Thermoplastic polyamide elastomer, process for its preparation and use thereof

Abstract

The application discloses a thermoplastic polyamide elastomer and a preparation method and application thereof. The molecular structure of the thermoplastic polyamide elastomer comprises hard segments A, linear soft segments B and branched soft segments C. The hard segments A are polyamide hard segments, the linear soft segments B comprise at least one of polyether soft segments and polyester soft segments, and the branched soft segments C comprise at least one of branched polyether soft segments and branched polyester soft segments. The thermoplastic polyamide elastomer has high strength, high elasticity and high toughness, is suitable for being used in fields of sports equipment, medical devices, automobiles, smart wear and aerospace, and has the advantages of simple preparation method, low raw material price, low production cost, large-scale industrial production and application.

Description

Technical Field

[0001] This invention relates to the field of thermoplastic elastomer materials technology, specifically to a thermoplastic polyamide elastomer, its preparation method, and its applications. Background Technology

[0002] Thermoplastic polyamide elastomers (TPAEs) are a class of thermoplastic elastomer materials with polyamide as the hard segment and polyether or polyester as the soft segment. They combine the high strength of polyamides with the high elasticity of elastomers, exhibiting excellent mechanical properties and chemical stability. They have enormous application potential in various fields such as footwear manufacturing, high-performance textiles, medical devices, photovoltaics, automotive manufacturing, smart wearables, and aerospace. However, traditional TPAE materials generally suffer from a trade-off between strength, elasticity, and toughness (i.e., it is difficult to simultaneously achieve high strength, high elasticity, and high toughness). Currently, the main approach is to utilize a multi-mechanism control method combining hydrogen bonding with other crosslinking forms (e.g., thermally reversible chemical crosslinking, metal coordination bonds, etc.) to balance the strength and toughness of TPAEs. However, because thermally reversible crosslinking bonds and metal coordination bonds degrade and lose their effectiveness in the high-temperature synthesis environment (200℃~250℃) of TPAEs, this strategy is very difficult to implement in actual industrial production. In summary, existing TPAE materials still have significant shortcomings and cannot fully meet the growing practical application demands.

[0003] Therefore, developing a TPAE material that combines high strength, high elasticity, and high toughness is of great significance. Summary of the Invention

[0004] The purpose of this invention is to provide a thermoplastic polyamide elastomer, its preparation method, and its application.

[0005] The technical solution adopted in this invention is: A thermoplastic polyamide elastomer has a molecular structure comprising a hard segment A, a linear soft segment B, and a branched soft segment C. The hard segment A is a polyamide hard segment, the linear soft segment B includes at least one of a polyether soft segment and a polyester soft segment, and the branched soft segment C includes at least one of a branched polyether soft segment and a branched polyester soft segment.

[0006] Preferably, the molar ratio of the hard segment A, the straight-chain soft segment B, and the branched soft segment C is 1:0.4-0.8:0.2-0.6.

[0007] More preferably, the molar ratio of the hard segment A, the straight-chain soft segment B, and the branched soft segment C is 1:0.45-0.73:0.26-0.52.

[0008] Preferably, the hard segment A comprises at least one of the following: a polyamide hard segment obtained by polymerization of a linear dicarboxylic acid and a linear diamine, a polyamide hard segment obtained by polymerization of ω-aminocarboxylic acid, and a polyamide hard segment obtained by polymerization of lactam.

[0009] Preferably, the molar ratio of the linear dicarboxylic acid to the linear diamine is 1:0.65 to 0.95.

[0010] More preferably, the molar ratio of the linear dicarboxylic acid to the linear diamine is 1:0.75 to 0.95.

[0011] Preferably, the linear dicarboxylic acid has 4 to 12 carbon atoms.

[0012] Preferably, the linear diamine has 4 to 12 carbon atoms.

[0013] Preferably, the ω-aminocarboxylic acid has 4 to 18 carbon atoms.

[0014] Preferably, the lactam has 6 to 12 carbon atoms.

[0015] Preferably, the polyether soft segment includes at least one of polyether diol and polyether diamine.

[0016] Preferably, the number of methylene groups in the repeating units of the polyether soft segment is 2 to 12.

[0017] Preferably, the number-average molecular weight of the polyether soft segment is 200 g / mol to 10000 g / mol.

[0018] Preferably, the polyester soft segment is at least one of polyester diol and polyester diamine.

[0019] Preferably, the number of methylene groups in the repeating units of the polyester soft segment is 3 to 20.

[0020] Preferably, the number-average molecular weight of the polyester soft segment is 200 g / mol to 10000 g / mol.

[0021] Preferably, the structural formula of the branched soft segment C is as follows: In the formula, R1 is selected from polyethers with 2 to 12 methylene groups in the repeating unit and a number-average molecular weight of 200 g / mol to 10000 g / mol, or polyesters with 3 to 20 methylene groups in the repeating unit and a number-average molecular weight of 200 g / mol to 10000 g / mol; R2 is selected from C2 to C3. 18 alkyl chains or C2-C6 substituents 18 The alkyl chain, the substituents are selected from at least one of amino, hydroxy, amide, imide, urea, nitrile, nitro, chlorine, and fluorine, and F1 is selected from... or .

[0022] Preferably, the thermoplastic polyamide elastomer has a tensile strength of 20 MPa to 80 MPa, an elongation at break of 200% to 1000%, and a fracture toughness of 20 MJ / m. 3 ~300MJ / m 3 .

[0023] Preferably, the dissociation energy of the weak hydrogen bond dynamic network in the soft segment region of the thermoplastic polyamide elastomer is 18.7 kJ / mol to 22.4 kJ / mol, and the dissociation energy of the strong hydrogen bond main network in the hard segment region is 24.3 kJ / mol to 26.8 kJ / mol.

[0024] Preferably, the degree of branching of the thermoplastic polyamide elastomer is 0.15 to 0.35.

[0025] A method for preparing a thermoplastic polyamide elastomer as described above includes the following steps: 1) Preparation of hard segment A and branched soft segment C; 2) Mix hard segment A, linear soft segment B and branched soft segment C and react them to obtain thermoplastic polyamide elastomer.

[0026] Preferably, the hard segment A in step 1) is prepared by a method including the following steps: polymerizing the monomers for synthesizing polyamide hard segments to obtain hard segment A.

[0027] Preferably, the polymerization is carried out at a temperature of 200℃~280℃ and a pressure of 0.02MPa The polymerization was carried out under conditions of 0.10 MPa for a time of 0.5 h to 72 h.

[0028] Preferably, the branched soft segment C in step 1) is prepared by a method comprising the following steps: a) N-hydroxymethylaminomethanol (CAS No.: 7487-32-3) and tetrabutylammonium bromide were dispersed in toluene, anhydrous sodium carbonate was added, and then dibromoalkane was slowly added over 20 min to 60 min. The mixture was then reacted at 50 °C to 90 °C for 6 h to 12 h. After adding hydrogen bonding units, the mixture was reacted for 6 h to 8 h to obtain a branched dihydroxy initiator. b) The monomer, branched dihydroxy initiator and catalyst are mixed evenly and then placed in a protective atmosphere for polymerization to obtain the branched soft segment C.

[0029] Preferably, the dibromoalkane in step a) is one of 1,10-dibromodecane, 1,12-dibromododecane, 1,14-dibromotetradecane, and 1,16-dibromohexadecane.

[0030] Preferably, the hydrogen-bonding unit in step a) is one of aniline, imidazole, guanidine chloride, and p-methylaniline.

[0031] Preferably, the molar ratio of the polymerizing monomer and the branched dihydroxy initiator in step b) is 15 to 80:1.

[0032] Preferably, the polymerization monomer in step b) is one of ethylene oxide, propylene oxide, tetrahydrofuran, ε-caprolactone, δ-valerolactone, and γ-butyrolactone.

[0033] Preferably, the catalyst in step b) is at least one of Zn3[Co(CN)6]2 (a bimetallic cyanide complex catalyst DMC) and stannous octoate.

[0034] Preferably, the reaction in step 2) is carried out at a temperature of 230℃~260℃ and a pressure of 0.01MPa The reaction was carried out under conditions of 0.10 MPa for a time of 2 to 36 hours.

[0035] Applications of the thermoplastic polyamide elastomer described above in the fields of sports equipment, medical devices, automobiles, smart wearables, or aerospace.

[0036] The beneficial effects of the present invention are: the thermoplastic polyamide elastomer of the present invention has high strength, high elasticity and high toughness, and is suitable for use in sports equipment, medical devices, automobiles, smart wearables and aerospace fields. Moreover, its preparation method is simple, the raw materials are inexpensive and the production cost is low, making it suitable for large-scale industrial production and application.

[0037] Specifically: 1) This invention establishes a bilevel hydrogen bond network by introducing side chains containing polar groups into the soft segments, thereby improving the strength and toughness of polyamide elastomers through multilevel energy dissipation, and finally obtaining thermoplastic polyamide elastomers with high strength, high elasticity and high toughness. 2) The preparation method of the thermoplastic polyamide elastomer of the present invention is simple, the raw materials are inexpensive, and the production cost is low, making it suitable for large-scale industrial production and application. Attached Figure Description

[0038] Figure 1 The total reflectance infrared spectra of the thermoplastic polyamide elastomers in Examples 1-4 are shown.

[0039] Figure 2 The tensile stress-strain curves are for the thermoplastic polyamide elastomers of Examples 1-4 and Comparative Examples 1-4.

[0040] Figure 3The figures show the tensile strength and elongation at break test results of the thermoplastic polyamide elastomers of Examples 1-4 and Comparative Examples 1-4.

[0041] Figure 4 The graph shows the notched impact strength and Shore hardness test results of the thermoplastic polyamide elastomers of Examples 1-4 and Comparative Examples 1-4. Detailed Implementation

[0042] The present invention will be further explained and described below with reference to specific embodiments.

[0043] Example 1: A thermoplastic polyamide elastomer, the preparation method of which is as follows: 1) Preparation of bi-terminated carboxyl polyamides and branched polyethers: Preparation of double-terminated carboxyl polyamide: 2.92 kg of adipic acid and 1.74 kg of hexamethylenediamine were added to a reaction vessel, followed by 8 kg of deionized water. The atmosphere inside the reaction vessel was then replaced with nitrogen three times. The mixture was then heated to 200 °C and 1.5 MPa. Water was drained and the pressure was reduced. The temperature was then raised to 250 °C and the pressure was reduced to atmospheric pressure after 45 min. The pressure was then evacuated to -0.02 MPa and the reaction was allowed to proceed for 30 min to obtain double-terminated carboxyl polyamide. Preparation of branched polyethers: a) Add 1.54 kg of N-hydroxymethylaminomethanol, 322 g of tetrabutylammonium bromide and 10.3 kg of toluene to a reaction vessel, then add 1.06 kg of anhydrous sodium carbonate, and then add 6.6 kg of 1,10-dibromodecane dropwise over 30 min. Then react at 50 °C for 6 h, and then add 1.18 kg of aniline and react for another 6 h to obtain a branched dihydroxy initiator. b) Add 1.17 kg of branched dihydroxy initiator and 1.56 g of Zn3[Co(CN)6]2 to the reactor, then replace the atmosphere in the reactor with nitrogen three times, then dehydrate under vacuum at 60 °C for 1 h, then add 9.78 L of ethylene oxide at 100 °C at a feed volume flow rate of 5 mL / min, and react for 10 h to obtain branched polyether; 2) Add 9.8 kg of carboxyl-terminated polyamide, 2.16 kg of polytetrahydrofuran glycol with a number average molecular weight of 1000 g / mol and 1.3 kg of branched polyether to a reactor (the molar ratio of carboxyl-terminated polyamide, polytetrahydrofuran glycol and branched polyether is approximately 1:0.45:0.27), then heat to 230℃, maintain a pressure of -0.01 MPa, and react for 4 h to obtain thermoplastic polyamide elastomer.

[0044] Example 2: A thermoplastic polyamide elastomer, the preparation method of which is as follows: 1) Preparation of bi-terminated carboxyl polyamides and branched polyethers: Preparation of double-terminated carboxyl polyamide: 3.1 kg sebacic acid and 1.96 kg decanediamine were added to a reaction vessel, followed by 8.7 kg of deionized water. The atmosphere inside the reaction vessel was then replaced with nitrogen three times. The mixture was then heated to 220 °C and 1.7 MPa. Water was drained and the pressure was reduced. The temperature was then raised to 260 °C. After 50 min, the pressure was reduced to atmospheric pressure. The pressure was then evacuated to -0.04 MPa and reacted for 45 min to obtain double-terminated carboxyl polyamide. Preparation of branched polyethers: a) Add 1.68 kg of N-hydroxymethylaminomethanol, 334 g of tetrabutylammonium bromide and 10.67 kg of toluene to a reaction vessel, then add 1.21 kg of anhydrous sodium carbonate, and then add 7.05 kg of 1,12-dibromododecane dropwise over 40 min. Then react at 60 °C for 8 h, and then add 1.25 kg of imidazole and react for 7 h to obtain a branched dihydroxy initiator. b) Add 1.57 kg of branched dihydroxy initiator and 1.86 g of Zn3[Co(CN)6]2 to the reactor, then replace the atmosphere in the reactor with nitrogen three times, then dehydrate under vacuum at 80 °C for 1 h, then add 10.52 L of propylene oxide at 110 °C at a feed volume flow rate of 6 mL / min, and react for 12 h to obtain branched polyether; 2) Add 9.36 kg of carboxyl-terminated polyamide, 2.29 kg of polypropylene oxide diamine with a number average molecular weight of 2000 g / mol and 1.66 kg of branched polyether to a reactor (the molar ratio of carboxyl-terminated polyamide, polypropylene oxide diamine and branched polyether is approximately 1:0.52:0.38), then heat to 240℃, maintain the pressure at -0.02 MPa, and react for 6 h to obtain thermoplastic polyamide elastomer.

[0045] Example 3: A thermoplastic polyamide elastomer, the preparation method of which is as follows: 1) Preparation of bi-terminated carboxyl polyamides and branched polyesters: Preparation of carboxyl-terminated polyamide: 2.93 kg of dodecanoic acid and 1.56 kg of decanediamine were added to a reaction vessel, followed by 8.2 kg of deionized water. The atmosphere inside the reaction vessel was then replaced with nitrogen three times. The mixture was then heated to 230 °C and 1.8 MPa. Water was drained and the pressure was reduced. The temperature was then raised to 260 °C and the pressure was reduced to atmospheric pressure after 50 min. The pressure was then evacuated to -0.06 MPa and the reaction was allowed to proceed for 50 min to obtain carboxyl-terminated polyamide. Preparation of branched polyesters: a) Add 1.48 kg of N-hydroxymethylaminomethanol, 327 g of tetrabutylammonium bromide and 10.39 kg of toluene to a reaction vessel, then add 1.16 kg of anhydrous sodium carbonate, and then add 6.96 kg of 1,14-dibromotetradecane dropwise over 50 min. Then react at 70 °C for 8 h, and then add 1.2 kg of guanidine chloride and react for another 8 h to obtain a branched dihydroxy initiator. b) Add 1.46 kg of branched dihydroxy initiator and 1.67 g of stannous octoate to the reactor, then replace the atmosphere in the reactor with nitrogen three times, and then slowly add 10.85 kg of ε-caprolactone at 160 °C. React for 6 h to obtain branched polyester. 2) Add 9.49 kg of carboxyl-terminated polyamide, 2.31 kg of polycaprolactone diol with a number average molecular weight of 600 g / mol and 1.82 kg of branched polyester to a reactor (the molar ratio of carboxyl-terminated polyamide, polycaprolactone diol and branched polyester is approximately 1:0.61:0.48), then heat to 250℃, maintain the pressure at -0.04 MPa, and react for 5 h to obtain thermoplastic polyamide elastomer.

[0046] Example 4: A thermoplastic polyamide elastomer, the preparation method of which is as follows: 1) Preparation of bi-terminated carboxyl polyamides and branched polyesters: Preparation of carboxyl-terminated polyamide: 3.31 kg of dodecanoic acid and 1.87 kg of dodecanediamine were added to a reaction vessel, followed by 8.6 kg of deionized water. The atmosphere inside the reaction vessel was then replaced with nitrogen three times. The mixture was then heated to 240 °C and 1.9 MPa. Water was drained and the pressure was reduced. The temperature was then raised to 250 °C and the pressure was reduced to atmospheric pressure after 60 min. The pressure was then evacuated to -0.08 MPa and the reaction was allowed to proceed for 60 min to obtain carboxyl-terminated polyamide. Preparation of branched polyesters: a) Add 1.54 kg of N-hydroxymethylaminomethanol, 331 g of tetrabutylammonium bromide and 10.45 kg of toluene to a reaction vessel, then add 1.26 kg of anhydrous sodium carbonate, and then add 6.88 kg of 1,16-dibromohexadecane dropwise over 60 min. Then react at 80 °C for 9 h, and then add 1.51 kg of p-methylaniline and react for 7 h to obtain a branched dihydroxy initiator. b) Add 1.76 kg of branched dihydroxy initiator and 1.96 g of stannous octoate to the reactor, then replace the atmosphere in the reactor with nitrogen three times, and then slowly add 9.92 kg of γ-butyrolactone at 180 °C. React for 8 h to obtain branched polyester. 2) Add 9.84 kg of carboxyl-terminated polyamide, 2.47 kg of poly(1,4-butanediol sebacate) diamine with a number average molecular weight of 1500 g / mol and 1.86 kg of branched polyester to a reactor (the molar ratio of carboxyl-terminated polyamide, poly(1,4-butanediol sebacate) diamine and branched polyester is approximately 1:0.73:0.52), then heat to 250 °C, maintain a pressure of -0.05 MPa, and react for 6 h to obtain thermoplastic polyamide elastomer.

[0047] Comparative Example 1: A thermoplastic polyamide elastomer is identical to that in Example 1, except that the "branched polyether" in step 2) is replaced with "polytetrahydrofuran diol with a number average molecular weight of 1000 g / mol" during preparation.

[0048] Comparative Example 2: A thermoplastic polyamide elastomer is identical to that in Example 2, except that the "branched polyether" in step 2) is replaced with "polypropylene oxide diamine with a number average molecular weight of 2000 g / mol" during preparation.

[0049] Comparative Example 3: A thermoplastic polyamide elastomer is identical to that in Example 3, except that the molar amount of "branched polyester" in step 2) is replaced with "polycaprolactone diol with a number average molecular weight of 600 g / mol".

[0050] Comparative Example 4: A thermoplastic polyamide elastomer is identical to that in Example 4, except that the molar amount of "branched polyester" in step 2) is replaced with "poly(1,4-butanediol sebacate diamine) with a number average molecular weight of 1500 g / mol".

[0051] Performance testing: 1) The total reflectance infrared spectra of the thermoplastic polyamide elastomers in Examples 1-4 are as follows: Figure 1 As shown.

[0052] Depend on Figure 1 It can be determined that the wave number is approximately 3300 cm⁻¹. -1 The NH stretching vibration peak at this location has a wavenumber of approximately 1650 cm⁻¹. -1 The C=O stretching vibration peak of the amide I band at this location has a wavenumber of approximately 1540 cm⁻¹. -1 The presence of the amide II band with the characteristic -CONH- peak at the position confirms the successful synthesis of the polyamide hard segment; wavenumbers are approximately 2930 / 2850 cm⁻¹. -1 The -CH2- stretching vibration peak corresponds to the alkyl structure in the molecular chain, with a wavenumber of 1000 cm⁻¹. -1 ~1200cm -1The CO / OCO characteristic peaks in the region confirm the introduction of polyether soft segments or polyester soft segments.

[0053] 2) The tensile stress-strain curves of the thermoplastic polyamide elastomers of Examples 1-4 and Comparative Examples 1-4 are shown below. Figure 2 As shown, the tensile strength and elongation at break test results are as follows: Figure 3 As shown, the notched impact strength and Shore hardness test results are as follows: Figure 4 As shown in the table below, the mechanical properties are summarized in the table below: Table 1 Summary of Mechanical Properties

[0054] Note: Tensile strength and elongation at break: Tested in accordance with "GB / T 1040.1-2006 Determination of tensile properties of plastics - Part 1: General".

[0055] Notched impact strength: Tested in accordance with "GB / T 1043.1-2008 Determination of impact properties of simply supported plastic beams - Part 1: Non-instrumental impact test".

[0056] Shore hardness: The test shall be conducted in accordance with "GB / T 2411-2008 Determination of indentation hardness (Shore hardness) of plastics and hard rubber using a hardness tester".

[0057] Depend on Figures 2-4 As shown in Table 1, the thermoplastic polyamide elastomers of Examples 1-4 (based on a bipolar hydrogen bond network) exhibit significant advantages in tensile strength, elongation at break, and notched impact strength compared to the thermoplastic polyamide elastomers of Comparative Examples 1-4 (without the introduction of branched structures). For example, the thermoplastic polyamide elastomer of Example 1 compared to the thermoplastic polyamide elastomer of Comparative Example 1; the thermoplastic polyamide elastomer of Example 4 compared to the thermoplastic polyamide elastomer of Comparative Example 4. This demonstrates that thermoplastic polyamide elastomers possess high strength, high elasticity, and high toughness.

[0058] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A thermoplastic polyamide elastomer, characterized in that, Its molecular structure includes a hard segment A, a linear soft segment B, and a branched soft segment C; the hard segment A is a polyamide hard segment; the linear soft segment B includes at least one of a polyether soft segment and a polyester soft segment; the branched soft segment C includes at least one of a branched polyether soft segment and a branched polyester soft segment.

2. The thermoplastic polyamide elastomer according to claim 1, characterized in that: The molar ratio of the hard segment A, the straight-chain soft segment B, and the branched soft segment C is 1:0.4-0.8:0.2-0.

6.

3. The thermoplastic polyamide elastomer according to claim 1 or 2, characterized in that: The hard segment A comprises at least one of the following: a polyamide hard segment obtained by polymerization of a linear dicarboxylic acid and a linear diamine, a polyamide hard segment obtained by polymerization of ω-aminocarboxylic acid, and a polyamide hard segment obtained by polymerization of lactam.

4. The thermoplastic polyamide elastomer according to claim 3, characterized in that: The linear dicarboxylic acid has 4 to 12 carbon atoms; and / or, the linear diamine has 4 to 12 carbon atoms; and / or, the ω-aminocarboxylic acid has 4 to 18 carbon atoms; and / or, the lactam has 6 to 12 carbon atoms.

5. The thermoplastic polyamide elastomer according to claim 1 or 2, characterized in that: The polyether soft segment includes at least one of polyether diol and polyether diamine; and / or, the number of methylene groups in the repeating unit of the polyether soft segment is 2 to 12; and / or, the polyester soft segment is at least one of polyester diol and polyester diamine; and / or, the number of methylene groups in the repeating unit of the polyester soft segment is 3 to 20.

6. The thermoplastic polyamide elastomer according to claim 5, characterized in that: The number-average molecular weight of the polyether soft segment is 200 g / mol to 10000 g / mol; and / or, the number-average molecular weight of the polyester soft segment is 200 g / mol to 10000 g / mol.

7. The thermoplastic polyamide elastomer according to claim 1 or 2, characterized in that: The structural formula of the branched soft segment C is as follows: In the formula, R1 is selected from polyethers with 2 to 12 methylene groups in the repeating unit and a number-average molecular weight of 200 g / mol to 10000 g / mol, or polyesters with 3 to 20 methylene groups in the repeating unit and a number-average molecular weight of 200 g / mol to 10000 g / mol; R2 is selected from C2 to C3. 18 alkyl chains or C2-C6 substituents 18 The alkyl chain, the substituents are selected from at least one of amino, hydroxy, amide, imide, urea, nitrile, nitro, chlorine, and fluorine, and F1 is selected from... or .

8. A method for preparing a thermoplastic polyamide elastomer as described in any one of claims 1 to 7, characterized in that, Includes the following steps: 1) Preparation of hard segment A and branched soft segment C; 2) Mix hard segment A, linear soft segment B and branched soft segment C and react them to obtain thermoplastic polyamide elastomer.

9. The preparation method according to claim 8, characterized in that: Step 2) The reaction is carried out at a temperature of 230℃~260℃ and a pressure of 0.01MPa The reaction was carried out under conditions of 0.10 MPa for a time of 2 to 36 hours.

10. The application of a thermoplastic polyamide elastomer as described in any one of claims 1 to 7 in the fields of sports equipment, medical devices, automobiles, smart wearables, or aerospace.

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