CN110982053A - Organic nonmetal catalyst for preparing poly (p-dioxanone) - Google Patents

Organic nonmetal catalyst for preparing poly (p-dioxanone) Download PDF

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CN110982053A
CN110982053A CN201911317660.1A CN201911317660A CN110982053A CN 110982053 A CN110982053 A CN 110982053A CN 201911317660 A CN201911317660 A CN 201911317660A CN 110982053 A CN110982053 A CN 110982053A
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polydioxanone
catalyst
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organometalloid
ring
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CN110982053B (en
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李博
邱化玉
张永禄
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Hangzhou Normal University
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    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
    • C08G63/78—Preparation processes
    • C08G63/82—Preparation processes characterised by the catalyst used
    • C08G63/87—Non-metals or inter-compounds thereof
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
    • C08G63/02—Polyesters derived from hydroxycarboxylic acids or from polycarboxylic acids and polyhydroxy compounds
    • C08G63/06—Polyesters derived from hydroxycarboxylic acids or from polycarboxylic acids and polyhydroxy compounds derived from hydroxycarboxylic acids
    • C08G63/08—Lactones or lactides
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
    • C08G63/78—Preparation processes
    • C08G63/82—Preparation processes characterised by the catalyst used
    • C08G63/823—Preparation processes characterised by the catalyst used for the preparation of polylactones or polylactides
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
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    • C08G2230/00—Compositions for preparing biodegradable polymers
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Abstract

The invention discloses an organic nonmetal catalyst for preparing polydioxanone, wherein the polydioxanone is subjected to ring-opening polymerization reaction under the action of the organic nonmetal catalyst and an initiator carrying a hydroxyl structure to obtain the polydioxanone, and the structural formula of the organic nonmetal catalyst is selected from one or more of the following components:
Figure DDA0002326277140000011
wherein R is1、R2Each group is independently an aliphatic group or a cyclic group. The organic nonmetal catalyst provided by the invention realizes the high-efficiency ring-opening polymerization of the monomer by activating the functional group in the PDO, and the polymerization reaction has the advantages of high activity, easy regulation and mild reaction.

Description

Organic nonmetal catalyst for preparing poly (p-dioxanone)
Technical Field
The invention belongs to the technical field of organic catalytic systems, and particularly relates to an organic nonmetal catalyst for preparing poly (p-dioxanone).
Background
Since the last century, aliphatic polyesters have been used as biomedical and environmentally friendly materials because of their good biocompatibility, absorbability and biodegradability. As a typical aliphatic polyester, polydioxanone (PPDO) is similar to Polycaprolactone (PCL), polylactic acid (PLA) and polyglycolic acid (PGA), and ester bonds in molecular chains endow the polyester with good biocompatibility, biodegradability and absorbability; the PPDO molecular chain has unique ether bond, and the PPDO molecular chain has excellent flexibility and tensile strength, compared with natural polymer materials (such as chitin, chitosan, gelatin and the like), the PPDO molecular chain overcomes the defect that the mechanical property is reduced due to the influence of a pore structure, so that PPDO is distinguished in the field of biomedicine and is favored by clinical medical treatment.
Generally, aliphatic polydioxanones are prepared by ring opening polymerization of a dioxanone monomer (PDO) (formula I). The choice of catalyst is critical to ring-opening polymerization and commonly used catalysts include tin, aluminum, zinc, and enzymatic catalysis, among others.
Figure BDA0002326277120000011
Kricheldo realizes ring-opening polymerization of PDO by using zinc acetate as a catalyst, and the reaction is carried out under the high-temperature condition, and although the obtained polymer has higher molecular weight, the conversion rate is low. Tokiwa professor of Tokyo university in Japan realizes reversible polymerization of PDO for the first time by using stannous octoate and triethylaluminum as catalysts at 60-180 ℃, the monomer conversion rate can reach more than 95%, the number average molecular weight can reach 30 ten thousand at most, and polymers with higher quality can be obtained. AlEt utilized by Wangyouzhong3-H2O-H3PO4The catalytic system realizes the high-efficiency ring-opening polymerization of PDO under the reaction condition of 80 ℃, the molecular weight is more than one hundred thousand, but the catalytic system mainly comprising metal generally has the defects of long reaction time, low conversion rate and difficult control of side reaction. Although the above-mentioned catalytic system realizes the ring-opening polymerization of PDO, the catalytic system used is mostly a metal catalyst, and lacks modulation factors, resulting in less activity control factors of PDO ring-opening polymerization, and although the regulation can be performed by raising the polymerization temperature and prolonging the reaction time, the side reactions are increased by raising the temperature and prolonging the time, resulting in the phenomena of wider distribution of the polymerization material and decomposition of the product, which are very unfavorable for the subsequent material processing. In recent years, the technology of the present invention has been developedThe organic catalyst is used as an efficient catalytic system to make ring-opening polymerization of cyclic compounds have more possibility.
Disclosure of Invention
The invention aims to provide an organic nonmetal catalyst for preparing polydioxanone, which realizes efficient ring-opening polymerization of monomers by activating functional groups in PDO, and has the advantages of high activity, easiness in adjustment and mild reaction in polymerization reaction.
The technical scheme provided by the invention is as follows:
an organic nonmetal catalyst for preparing polydioxanone, wherein the polydioxanone is subjected to ring opening polymerization reaction under the action of the organic nonmetal catalyst and an initiator carrying a hydroxyl structure to obtain the polydioxanone, and the structural formula of the organic nonmetal catalyst is selected from one or more of the following:
Figure BDA0002326277120000031
wherein R is1、R2Each group is independently an aliphatic group or a cyclic group.
The structural formulas are respectively as follows: thiourea, urea, 7-methyl-1, 5, 7-triazabicyclo [4.4.0] dec-5-ene (MTBD) and 1, 8-diazabicycloundec-7-ene (DBU).
Preferably, the aliphatic group is selected from methyl, ethyl, isopropyl or n-butyl and the cyclic group is selected from phenyl or cycloalkyl.
Preferably, R is1The group is 3, 5-bistrifluoromethylphenyl, R2The group is cycloalkyl or N, N-dimethyl cyclohexylamino, and the structural formula of the organic nonmetal catalyst A is shown as follows:
Figure BDA0002326277120000032
preferably, the organic nonmetal catalyst has a structural formula selected from one or more of:
Figure BDA0002326277120000033
the organic nonmetal catalyst has the advantages of high conversion rate and mild reaction conditions for preparing the polydioxanone, and the prepared polydioxanone has narrow molecular weight distribution.
The initiator is selected from one or more of benzyl alcohol BA, ethylene glycol EG, diethylene glycol DEG and 1, 4-butanediol BDO.
Preferably, the initiator is selected from benzyl alcohol or ethylene glycol.
The ring-opening polymerization reaction is carried out under the condition of no solvent, and the temperature of the ring-opening polymerization reaction is 100-160 ℃.
The ring-opening polymerization reaction is carried out in the presence of a solvent, wherein the solvent is one or more selected from toluene, dichloromethane, chloroform or tetrahydrofuran. The temperature of the ring-opening polymerization reaction is-40-150 ℃.
Preferably, the ring-opening polymerization reaction is carried out in the presence or absence of a solvent, the temperature of the ring-opening polymerization reaction is 25-100 ℃, and the reaction time is 1-4 h.
Preferably, the ring-opening polymerization reaction is carried out in the presence of a solvent, the temperature of the ring-opening polymerization reaction is 25 ℃, and the reaction time is 1-4 h.
The number average molecular weight of the poly (p-dioxanone) is 500-150000, and the molecular weight distribution is 1.01-15.00.
Preferably, the number average molecular weight of the polydioxanone is 52000-87000, and the molecular weight distribution is 1.02-1.32. Preferably, the molecular weight distribution of the polydioxanone is 1.09-1.25.
The invention realizes the high-efficiency ring-opening polymerization of the PDO monomer by the selection of different types of organic nonmetal catalysts and the regulation and control of an initiator structure.
Compared with the prior art, the invention has the beneficial effects that:
the organic nonmetal catalyst provided by the invention realizes the high-efficiency ring-opening polymerization of the monomer by activating the functional group in the PDO, and the polymerization reaction has the advantages of high activity, easy regulation and mild reaction. The organic nonmetal catalyst provided by the invention overcomes the defects of long reaction time, low conversion rate and low molecular weight of the traditional metal catalytic system, and the obtained PPDO material has the advantages of high molecular weight and narrow distribution.
Drawings
FIG. 1 is a nuclear magnetic spectrum of polydioxanone prepared in example 1;
FIG. 2 is a gel permeation chromatogram of polydioxanone prepared in example 1;
FIG. 3 is a gel permeation chromatogram of polydioxanone prepared in example 13.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be further described in detail with reference to the accompanying drawings and examples. It should be understood that the detailed description and specific examples, while indicating the scope of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.
The organometalloid catalysts used in the following examples are of the formula 1-4:
Figure BDA0002326277120000051
example 1
The operation process is carried out in a glove box under anhydrous and oxygen-free environment, organic nonmetal catalyst 1(0.0250g, 0.05mmol), benzyl alcohol (0.0060g, 0.05mmol), PDO (1.02g, 10mmol) and 1mL toluene are added into a glass reaction bottle with an effective volume of 25mL, and the reaction is carried out for 4 hours at 25 ℃. When the system is completely solidified, adding benzoic acid to quench, adding hot chloroform to dissolve the product, sampling and utilizing1H NMR gave a monomer conversion which was settled in methanol to give PP as a white powderA DO polymer. The catalytic results are shown in table 1, and the nuclear magnetic spectrum and the gel permeation chromatogram are shown in fig. 1 and fig. 2 (abscissa is time, and ordinate is detector signal), respectively.
Example 2
As shown in example 1, PPDO polymer was obtained after 4 hours of reaction under the same conditions using organometalloid catalyst 2, and the catalytic results are shown in Table 1.
Example 3
As shown in example 1, PPDO polymer was obtained after 1 hour of reaction under the same conditions using the organometalloid catalyst 3, and the catalytic results are shown in Table 1.
Example 4
As shown in example 1, PPDO polymer was obtained after 4 hours of reaction under the same conditions using organometalloid catalyst 4, and the catalytic results are shown in Table 1.
Example 5
As shown in example 4, the benzyl alcohol was changed to ethylene glycol under the same conditions, and after 4 hours of reaction, PPDO polymer was obtained, and the catalytic results are shown in Table 1.
Example 6
As shown in example 4, PPDO polymer was obtained after 2 hours of reaction under the same conditions, and the catalytic results are shown in Table 1.
Example 7
As shown in example 6, under the same conditions, the temperature was increased to 60 degrees, and after 2 hours of reaction, PPDO polymer was obtained, and the catalytic results are shown in Table 1.
Example 8
As shown in example 6, under the same conditions, the temperature was increased to 80 degrees, and after 2 hours of reaction, a PPDO polymer was obtained, and the catalytic results are shown in Table 1.
Example 9
As shown in example 6, under the same conditions, the temperature was increased to 100 degrees, and after 2 hours of reaction, a PPDO polymer was obtained, and the catalytic results are shown in Table 1.
Example 10
As shown in example 6, under the same conditions, the temperature was increased to 130 degrees, and after 2 hours of reaction, PPDO polymer was obtained, and the catalytic results are shown in Table 1.
Example 11
As shown in example 6, the solvent was changed to methylene chloride under the same conditions, and after 2 hours of reaction, a PPDO polymer was obtained, and the catalytic results are shown in Table 1.
Example 12
As shown in example 6, the solvent was changed to tetrahydrofuran under the same conditions, and after 2 hours of reaction, a PPDO polymer was obtained, and the catalytic results are shown in Table 1.
Example 13
Under the same conditions, as shown in example 9, without any addition of solvent, the amount of PDO was increased to 2.55 g, and after 4 hours of reaction, a PPDO polymer was obtained, the catalysis results of which are shown in Table 1 and the GPC characterization is shown in FIG. 3.
TABLE 1 test results of polymerization reactions of examples 1 to 13
Figure BDA0002326277120000081
aMnNumber average molecular weight, as determined by gel permeation chromatography;bmolecular weight distribution (PDI) as determined by gel permeation chromatography.
The above-mentioned embodiments are intended to illustrate the technical solutions and advantages of the present invention, and it should be understood that the above-mentioned embodiments are only the most preferred embodiments of the present invention, and are not intended to limit the present invention, and any modifications, additions, equivalents, etc. made within the scope of the principles of the present invention should be included in the scope of the present invention.

Claims (10)

1. An organic nonmetal catalyst for preparing polydioxanone, which is characterized in that the polydioxanone is subjected to ring opening polymerization reaction under the action of the organic nonmetal catalyst and an initiator carrying a hydroxyl structure to obtain the polydioxanone, and the structural formula of the organic nonmetal catalyst is selected from one or more of the following:
Figure FDA0002326277110000011
wherein R is1、R2Each group is independently an aliphatic group or a cyclic group.
2. The organometalloid catalyst for producing polydioxanone according to claim 1, wherein the aliphatic group is selected from methyl, ethyl, isopropyl or n-butyl and the cyclic group is selected from phenyl or cycloalkyl.
3. The organometalloid catalyst for producing polydioxanone according to claim 1, wherein R is1The group is 3, 5-bistrifluoromethylphenyl, R2The group is cycloalkyl or N, N-dimethyl cyclohexylamino, and the structural formula of the organic nonmetal catalyst A is shown as follows:
Figure FDA0002326277110000012
4. the organometalloid catalyst for preparing polydioxanone according to claim 1, wherein the organometalloid catalyst has a structural formula selected from one or more of the following:
Figure FDA0002326277110000021
5. the organometalloid catalyst for preparing polydioxanone according to claim 1, wherein the initiator is selected from one or more of benzyl alcohol BA, ethylene glycol EG, diethylene glycol DEG, 1, 4-butanediol BDO.
6. The organometalloid catalyst for preparing polydioxanone according to claim 1, wherein the ring-opening polymerization reaction is performed under solvent-free conditions at a temperature of 100-160 ℃.
7. The organometalloid catalyst for preparing polydioxanone according to claim 1, wherein the ring-opening polymerization reaction is carried out in the presence of a solvent selected from one or more of toluene, dichloromethane, chloroform or tetrahydrofuran.
8. The organometalloid catalyst for preparing polydioxanone according to claim 7, wherein the temperature of the ring-opening polymerization reaction is-40-150 ℃.
9. The organic nonmetal catalyst for preparing polydioxanone according to claim 1, wherein the polydioxanone has a number average molecular weight of 500-150000 and a molecular weight distribution of 1.01-15.00.
10. The organic nonmetal catalyst for preparing polydioxanone according to claim 1, wherein the polydioxanone has a number average molecular weight of 52000 to 87000 and a molecular weight distribution of 1.02 to 1.32.
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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103288788A (en) * 2013-05-09 2013-09-11 北京师范大学 Delta-valerolactone compounds, preparation method and application
CN103497314A (en) * 2013-10-10 2014-01-08 大连理工大学 Linear comb polycaprolactones and preparation method thereof
US20170197356A1 (en) * 2015-07-23 2017-07-13 Zhejiang University Fabrication and application of shape memory polymer possessing transesterification induced permanent reshaping property
CN107022069A (en) * 2017-04-27 2017-08-08 南京工业大学 A kind of method that utilization bionic catalyst is catalyzed γ valerolactone ring-opening polymerisations
CN107915832A (en) * 2017-10-19 2018-04-17 复旦大学 Material of polycarbonate/polyester containing iodine of X rays development and preparation method and application
CN110305303A (en) * 2019-07-24 2019-10-08 青岛科技大学 A kind of preparation method of degradable biological base polyester of the side chain containing double bond functional group

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103288788A (en) * 2013-05-09 2013-09-11 北京师范大学 Delta-valerolactone compounds, preparation method and application
CN103497314A (en) * 2013-10-10 2014-01-08 大连理工大学 Linear comb polycaprolactones and preparation method thereof
US20170197356A1 (en) * 2015-07-23 2017-07-13 Zhejiang University Fabrication and application of shape memory polymer possessing transesterification induced permanent reshaping property
CN107022069A (en) * 2017-04-27 2017-08-08 南京工业大学 A kind of method that utilization bionic catalyst is catalyzed γ valerolactone ring-opening polymerisations
CN107915832A (en) * 2017-10-19 2018-04-17 复旦大学 Material of polycarbonate/polyester containing iodine of X rays development and preparation method and application
CN110305303A (en) * 2019-07-24 2019-10-08 青岛科技大学 A kind of preparation method of degradable biological base polyester of the side chain containing double bond functional group

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