JPH02142824A - Carbonate copolymer and its production - Google Patents

Abstract

PURPOSE:To obtain the title copolymer desirable as a drug carrier for a drug delivery system by polymerizing an alkylene oxide with an epihalohydrin and CO2 in the presence of a porphyrin aluminum complex and an active hydrogen compound. CONSTITUTION:An alkylene oxide is polymerized with an epihalohydrin and CO2 in the presence of a porphyrin aluminum complex and an active hydrogen compound (e.g., methanol) to produce a carbonate copolymer of a number- average MW of 500-5000, composed of randomly arranged 5-70mol% repeating units of formula I (wherein R is H or an alkyl), 5-70mol% repeating units of formula II (wherein X is a halogen atom) and 25-50mol% repeating units of formula III (provided that the sequence of two or more repeating units of formula III is excluded). According to the above, a copolymer which is composed of randomly arranged repeating units derived from the three components, whose compositional ratio among the three components can be easily changed and which has a narrow MW distribution and is desirable as a drug carrier or the like for a drug delivery system can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a carginate copolymer in which repeating units based on alkylene oxide, epihalohydrin and carbon dioxide are randomly arranged, and a method for producing the same.

(Prior art and problem to be solved by the invention) Polypropylene carnate obtained by polymerizing propylene oxide and carbon dioxide using an organic zinc catalyst has a carbonate bond in its molecular chain and is It has decomposition and thermal decomposition properties.

For this reason, the above-mentioned polyzolopyrene car & carbon #1 may be used as a binder for preparing ceramic green sheets or as a carrier for pharmaceuticals in drug delivery systems.

Pharmaceutical carriers in drug delivery systems are
It is preferable that a pharmacologically active substance or an affected area-directed substance can be introduced through chemical bonding, and that the amount introduced can be completely controlled, and for this purpose it is desirable to contain a chemically active functional group in the molecular chain in any proportion.

(Means for Solving the Problems) The present inventor has already succeeded in producing a polymer having a chloromethyl group based on epichlorohydrin in its molecular chain by completely copolymerizing epichlorohydrin and carbon dioxide (Patent Application No. 63 -185394).

So, the above polyzolopylene car? With the aim of introducing a repeating unit based on epihalohydrin into the molecular chain of nate and imparting a chemically active halomethyl group,
We attempted to copolymerize alkylene oxide and carbon dioxide by adding all of evino-rohydrin. As a result, 3 of alkylene oxide and shrimp/carbon dioxide
It is possible to obtain a copolymer in which the repeating units based on the components are randomly arranged, and the composition ratio of the repeating units based on the three components mentioned above can be easily changed. The present invention has been completed based on the discovery that a copolymer suitable as a carrier for pharmaceuticals, etc. in a drug delivery system can be obtained.

That is, the present invention provides: a) 5 to 70 moles of repeating units represented by the formula [A) 1 [A] -CH2-CH-0- (wherein, R is a hydrogen atom or an alkyl group), and b) the formula [B] -CH2-CH-0- (wherein, X is) a 10 ton atom. ) 5 to 70 molty repeating units represented by the formula [C] +I [C]C-0- 25 to 50 molty repeating units represented by formula Two or more cannot be arranged consecutively. ), number average molecular weight is 50
0 to 50,000.

In the above formula [A], the alkyl group represented by R is not particularly limited in the number of carbon atoms, but may have 1 to 4 carbon atoms from the viewpoint of polymerizability.
It is preferable that In the above formula [B], the halodane atom represented by X is preferably a halodane atom of chlorine, bromine, or iodine.

The ratio of the repeating units represented by the formulas [A:], [:B) and [C] is such that the repeating units represented by the formulas [A) and CB] are 5 to 70 molt, respectively; , l has 25 to 50 moles of repeating units. Formula [B
] The higher the proportion of repeating units represented by , the greater the number of chemically active functional groups and the easier chemical modification becomes, but on the other hand, problems such as biotoxicity after decomposition in living organisms occur. There is a fear. Therefore, the repeating unit represented by formula [B] is preferably 10 to 50 moles, more preferably 15 to 40 moles. The repeating unit represented by formula [C] can be incorporated into the resulting carbonate copolymer in an amount of up to 50 moles. If the proportion of repeating units represented by formula [C] increases, the biodegradability of the resulting cargo copolymer will improve.
Further, it is preferably in the range of 40 to 50 moles.

The cargoate copolymer of the present invention has the above formula [A], [
The repeating units represented by B) and [C] are arranged randomly. However, since it is impossible for two or more repeating units represented by formula (C) to be arranged consecutively in terms of chemical bonding, the repeating unit represented by formula [C] must have the repeating units represented by formula [A] on both sides. Or it is occupied by the repeating unit indicated by [B].

Therefore, the repeating unit represented by the above formula [C] must be of the formula [E] ) -CH2-CH-0-C-0- (However, X is a halodane atom.) It is contained in the molecular chain of the carbonate copolymer of the present invention in the form of each repeating unit represented by the following.

The carbonate copolymer of the present invention usually has a number average molecular weight in the range of 500 to 50,000. When the carbonate copolymer of the present invention is used as a carrier for pharmaceuticals in the aforementioned drug delivery system, the number average molecular weight is preferably in the range of 1,000 to 20,000 from the viewpoint of moldability.

Furthermore, the carbonate copolymer of the present invention has a narrow molecular weight distribution expressed by the ratio of weighted average molecular weight (Mw) to number average molecular weight (Mn), and usually My/Mn≦1.5, and It is also possible to set Mw/Mn≦1.3. As described above, the carginate copolymer of the present invention has a small molecular weight distribution and can reduce molecular weight dependence in vivo, and is therefore well suited as a carrier for pharmaceuticals in the drug delivery system described above. I can say it.

When the manufacturing method described below is followed, one terminal of the carnate copolymer of the present invention is a residue obtained by removing a hydrogen atom from an active hydrogen compound, and the other terminal is a hydroxyl group. . For this reason, a compound with a double bond in the molecule as an active hydrogen compound? If selected, a carbonate copolymer having a double bond at the end of the molecule can be obtained.

In addition, the car obtained by copolymerization with nate copolymer,
A double bond is introduced at the end of the hydroxyl group side of a carbonate copolymer by reacting a compound having a double bond and a halodane atom in the molecule, such as allyl bromide, acrylic acid chloride, or methacrylic acid chloride. can do.

Such carbonate copolymers are used as synthetic materials for stimuli-responsive dull compounds by fully utilizing the reactivity of the double bond at the end of the molecule, and for special grade synthetic resin materials by copolymerizing with vinyl chloride, propylene, etc. can do.

The above-mentioned terminal groups having double bond gold include allyloxy group, acryloyloxy group, methacryloyloxy group,
Examples include styryloxy group.

The carbonate copolymer of the present invention generally exists as a white powder in the case of a high molecular weight substance, or as a colorless and transparent waxy substance in the case of a low molecular weight substance. It is soluble in methanol, water, etc.

The structure of the carbinate copolymer of the present invention was determined by infrared absorption spectrum (hereinafter simply referred to as IR), 'H-nuclear magnetic resonance spectrum (hereinafter simply referred to as 'H-NMR), and elemental analysis. It can be confirmed.

In addition, the number average molecular weight (Mn) and the weight average molecular weight jl (
Mw) B) rA/hermies can be determined by cycloatography (hereinafter simply referred to as GPC). Also, what about differential scanning calorimetry (hereinafter simply referred to as DSC)? The glass transition point of Rimmer (hereinafter simply referred to as Tg) can be determined.

Although the carbonate copolymer of the present invention may be produced by any method, the following method is generally suitably employed.

That is, it is a method of copolymerizing alkylene oxide, epihalohydrin, and carbon dioxide in the presence of a porphyrin aluminum complex and an active hydrogen compound. As the alkylene oxide, known compounds such as ethylene oxide, propylene oxide, butylene oxide, pentylene oxide, etc. can be employed. Further, as the epihalohydrin, known compounds such as epichlorohydrin, epibromohydrin, and ebiodohydrin can be employed.

The porphyrin aluminum complex used as a catalyst is
Although not particularly limited, a compound represented by the following formula ("F) is preferably used in the present invention to ensure that the above three components can be copolymerized well.

It is obtained by reacting a (lO) compound with an organoaluminum compound.

The porphyrin aluminum value body represented by the above formula CF) is a porphyrin represented by the following formula [G] [However, R1-
R20 is the same as the above formula [F]. ]The above formula [G]
Specific examples of the porphyrin compound represented by the above include tetrabenzporphyrin, tetranaphthoporphyrin, tetraphenyltetrabenzporphyrin, and tetraphenyltetranaphthoporphyrin.

Examples of organoaluminum compounds that are raw materials for the porphyrin aluminum complex represented by the above formula [F] include dialkylaluminum halides having an alkyl group having 4 or less carbon atoms, such as diethylaluminum chloride and diethylaluminum bromide; trimethylaluminum, triethylaluminum , trizorobylaluminium, triisobutylaluminum, etc.
The following trialkylaluminums having an alkyl group; alkylaluminum hydrides having an alkyl group having 4 or less carbon atoms and a hydrogen atom, such as diethylaluminum hydride and diisobutylaluminum hydride, are effectively used. Among these, dialkyl aluminum hydrides are preferred.

Since the electrical properties of the reaction between the porphyrin compound and the organoaluminum compound vary depending on the type of raw materials and solvent used, suitable conditions may be selected in advance to carry out the reaction. Generally, the reaction is carried out by adding approximately equimolar amounts of organoaluminium compound gold to the porphyrin compound at a temperature of 0 to 50°C for several tens of minutes to ten hours in the presence of a solvent in an inert gas atmosphere such as nitrogen or argon. .

Further, although the reaction generally proceeds sufficiently at normal pressure, the pressure may be increased or reduced as necessary.

As the reaction solvent, hydrocarbons such as benzene, toluene, and xylene, and halodanized hydrocarbons such as methylene chloride, chloroform, and dichloroethane are used.

When X in the formula CF) of the aluminum porphyrin complex thus obtained is a hydrogen atom or an alkyl group, it is reacted with an organic compound containing a hydroxyl group or water to convert X into an alkoxy group, a phenoxy group, Such complex compounds that can be converted into hydroxyl groups can also be used as catalysts in the present invention. Examples of the porphyrin aluminum complex that can be preferably used in the present invention include tetrabenzporphyrin aluminum chloride complex, tetranaphthoporphyrin aluminum chloride complex, tetraphenyltetrabenzporphyrin aluminum chloride complex, tetraphenyltetranaphthoporphyrin aluminum chloride complex, and tetrabenzporphyrin aluminum chloride complex. Examples include methyl complex, tetranaphthodelphyrin aluminum methyl complex, tetraphenyltetrabenzporphyrin aluminum methyl complex, tetraphenyltetranaphthoporphyrin aluminum methyl complex, and tetrabenzporphyrin aluminum ethyl complex.

As the active hydrogen compound used in combination with the porphyrin aluminum complex of the present invention, for example, alcohols containing one or two or more hydroxyl or carboxylic acid groups per molecule, phenols, and carboxylic acids are effectively used. . Alcohols include aliphatic alcohols such as methanol, ethanol, zolopanol, and butanol; allyl alcohol, vesicular H-flucols such as 2-hydroxyethyl methacrylate; ethylene glycol, triethylene glycol, tripropylene glycol, glycerin, and pentaerythritol. Examples include aliphatic polyhydric alcohols such as. As phenols, phenol,
Examples include phenols such as bisphenol, vinylphenol, and allylphenol; and polyhydric phenols such as resorcinol, P-dihydroxybenzene, and 2.4-)luenediol. Carzenic acids include carnoic acids such as acetic acid, acrylic acid, and methacrylic acid, and polyhydric carboxylic acids such as adipic acid, sebacic acid, maleic acid, fumaric acid, and terephthalic acid. Examples include phosphoric acid.

The active hydrogen compounds are not limited to those shown above, but include various alcohols, phenols, and carbon dioxide. phosphoric acids are used effectively.

The polymerization conditions in the present invention are such that the reaction monomer is polymerized in a solvent in an atmosphere substantially free of active gases other than gas. The nuclear solvent is not particularly limited as long as it is a nonaqueous solvent that does not react with the monomer or the porphyrin aluminum complex. For example, methylene chloride, benzene, etc. are used.

The amounts of alkylene oxide and epihalohydrin may be determined depending on the ratio of repeating units based on the above-mentioned components in the target carbonate copolymer.

The amount of porphyrin aluminum complex used is, per 1 mole of alkylene oxide and epihalohydrin in total,
In the range from 0.001 to 1 mol, especially from 0.001 to 0.1
Preferably, it is used in a molar range.

The amount of the active hydrogen compound to be used is 1 to 50 times the mole of the porphyrin aluminum complex, preferably 1 to 25 times the mole of the porphyrin aluminum complex.
It is in the double molar range.

The pressure of carbon dioxide influences the proportion of repeating units represented by the above formula [C] in the carbonate copolymer obtained. In order to obtain the carbonate copolymer of the present invention,
It is sufficient to select the pressure of carbon dioxide from the range of 1 to 50 atm, preferably from the range of 25 to 50 atm.

The polymerization temperature is generally in the range of -20 to 100°C. Does increasing the polymerization temperature result in a cyclic car? It is preferable to carry out the polymerization at a temperature of 50° C. or lower because nate is likely to be produced as a by-product.

In this way, the carbonate copolymer of the present invention can be obtained.

Furthermore, among the carbonate copolymers of the present invention, the formula (
B) in which X is a bromine or iodine atom can also be produced by total reaction of a carbonate copolymer in which X is chlorine with an alkali metal bromide or alkali metal iodide such as KBr or KI. .

(Effects) The carnate copolymer of the present invention has a chemically active haloalkyl group in its molecular chain, so by chemically modifying all of this active site, it is different from conventional polypropylene cars. It is possible to express functions that are not present in Nate. Further, since the amount of haloalkyl groups in the carbonate copolymer can be arbitrarily controlled depending on the amount of repeating units based on epihalohydrin, the amount introduced can be adjusted appropriately depending on the type of chemically modified product. Further, since the carbonate copolymer of the present invention has a narrow molecular weight distribution, it is optimally used for polymers for which the expression of effects is dependent on molecular weight, such as pharmaceutical polymers.

Therefore, the carnate copolymer of the present invention can be immobilized by reacting a pharmacologically active substance or a substance directed to an affected area with the noroalkyl group, selectively transport these substances to the affected area in the body, and decompose there. It can be used as a carrier for pharmaceuticals in drug delivery systems that release these substances in a sustained manner.

(Examples) The present invention will be fully explained below with reference to Examples, but the present invention is not limited to these Examples.

Example 1 Potassium phthalimide 21g 1 Maron! ! ! 14.7g
, a mixture of 18.9 g of zinc acetate dihydrate was heated under a nitrogen stream,
A zinc complex of tetrabenzporphyrin obtained by reaction at 360 to 370°C for 2 hours was demetalized with sulfuric acid to obtain tetrabenzporphyrin.

0.05 mmol of tetrabenzporphyrin and 0.10 mmol of diethylaluminum chloride
1- in methylene chloride under nitrogen for 5 hours,
In order to distill off excess diethylaluminium chloride, vacuum drying was performed at 50° C. for 3 hours to obtain a blue-green powder.

This tetrabenzporphyrin aluminum chloride complex (hereinafter referred to as (TBP) AtC1) 0.05 m
A 5-fold molar amount of methanol was placed in a round bottom flask containing 5 mol of methanol under a nitrogen atmosphere, and then 0.0 molar of propylene oxide was added.
A homogeneous mixture containing 9-epichlorohydrin i, oy'l was prepared using S with an internal volume of 50 cc, which had been replaced with C02 in advance.
Transferred to US Lou autoclave under nitrogen flow and reduced CO2k.
It was filled with 50 kl//etn2 under pressure and polymerized at room temperature for 101 hours. The obtained reaction product was dissolved in chloroform, precipitated with methanol, purified by reprecipitation to remove all unreacted monomers, and then dried under vacuum.

The structure of this polymer was determined by the following analytical method.

[Molecular weight and molecular weight distribution]

The number average molecular weight (Mn), weight average molecular weight (M, ), and the ratio Mw/Mn f were determined by glupermeation chromatography (GPC) based on a calibration curve using standard polystyrene. As a result, Mn=360
The ratio My/Mn was 1.30.

[Molecular structure]

(2) The functional groups present in the chain were identified by infrared absorption spectroscopy (IR) (the chart is shown in Figure 1).

Peaks originating from carbonate bonds at 1740 and 1230cW1-' Peaks originating from chloromethyl groups at 750-780m-' Peaks originating from ether bonds at 1100cm-'
) (-NMR spectra detected all proton species assigned to the following molecular structure based on their chemical shift values.

In the margins below, the molar ratios of the repeating units indicated by (I) to 2 in the polymer chain were determined from the integral ratios. As a result, (1)
:Ql):(g):ω=44:36:13 (mol%) All carbon species present in the polymer were detected by 13C-NMR spectrum measurement. The measurement was carried out by the proton complete decoupling method, and the solvent used was a 1:1 mixture of heavy benzene and light benzene. Figure 2 shows the chart. Also, in Figure 3 (&), especially Cal? An enlarged view of the region based on nil carbons is shown.

Among these peaks, there are peaks that do not exist in the binary polymer of propylene oxide and carbon dioxide (Figure 3 (b)) and the binary copolymer of epichlorohydrin and carbon dioxide (Figure 3 (C)). was detected.

From this, it was confirmed that the obtained polymer was not a simple mixture or block copolymer of each copolymer of propylene oxide and carbon dioxide or epichlorohydrin and carbon dioxide, but was a random copolymer of the above three components.

■ Through elemental analysis, we were able to determine the ratio of the elements that make up the polymer and obtained the following values.

Actual weight ratio C: 40.3%, H: 4.6%, Ct: 035.0%, Ct: 20.1%. Also, the molar ratio of propylene oxide: shrimp chlorohydrin: carbon dioxide determined from H-NMR (25:35:40) The theoretical elemental analysis values obtained from are as follows.

Theoretical weight ratio C40.9%, H5.0%, 034.7%,
Ct19.3%H-
It was confirmed that the composition ratio determined from NMR was correct.

[Thermal properties]

Differential scanning calorimetry (DSC) was measured to determine the glass transition point (Tg) of the polymer. One point at Tg=-16°C was observed.

Examples 2 to 5 In the same manner as in Example 1, l! Ill! Did (TBP)
A ternary copolymerization reaction of propylene oxide, epichlorohydrin, and carbon dioxide was carried out using the IVC1 complex and methanol under the conditions listed in Table 1. The analysis results of the obtained polymer are also listed in Table IK.

Furthermore, it was confirmed from the C-NMR results that all polymers were random copolymers.

Below are blank spaces Example 7 0.05 mmol of tetrabenzporphyrin and 0.1 triethylaluminum obtained in the same manner as in Example 1
After reacting in ynmol f l-methylene chloride under a nitrogen atmosphere for 5 hours, vacuum drying was carried out at air temperature for 3 hours to remove excess triethylaluminum to obtain a blue-green powder. This tetrabenzporphyrin aluminum ethyl complex (hereinafter referred to as CTBP) AtEt. ) 0. '
Add 0,06 m to the eggplant flask containing 05 mynol.
Add mol of allyl alcohol 1-ethyl chloride y,
After reacting at room temperature for 24 hours, allyl alcohol remaining unreacted with the solvent was removed under reduced pressure. This complex 0.0
A 5-fold molar amount of allyl alcohol was placed in an eggplant flask containing 5 mmol under a nitrogen atmosphere, and then 0.9 mg of propylene oxide was added! The internal volume of the homogenized mixture containing 1-bicu-tetrahydrin was replaced with CO7 in advance.
The mixture was transferred to a 0 cc (D) stainless steel autoclave under a nitrogen stream, filled with CO2 under pressure at 9/m2, and polymerized at room temperature for 100 hours.

The obtained reaction product was divided into two parts, and one part was charged with 0.5 mmol 1
of allyl bromide was added and reacted at 50°C for 5 hours. Both reaction solutions were purified by reprecipitation with chloroform-methanol and vacuum dried to obtain two types of polymers.

The structures of these two types of carbonate copolymers were determined by the following analytical methods.

[Molecular weight and molecular weight distribution]

Obtained by GPC. As a result, the number average molecular weight (Mn
) was 1=4000 for all carbonate copolymers, and the molecular weight distribution was Mw/Mn=1.25.

[Molecular structure]

■ The following peak was detected in the IR spectrum.

1740.1230cIn is the peak of cargo bond 750-780G is the peak of chloromethyl group 110
In the H-NMR spectrum, all peaks attributed to the repeating units represented by (1) to □□□ in Example 1 and peaks attributed to the following formula were detected at 0-1. .

Also, the molecular weight of the cargoate copolymer per one allyloxy group at the molecular end determined from the integral ratio is:
The carbonate copolymer reacted with allyl bromide has Mn = 2700, and the one that does not react has Mn = 4.
';l Q Q. End group 1 estimated from the GPC results that both ends and one end are allyloxy groups
The molecular weight of Koatashi's carbonate copolymer is M
Since n÷2000 and seed=4000, the introduction rates of allyloxy groups into the two types of carbonate copolymers were 75% and 50% at both ends, respectively.

In addition, the composition ratio determined by the integral ratio is the molar ratio of the repeating units represented by (1) to ω in Example 1 -r:, (1
):(I[):Q[D:v)=s6:36:4
: It was 4.

(2) It was confirmed by the 15C-Todoroki vector that the obtained polymer was a random copolymer.

[Thermal properties]

According to the DSC spectrum, the Tg of the obtained polymer is -
The temperature was 13°C.

Examples 8 to 14 All the allyl alcohol and allyl bromide of Example 7 were changed to synthesize ternary random copolymers having different end group structures. The reaction conditions and analysis results are summarized in Table 2.

However, catalysts, active hydrogen compounds, propylene oxide,
The amount of epichlorohydrin charged is 0.05 m each.
mol m 0.25 mmol, 12.5 ynm
ol and 12.8 mmol, and the carbon dioxide pressure was 50 kg/crn2.

Margin below Example 15 Carnate copolymer obtained in Example 1 1g 1100
-5 g (30 mmol) of KI dissolved in acetone
The mixture was reacted for 100 hours at room temperature under light transmission, and the reaction product KCt and unreacted KI which were not soluble in acetone were separated. After drying up the organic phase and converting it to chloroform, the organic phase was optically washed with water to remove any KI that had been mixed in. After drying the organic phase over magnesium sulfate, the chloroform was distilled off to form carnate. A copolymer was obtained.

The yield of the resulting carnate copolymer was 1.4 g, which was in very good agreement with the theoretical yield calculated assuming that all chloromethyl groups were converted to methyl iodide groups.

Furthermore, GPC analysis of the obtained carnate copolymer revealed that the ratio of number average molecular weight (Mn) to weight average molecular weight (MW), Mw/Mn, was 1.30, and there was no disturbance in the molecular weight distribution before and after the reaction. This shows that no side reactions occurred.

Furthermore, in the obtained polymer, the following peaks were detected.

In addition, 3,7 ppm and 3,5 ppm derived from chloromethyl group
The peak at 8 ppm has disappeared, indicating that the reaction is 10
It was confirmed that the progress was 0%. Also, the molar ratio of the repeating units shown in (1) to (goods) above in the obtained polymer is determined by the integral ratio. , (1) : (IF) : ([ID
: GV) = 44:36:13 near.

Example 16 All the same as Example 15 except for changing to KI f KBr.
A reaction was carried out to convert the chloromethyl group in the cargenete copolymer obtained in Example 1 to methyl bromide by the method described in .

According to 'H-NMR of the obtained polymer, the following peaks were detected.

[Brief explanation of the drawing]

Figures 1 and 2 show the infrared absorption spectrum and 13C-
Charts of nuclear magnetic resonance spectra are shown for each gold. Third
The figure is the same.
C-nuclear magnetic resonance spectra of propylene oxide and carbon dioxide copolymers and epichlorohydrin and carbon dioxide copolymers. The nil carbon regions are shown respectively. Furthermore, the disappearance of the peak at 3.70 ppm derived from the chloromethyl group revealed that the reaction had proceeded 100%. In addition, the polymer obtained from the fact that there is no change in MW/Mn determined by GPC analysis and no decrease in molecular weight is observed has a repeating unit nomolar ratio shown in (1) to (conversion) above, (I): ( 10: QID: O
It was concluded that the copolymer was a ternary random copolymer with a ratio of V) = 44:36:13.

Claims (2)

[Claims] (1) A) Formula [A] ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ [A] (However, R is a hydrogen atom or an alkyl group.) 5 to 70 mol% of repeating units, B) Formula [B] ▲Mathematical formulas, chemical formulas, tables, etc.▼[B] (However, X is a halogen atom.) Repeating units of 5 to 70 mol%, and c) Formula [C
] ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ 25 to 50 mol% of repeating units represented by [C] are arranged randomly (however, two or more repeating units represented by formula [C] are arranged consecutively) ), a carbonate copolymer having a number average molecular weight of 500 to 50,000. (2) A method for producing a carbonate copolymer according to claim (1), which comprises polymerizing alkylene oxide, epihalohydrin, and carbon dioxide in the presence of a porphyrin aluminum complex and an active hydrogen compound.