JP3091207B2 - Lactone polymer and method for producing the same - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a technology for producing a lactone polymer using a cyclic lactone as a raw material. More specifically, the present invention relates to a method for producing a lactone polymer having a high molecular weight by using an organic rare earth metal compound as a catalyst. The present invention relates to a technique for producing a lactone polymer having a narrow molecular weight distribution.

[Prior Art] Cyclic lactone polymer having a molecular weight of 10,000 to 100
As the high-molecular-weight polymers reaching 10,000, only so-called wide-dispersion polymers having a wide molecular weight distribution have been produced. However, such a polymer is inferior in practicality due to its wide dispersion type, and cannot be used in fields requiring high strength such as films and fibers. Cyclic lactone polymers used as raw materials for urethane resins and the like have been found to have a degree of dispersion (given by the ratio of weight average molecular weight / number average molecular weight, the same applies hereinafter) of 1.1 to 2.0. It is at most 10,000.

As a catalyst for the polymerization of cyclic lactones, metal compounds of aluminum, zinc, tin, and titanium have been known so far. However, in the polymerization reaction using these catalysts, even if the reaction is carried out at the lowest temperature, the reaction temperature is from 50 ° C to 150 ° C. Heating to about ° C is required. Generally, to increase the polymerization reaction rate,
Although increasing the reaction temperature and increasing the amount of the catalyst have been carried out, the above-mentioned conventional catalyst is inappropriate when a low-boiling solvent is desired. Also, when the reaction temperature is increased, the tendency to become a cyclic lactone polymer having a wide degree of dispersion appears strongly. On the other hand, when the amount of the catalyst is increased, a large amount of the catalyst coexists in the obtained polymer, and it becomes difficult to remove the catalyst from the reaction mixture. Also, the use of a large amount of catalyst is costly and is not industrially preferable. On the other hand, in the laboratory, it has been studied to obtain a cyclic lactone polymer having a low degree of dispersion by using a low-boiling solvent by lowering the polymerization temperature. Requires a considerably long reaction time, which is not industrially preferable. For these various reasons, a cyclic lactone polymer having a high molecular weight but a narrow dispersity has not yet been found.

[Problems to be Solved by the Invention] The present invention has been made in view of the above-mentioned circumstances, and its object is to use a special catalyst to obtain an excellent reaction efficiency from a cyclic lactone as a raw material. Another object of the present invention is to provide a lactone polymer having a high molecular weight and a narrow molecular weight distribution with a method capable of producing a high molecular weight lactone polymer having a narrow molecular weight distribution. Things.

[Means for Solving the Problems] The structure of the production method according to the present invention, which has solved the above problems, is characterized in that when producing a lactone polymer by polymerizing a cyclic lactone, an organic rare earth metal compound (cerium compound) is used as a catalyst. (Excluding)). In addition, in producing a lactone polymer by polymerizing a cyclic lactone, an organic rare earth metal compound is used as a catalyst and the polymerization is carried out at −78 to 60 ° C. As the organic rare earth metal compound used as a catalyst, an organic lanthanoid-based metal compound, especially an organic lanthanoid-based metal complex compound is preferable, and among these, the compound represented by the following formula [I] is a very excellent catalyst. .

[M · R ¹ _m · A _h ] _k · (AlR ² ₃ ) _p · B _n ... [I] [wherein, M is Sc, Y or a divalent or trivalent lanthanoid rare earth element, and A _h is A But Or And h is 2 or A _h (R ³ is an alkylene group having 1 to 5 carbon atoms or (Q is an integer of 1 to 4), or may be substituted with any number of the hydrogen atoms are the same or different alkyl group or a trimethylsilyl group having 1 to 5 carbon on the carbocyclic compound in the A _h B is diethyl ether or tetrahydrofuran, R ¹ is hydrogen or an alkyl group having 1 to 5 carbon atoms, R ² is an alkyl group having 1 to 5 carbon atoms, m is 0 or 1, n represents 0, 1 or 2, k represents 1 or 2, and p represents 0 or 1. Further, the configuration of the production method according to the present invention has a gist in using an organic lanthanoid-based metal complex compound including a cerium compound as a catalyst in producing a lactone polymer by polymerizing a cyclic lactone,
Among the organic lanthanoid-based metal complex compounds, the compound represented by the above formula [I] is very excellent as a catalyst.

The lactone polymer according to the present invention has a gist in that the number average molecular weight is 10,000 to 1,000,000 and the degree of dispersion represented by weight average molecular weight / number average molecular weight is 1.1 to 1.6. .

[Action] The cyclic lactone used in the present invention has 4 carbon atoms.
To 8 cyclic lactones, among which δ-valerolactone and ε-caprolactone are particularly preferred. These cyclic lactones may be those in which part of the hydrogen bonded to the carbon in the lactone ring has been replaced by a lower alkyl group. The cyclic lactone can be homopolymerized, or can be copolymerized using two or more kinds.

The catalyst used in the present invention is an organometallic compound containing a rare earth element composed of Sc, Y and a lanthanoid element as a metal component, and these can be used alone or in combination of two or more if necessary. It is possible. Among the above organic rare earth metal compounds, preferred are La, Ce, Pr, Nd, Pm, S
m, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, is an organometallic complex compound containing a lanthanoid-based metal such as Lu as a metal component. The best complex compound for achieving the object of the present invention is represented by the formula [I], and specific examples thereof include the following.

M ・ (C ₅ R ₅ ) ₂・ THF M ・ (C ₅ R ₅ ) ₂・ (THF) ₂ M ・ (C ₅ R ₅ ) ₂・ Et ₂ O M ・ (C ₅ R ₅ ) ₂・ (Et ₂ O) ₂ [MH · (C ₅ R ₅ ) ₂ ] ₂ M (Me) · (C ₅ R ₅ ) ₂ · Et ₂ O M (Me) · (C ₅ R ₅ ) ₂ · AlR ₃ [M ( Me) ・ (C ₅ H ₅ ) ₂ ] ₂ M ・ (C ₅ Me ₅ ) ₂・ AlR ₃・ THF M ・ (C ₅ Me ₅ ) ₂・ AlR ₃・ Et ₂ O (where M in the above formula is Same meaning as above, Me is a methyl group,
Et represents an ethyl group, R represents a lower alkyl group such as a methyl group, an ethyl group, an isopropyl group, or an isobutyl group, and THF represents tetrahydrofuran.) The organic rare earth metal complex compound itself as described above is already known. (1) Journal of American Chemical Society, Volume 105 (1983), pp. 1401-1403,
(2) Journal of American Chemical Society, Volume 110 (1988), pp. 6423-6432, WJE
vans et al., (3) Journal of American Chemical Society, Dalton Transactions (1979
Pp. 45-53, J. Holton et al. (4) Journal of American Chemical Society, Dalton Transactions (1979)
54-61, J. Holton et al., (5) Chemistry Letters (1988), 1963-19
Details are published in the literature such as H. Yamamoto et al., P. 66.

These documents show that organic rare earth metal complex compounds are useful as catalysts in the polymerization of ethylene or methyl methacrylate.However, the use of these catalysts in the polymerization of cyclic lactones is not yet clear. For the first time in the present invention, the fact that a polymer having a high molecular weight and a small degree of dispersion can be obtained by using this catalyst for the polymerization of a cyclic lactone has been found.

When the present invention is carried out, the preferable addition amount of the catalyst is in the range of 1 × 10 ^{−4 to} 0.1 mol, more preferably 2 × 10 ⁻³ to 1 × 10 ⁻² mol per 1 mol of the monomer, The preferred concentration of the catalyst with respect to the solvent is 5 × 10 ^-4 to 1 × 10 ^-1
Mol / range. In the polymerization reaction, the organic rare earth element complex compound described above can be used alone.
As described above, more than one kind can be used in combination. Polymerization using this catalyst does not require high temperature,
The polymerization proceeds sufficiently efficiently in the range of from 60 ° C to 60 ° C, more preferably from 0 ° C to 20 ° C, and is completed in a very short time, for example, from 1 minute to 1 hour. If the polymerization is carried out on the lower temperature side in the above preferable temperature range, a polymer having a very narrow dispersity of 1.1 to 1.6 and a high molecular weight can be obtained.

The polymerization reaction is hexane, benzene, toluene, tetrahydrofuran, in a solvent such as diethyl ether, Ar, N ₂
It is preferably performed in an inert gas atmosphere such as the above.

After the polymerization reaction is completed, a protic solvent is added to the reaction system to deactivate the catalyst.Then, the polymer is poured into an insoluble solvent, the insoluble matter is collected, and the polymer is dissolved in acetone. After removal, the solvent is distilled off to obtain the desired polymer. In the polymerization, the polymerization conditions should be adjusted so that the number average molecular weight of the obtained polymer is in the range of 10,000 to 1,000,000. If the number average molecular weight is less than 10,000, satisfactory physical properties cannot be obtained, and if the number average molecular weight exceeds 1,000,000, the moldability deteriorates.

Thus, by using an organic rare earth metal compound as a catalyst when polymerizing a cyclic lactone, a lactone polymer having a high molecular weight and a narrow molecular weight distribution can be produced at a low temperature and at a high polymerization rate. In particular, the lactone polymer obtained by the present invention has a high molecular weight such as a number average molecular weight of 10,000 to 1,000,000 and a dispersity of 1.1 to 1.
With a very narrow molecular weight distribution of 6, it exhibits excellent performance in the following applications.

[Effect of the Invention] The present invention is configured as described above, and a polymer having a narrower degree of dispersion and a higher molecular weight than a conventional polymer of a cyclic lactone can be obtained. The lactone polymer has higher strength characteristics than the conventional cyclic lactone polymer, and can be used as a material such as a film or a fiber. Therefore, the lactone polymer can be widely used as a bottle material and a packaging material in addition to the fields conventionally known as a lactone polymer, for example, a medical material field and a biodegradable material.

[Examples] Next, the contents of the present invention will be specifically described with reference to examples, but the present invention is not limited to the following examples.

The structure of the polymer obtained in each Example was determined by ¹³ C-NMR, and the molecular weight distribution, molecular weight and degree of dispersion were determined by gel permeation chromatography (hereinafter abbreviated as GPC). As a device, ¹³ C-NMR is
VarianXL-300 was used. ¹³ C-NMR was measured at 75 MHz using a 20% by weight solution of d-form chloroform (d represents deuterium) (1 v of tetramethylsilane was used as an internal standard).
d-form chloroform containing / v% was used).

The following apparatus was used for GPC measurement, and polystyrene was used for the calibration curve.

Apparatus: Hitachi 655A-12 Solvent: Chloroform 1ml / min Temperature: 40 ° C Column: Showa Denko shodex K-805 1 K-804 1 K-803 1 K-802 1 Detector: Showa Denko shodex RI- 51 Example 1 1 ml of toluene and 0.0% of [SmH (C ₅ Me ₅ ) ₂ ] ₂ were placed in Schlenk in an argon gas atmosphere after removing air and moisture.
2 mmol and ε-caprolactone were sequentially added in an amount of 9 mmol, and polymerized at 25 ° C. for 15 minutes. After the polymerization was completed, a small amount of methanol was added to make the catalyst inactive, and then 30 ml of ether was added. The insoluble matter was taken out and dissolved in 30 ml of acetone. The acetone-insoluble matter was removed, and acetone was removed from the acetone-soluble matter to obtain a target cyclic lactone polymer. The yield was 99% and the polymer was a white film-like solid.

Weight average molecular weight (hereinafter referred to as "Mw") 118,500 Number average molecular weight (hereinafter referred to as "Mn") 79,900 Dispersity (hereinafter referred to as "Mw / Mn") 1.48 Example 2 Air and water were removed to make Schlenk an argon gas atmosphere 0.77 ml of toluene and [SmH (C ₅ Me ₅ ) ₂ ] ₂
0.015 mmol, 1.14 mmol of ε-caprolactone were added sequentially to 25
Polymerization was carried out at 1 ° C. for 1 hour. After the polymerization was completed, a small amount of methanol was added to make the catalyst inactive, and then 30 ml of ether was added. The insoluble matter was taken out and dissolved in 30 ml of acetone. The acetone-insoluble matter was removed, and acetone was removed from the acetone-soluble matter to obtain a target cyclic lactone polymer. The yield was 55% and the polymer was a white film-like solid.

Mw 56,000 Mn 47,000 Mw / Mn 1.19 FIG. 1 is a GPC (gel permeation chromatography) chart of the obtained polymer.

Example 3 1 ml of toluene and 0.0% of [SmH (C ₅ Me ₅ ) ₂ ] ₂ were placed in Schlenk in an argon gas atmosphere after removing air and moisture.
2 mmol and ε-caprolactone were sequentially added in an amount of 9 mmol, followed by polymerization at 60 ° C. for 1 hour. After the polymerization was completed, a small amount of methanol was added to make the catalyst inactive, and then 30 ml of ether was added. The insoluble matter was taken out and dissolved in 30 ml of acetone. The acetone-insoluble matter was removed, and acetone was removed from the acetone-soluble matter to obtain a target cyclic lactone polymer. The yield was 61% and the polymer was a white film-like solid.

Mw 68,900 Mn 46,300 Mw / Mn 1.49 Example 4 1 ml of toluene and 0.0% of [YbMe (C ₅ H ₅ ) ₂ ] ₂ were placed in Schlenk in an argon gas atmosphere after removing air and moisture.
2 mmol and ε-caprolactone were sequentially added in an amount of 9 mmol, and polymerized at 25 ° C. for 15 minutes. After the polymerization was completed, a small amount of methanol was added to make the catalyst inactive, and then 30 ml of ether was added. The insoluble matter was taken out and dissolved in 30 ml of acetone. Acetone was removed from the acetone-soluble matter obtained by removing the acetone-insoluble matter to obtain a target cyclic lactone polymer. The yield was 85% and the polymer was a white film-like solid.

Mw 80,200 Mn 63,800 Mw / Mn 1.26 Example 5 1 ml of toluene and LuMe (C ₅ Me ₅ ) ₂ .AlMe ₃ were placed in Schlenk in an argon gas atmosphere after removing air and moisture.
0.02 mmol, 9 mmol of ε-caprolactone were sequentially added, and 25
Polymerized for 5 minutes. After the polymerization was completed, a small amount of methanol was added to make the catalyst inactive, and then 30 ml of ether was added. The insoluble matter was taken out and dissolved in 30 ml of acetone. The acetone-insoluble matter was removed, and acetone was removed from the acetone-soluble matter to obtain a target cyclic lactone polymer. The yield was 89% and the polymer was a white film-like solid.

Mw 72,900 Mn 58,200 Mw / Mn 1.25 Example 6 1 ml of toluene and 0.02 mm of Yb (C ₉ H ₇ ) ₂ · THF were removed in a Schlenk with air and water removed and in an argon gas atmosphere.
ol and ε-caprolactone were sequentially added in an amount of 9 mmol, and the mixture was polymerized at 25 ° C. for 15 minutes. After the polymerization was completed, a small amount of methanol was added to make the catalyst inactive, and then 30 ml of ether was added. The insoluble matter was taken out and dissolved in 30 ml of acetone. Acetone was removed from the acetone-soluble matter obtained by removing the acetone-insoluble matter to obtain a target cyclic lactone polymer. The yield is 90% and the polymer is a white film-like solid.

Mw 85,000 Mn 70,600 Mw / Mn 1.20 Example 7 1 ml of toluene and 0.1 ml of YbMe (C ₅ Me ₅ ) ₂ · Et ₂ O were placed in a Schlenk with air and moisture removed and in an argon gas atmosphere.
02 mmol, 9 mmol of ε-caprolactone were sequentially added, and 25
Polymerized for minutes. After the polymerization was completed, a small amount of methanol was added to make the catalyst inactive, and then 30 ml of ether was added. The insoluble matter was taken out and dissolved in 30 ml of acetone. The acetone-insoluble matter was removed, and acetone was removed from the acetone-soluble matter to obtain a target cyclic lactone polymer. The yield was 93% and the polymer was a white film-like solid.

Mw 65,300 Mn 53,900 Mw / Mn 1.21 Example 8 1 ml of toluene and Yb (C ₅ H ₄ .SiMe ₃ ) _2. (TH
F) 0.02 mmol of ₂ and 9 mmol of ε-caprolactone were added sequentially.
Polymerization was performed at 25 ° C. for 15 minutes. After the polymerization was completed, a small amount of methanol was added to make the catalyst inactive, and then 30 ml of ether was added. The insoluble matter was taken out and dissolved in 30 ml of acetone. The acetone-insoluble matter was removed, and acetone was removed from the acetone-soluble matter to obtain a target cyclic lactone polymer. The yield was 98% and the polymer was a white film-like solid.

Mw 59,300 Mn 46,000 Mw / Mn 1.29 Example 9 1 ml of toluene and 0.0% of [SmH (C ₅ Me ₅ ) ₂ ] ₂ were introduced into Schlenk in an argon gas atmosphere after removing air and moisture.
25 mmol and 10.8 mmol of δ-valerolactone were sequentially added, and the mixture was polymerized at 25 ° C for 1 hour. After the polymerization was completed, a small amount of methanol was added to make the catalyst inactive, and then 30 ml of ether was added. The insoluble matter was taken out and dissolved in 30 ml of acetone. The acetone-insoluble matter was removed, and acetone was removed from the acetone-soluble matter to obtain a target cyclic lactone polymer. The yield was 98% and the polymer was a white film-like solid.

 Mw 135,200 Mn 88,900 Mw / Mn 1.52 FIG. 2 is a GPC chart of the obtained polymer.

Example 10 0.77 ml of toluene and [SmH (C ₅ Me ₅ ) ₂ ] ₂ were introduced into Schlenk in an argon gas atmosphere after removing air and moisture.
0.015 mmol, 1.14 mmol of δ-valerolactone were sequentially added, and 25
Polymerization was carried out at a temperature of 1 hour. After the polymerization was completed, a small amount of methanol was added to make the catalyst inactive, and then 30 ml of ether was added. The insoluble matter was taken out and dissolved in 30 ml of acetone. The acetone-insoluble matter was removed, and acetone was removed from the acetone-soluble matter to obtain a target cyclic lactone polymer. The yield was 55% and the polymer was a white film-like solid.

Mw 73,000 Mn 65,400 Mw / Mn 1.12 Example 11 10 ml of toluene and [SmH (C ₅ Me ₅ ) ₂ ] ₂ were added to Schlenk in an argon gas atmosphere after removing air and moisture.
02 mmol and δ-valerolactone were added in order of 2 mmol and the mixture was added at 60 ° C. for 1 hour.
Polymerized for hours. After the polymerization was completed, a small amount of methanol was added to make the catalyst inactive, and then 30 ml of ether was added. The insoluble matter was taken out and dissolved in 30 ml of acetone. The acetone-insoluble matter was removed, and acetone was removed from the acetone-soluble matter to obtain a target cyclic lactone polymer. The yield was 61% and the polymer was a white film-like solid.

Mw 69,400 Mn 50,400 Mw / Mn 1.38 Example 12 1 ml of toluene and 0.0% of [YbMe (C ₅ H ₅ ) ₂ ] ₂ were introduced into Schlenk in an argon gas atmosphere after removing air and moisture.
2 mmol and δ-valerolactone were sequentially added in an amount of 9 mmol, and the mixture was polymerized at 25 ° C. for 15 minutes. After the polymerization was completed, a small amount of methanol was added to make the catalyst inactive, and then 30 ml of ether was added. The insoluble matter was taken out and dissolved in 30 ml of acetone. The acetone-insoluble matter was removed, and acetone was removed from the acetone-soluble matter to obtain a target cyclic lactone polymer. The yield was 87% and the polymer was a white film-like solid.

Mw 86,400 Mn 70,400 Mw / Mn 1.23 Example 13 1 ml of toluene and LuMe (C ₅ Me ₅ ) ₂ .AlMe ₃ were placed in Schlenk in an argon gas atmosphere after removing air and moisture.
0.02 mmol, δ-valerolactone were added in order of 9 mmol, and 1
Polymerized for 5 minutes. After the polymerization is completed, a small amount of methanol is added to deactivate the catalyst, and then 30 ml of ether is added. The insoluble matter is taken out, dissolved in 30 ml of acetone, acetone-insoluble matter is removed, acetone is removed from acetone-soluble matter, and the desired cyclic lactone weight is removed. A coalescence was obtained. The yield was 95% and the polymer was a white film-like solid.

Mw 54,400 Mn 40,900 Mw / Mn 1.33 Example 14 1 ml of toluene and 0.02 m of Yb (C ₅ Me ₅ ) ₂ · THF were removed in a Schlenk with air and moisture removed and in an argon gas atmosphere.
mol and δ-valerolactone were sequentially added in an amount of 9 mmol, and the mixture was polymerized at 25 ° C for 15 minutes. After the polymerization is completed, a small amount of methanol is added to deactivate the catalyst, and then 30 ml of ether is added. The insoluble matter is taken out, dissolved in 30 ml of acetone, acetone-insoluble matter is removed, acetone is removed from acetone-soluble matter, and the desired cyclic lactone weight is removed. A coalescence was obtained. The yield was 91% and the polymer was a white film-like solid.

Mw 113,700 Mn 90,400 Mw / Mn 1.26 Example 15 1 ml of toluene and YbMe (C ₅ Me ₅ ) ₂ .Et ₂ O were added to Schlenk in an argon gas atmosphere after removing air and moisture.
02 mmol, δ-valerolactone were added in order of 9 mmol and 15 ° C at 25 ° C.
Polymerized for minutes. After the polymerization was completed, a small amount of methanol was added to make the catalyst inactive, and then 30 ml of ether was added. The insoluble matter was taken out and dissolved in 30 ml of acetone. The acetone-insoluble matter was removed, and acetone was removed from the acetone-soluble matter to obtain a target cyclic lactone polymer. The yield is 90% and the polymer is a white film-like solid.

Mw 69,200 Mn 53,800 Mw / Mn 1.29 Example 16 1 ml of toluene and 1 ml of Eu (C ₅ Me ₅ ) ₂ · (THF) ₂ were placed in a Schlenk with air and water removed and in an argon gas atmosphere.
0.02 mmol, δ-valerolactone 9 mmol sequentially added at 25 ° C.
For 15 minutes. After the polymerization was completed, a small amount of methanol was added to make the catalyst inactive, and then 30 ml of ether was added. The insoluble matter was taken out and dissolved in 30 ml of acetone. The acetone-insoluble matter was removed, and acetone was removed from the acetone-soluble matter to obtain a target cyclic lactone polymer. The yield was 99% and the polymer was a white film-like solid.

Mw 92,500 Mn 81,700 Mw / Mn 1.13 Example 17 10 ml of toluene and [YbMe (C ₅ H ₅ ) ₂ ] ₂ were added to Schlenk in an argon gas atmosphere after removing air and moisture.
025 mmol, 5 mmol of ε-caprolactone were added successively at 25 ° C.
Polymerized for hours. Thereafter, 5 mol of δ-valerolactone was added to the system, and polymerization was carried out again at 25 ° C. for 1 hour. After the polymerization is completed, a small amount of methanol is added to deactivate the catalyst, and then ether is added to 30 minutes.
ml was added, the insoluble matter was taken out and dissolved in 30 ml of acetone. The acetone-insoluble matter was removed, and acetone was removed from the acetone-soluble matter to obtain a target cyclic lactone polymer. The yield was 85% and the polymer was a white film-like solid.

Monomer composition ratio (molar ratio) in polymer ε-caprolactone: δ-valerolactone 1.5: 1.0 Mw 81,600 Mn 53,900 Mw / Mn 1.51 FIG. 3 shows ¹³ C of polymer obtained in the first-stage polymerization with ε-caprolactone. FIG. 4 is a ¹³ C-NMR chart of a polymer obtained by adding δ-valerolactone, and FIG. 6 is a GPC chart of both polymers.

Example 18 Air and water were removed, and 10 ml of toluene and 5 mmo of ε-caprolactone were introduced into Schlenk in an argon gas atmosphere.
l, δ-Valerolactone were added in order of 5 mmol, and the mixture was mixed. Thereafter, 0.025 mmol of [SmMe (C ₅ Me ₅ ) ₂ ] ₂ was added, and the mixture was added at 25 ° C.
For 3 hours. After the polymerization was completed, a small amount of methanol was added to make the catalyst inactive, and then 30 ml of ether was added. The insoluble matter was taken out and dissolved in 30 ml of acetone. The acetone-insoluble matter was removed, and acetone was removed from the acetone-soluble matter to obtain a target cyclic lactone polymer. The yield was 85% and the polymer was a white film-like solid.

Monomer composition ratio (molar ratio) in polymer ε-caprolactone: δ-valerolactone 1.5: 1.0 Mw 118,700 Mn 75,600 Mw / Mn 1.57 FIG. 5 shows ¹³ C-NMR chart of the obtained polymer, and FIG. 7 shows GPC It is a chart.

[Brief description of the drawings]

1 is a GPC chart of the ε-caprolactone polymer obtained in Example 2, FIG. 2 is a GPC chart of the δ-valerolactone polymer obtained in Example 9, and FIG. - ¹³ C-NMR chart of what stopped the caprolactone polymerization in the first stage, Figure 4 is subsequent to the δ
About valerolactone added and polymerized
¹³ C-NMR chart, Fig. 5 ¹³ C-NMR Chiyato for a random copolymer of the resulting ε- caprolactone -δ- valerolactone in Example 18, FIG. 6 is a third diagram corresponds in Example 17 GPC chart of polymer (chain line) and polymer corresponding to FIG. 4 (solid line), FIG. 7 shows GPC of polymer corresponding to FIG.
It is a chart.

Claims (7)

(57) [Claims] 1. A method for producing a lactone polymer, which comprises using an organic rare earth metal compound (excluding a cerium compound) as a catalyst in producing a lactone polymer by polymerizing a cyclic lactone. 2. A method for producing a lactone polymer, which comprises polymerizing a cyclic lactone to produce a lactone polymer by using an organic rare earth metal compound as a catalyst and polymerizing at -78 to 60 ° C. 3. The method according to claim 1, wherein the organic rare earth metal compound is an organic lanthanoid metal compound. 4. A method for producing a lactone polymer, which comprises using an organic lanthanoid-based metal complex compound as a catalyst in producing a lactone polymer by polymerizing a cyclic lactone. 5. The method according to claim 3, wherein the organic lanthanoid metal compound is an organic lanthanoid metal complex compound. 6. The production method according to claim 4, wherein the organic lanthanoid metal complex compound is at least one selected from the group consisting of compounds represented by the following chemical formula. [M · R ¹ _m · A _h ] _k · (AlR ² ₃ ) _p · B _n [where M is Sc, Y or a divalent or trivalent lanthanoid rare earth element, and A _h is A Or And h is 2 or A _h (R ³ is an alkylene group having 1 to 5 carbon atoms or (Q is an integer of 1 to 4), or may be substituted with any number of the hydrogen atoms are the same or different alkyl group or a trimethylsilyl group having 1 to 5 carbon on the carbocyclic compound in the A _h B is diethyl ether or tetrahydrofuran, R ¹ is hydrogen or an alkyl group having 1 to 5 carbon atoms, R ² is an alkyl group having 1 to 5 carbon atoms, m is 0 or 1, n is 0, 1 or 2, k is 1 or 2,
p represents 0 or 1, respectively. ] 7. The number average molecular weight is 10,000 to 1,000,000, and the dispersity represented by weight average molecular weight / number average molecular weight is 1.1 to 1.6.
A lactone polymer.