A highly elastic, degradable elastomeric material and methods of making the same

Abstract

The application discloses a kind of high elasticity, degradable elastomer material and preparation method thereof, belong to high polymer material synthesis technical field.Preparation method includes the following steps: first, add diacetylated acetic acid monomer and diamine monomer, then add crosslinking agent, obtain under the catalysis of catalyst by polycondensation;The diacetylated acetic acid monomer has one or more of the following structures: wherein x, y and n each independently represent an integer of 1-8.The beneficial effect: the application obtains high elasticity, degradable elastomer material by the method of polycondensation of diacetylated acetic acid monomer and diamine monomer, and such elastomer material has good strain recovery value (strain recovery value is as high as 80%), good reprocessing performance, good water vapor / oxygen barrier performance and adhesion performance etc., and the material contains degradable group, makes elastomer again synthesis in closed loop cycle system.

Description

Technical Field

[0001] This invention belongs to the field of polymer material synthesis technology, specifically relating to a highly elastic, biodegradable elastomer material and its preparation method. Background Technology

[0002] Elastomers are materials that can return to their original shape after external force is removed; however, not all elastic materials are elastomers. High-performance elastomers are considered a class of strategically important materials with unique high elasticity, playing a crucial role in many emerging fields such as tires, coatings, and flexible electronic devices.

[0003] Introducing cross-linked networks can typically improve the properties of elastomers, such as toughness, load-bearing capacity, and solvent resistance, which is ideal for many demanding applications. However, with permanent cross-linked networks, the mobility of polymer chains is limited, resulting in a loss of remanufacturability. This can usually be overcome by incorporating covalently adaptive networks into the polymer matrix.

[0004] Compared to permanently crosslinked networks, covalently adaptive networks in vitreous bodies have received considerable attention in recent years, offering numerous advantages in polymer reprocessing and durability, including disulfide exchange, Diels-Alder reaction, ester exchange, and borate ester bond exchange.

[0005] Chinese patent application CN110857360A discloses the application of a high-tensile, high-toughness polysiloxane nanocomposite elastomer in biodegradable materials. In this patent, polysiloxane is cross-linked via imine bonds, and carbon nanotubes are added to the matrix to prepare a polysiloxane nanocomposite elastomer with excellent degradation properties. This nanocomposite elastomer can be efficiently degraded in the presence of trifluoroacetic acid, alkoxyamines, and benzaldehyde, and the carbon nanotubes can be completely recycled. However, the preparation process of this elastomer is complex and cumbersome, and the tensile properties and toughness of the elastomer material need further improvement. Summary of the Invention

[0006] The technical problem to be solved by this invention is how to solve the problems of complex preparation process, cumbersome operation and poor performance of existing elastomer materials.

[0007] The present invention solves the above-mentioned technical problems through the following technical means:

[0008] The first aspect of this invention provides a method for preparing a highly elastic, biodegradable elastomer material, comprising the following steps: first adding a diacetylacetic acid monomer and a diamine monomer, then adding a crosslinking agent, and performing polycondensation under the catalysis of a catalyst; wherein the diacetylacetic acid monomer has one or more of the following structures:

[0009] Where x, y, and n each independently represent integers from 1 to 8.

[0010] Beneficial effects: This invention obtains highly elastic and biodegradable elastomer materials through polycondensation of diacetylacetic acid monomer, diamine monomer and crosslinking agent. Such elastomer materials have excellent strain recovery value (up to 80%), good reprocessing performance, good water vapor / oxygen barrier performance and adhesion performance, etc. In addition, the material contains biodegradable groups, which enable the elastomer to be synthesized again in a closed-loop recycling system.

[0011] Preferably, the diamine monomer is one or more diamines containing 6-12 carbons.

[0012] Preferably, the crosslinking agent is tris(2-aminoethyl)amine (TREN).

[0013] Preferably, the catalyst is p-toluenesulfonic acid.

[0014] Preferably, the structure of the diacetoacetic acid monomer is as follows: (M6).

[0015] Preferably, the structure of the diacetoacetic acid monomer is as follows: (H6)

[0016] Preferably, the diamine monomer has the following structure:

[0017] Where z is an integer from 1 to 4.

[0018] Preferably, the structure of the diamine monomer is as follows: (A6)

[0019] Preferably, the reaction includes the following steps: first, add diacetylacetic acid monomer and diamine monomer, then add crosslinking agent, and under a nitrogen atmosphere, using p-toluenesulfonic acid as a catalyst, mechanically stir for 3 hours at 120°C, then vacuum stir for 3 hours, and remove the water generated in the reaction system under reduced pressure to obtain the final product.

[0020] A second aspect of the present invention provides a highly elastic, biodegradable elastomer material prepared by the above-described preparation method.

[0021] The advantages of this invention are:

[0022] 1. This invention obtains a highly elastic and biodegradable elastomer material through polycondensation of diacetylacetic acid monomer and diamine monomer. This type of elastomer material has excellent strain recovery value (up to 80%), good reprocessing performance, good water vapor / oxygen barrier performance and adhesion performance, etc. In addition, the material contains biodegradable groups, which enable the elastomer to be synthesized again in a closed-loop recycling system.

[0023] 2. In practical examples disclosed in this invention, a series of highly elastic and biodegradable elastomers were synthesized using M6, H6, A6, and TREN via polycondensation. The chemical and topological structures were adjusted by varying the feed ratios of different contents. These structural modifications allowed for fine-tuning of thermal and mechanical properties. Due to the introduction of long-chain branches, the elastomers exhibited excellent strain recovery (up to 80%). The prepared samples also demonstrated good reprocessing properties due to the thermally induced binding exchange mechanism within the network.

[0024] 3. Elastomers also exhibit excellent water vapor / oxygen barrier properties and adhesion properties. Under acidic conditions, elastomers are highly degradable of monomers, enabling their resynthesis in closed-loop recycling systems. The synthesis of high-performance elastomers using polycondensation offers the possibility of recyclable polymers. Attached Figure Description

[0025] Figure 1 The above is the 1H NMR spectrum of monomer M6 with diacetoacetic acid group in Example 1 of this invention;

[0026] Figure 2 The above is the 1H NMR spectrum of monomer H6 with diacetoacetic acid group in Example 2 of this invention;

[0027] Figure 3 The image shows the carbon NMR spectrum of monomer H6 with diacetoacetic acid group in Example 2 of this invention.

[0028] Figure 4 Mechanical test diagrams of the highly elastic, biodegradable elastomeric polymer materials prepared in Examples 3-8 of this invention;

[0029] Figure 5 These are test graphs showing the oxygen permeability and water vapor permeability of the elastomer materials in Examples 3 and 5 of the present invention.

[0030] Figure 6 This refers to the degradation of the elastomeric polymer in Example 3 of the present invention;

[0031] Figure 7 This study investigates the reprocessability of the elastomer in Example 5 of the present invention.

[0032] Figure 8 The infrared and hydrogen nuclear magnetic resonance (HMR) spectra of the elastomer material in Example 5 of this invention are shown below.

[0033] Figure 9 This is a thermal performance diagram of the prepared sample determined by DSC and TGA in an embodiment of the present invention. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] The present invention does not limit the source of the above-mentioned compounds. They can be commercially available or monomers that can be prepared by simple methods. The present invention does not limit the source of the compounds.

[0036] Example 1:

[0037] The preparation process of monomer M6 (when x=1) with diacetoacetic acid group is as follows:

[0038]

[0039] 1,6-Hexanediol (10.0 g, 85 mmol), tert-butyl acetoacetate (53.5 g, 338 mmol), and toluene (100 mL) were weighed into a 500 mL round-bottom flask equipped with a spherical condenser. The mixture was reacted at 140 °C for 24 h to remove water, and the tert-butyl acetoacetate / toluene azeotrope was distilled off. After the reaction was complete, the mixture was concentrated under vacuum to remove the remaining volatiles. Then, the mixture was purified by chromatographic chromatography with a stepwise mixture of petroleum ether and ethyl acetate to give a colorless oily product (M6) (23.1 g, 95% yield).

[0040] Then, the monomer M6 obtained in Example 1 was analyzed by proton nuclear magnetic resonance (NMR) spectrum analysis. The specific analysis and test results are as follows: Figure 1 As shown.

[0041] 1 H NMR (400MHz, CDCl3) δ4.10 (t, J = 6.7Hz, 4H), 3.43 (s, 4H), 2.24 (s, 6H), 1.63 (s, 4H), 1.35 (s, 4H).

[0042] Example 2:

[0043] The preparation process of the monomer H6 (n=2, y=1) with diacetylacetic acid group is as follows:

[0044]

[0045] Under a nitrogen atmosphere, diacetyl acetate (M6) (7.15 g, 25 mmol) was dissolved in 100 mL of dry tetrahydrofuran. Diisopropylaminolithium (56.25 mL, 2.0 M n-hexane solution, 112.5 mmol) was added dropwise, and the mixture was stirred at 0 °C for 2 h. Then, a tetrahydrofuran solution of 1-iodopentane (8.16 mL, 62.5 mmol) was added dropwise. The mixture was stirred at room temperature for 12 h. After quenching the reaction, the tetrahydrofuran was removed by vacuum concentration. The crude product was dissolved in dichloromethane and hydrolyzed with 2 M hydrochloric acid. After dichloromethane / water extraction, the product was purified by column chromatography using a stepwise mixture of petroleum ether and ethyl acetate to give a pale yellow solid product (H6) (7.7 g, 72% yield).

[0046] Then, the monomer H6 prepared by the method in Example 2 was analyzed by proton nuclear magnetic resonance (NMR) spectrum. The specific analysis and test results are as follows: Figure 2-3 As shown.

[0047] 1 H NMR (400MHz, CDCl3) δ4.08 (t, J = 6.6 Hz, 4H), 3.40 (s, 4H), 2.49 (t, J = 7.4 Hz, 4H), 1.56 (m, 8H), 1.34 (s, 4H), 1.24 (s, 12H), 0.83 (t, J = 6.7 Hz, 6H).

[0048] 13 C NMR (101MHz, CDCl3) δ203.01(s), 167.36(s), 65.20(s), 49.24(s), 43.09(s), 31.54(s), 28.68(s), 28.35(s), 25.45(s), 23.42(s), 14.03(s).

[0049] Example 3

[0050] A method for preparing a highly elastic and biodegradable elastomer material includes the following steps: mixing raw materials M6, A6 and TREN in a molar ratio of 10:9:1, using p-toluenesulfonic acid as a catalyst (5 mol%) under a nitrogen atmosphere, mechanically stirring for 3 h at 120 °C, vacuum stirring for 3 h, and removing water generated in the reaction system under reduced pressure to obtain elastomer material Sample 1.

[0051] Example 4:

[0052] The difference between this embodiment and Embodiment 3 is that the molar ratio of raw materials M6, A6, and TREN is changed from "10:9:1" to "10:8:2", while the other steps are the same as in Embodiment 3. The resulting elastomer material is Sample 2.

[0053] Example 5:

[0054] The difference between this embodiment and Embodiment 3 is that "raw materials M6, A6 and TREN are mixed in a molar ratio of 10:9:1" is changed to "raw materials M6, H6, A6 and TREN are mixed in a molar ratio of 9.8:0.2:9:1". The other steps are the same as in Embodiment 3. The resulting elastomer material is Sample 3.

[0055] Example 6:

[0056] The difference between this embodiment and Embodiment 3 is that the phrase "mixing raw materials M6, A6, and TREN in a molar ratio of 10:9:1" is changed to "mixing raw materials M6, H6, A6, and TREN in a molar ratio of 9.8:0.2:8:2". The other steps are the same as in Embodiment 3. The resulting elastomer material is Sample 4.

[0057] Example 7:

[0058] The difference between this embodiment and Embodiment 3 is that "raw materials M6, A6 and TREN are mixed in a molar ratio of 10:9:1" is changed to "raw materials M6, H6, A6 and TREN are mixed in a molar ratio of 9.5:0.5:9:1". The other steps are the same as in Embodiment 3. The resulting elastomer material is Sample 5.

[0059] Example 8:

[0060] The difference between this embodiment and Embodiment 3 is that the phrase "mixing raw materials M6, A6, and TREN in a molar ratio of 10:9:1" is changed to "mixing raw materials M6, H6, A6, and TREN in a molar ratio of 9.5:0.5:8:2". The other steps are the same as in Embodiment 3. The resulting elastomer material is Sample 6.

[0061] The glass transition temperature, thermal decomposition temperature, and other parameters of the elastomer materials Samples 1-6 obtained in Examples 3-8 are shown in Table 1 below:

[0062] Table 1: Parameters of Synthetic Elastomer Materials Samples 1-6 a

[0063]

[0064]

[0065] Aggregation conditions a Temperature: 120℃, catalyst: PTSA (5mol%), time: 6h. b The glass transition temperature was determined using a differential scanning calorimeter. c Thermal decomposition temperature, thermal degradation temperature at which 5% mass loss occurs (TGA determination).

[0066] Example 9:

[0067] Mechanical testing of highly elastic, biodegradable elastomeric polymer materials

[0068] According to the standard test method ASTM 638, dumbbell-shaped specimens with a length of 28 mm, a width of 2 mm (at the narrowest point), and a thickness of 0.6 mm were used. Stress-strain tests were conducted at room temperature at a speed of 10 mm / min, and at least three specimens of each type were tested.

[0069] Specific test results are as follows: Figure 4 As shown.

[0070] from Figure 4 As can be seen, the polymer sample Sample 1, obtained by adding one-tenth of the crosslinking agent, has a tensile strength as high as 11.8 MPa and an elongation at break of 570%. Figure 4 a) Toughness is 24.8 MJ / m 3 As the proportion of TREN increases, the polymer's mechanical properties reach 20 MPa, and its elongation at break reaches 470%. Figure 4 a) Maximum toughness is 31.4 MJ / m 3 The introduction of H6 resulted in a decrease in tensile strength, which may be due to the polymer matrix ( Figure 4 The polymer added in b) had a lower degree of crystallinity, and a similar trend was observed when the feed ratio of H6 was increased. Figure 4 c). Furthermore, to investigate elastic recovery properties, cyclic stress-strain measurements were performed on the polymer samples, with each sample extended to 300% strain over 10 cycles. Strain recovery (SR) is an important parameter for evaluating elasticity; a high value indicates high elasticity. Figure 4 di.

[0071] Example 10:

[0072] Oxygen and water vapor permeability tests of elastomer materials Sample 1 and Sample 3

[0073] Water vapor transmission rate (WVTR): Measured in a permeation cell at 25°C according to ASTM E96-95. The cell is made of polytetrafluoroethylene (PTFE), partially filled with water, with a polymer membrane placed on top of it sealed. Measurements were performed in a Labthink W3 / 010 balance with 10⁻⁵ g readability, and mass loss was recorded in a computer. The reported value is the average of at least four measurements. Oxygen permeation rate (OP): Measured using a Labthink Basic201 apparatus at 1 atm, 23°C, and 0% relative humidity according to GB / T 1038-2000. The reported value is the average of at least four measurements.

[0074] The results are as follows Figure 5 As shown, from Figure 5 As can be seen, the prepared elastomer has moderate water vapor permeability, with a water vapor transmission rate of 16.3 g mm m. -2 day -1 (Sample 1), 20.8g mm m -2 day -1 (Sample 3). In addition, the elastomer has good oxygen barrier properties, with barrier coefficients of 0.17 and 0.19 Barrer, respectively.

[0075] Example 11:

[0076] Degradation of elastomer polymer Sample 1

[0077] In the acid treatment, a mixture of polymer (1 g), concentrated hydrochloric acid solution (0.4 ml), and tetrahydrofuran (40 ml) was refluxed and stirred at 80 °C for 8 h. The mixture was concentrated, dissolved in dichloromethane, neutralized to neutral with saturated sodium bicarbonate aqueous solution, extracted with dichloromethane, dried with anhydrous sodium sulfate, concentrated, and the degradation product, namely monomer M6, was separated. The recovered monomer can be reintroduced into the elastomer through polycondensation.

[0078] The result is Figure 6 It can be seen that the NMR of the degraded polymer is the same as that of the monomer M6, which proves that the elastomer polymer is degradable.

[0079] Example 12:

[0080] Reprocessing Research

[0081] The reprocessing properties of these elastomer materials can be attributed to the thermally induced bonding exchange mechanism within the network. To investigate reprocessability, elastomer Sample 3 was repeatedly sliced ​​into chips and then compressed several times at 120°C and 5 MPa for 6 minutes. Tensile tests were performed on the post-processed elastomers, and their stress-strain curves were obtained.

[0082] The results are as follows Figure 7 As shown, from Figure 7 As can be seen, compared with the original elastomer, the tensile strength of the regenerated sample increased slightly (10.2 vs 8.3 vs 7.3 MPa), while the elongation at break decreased (340% vs 410% vs 430%). The cyclic stress-strain curves show a decrease in elasticity after two reprocessings (strain recovery, 73% vs 80%).

[0083] Figure 8 The infrared and hydrogen nuclear magnetic resonance (HMR) spectra of the elastomer material in Example 5 of this invention are shown below.

[0084] Figure 9 This is a thermal performance diagram of the prepared sample determined by DSC and TGA in an embodiment of the present invention.

[0085] Example 13:

[0086] The difference between this embodiment and Embodiment 3 is that the raw material M6 is changed to " "x is one of 2-8", and the other steps are the same as in Example 3.

[0087] Example 14:

[0088] The difference between this embodiment and Embodiment 5 is that the raw material M6 is changed to " "x takes any integer from 2 to 8", and change raw material H6 to " "y takes any integer from 2 to 8, and n takes any integer from 1 or 3 to 8". Change A6 to " "z takes any integer from 2 to 4", and the rest is the same as in Example 5.

[0089] The elastomer material prepared in Example 13 has similar properties to the elastomer material Sample 1 prepared in Example 3;

[0090] The elastomer material prepared in Example 14 has similar properties to the elastomer material Sample 3 prepared in Example 5.

[0091] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing a highly elastic, biodegradable elastomer material, characterized in that, Includes the following steps: First, diacetylacetic acid monomer and diamine monomer are added, followed by a crosslinking agent, and then polycondensation is carried out under the catalysis of a catalyst to obtain the product; the diacetylacetic acid monomer has one or more of the following structures: , , where x, y, and n each independently represent integers from 1 to 8; The diamine monomer has the following structure: , where z is an integer from 1 to 4; The crosslinking agent is tris(2-aminoethyl)amine; The molar ratio of M, H, diamine monomer, and crosslinking agent is one of 10:0:9:1, 10:0:8:2, 9.8:0.2:9:1, 9.8:0.2:8:2, 9.5:0.5:9:1, or 9.5:0.5:8:

2.

2. The preparation method according to claim 1, characterized in that, The molar ratio of M, diamine monomer, and crosslinking agent is one of 10:9:1 or 10:8:

2.

3. The preparation method according to claim 1, characterized in that, The molar ratio of M, H, diamine monomer, and crosslinking agent is one of 9.8:0.2:9:1, 9.8:0.2:8:2, 9.5:0.5:9:1, or 9.5:0.5:8:

2.

4. The preparation method according to claim 1, characterized in that, The catalyst is p-toluenesulfonic acid.

5. The preparation method according to claim 1, characterized in that, The structure of the diacetylacetic acid monomer is as follows: 。 6. The preparation method according to claim 1, characterized in that, The structure of the diacetylacetic acid monomer is as follows: 。 7. The preparation method according to claim 1, characterized in that, The diamine monomer has the following structure: , where z is an integer between 2 and 4.

8. The preparation method according to claim 1, characterized in that, The structure of the diamine monomer is as follows: 。 9. The preparation method according to claim 1, characterized in that, The process includes the following steps: first, add diacetylacetic acid monomer and diamine monomer, then add crosslinking agent, and under a nitrogen atmosphere, using p-toluenesulfonic acid as a catalyst, mechanically stir for 3 h at 120 °C, then vacuum stir for 3 h, and remove the water generated in the reaction system under reduced pressure to obtain the final product.

10. A highly elastic, biodegradable elastomer material prepared by any one of claims 1-9.

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