KR20080016198A - Process for the preparation of polycarbonates from epoxides and carbon dioxide using microwave - Google Patents

Abstract

A method for preparing a polycarbonate is provided to obtain a high production yield in a short time and to increase polymerization velocity by the copolymerization using microwave. A method for preparing a polycarbonate comprises the step of copolymerizing an epoxy compound and carbon dioxide in the presence of a catalyst by using microwave to prepare a polycarbonate represented by the formula 1, wherein R is CH3, C2H5, C4H9, C6H13, CH2CH-Ph, or -CH2-O-Ph; and m and n are a number of 2-100. Preferably the catalyst is the zinc cobalt cyanide prepared from K3[Co(CN)6] and a halogenated zinc; the pressure of carbon dioxide is 10-200 psi; and the copolymerization using microwave is carried out for 1-60 min.

Description

Process for the preparation of polycarbonates from epoxides and carbon dioxide using microwave}

The present invention relates to an epoxy compound using microwave and a method for producing polycarbonate from carbon dioxide. In the manufacturing method, a metal cyanide is used as a catalyst, and the present invention relates to a method for producing a polycarbonate, wherein a high yield is obtained in a short time by copolymerizing a microwave having a frequency of 2.45 GHz.

Polycarbonate resin is a commercialized thermoplastic resin and is a polycarbonate ester compound of bisphenol A. Transparent and excellent mechanical properties, especially balanced impact, heat resistance, cold resistance and electrical properties, and non-toxic and self-extinguishing engineering plastics for automotive bumpers, packaging materials, switches, hair dryers, fan parts, etc. It is used for mechanical parts such as electric parts, various fans, helmets and fire extinguisher covers.

The method for producing a polycarbonate resin includes an interfacial polymerization method (solvent method) and a transesterification method (dissolution method), and the conventional method mainly depends on the interfacial polymerization method (solvent method). In the case of the interfacial polymerization method (solvent method), polycarbonate resin is prepared by polymerizing at the interface between the aqueous solution and the organic solvent by vigorously mixing bisphenol A in an aqueous state substituted with sodium and phosgene contained in a chlorine organic solvent as raw materials. do. Therefore, phosgene, the raw material used above, has very strong toxicity, and chlorine-based organic solution is a volatile pollutant, which is the main cause of working environment and environmental pollution. Therefore, water or drainage after use is treated by activated sludge and adsorption by activated carbon. And ozone treatment to decompose, remove and discharge bisphenol A. In addition, in order to remove the salts and reaction residues remaining in the polycarbonate resin thus prepared, there was a problem that the washing and drying using a large amount of water

In the case of the above-described interfacial polymerization method (solvent method), although there are disadvantages in that the reaction time is long despite the use of various types of catalysts, an effort to improve the situation is required. Microwave is known to dramatically increase the speed of organic and inorganic synthesis reactions, the patent is increasing significantly. KY Choi et al .: US Pat. No. 6,525,169, Republic of Korea Patent Publication No. 10-0364496 is a polycarbonate resin that performs a solid phase polymerization by crystallizing a prepolymer polymerized from an aromatic dihydroxy compound and a diaryl carbonate Microwave was applied to the preparation of the high molecular weight polycarbonate manufacturing technology was developed in a short time.

On the other hand, as a countermeasure against global warming-causing substances, such as the conclusion of the Kyoto Protocol, we have secured our own process technology for industrial resources using carbon dioxide, and at the same time reduced the environmental pollution generated from existing chemical processes. It is time to actively pursue research to replace environmentally friendly processes.

From this point of view, the development of a chemical process that can utilize carbon dioxide is being developed in various ways by other advanced companies, and as part of this, carbon dioxide is used as a reaction raw material, and the existing phosgene process is environmentally friendly. Multifaceted efforts are underway to transition to non-phosgene carbon dioxide processes.

Therefore, the present invention is a new polycarbonate that can easily control the temperature in the reactor and obtain a high yield in a short time in the method for producing a polycarbonate by copolymerizing the epoxide compound and carbon dioxide in order to solve the above problems Manufacturing method is required.

The present inventors have made efforts to solve the conventional problems, using a metal cyanide as a catalyst in the process of producing a polycarbonate by copolymerizing with an epoxy compound using carbon dioxide, a global warming inducing substance, and applying microwaves, It is an object of the present invention to provide a method for producing a polycarbonate, wherein the polycarbonate can be obtained.

Therefore, another object of the present invention is to provide a method for producing polycarbonate, characterized in that the copolymerization speed is fast and the process is simple and eco-friendly. have.

Hereinafter, a method for producing polycarbonate directly from an epoxy compound and carbon dioxide using microwaves according to the present invention will be described in detail. In order to achieve the above technical problem, the present invention provides a polycarbonate having a structure of Formula 1 below.

Formula 1.

R in Formula 1 is as follows.

And the range of the repeating unit m, n of the two monomers constituting the resulting polycarbonate copolymer was able to produce a copolymer product in the range of about 2 to 100, respectively.

The method for preparing the polycarbonate copolymer of Chemical Formula 1 is shown in Scheme 1 below.

Scheme 1.

R in Scheme 1 is as follows.

And the range of the repeating unit m, n of the two monomers constituting the resulting polycarbonate copolymer was able to produce a copolymer product in the range of about 2 to 100, respectively.

As shown in Scheme 1, carbon dioxide is added to the epoxy ring of the epoxy compound by copolymerizing the epoxide with carbon dioxide in the presence of a catalyst, thereby preparing a polycarbonate that is a copolymer containing a carbonate group and an ether group.

The catalyst used in the reaction is a double metal cyanide, and zinc cobalt cyanide prepared from K [Co (CN) ₆ ] and zinc halide ZnX ₂ (X is Cl, Br, I, F). Is preferred. The amount of such a catalyst is not particularly limited as long as it is sufficient to act as a catalyst, and it is preferable to use a molar ratio of 1/30 to 1/100 with respect to the epoxy compound.

When the amount of the catalyst used is less than 1/100 of the molar ratio of the epoxy compound, the reaction between the epoxy compound and carbon dioxide is not sufficient, and there is a possibility that the unreacted epoxy compound remains in the polycarbonate. When the molar ratio of 1/30 to the epoxy compound is exceeded, the production cost of the product may increase due to the increase of the catalyst cost.

The reaction was carried out by adding a reactant epoxy compound and a catalyst to the reactor and then flowing carbon dioxide to remove the air from the reactor, and then applying a carbon dioxide pressure of a desired value to the reactor, followed by a microwave irradiation device having a microwave irradiation device having a frequency of 2.45 GHz. The copolymerization reaction is carried out in the device.

It is preferable that the said microwave copolymerization reaction time is 1 to 60 minutes. The carbon dioxide pressure of the reaction is preferably 10 to 200 psi.

When the microwave copolymerization reaction time is less than 1 minute or the carbon dioxide pressure is less than 10 psi, the irradiation time of the microwave is too short or the amount of carbon dioxide is insufficient and the reaction time is not sufficiently reacted with the epoxy compound. If the yield of the polycarbonate is prolonged or the polycarbonate is deteriorated, the microwave copolymerization reaction time exceeds 10 minutes or the carbon dioxide pressure exceeds 200 psi. There is a possibility that the yield may decrease.

Hereinafter, the present invention will be described in detail through examples. However, the scope of the present invention is not limited only to these Examples.

<Example 1>

10 mg of zinc cobalt cyanide catalyst was injected into 5 ml of phenylglycidyl ether, the carbon dioxide pressure was adjusted to 50 psi, and the microwave power was adjusted to 100 W for 40 minutes to prepare a polycarbonate copolymer from epoxide and carbon dioxide. It was. The number average molecular weight (M _n ) analyzed using gel permeation chromatography (GPC) and proton nuclear magnetic resonance analyzer ( ¹ H-NMR) was 5359, and the carbon dioxide content was 2.91%.

<Examples 2-4>

The reaction was carried out under the same conditions as in Example 1, but the molecular weight and yield of the polycarbonate copolymer prepared after changing the power and reaction time of the microwave are shown in Table 1 below.

Molecular weight, yield and carbon dioxide content according to microwave power and reaction time Example Microwave Power (W) Response time (minutes) Number average molecular weight Dispersion Yield (%) CO2 Content (%) One 100 40 5359 2.98 86.1 2.9 2 200 7 4361 1.69 91.9 4.8 3 300 6 4497 2.89 97.8 5.7 4 400 6 4197 2.62 99.7 3.9

As can be seen in Table 1, the polycarbonate yield was higher as the microwave power was increased even though the reaction time was shortened. However, the higher the molecular weight, the longer the reaction at low microwave power was able to obtain a high molecular weight copolymer.

<Examples 5 and 6>

The reaction was carried out under the same conditions as in Example 3, but the carbon dioxide pressure was adjusted to 100 and 140 psi and the reaction was carried out to synthesize a copolymer, and the molecular weight and yield thereof are shown in the following [Table 2].

Effect of CO2 Pressure Example Microwave Power (W) CO2 pressure (psi) Number average molecular weight Dispersion Yield (%) CO2 Content (%) 3 300 6 4497 2.89 97.8 5.7 5 300 6 8200 2.7 98.9 9.5 6 300 6 13100 2.60 99.2 14.2

As can be seen from [Table 2], when the reaction was carried out at high pressure, a polycarbonate copolymer having a high average molecular weight and a high carbon dioxide content was obtained.

<Example 7, 8>

The reaction was carried out under the same conditions as in Example 2, but after the preparation of the polycarbonate copolymer using a cyclohexene oxide of the reactant epoxy compound is shown in the molecular weight and yield, etc. [Table 3] below.

Results of Polycarbonate Preparation from Other Epoxide Reactants Example Epoxide Microwave Transfer (W) Response time (minutes) Number average molecular weight Dispersion CO2 Content (%) 2 PGE 200 7 4361 1.69 4.76 7 CHO 200 7 4036 1.63 21.4 8 SO 200 7 2658 1.35 32.7

As can be seen in Table 3, the copolymerization reaction of cyclohexene oxide has a low yield for phenylglycidyl ether, but a relatively high carbon dioxide content can be obtained.

<Comparative Examples 1 to 3>

Epoxy compound and carbon dioxide were reacted by general heating reaction at 140 psi pressure condition using 20 mg of zinc cobalt cyanide catalyst without microwave, and the copolymer was synthesized. Indicated.

Experimental Results of Copolymerization of Epoxy Compounds and Carbon Dioxide by Normal Heating Comparative example Epoxide Reaction temperature (℃) Response time (hr) Number average molecular weight Dispersion CO2 Content (%) One PGE 50 36 9300 3.60 10 2 CHO 50 4 6800 1.81 50 3 CHO 80 4 8900 1.67 53

As can be seen in Table 4, the reaction time in the general heating condition can be seen that the reaction must be performed for a long time with respect to the reaction using the microwave.

Seen from above Although the superiority of the polycarbonate manufacturing method according to the present invention has been described in detail through the above embodiments, the present invention is not necessarily limited only to the above embodiments, and various modifications may be carried out in addition to the above specific embodiments. .

As described above, the present invention having the above-described structure uses a carbon dioxide, which is a cause of global warming, to put an epoxy compound and a metal cyanide catalyst together in a reactor, and then copolymerizes using microwave to produce polycarbonate in a high yield within a short time. Prepared. Polycarbonate production method of the present invention is expected to be very effective because it can increase the polymerization rate and simplify the external heating device by inducing heat generation in the raw material by the microwave.

Claims (5)

Method for producing a polycarbonate, characterized in that to produce a compound of formula 1 by copolymerizing the epoxy compound and carbon dioxide in the presence of a catalyst using a microwave. Formula 1

Where R is

ego, And the range of the repeating unit m, n of the two monomers constituting the produced polycarbonate copolymer is 2 ~ 100, respectively The method of claim 1, The catalyst is a polycarbonate using a microwave, characterized in that the zinc cobalt cyanide prepared from K ₃ [Co (CN) ₆ ] and zinc halide. The method according to claim 1 or 2, The amount of the metal cyanide catalyst is a polycarbonate manufacturing method using a microwave, characterized in that the molar ratio of 1/30 to 1/100 with respect to the epoxy compound. The method of claim 1, The pressure of the carbon dioxide is a polycarbonate manufacturing method using a microwave, characterized in that 10 to 200 psi. The method of claim 1, The microwave copolymerization reaction time is polycarbonate manufacturing method using microwave, characterized in that 1 to 60 minutes.