolymerization was found near d = 4.664 and d = 2.15 as compared with the sample polymerized without adding cyclohexene oxide (CHO) .

Example  3 to 4

Polyethylene carbonate was prepared in the same manner as in Example 1, except that the substituent in the complex of Formula 1-1 was -OAc. The polymerization conditions and results are shown in Table 1 below.

Example 1 Example 2 Example 3 Example 4 The catalyst (Formula 1-1) X = NO ₃ X = NO ₃ X = OAc X = OAc The amount of catalyst (mg) 3.1 3.2 2.81 2.95 The amount of catalyst (μmol) 3.9 4.1 3.90 4.10 EO (g) 12.80 14.70 12.80 14.70 EO / cat. 73658 63094 73658 63094 CHO (g) 1.18 2.36 1.18 2.36 CHO (mmol) 12 24 12 24 Time (hr) 4 4 4 4 CHO / Cat. 3048 5904 3048 5904 CHO / EO (%) 4.14 9.36 4.41 9.36 CO ₂ (bar) 20 20 20 20 Temperature (℃) 70 70 70 70 Yield (g) 1.5 0.5 2.9 1.1 TOF (mol / mol-cat.hr) 1080 465 2088 1023 EO conversion rate (%) 6 2 11.6 4.4 Yield (g / g-cat.) 484 156 1032 373

Note) TOF: Turnover frequency, that is, the number of molecules reacted per unit active point per unit time, which is calculated using the turnover number (TON), ie, the number of molecules reacted per unit active point.

From the above Table 1, it was confirmed that the catalyst of the present invention had excellent activity using a catalyst having neutral single sites, and an EO / CHO / CO ₂ terpolymer having a large molecular weight could be produced. Also, TOF decreased with increasing CHO content, and it was confirmed that conversion of CHO can be controlled by adjusting the amount of CHO.

While the present invention has been particularly shown and described with reference to specific embodiments thereof, those skilled in the art will appreciate that such specific embodiments are merely preferred embodiments and that the scope of the present invention is not limited thereby. something to do. It is therefore intended that the scope of the invention be defined by the claims appended hereto and their equivalents.

Claims (10)

Using a complex represented by the following formula (1) as a catalyst,
Comprising copolymerizing ethylene oxide, cyclohexene oxide and carbon dioxide,
The cyclohexene oxide was used in a molar ratio of 1: 2,000 to 1: 10,000 relative to the catalyst,
The ethylene oxide is used in a molar ratio of 1: 63,094 to 1: 100,000 relative to the catalyst,
A process for producing a polycarbonate comprising a terpolymer of ethylene oxide, cyclohexene oxide and CO ₂ having a weight average molecular weight of 20,000 to 400,000.
[Chemical Formula 1]

(Wherein,
Q is an alkylene group having 1 to 20 carbon atoms, a cycloalkylene group having 3 to 20 carbon atoms, an arylene group having 6 to 30 carbon atoms, or an alkylene group having 1 to 20 carbon atoms, which is free of halogen, nitrogen, oxygen, silicon, 20 < / RTI > dioxy radical,
R ₁ to R ₃ are each independently or simultaneously hydrogen; Or an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an alkylaryl group having 7 to 20 carbon atoms, or an alkylaryl group having 7 to 20 carbon atoms, which contains no or at least one of halogen, nitrogen, oxygen, To 20 carbon atoms,
X is -NO ₃ or -OAc)
The process for producing a polycarbonate according to claim 1, wherein R ₁ to R ₃ in the general formula (1) are independently t-butyl groups.
The process for producing a polycarbonate according to claim 1, wherein Q in the formula (1) is 1,2-cyclohexylene.
delete delete delete The method for producing polycarbonate according to claim 1, wherein the carbon dioxide in the step of copolymerizing is introduced at a pressure of 100 atm.
The process for producing a polycarbonate according to claim 1, wherein the copolymerization is carried out at a temperature of 20 ° C to 120 ° C for 1 hour to 24 hours.
The process for producing a polycarbonate according to claim 1, wherein the copolymerization is carried out by further using at least one solvent selected from the group consisting of aliphatic hydrocarbons, aromatic hydrocarbons and halogenated hydrocarbons.
The method of claim 1, wherein in the copolymerizing step
(n-Bu) ₄ NY (where, Y = Cl, or OAc), [PPN] Cl, [PPN] Br and [PPN] polycarbonate containing the ammonium salt is selected from the group consisting of N ₃ in addition to the co-catalyst ≪ / RTI >