A furan-based dynamic covalent polymer network material, its preparation method and its application

Abstract

This application discloses a furan-based dynamic covalent polymer network material, its preparation method, and its application. The furan-based dynamic covalent polymer network material has the structure shown in Formula III, where m is the number of repeating structural units, ranging from 1 to 100; R1 is selected from C1 to C2. 20 Alkyl or substituted phenyl groups; the substituents of the substituted phenyl groups are selected from at least one of methyl, methoxy, ethyl, fluorine, chlorine, bromine, and iodine; R2 is selected from one of these groups; x is the number of repeating structural units, ranging from 1 to 20. This material exhibits good adhesion, self-healing properties, reprocessability, and shape memory properties.

Description

Technical Field

[0001] This application relates to a furan-based dynamic covalent polymer network material, its preparation method, and its application, belonging to the field of polymer materials technology. Background Technology

[0002] In recent years, various bio-based polymers have been developed to address the environmental problems caused by the depletion of petroleum resources. Biomass-derived 5-hydroxymethylfurfural is considered a promising compound, as it can be converted into various furanyl monomers. Furans undergo a thermally reversible Diels-Alder reaction with maleimide. This reaction can be used to design polymers with a variety of functionalities, such as recyclability, shape memory, and self-healing capabilities. Summary of the Invention

[0003] This application provides a furan-based dynamic covalent polymer network material and its preparation method based on a linear polymer synthesized from biomass-derived bisfuran diol and 2,5-furandicarboxylic acid.

[0004] According to one aspect of this application, a furan-based dynamic covalent polymer network material is provided, with the structure shown in III;

[0005]

[0006] in:

[0007] m is the number of repeating structural units, and its value ranges from 1 to 100;

[0008] R1 is selected from C1 to C1. 20 Alkyl, substituted phenyl; the substituents of the substituted phenyl are selected from at least one of methyl, methoxy, ethyl, fluorine, chlorine, bromine, and iodine;

[0009] R2 is selected from One of them.

[0010] Optionally, x is the number of repeating structural units, ranging from 1 to 20.

[0011] According to another aspect of this application, a method for preparing a furan-based dynamic covalent polymer network material is provided, comprising a mixture of the compound shown in Formula I and the compound shown in Formula II, undergoing a Diels-Alder reaction to obtain the furan-based dynamic covalent polymer network material shown in Formula III;

[0012]

[0013] in:

[0014] m is the number of repeating structural units, and its value ranges from 1 to 100;

[0015] n is the number of repeating structural units, and its value ranges from 1 to 100;

[0016] R1 is selected from C1 to C1. 20 Alkyl, substituted phenyl; the substituents of the substituted phenyl are selected from at least one of methyl, methoxy, fluorine, chlorine, bromine, and iodine;

[0017] R2 is selected from One of them, x is the number of repeating structural units, which ranges from 1 to 20.

[0018] Optionally, the temperature of the Diels-Alder reaction is 30–80°C, and the reaction time is 3–72 h.

[0019] Optionally, R1 is a structural unit corresponding to the compound shown in Formula I, which is prepared by polycondensation reaction of the compound shown in Formula IV with 2,5-furandicarboxylic acid.

[0020]

[0021] in:

[0022] R1 is selected from C1 to C1. 20 Alkyl, substituted phenyl; the substituents of the substituted phenyl are selected from at least one of methyl, methoxy, ethyl, fluorine, chlorine, bromine, and iodine;

[0023] The molar ratio of the compound of Formula IV to the 2,5-furandicarboxylic acid is 1:100 to 100:1.

[0024] Optionally, the compound represented by Formula IV is selected from any one of compound 1, compound 2, compound 3, compound 4, compound 5, compound 6, compound 7, compound 8, compound 9, compound 10, compound 11, and compound 12;

[0025]

[0026]

[0027] Optionally, a mixture containing the compound shown in Formula I and the compound shown in Formula II is hot-pressed into a thin film and reacted to obtain a furan-based dynamic covalent polymer network material.

[0028] Optionally, the molar ratio of the compound shown in Formula I to the compound shown in Formula II is 2:1 to 10:1.

[0029] Optionally, the mixture contains a solvent selected from at least one of chloroform, dichloromethane, N,N-dimethylformamide, tetrahydrofuran, toluene, and N,N-dimethylacetamide.

[0030] Optionally, the hot pressing conditions are as follows: the thickness of the hot pressing plate is 0.1 to 1 mm, the hot pressing temperature is 60 to 180°C, the hot pressing time is 1 to 10 min, and the hot pressing pressure is 0.1 to 10 MPa.

[0031] Optionally, the thickness of the hot-pressed plate is selected from any value among 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, and 1.0mm, or any value between any two of the above.

[0032] Optionally, the temperature of the hot pressing is selected from any value among 60℃, 80℃, 100℃, 120℃, 140℃, 160℃, and 180℃, or any value between any two of the above.

[0033] Optionally, the hot pressing time is selected from any value among 1 min, 3 min, 5 min, 7 min, 9 min, and 10 min, or any value between any two of the above points.

[0034] Optionally, the pressure of the hot pressing is selected from any value among 0.1MPa, 1MPa, 3MPa, 5MPa, 7MPa, 9MPa, and 10MPa, or any value between any two of the above.

[0035] Optionally, the reaction conditions are: a reaction temperature of 30–80°C and a reaction time of 3–72 h.

[0036] Optionally, the reaction temperature is selected from any value among 30℃, 40℃, 50℃, 60℃, 70℃, and 80℃, or any value between any two of the above.

[0037] Optionally, the reaction time is selected from any value among 3h, 7h, 15h, 23h, 31h, 39h, 47h, 55h, 63h, and 72h, or any value between any two of the above points.

[0038] The term "C1-C" used in this invention 20 "Alkyl" refers to a straight-chain or branched alkyl group having 1 to 20 carbon atoms; among which "C2 to C4 alkyl" includes ethyl, n-butyl, isobutyl, etc.

[0039] According to another aspect of this application, the application of furan-based dynamic covalent polymer network materials or furan-based dynamic covalent polymer network materials prepared by the above method in plastic articles is provided.

[0040] The beneficial effects that this application can produce include:

[0041] The present invention involves subjecting a mixture containing a compound of Formula I (furan-based basic polyester) and a compound of Formula II (bismaleimide) to a Diels-Alder reaction to obtain a furan-based dynamic covalent polymer network material of Formula III. This material exhibits excellent adhesive properties, self-healing properties, reprocessability, and shape memory properties. Attached Figure Description

[0042] Figure 1 The graphs show the glass transition temperature of the furan-based dynamic covalent polymer network materials prepared in Examples 1-5 of this application as a function of bismaleimide content.

[0043] Figure 2 The graphs show the tensile strength and tensile stress of the furan-based dynamic covalent polymer network materials prepared in Examples 1-5 of this application as a function of bismaleimide content.

[0044] Figure 3 This is a schematic diagram of the shape memory of the furan-based dynamic covalent polymer network material prepared in Example 3 of this application.

[0045] Figure 4 The following are the Fourier Transform Infrared (FTIR) spectra of the furan-based dynamic covalent polymer network materials prepared in Examples 1-5 of this application.

[0046] Figure 5 The NMR spectra of the furan-based dynamic covalent polymer network materials prepared in Examples 1-5 of this application are shown. Detailed Implementation

[0047] The present application is described in detail below with reference to the embodiments, but the present application is not limited to these embodiments.

[0048] Unless otherwise specified, all raw materials used in the embodiments of this application were purchased through commercial channels.

[0049] In the embodiments of this application, the prepared furan-based dynamic covalent polymer network material was characterized using the following instruments.

[0050] Mechanical properties were determined using an Instron 9965 (Norwood, MA) testing machine. The tensile specimens were 20 mm long, 5 mm wide, and 0.2 mm thick, and the tensile rate was 5 mm / min.

[0051] Adhesion strength was determined using an Instron 9965 (Norwood, MA) testing machine. A 1 cm bond was formed between two parallel glass plates. 2 The polymer sample was stretched at a rate of 5 mm / min.

[0052] Thermal properties were determined using differential scanning calorimetry (DSC) on a TA instrument (DSC2500). Approximately 5 mg of sample was heated from 10 °C to 250 °C at a rate of 10 °C / min under a pure nitrogen stream, and then cooled to 10 °C at a rate of 10 °C / min. The glass transition temperature (Tg) was determined. g The value is calculated based on the midpoint of the glass-rubber transition process from the secondary heating scan (10 to 250°C, 10°C / min).

[0053] FTIR scanning was performed using a Thermofisher Nicolet IS50 in Attenuated Total Reflectance (ATR) mode, with a scanning range from 4000 to 400 cm. -1 .

[0054] NMR was performed using a Bruker Avance III 400 MHz NMR spectrometer in deuterated chloroform solvent at room temperature.

[0055] The synthesis of the compound of formula I in the following examples is referenced in the literature (Yi J, Xu Z, Wu Y, et al. Novel “Rigid to Flexible” Biobased Polyesters Fully Derived from 5-Hydroxymethylfurfural: Promising as Sustainable UV Shielding and Gas Barrier Materials[J]. ACS Sustainable Chemistry & Engineering, 2022, 10(14):4404-4414.).

[0056] The reaction formula of the method described in this invention is as follows:

[0057]

[0058] In this reaction equation:

[0059] R1 is C1~C 20 Alkyl, substituted phenyl; the substituents of the substituted phenyl are selected from at least one of methyl, methoxy, fluorine, chlorine, bromine, and iodine;

[0060] R2 is selected from One of them.

[0061] m is the number of repeating structural units, and its value ranges from 1 to 100;

[0062] n is the number of repeating structural units, and its value ranges from 1 to 100.

[0063] Furan-based linear polyester I and bismaleimide II were reacted via a Diels-Alde reaction to obtain furan-based dynamic covalent polymer network material III. Furan-based linear polyester I is a linear homopolymer of the compound shown in Formula IV (bisfuranamine diol) and 2,5-furandicarboxylic acid, and II is a bismaleimide crosslinking agent.

[0064] Example 1

[0065]

[0066] Furan-based linear polyester (8.3 g, 0.001 mol) as shown in Formula 1 and 4,4'-bismaleimide diphenylmethane (0.18 g, 0.0005 mol) were added to 10 mL of chloroform solvent at a molar ratio of 2:1 and mixed evenly. The mixture was then placed between polytetrafluoroethylene plates with 0.2 mm thick aluminum spacers and hot-pressed at 100 °C for 3 minutes at a pressure of 5 MPa. The formed film was removed and placed in a vacuum oven preheated to 60 °C for 7 hours, and then stored at room temperature to obtain a furan-based dynamic covalent polymer network material, designated as Sample 1#.

[0067] The molecular structure of the furan-based dynamic covalent network material shown in sample 1# was characterized by FTIR and NMR, the mechanical properties were characterized by tensile testing, and the thermal properties were characterized by DSC.

[0068] After testing, the glass transition temperature of furanyl dynamic covalent polymer network material sample 1# was 47℃, the tensile modulus was 529 MPa, and the elongation at break was 5%.

[0069] The surface of sample 1# was scratched, heated at 60°C for 1 minute, and the scratches were observed to have basically disappeared under a microscope.

[0070] Example 2

[0071]

[0072] The furan-based linear polymer (8.3 g, 0.001 mol) shown in Formula 1 and 4,4'-bismaleimide diphenylmethane (0.09 g, 0.00025 mol) were added to 10 mL of chloroform solvent at a molar ratio of 4:1 and mixed evenly. The mixture was then placed between polytetrafluoroethylene plates with 0.2 mm thick aluminum spacers and hot-pressed at 100 °C for 3 minutes at a pressure of 5 MPa. The formed film was removed and placed in a vacuum oven preheated to 60 °C for 7 hours, and then stored at room temperature to obtain a furan-based dynamic covalent polymer network material, designated as Sample 2#.

[0073] The molecular structure of the furan-based dynamic covalent network material shown in sample 2# was characterized by FTIR and NMR, the mechanical properties were characterized by tensile testing, and the thermal properties were characterized by DSC.

[0074] After testing, the glass transition temperature of furanyl dynamic covalent polymer network material sample 2# was 29℃, the tensile modulus was 413 MPa, and the elongation at break was 18%.

[0075] The surface of sample #2 was scratched, heated at 60°C for 1 minute, and the scratches were observed to have largely disappeared under a microscope.

[0076] Example 3

[0077]

[0078] The furan-based linear polymer (8.3 g, 0.001 mol) shown in Formula 1 and 4,4'-bismaleimide diphenylmethane (0.0597 g, 0.00017 mol) were added to 10 mL of chloroform solvent at a molar ratio of 6:1 and mixed evenly. The mixture was then placed between polytetrafluoroethylene plates with 0.2 mm thick aluminum spacers and hot-pressed at 100 °C for 3 minutes at a pressure of 5 MPa. The formed film was removed and placed in a vacuum oven preheated to 60 °C for 7 hours, and then stored at room temperature to obtain a furan-based dynamic covalent polymer network material, designated as sample 3#.

[0079] The molecular structure of the furan-based dynamic covalent network material shown in sample 3# was characterized by FTIR and NMR, the mechanical properties were characterized by tensile testing, and the thermal properties were characterized by DSC.

[0080] After testing, the glass transition temperature of furanyl dynamic covalent polymer network material sample 3# was 23℃, the tensile modulus was 63 MPa, and the elongation at break was 56%.

[0081] The surface of sample #3 was scratched, heated at 60°C for 1 minute, and the scratches were observed to have largely disappeared under a microscope.

[0082] The network polymer material prepared in this embodiment was fixed at 0°C as follows: Figure 3 The temporary shape shown was then heated to 30°C, and the shape almost completely recovered to its initial state, with a shape recovery rate of 98%.

[0083] Example 4

[0084]

[0085] The furan-based linear polymer (8.3 g, 0.001 mol) shown in Formula 1 and 4,4'-bismaleimide diphenylmethane (0.0448 g, 0.000125 mol) were added to 10 mL of chloroform solvent at a molar ratio of 8:1 and mixed evenly. The mixture was then placed between polytetrafluoroethylene plates with 0.2 mm thick aluminum spacers and hot-pressed at 100 °C for 3 minutes at a pressure of 5 MPa. The formed film was removed and placed in a vacuum oven preheated to 60 °C for 7 hours, and then stored at room temperature to obtain the furan-based dynamic covalent polymer network material, designated as sample 4#.

[0086] The molecular structure of the furan-based dynamic covalent network material shown in sample 4# was characterized by FTIR and NMR, the mechanical properties were characterized by tensile testing, and the thermal properties were characterized by DSC.

[0087] After testing, the glass transition temperature of furanyl dynamic covalent polymer network material sample 4# was 20℃, the tensile modulus was 37 MPa, and the elongation at break was 79%.

[0088] The surface of sample #4 was scratched, and after heating at 60°C for 1 minute, the scratches were observed to have largely disappeared under a microscope.

[0089] The network polymer material prepared in this embodiment was fixed at 0°C as follows: Figure 3 The temporary shape shown was then heated to 30°C, and the shape almost completely recovered to its initial state, with a shape recovery rate of 98%.

[0090] Example 5

[0091]

[0092] The furan-based linear polymer (8.3 g, 0.001 mol) shown in Formula 1 and 4,4'-bismaleimide diphenylmethane (0.0358 g, 0.0001 mol) were added to 10 mL of chloroform solvent at a molar ratio of 10:1 and mixed evenly. The mixture was then placed between polytetrafluoroethylene plates with 0.2 mm thick aluminum spacers and hot-pressed at 100 °C for 3 minutes at a pressure of 5 MPa. The formed film was removed and placed in a vacuum oven preheated to 60 °C for 7 hours, and then stored at room temperature to obtain the furan-based dynamic covalent polymer network material, designated as sample 5#.

[0093] The molecular structure of the furan-based dynamic covalent network material shown in sample 5# was characterized by FTIR and NMR, the mechanical and adhesive properties were characterized by tensile testing, and the thermal properties were characterized by DSC.

[0094] After testing, the glass transition temperature of furanyl dynamic covalent polymer network material 5# is 18.8℃, the tensile modulus is 21 MPa, and the elongation at break is 120%.

[0095] The surface of the network polymer material prepared in this embodiment was scratched, heated at 60°C for 1 minute, and the scratches basically disappeared when observed under a microscope.

[0096] The network polymer material prepared in this embodiment can be bonded to two glass plates, and the adhesion strength can reach 3×10⁻⁶. 5 N / m 2 .

[0097] Comparative Example 1

[0098]

[0099] The furan-based linear polymer (8.3 g, 0.001 mol) shown in Formula 1 was placed between polytetrafluoroethylene plates with 0.2 mm thick aluminum spacers and hot-pressed at 100°C for 3 minutes at a pressure of 5 MPa. The formed film was then removed and placed in a vacuum oven preheated to 60°C for 7 hours, and then stored at room temperature to obtain a furan-based dynamic covalent polymer network material, designated as sample 6#.

[0100] The molecular structure of the furan-based linear polymer material shown in sample 6# was characterized by FTIR testing, the mechanical and adhesive properties were characterized by tensile testing, and the thermal properties were characterized by DSC.

[0101] After testing, the glass transition temperature of furan-based linear polymer material 6# is 3℃, the tensile modulus is 30kPa, and the elongation at break is 617%.

[0102] The surface of linear polymer material sample 6# prepared in Comparative Example 1 was scratched, and after heating at 60°C for 1 minute, the scratches did not disappear when observed under a microscope, indicating that the prepared linear polymer material does not have self-healing properties.

[0103] The linear polymer material sample 6# prepared in Comparative Example 1 was fixed in a temporary shape at 0℃ and then heated to 30℃. The shape was not restored, indicating that the prepared linear polymer material has no shape memory properties.

[0104] The linear polymer prepared in Comparative Example 1 was bonded to two glass plates, with an adhesion strength of 1 × 10⁻⁶. 5 N / m 2 .

[0105] According to Examples 1-5 and Comparative Example 1, from Figure 1 It can be seen that with the increase of the amount of bismaleimide added, the tensile strength and elongation at break increase.

[0106] According to Examples 1-5 and Comparative Example 1, from Figure 2 It can be seen that the glass transition temperature increases with the increase of the amount of bismaleimide added.

[0107] According to Examples 3 and 4 and the comparative example, from Figure 3 It can be seen that the furan-based dynamic covalent polymer network materials obtained by furan-based linear polyester and bismaleimide molar ratios of 6:1 and 8:1 have good shape memory properties.

[0108] According to Example 5 and Comparative Example 1, it can be seen that the network polymer bond strength increased by 3 times when 10% bismaleimide was added.

[0109] Therefore, it can be seen that by adjusting the ratio of the compound shown in Formula II (bismaleimide) to the compound shown in Formula I (furan-based linear polyester), the mechanical and thermal properties of furan-based dynamic covalent polymer network materials can be controlled. Furthermore, furan-based dynamic covalent polymer network materials with an appropriate amount of bismaleimide exhibit good shape memory, adhesion, and self-healing properties. This is beneficial for designing bio-based polymers with multiple functions and will have positive implications in terms of safety, environmental protection, and economy.

[0110] The above description is merely a few embodiments of this application and is not intended to limit this application in any way. Although this application discloses preferred embodiments as described above, it is not intended to limit this application. Any changes or modifications made by those skilled in the art without departing from the scope of the technical solution of this application using the disclosed technical content are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A furan-based dynamic covalent polymer network material, characterized in that, It has the structure shown in Formula III; Formula III; in: m is the number of repeating structural units, and its value ranges from 20 to 100; R1 is C1~C 20 alkyl; R2 is .

2. The method for preparing the furan-based dynamic covalent polymer network material according to claim 1, characterized in that, A mixture containing the compound shown in Formula I and the compound shown in Formula II undergoes a Diels-Alder reaction to obtain the furanyl dynamic covalent polymer network material shown in Formula III; Formula I; Formula II; Formula III; in: m is the number of repeating structural units, and its value ranges from 20 to 100; n is the number of repeating structural units, and its value ranges from 20 to 100; R1 is C1~C 20 alkyl; R2 is ; The Diels-Alder reaction is carried out at a temperature of 30-80°C for a time of 3-72 hours.

3. The preparation method according to claim 2, characterized in that, In Formula III, R1 is derived from the structural unit R1 of the compound shown in Formula I, which is prepared by polycondensation reaction of the compound shown in Formula IV with 2,5-furandicarboxylic acid. Formula IV; in: R1 is C1~C 20 alkyl; The molar ratio of the compound of Formula IV to the 2,5-furandicarboxylic acid is 1:100 to 100:

1.

4. The preparation method according to claim 3, characterized in that, The compound shown in Formula IV is selected from any one of the compounds shown in Compound 1, Compound 2, and Compound 3. k≥1 and k≤19; ； 。 5. The preparation method according to claim 2, characterized in that, A mixture containing compounds of Formula I and Formula II is hot-pressed into a thin film and reacted to obtain a furan-based dynamic covalent polymer network material.

6. The preparation method according to claim 2, characterized in that, The molar ratio of the compound shown in Formula I to the compound shown in Formula II is 2:1 to 10:

1.

7. The preparation method according to claim 2, characterized in that, The mixture contains a solvent selected from at least one of chloroform, dichloromethane, N,N-dimethylformamide, tetrahydrofuran, toluene, and N,N-dimethylacetamide.

8. The preparation method according to claim 5, characterized in that, The hot pressing conditions are as follows: the thickness of the hot pressing plate is 0.1~1mm, the hot pressing temperature is 60~180℃, the hot pressing time is 1~10min, and the hot pressing pressure is 0.1~10MPa.

9. The preparation method according to claim 5, characterized in that, The reaction conditions are: reaction temperature of 30~80℃ and reaction time of 3~72h.

10. The application of the furan-based dynamic covalent polymer network material according to claim 1 or the furan-based dynamic covalent polymer network material prepared by the method according to any one of claims 2 to 9 in plastic products.

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