Degradable aromatic polyester polymer and synthesis method thereof

Abstract

The invention discloses a degradable aromatic polyester polymer and a synthesis method thereof. Based on an intramolecular autocatalytic degradation mechanism, the degradable aromatic polyester with aliphatic ester as a side group is synthesized through molecular design. Monomers used in the method are aromatic diformyl chloride and dihydric alcohol containing aliphatic ester groups, a selected catalyst is inorganic alkali or organic alkali, and the method is synthesized through solution or melt polycondensation. Different from existing non-degradable aromatic polyester, the aromatic polyester obtained by the invention can be naturally degraded under mild conditions, and is novel environment-friendly polyester.

Description

Technical Field

[0001] The invention relates to the synthesis of a degradable aromatic polyester macromolecule, belongs to the field of macromolecule synthesis, and can be naturally degraded under mild conditions. Background Art

[0002] As environmental problems become increasingly serious, plastic pollution has become a global focus. Traditional polymer materials have brought tremendous pressure to the ecological environment due to their difficulty in degradation. Therefore, the development of degradable materials has become one of the important directions of material science research. Aromatic polyesters have become an important category of degradable polymer materials due to their excellent mechanical properties and thermal stability.

[0003] Aromatic polyesters have good biocompatibility and physical and chemical properties and are suitable for multiple applications, such as packaging materials, medical devices, etc. However, existing aromatic polyesters are often insufficient in degradation performance, resulting in them remaining in the environment for a long time. Therefore, how to improve the biodegradation rate of aromatic polyesters has become a current research hotspot.

[0004] In recent years, researchers have gradually adopted different methods to improve the degradability of aromatic polyesters, including adjusting the structure of polymers and introducing biodegradable monomers. In addition, bio-based polyesters synthesized from renewable resources have also shown good application prospects. These studies not only provide new ideas for solving plastic pollution, but also promote the development of degradable materials.

[0005] There is no catalyst residue in the synthetic products of 2,5-furandicarboxylic acid chloride and tartaric acid esters, and they are theoretically degradable according to their structures. 2,5-furandicarboxylic acid chloride and tartaric acid esters are derived from biomass materials, so the synthetic products have high biomass content, good biocompatibility, and high strength and hardness, so they can be used in biomedical materials such as bone repair, cardiovascular stents, etc.

[0006] The novel degradable aromatic polyester and its synthesis method proposed in the present invention significantly improve its biodegradability while maintaining good physical properties by optimizing the synthesis process and selecting a suitable monomer combination, so as to meet the demand of modern society for environmentally friendly materials. Summary of the invention

[0007] Technical issues:

[0008] The invention relates to a degradable aromatic polyester macromolecule and a synthesis method thereof, aiming to solve the deficiencies of the existing aromatic polyester in terms of biodegradability and application performance.

[0009] Technical solution:

[0010] The invention provides a degradable aromatic polyester macromolecule and a synthesis method thereof.

[0011] The degradable aromatic polyester polymer provided by the present invention has structures as shown in the following formulas Ⅰ, Ⅱ and Ⅲ:

[0012]

[0013]

[0014] The present invention provides a method for synthesizing the degradable aromatic polyester polymer, using aromatic diformyl chloride and propylene glycol propionate as raw materials, and polycondensing under the action of an alkali catalyst to obtain the aromatic polyester. The reaction formula is as follows:

[0015]

[0016] The present invention provides a method for synthesizing the degradable aromatic polyester polymer, using aromatic diformyl chloride and propylene glycol malonate diester as raw materials, and polycondensing under the action of an alkali catalyst to obtain the aromatic polyester. The reaction formula is as follows:

[0017]

[0018] The present invention provides a method for synthesizing the degradable aromatic polyester polymer, using aromatic diformyl chloride and tartaric acid ester as raw materials, and polycondensing under the action of an alkali catalyst to obtain the aromatic polyester. The reaction formula is as follows:

[0019]

[0020] The aromatic dicarboxylic acid chlorides include, but are not limited to, terephthaloyl chloride, 2,5-furan dicarboxylic acid chloride, 2,5-thiophene dicarboxylic acid chloride, 2,6-naphthalene dicarboxylic acid chloride and 4,4'-biphenyl dicarboxylic acid chloride.

[0021] The propylene glycol propionate monomers include but are not limited to methyl bis(hydroxymethyl)propionate, ethyl bis(hydroxymethyl)propionate, propyl bis(hydroxymethyl)propionate, butyl bis(hydroxymethyl)propionate, and isopropyl bis(hydroxymethyl)propionate.

[0022] The propylene glycol-based malonate diester monomers include, but are not limited to, dimethyl bishydroxymethyl malonate, diethyl bishydroxymethyl malonate, dipropyl bishydroxymethyl malonate, dibutyl bishydroxymethyl malonate, and diisopropyl bishydroxymethyl malonate.

[0023] The tartrate monomers include, but are not limited to, dimethyl tartrate, diethyl tartrate, dipropyl tartrate, diisopropyl tartrate, dibutyl tartrate, and diisobutyl tartrate.

[0024] The base catalyst includes but is not limited to inorganic bases such as simple substances, oxides, hydroxides, carbonates (bicarbonates), acetates of alkali metals and alkaline earth metals, and organic bases such as triethylamine, dimethylaminopyridine, 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD), tetramethylguanidine, pyridine, and picoline, and the amount used is 200% of the molar amount of diformyl chloride.

[0025] Furthermore, the molar ratio of the aromatic diformyl chloride to the diol monomer and the molar ratio of the aromatic diformyl chloride to the tartaric acid ester monomer are (1.00-1.1):1.

[0026] Furthermore, the polycondensation reaction time is 1-24h, and the reaction temperature is 0-60°C.

[0027] Furthermore, after the polycondensation reaction is completed, the organic solvent is evaporated using a rotary evaporator, the product is poured into a sufficient amount of deionized water, fully stirred for 2 hours, filtered and retained, and dried in a vacuum oven at 60° C. to constant weight.

[0028] The degradation mechanism of the aromatic polyester prepared by the invention is intramolecular autocatalytic degradation, and the aromatic polyester can be degraded in water environments (acidic, neutral, alkaline, seawater), compost, in vivo and the like, and the degradation conditions are mild. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0030] Figure 1 : is a schematic diagram of the compound of the present invention;

[0031] Figure 2 : It is a schematic diagram of the degradation experiment record of Example 7 and Example 11.

[0032] Figure 3 : It is the NMR spectrum of terephthaloyl chloride-cyanobishydroxymethylmalonate.

[0033] Figure 4 : NMR spectrum of 2,5-furandicarbonyl chloride-diethyl bis(hydroxymethyl)malonate. DETAILED DESCRIPTION

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which the present invention belongs. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0035] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0037] Example 1

[0038] The preparation method of the propylene glycol ester monomer of this embodiment comprises the following steps:

[0039] Weigh 13.4 g of 2,2-bis(hydroxymethyl)propionic acid, add it to 150 mL of methanol, use Amberlyst 15 as the catalyst, react at reflux temperature for 18 h to obtain a colorless liquid, filter the obtained liquid on diatomaceous earth and evaporate it to obtain a pure product, with a yield of 80%.

[0040] Example 2

[0041] The preparation method of propylene glycol malonate diester monomer in this embodiment comprises the following steps:

[0042] Weigh 27.1g of dimethyl malonate, add it to 60mL of formaldehyde solution (37%), then add 2.05g of potassium bicarbonate as a catalyst, stir and react at 0-60℃ for 24h to obtain a colorless transparent liquid; remove excess formaldehyde with saturated ammonium sulfate solution, extract with ether, dry with anhydrous sodium sulfate, filter with suction, retain the filtrate, concentrate with rotary evaporation to obtain a viscous liquid, recrystallize with isopropyl ether to obtain white needle-shaped crystals. The yield is 80%.

[0043] Example 3

[0044] The preparation method of propylene glycol malonate diester monomer in this embodiment comprises the following steps:

[0045] Weigh 33.0g of diethyl malonate, add it to 60mL of formaldehyde solution (37%), then add 2.05g of potassium bicarbonate as a catalyst, stir and react at 0-60℃ for 24h to obtain a colorless transparent liquid; remove excess formaldehyde with saturated ammonium sulfate solution, extract with ether, dry with anhydrous sodium sulfate, filter with suction, retain the filtrate, concentrate with rotary evaporation to obtain a viscous liquid, recrystallize with isopropyl ether to obtain white needle-shaped crystals. The yield is 80%.

[0046] Example 4

[0047] The preparation method of propylene glycol malonate diester monomer in this embodiment comprises the following steps:

[0048] Weigh 38.7g of dipropyl malonate, add it to 60mL of formaldehyde solution (37%), then add 2.05g of potassium bicarbonate as a catalyst, stir and react at 0-60℃ for 24h to obtain a colorless transparent liquid; remove excess formaldehyde with saturated ammonium sulfate solution, extract with ether, dry with anhydrous sodium sulfate, filter with suction, retain the filtrate, concentrate with rotary evaporation to obtain a viscous liquid, recrystallize with isopropyl ether to obtain white needle-shaped crystals. The yield is 80%.

[0049] Example 5

[0050] The preparation method of propylene glycol malonate diester monomer in this embodiment comprises the following steps:

[0051] Weigh 50.3g of dibutyl malonate, add it to 60mL of formaldehyde solution (37%), then add 2.05g of potassium bicarbonate as a catalyst, stir and react at 0-60℃ for 24h to obtain a colorless transparent liquid; remove excess formaldehyde with saturated ammonium sulfate solution, extract with ether, dry with anhydrous sodium sulfate, filter with suction, retain the filtrate, concentrate with rotary evaporation to obtain a viscous liquid, recrystallize with isopropyl ether to obtain white needle-shaped crystals. The yield is 80%.

[0052] Example 6

[0053] The method for synthesizing the aromatic polyester of this embodiment comprises the following steps:

[0054] Weigh 43.1g of terephthaloyl chloride and 43.1g of dimethyl bis(hydroxymethyl)malonate, dissolve in 300ml of dichloromethane, then add 43.5g of triethylamine as a catalyst, stir and react at 0-60°C for 1-24h. After the reaction, use a rotary evaporator to evaporate the organic solvent, pour the product into sufficient deionized water, stir well for 2 hours, filter and retain the filter residue, and dry in a vacuum oven at 60°C to constant weight. Yield 80%.

[0055] Example 7

[0056] The method for synthesizing the aromatic polyester of this embodiment comprises the following steps:

[0057] Weigh 44.5g of terephthaloyl chloride and 48.1g of diethyl bis(hydroxymethyl)malonate, dissolve in 300ml of dichloromethane, then add 43.5g of triethylamine as a catalyst, stir and react at 0-60°C for 1-24h. After the reaction, use a rotary evaporator to evaporate the organic solvent, pour the product into sufficient deionized water, stir well for 2 hours, filter and retain the residue, and dry in a vacuum oven at 60°C to constant weight. Yield 80%.

[0058] exist Figure 1 The resulting product is shown in a.

[0059] exist Figure 3 The H NMR spectrum of the product is shown in

[0060] Example 8

[0061] The method for synthesizing the aromatic polyester of this embodiment comprises the following steps:

[0062] Weigh 44.5g of terephthaloyl chloride and 55.6g of dipropyl bis(hydroxymethyl)malonate, dissolve in 300ml of dichloromethane, then add 43.5g of triethylamine as a catalyst, stir and react at 0-60°C for 1-24h. After the reaction, use a rotary evaporator to evaporate the organic solvent, pour the product into sufficient deionized water, stir well for 2 hours, filter and retain the filter residue, and dry in a vacuum oven at 60°C to constant weight. Yield 80%.

[0063] Example 9

[0064] The method for synthesizing the aromatic polyester of this embodiment comprises the following steps:

[0065] Weigh 44.5g of terephthaloyl chloride and 61.5g of dibutyl bis(hydroxymethyl)malonate, dissolve in 300ml of dichloromethane, then add 43.5g of triethylamine as a catalyst, stir and react at 0-60°C for 1-24h. After the reaction, use a rotary evaporator to evaporate the organic solvent, pour the product into sufficient deionized water, stir well for 2 hours, filter and retain the filter residue, and dry in a vacuum oven at 60°C to constant weight. Yield 80%.

[0066] Example 10

[0067] The method for synthesizing the aromatic polyester of this embodiment comprises the following steps:

[0068] Weigh 21.7g of 2,5-furandicarbonyl chloride and 21.6g of dimethyl bis(hydroxymethyl)malonate, dissolve in 300ml of dichloromethane, then add 23.1g of triethylamine as a catalyst, stir and react at 0-60°C for 1-24h. After the reaction, use a rotary evaporator to evaporate the organic solvent, pour the product into sufficient deionized water, stir well for 2 hours, filter and retain the residue, and dry in a vacuum oven at 60°C to constant weight. Yield 80%.

[0069] Embodiment 11

[0070] The method for synthesizing the aromatic polyester of this embodiment comprises the following steps:

[0071] Weigh 21.7g of 2,5-furandicarbonyl chloride and 24.7g of dimethyl bis(hydroxymethyl)malonate, dissolve in 300ml of dichloromethane, then add 23.1g of triethylamine as a catalyst, stir and react at 0-60°C for 1-24h. After the reaction, use a rotary evaporator to evaporate the organic solvent, pour the product into sufficient deionized water, stir well for 2 hours, filter and retain the residue, and dry in a vacuum oven at 60°C to constant weight. Yield 80%.

[0072] exist Figure 1 The resulting product is shown in b.

[0073] exist Figure 4 The H NMR spectrum of the product is shown in

[0074] The aromatic polyesters obtained in Examples 7 and 11 were subjected to degradation performance tests, and the specific test method is as follows:

[0075] Degradation test method: Take 0.3g of each and dissolve it in a sodium hydrogen phosphate aqueous solution, adjust the pH value to 9, and then place the solution in an oven at 60°C. Then observe and record the aromatic polyester in the solution at regular intervals.

[0076] The degradation performance of the aromatic polyesters obtained in Examples 7 and 11 was tested according to the above test method. The degradation process is shown in Figure 2 As can be seen from the figure, it has been significantly degraded.

[0077] The present application is based on the intramolecular self-catalytic degradation of aromatic polyesters. The self-catalytic degradation of aromatic polyesters is studied for the first time, and the carboxyl groups generated by the first step of molecular decomposition are used to further catalyze and accelerate the degradation reaction.

[0078] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A degradable aromatic polyester polymer, characterized in that: Its structure is shown in the following formulas Ⅰ, Ⅱ and Ⅲ:

2. A method for synthesizing a degradable aromatic polyester polymer, characterized in that: Aromatic diformyl chloride and propylene glycol propionate are used as raw materials, and aromatic polyester is obtained by polycondensation reaction under the action of an alkali catalyst. The reaction formula is as follows: The above compound is prepared by using aromatic diformyl chloride and propylene glycol malonate as raw materials, and polycondensing reaction under the action of alkali catalyst to obtain aromatic polyester, and the reaction formula is as follows: The above-mentioned compound is prepared by using aromatic diformyl chloride and tartaric acid ester as raw materials, and polycondensing reaction under the action of alkaline catalyst to obtain aromatic polyester, and the reaction formula is as follows:

3. The method for synthesizing a degradable aromatic polyester polymer according to claim 2, characterized in that: The aromatic dicarboxylic acid chlorides include, but are not limited to, terephthaloyl chloride, 2,5-furan dicarboxylic acid chloride, 2,5-thiophene dicarboxylic acid chloride, 2,6-naphthalene dicarboxylic acid chloride and 4,4'-biphenyl dicarboxylic acid chloride.

4. The method for synthesizing a degradable aromatic polyester polymer according to claim 2, characterized in that: The propylene glycol propionate monomers include but are not limited to methyl bis(hydroxymethyl)propionate, ethyl bis(hydroxymethyl)propionate, propyl bis(hydroxymethyl)propionate, butyl bis(hydroxymethyl)propionate, and isopropyl bis(hydroxymethyl)propionate.

5. The method for synthesizing a degradable aromatic polyester polymer according to claim 2, characterized in that: The propylene glycol-based malonate diester monomers include, but are not limited to, dimethyl bishydroxymethyl malonate, diethyl bishydroxymethyl malonate, dipropyl bishydroxymethyl malonate, dibutyl bishydroxymethyl malonate, and diisopropyl bishydroxymethyl malonate.

6. The method for synthesizing a degradable aromatic polyester polymer according to claim 2, characterized in that: The tartrate monomers include, but are not limited to, dimethyl tartrate, diethyl tartrate, dipropyl tartrate, diisopropyl tartrate, dibutyl tartrate, and diisobutyl tartrate.

7. The method for synthesizing a degradable aromatic polyester polymer according to claim 2, characterized in that: The base catalyst includes but is not limited to inorganic bases such as simple substances, oxides, hydroxides, carbonates (bicarbonates), acetates of alkali metals and alkaline earth metals, and organic bases such as triethylamine, dimethylaminopyridine, 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD), tetramethylguanidine, pyridine, and picoline, and the amount used is 200% of the molar amount of diformyl chloride.

8. The method for synthesizing a degradable aromatic polyester polymer according to claim 2, characterized in that: The organic solvent includes anhydrous dichloromethane, tetrahydrofuran, dimethylformamide, dimethylacetamide, o-dichlorobenzene, methyl pyrrolidone and the like.

9. The method for synthesizing a degradable aromatic polyester polymer according to claim 2, characterized in that: The molar ratio of the diformyl chloride to the diol monomer and the molar ratio of the diformyl chloride to the tartaric acid ester monomer are both (1.00-1.1):1; the polycondensation reaction time is 1-24h, and the polycondensation reaction temperature is 0-60°C.

10. The method for synthesizing a degradable aromatic polyester polymer according to claim 9, characterized in that: After the polycondensation reaction is completed, the organic solvent is evaporated to dryness using a rotary evaporator, the product is poured into sufficient deionized water, fully stirred for 2 hours, filtered and the filter residue is retained, and dried in a vacuum oven at 60° C. to constant weight.

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