High-strength bio-based self-repairing polysiloxane-urethane and preparation method thereof
By introducing cystine into the polymer system, a high-strength bio-based self-healing polysiloxane-urethane material was prepared, which solved the problems of difficult recycling and insufficient self-healing performance of cross-linked polyurethane, and achieved the effects of high strength, environmental protection and wide application.
Patent Information
- Application Number
- CN202511422661.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-30
- Publication Date
- 2025-12-12
AI Technical Summary
Cross-linked polyurethane materials are difficult to recycle, and it is difficult to achieve both self-healing and mechanical properties. Furthermore, traditional dynamic bond materials have low strength and cause serious environmental pollution.
By introducing cystine into the polymer system, high-strength bio-based self-healing polysiloxane-urethane materials are prepared through the combined action of disulfide bonds and hydrogen bonds, combining the flexibility and thermal stability of polysiloxane.
It improves the self-healing effect and mechanical properties of the material, enhances its environmental friendliness, expands its application range, and possesses good thermal stability and hydrophobicity.
Smart Images
Figure CN121108445A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of polymer material preparation technology, specifically relating to a high-strength bio-based self-healing polysiloxane-urethane and its preparation method. Background Technology
[0002] Crosslinked polyurethanes possess excellent dimensional stability, mechanical properties, and thermal stability. However, the crosslinked structure of these materials makes recycling extremely difficult. Typically, these polymers are disposed of through incineration or landfill, both of which have a significant environmental impact, leading to environmental problems. Furthermore, commonly used polyurethane synthesis raw materials often utilize petroleum-based feedstocks, which are frequently non-recyclable, further exacerbating environmental pollution.
[0003] This problem can be solved by introducing dynamic bonds, and researchers have explored many such dynamic bonds, including disulfide bonds, borate ester bonds, and hydrogen bonds. However, this leads to a new problem: materials with self-healing capabilities often have low strength. Summary of the Invention
[0004] This invention addresses the shortcomings of existing technologies by introducing cystine into the polymer system, thus solving the problems of traditional cross-linked polyurethanes being difficult to recycle and having both self-healing and mechanical properties.
[0005] This invention provides a high-strength bio-based self-healing polysiloxane-urethane, which is prepared by reacting a dehydrated bifunctional polyol, a bifunctional polydimethylsiloxane, isocyanate, an organotin catalyst, and an organic solvent at 75-85°C for 2-2.5 hours in a nitrogen atmosphere to obtain a viscous transparent polyurethane prepolymer; then, cystine that has been ultrasonically treated for 1 hour and an organic solvent are added and reacted at 40-50°C for 4-6 hours to obtain a viscous white polyurethane; finally, it is poured into a clean mold and cured at 60-70°C for 24-28 hours to obtain a high-strength bio-based self-healing polysiloxane-urethane material.
[0006] Among them, the difunctional polyol is one of polyethylene glycol, polytetrahydrofuran glycol, polycarbonate, polyethylene adipate, polybutylene adipate, polyhexane adipate, or polycaprolactone diol, with Mn=500-5000; the difunctional polydimethylsiloxane is aminopropyl-terminated or hydroxyl-terminated polydimethylsiloxane, with Mn=5000-20000; and the isocyanate is one of isophorone diisocyanate, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, or hexamethylene diisocyanate.
[0007] The molar ratio of the difunctional polyol to the difunctional polydimethylsiloxane is 10:1; the molar ratio of the difunctional polyol to the isocyanate is 5:9; and the amount of organotin catalyst is 0.2-0.5 wt% of the total mass of the difunctional polyol and the difunctional polydimethylsiloxane.
[0008] The molar ratio of bifunctional polydimethylsiloxane to cystine is 1:6.
[0009] The general structural formula of the polysiloxane-urethane prepared by the above method is as follows: , , , , .
[0010] Beneficial effects: This invention introduces cystine into a polyurethane system. The disulfide bonds in cystine possess excellent self-healing properties, while the hydrogen bonds formed by the carboxyl groups not only provide self-healing capabilities but also dissipate energy, enhancing the polymer's mechanical properties. Through the combined effect of disulfide and hydrogen bonds, the self-healing effect of polyurethane is significantly improved. Furthermore, cystine is a bio-based monomer, enabling the degradation of polyurethane, thus giving the material a green and environmentally friendly advantage.
[0011] This invention introduces polysiloxane, in which the silicon-oxygen bonds have high bond energy and good flexibility, which can improve the thermal stability, hydrophobicity, and mechanical properties of the material, and increase the application range of the material. Attached Figure Description
[0012] Figure 1 The infrared spectrum of the high-strength bio-based self-healing polysiloxane-urethane prepared in Example 1 is shown.
[0013] Figure 2 The image shows the self-healing test results of the high-strength bio-based self-healing polysiloxane-urethane prepared in Example 1.
[0014] Figure 3 Thermogravimetric analysis (TGA) results of the high-strength bio-based self-healing polysiloxane-urethane prepared in Example 1 are shown.
[0015] Figure 4 Thermogravimetric analysis (TGA) curve of the high-strength bio-based self-healing polysiloxane-urethane prepared in Comparative Example 3. Detailed Implementation
[0016] The present invention will now be described in detail with reference to specific embodiments.
[0017] Example 1: 10g of polytetrahydrofuran diol (Mn=1000) that has been vacuum dehydrated at 100℃ for 2 hours and 1g of hydroxyl-terminated polydimethylsiloxane were added to a 100ml three-necked flask that had been dried in a forced-air oven and treated with nitrogen. 2.96g of 2,4-toluene diisocyanate dissolved in 10ml of N,N-dimethylformamide and 0.03g of organotin catalyst were added. The mixture was reacted at 80℃ for 2 hours to obtain a viscous isocyanate-terminated polyurethane prepolymer.
[0018] 1g of cystine dissolved in 20ml of N,N-dimethylformamide and sonicated for 1h was added to the polyurethane prepolymer and reacted at 50℃ for 6h to obtain a viscous white polyurethane. The viscous polyurethane was slowly poured into a mold and cured at 60℃ for 12h to obtain a high-strength bio-based self-healing polysiloxane-urethane.
[0019] Infrared analysis showed that the product was at 2250 cm⁻¹ -1 The disappearance of the isocyanate group characteristic peak indicates that the reaction is complete; at 3300 cm⁻¹ -1 The nearby peak is a characteristic peak of -NH, at 650 cm⁻¹. -1 The presence of the characteristic peak of SS indicates the successful introduction of cystine and the successful synthesis of high-strength bio-based self-healing polysiloxane-urethane material.
[0020] To verify the excellent mechanical properties of the material, the tensile strength of the polyurethane was tested using a WDT-3030KN tensile testing machine. Standard specimens were prepared according to the national standard GB-T / 2009, and the tensile strength was measured to be 25.73 MPa and the elongation at break was 1265%.
[0021] To verify the material's excellent self-healing properties, the scratches were fixed in length and then heated at 80°C for 24 hours. Figure 2 It can be seen that the high-strength bio-based self-healing polysiloxane-urethane material significantly reduces the depth of scratches, demonstrating its self-healing function.
[0022] To verify the material's excellent heat resistance, thermogravimetric analysis was conducted at temperatures ranging from 30 to 800°C. The 5% weight loss temperature was 265°C, demonstrating good heat resistance.
[0023] To verify the material's excellent hydrophobicity, a water contact angle test was conducted, with three parallel measurements taken. The measured water contact angle was 112.3°.
[0024] Example 2: 20g of polytetrahydrofuran diol (Mn=2000) that has been vacuum dehydrated at 100℃ for 2 hours and 1g of hydroxyl-terminated polydimethylsiloxane were added to a 100ml three-necked flask that had been dried in a forced-air oven and treated with nitrogen. 2.96g of 2,4-toluene diisocyanate dissolved in 10ml of N,N-dimethylformamide and 0.03g of organotin catalyst were added. The mixture was reacted at 80℃ for 2 hours to obtain a viscous isocyanate-terminated polyurethane prepolymer.
[0025] The high-strength bio-based self-healing polysiloxane-urethane obtained was the same as in Example 1. The tensile strength was measured to be 23.97 MPa, and the elongation at break was 1046%.
[0026] Example 3: 10g of polyethylene glycol (Mn=1000) that has been vacuum dehydrated at 100℃ for 2 hours and 1g of hydroxyl-terminated polydimethylsiloxane were added to a 100ml three-necked flask that had been dried in a forced-air oven and treated with nitrogen. 2.96g of 2,6-toluene diisocyanate dissolved in 10ml of N,N-dimethylformamide and 0.03g of organotin catalyst were added. The mixture was reacted at 80℃ for 2 hours to obtain a viscous isocyanate-terminated polyurethane prepolymer PU-1.
[0027] The high-strength bio-based self-healing polysiloxane-urethane obtained was the same as in Example 1. The tensile strength was measured to be 24.44 MPa, and the elongation at break was 1317%.
[0028] Example 4: 20g of polyethylene glycol (Mn=2000) that has been vacuum dehydrated at 100℃ for 2 hours and 1g of hydroxyl-terminated polydimethylsiloxane were added to a 100ml three-necked flask that had been dried in a forced-air oven and treated with nitrogen. 2.96g of 2,6-toluene diisocyanate dissolved in 10ml of N,N-dimethylformamide and 0.03g of organotin catalyst were added. The mixture was reacted at 80℃ for 2 hours to obtain a viscous isocyanate-terminated polyurethane prepolymer PU-1.
[0029] The high-strength bio-based self-healing polysiloxane-urethane obtained was the same as in Example 1. The tensile strength was measured to be 26.45 MPa, and the elongation at break was 1118%.
[0030] Example 5: 10g of polyethylene adipate (Mn=1000) that has been vacuum dehydrated at 100℃ for 2 hours and 1g of hydroxyl-terminated polydimethylsiloxane were added to a 100ml three-necked flask that had been dried in a forced-air oven and treated with nitrogen. 3.77g of isophorone diisocyanate dissolved in 10ml of N,N-dimethylformamide and 0.03g of organotin catalyst were added. The mixture was reacted at 80℃ for 2 hours to obtain a viscous isocyanate-terminated polyurethane prepolymer PU-1.
[0031] The high-strength bio-based self-healing polysiloxane-urethane obtained was the same as in Example 1. The tensile strength was measured to be 23.98 MPa, and the elongation at break was 1224%.
[0032] Example 6: 20g of polyethylene adipate (Mn=2000) that has been vacuum dehydrated at 100℃ for 2 hours and 1g of hydroxyl-terminated polydimethylsiloxane were added to a 100ml three-necked flask that had been dried in a forced-air oven and treated with nitrogen. 3.77g of isophorone diisocyanate dissolved in 10ml of N,N-dimethylformamide and 0.03g of organotin catalyst were added. The mixture was reacted at 80℃ for 2 hours to obtain a viscous isocyanate-terminated polyurethane prepolymer PU-1.
[0033] The high-strength bio-based self-healing polysiloxane-urethane obtained was the same as in Example 1. The tensile strength was measured to be 25.22 MPa, and the elongation at break was 1237%.
[0034] Example 7: 10g of polybutylene adipate (Mn=1000) that has been vacuum dehydrated at 100°C for 2 hours and 1g of hydroxyl-terminated polydimethylsiloxane were added to a 100ml three-necked flask that had been dried in a forced-air oven and treated with nitrogen. 4.25g of diphenylmethane diisocyanate and 0.03g of organotin catalyst were added, and the mixture was reacted at 80°C for 2 hours to obtain a viscous isocyanate-terminated polyurethane prepolymer PU-1.
[0035] The high-strength bio-based self-healing polysiloxane-urethane obtained was the same as in Example 1. The tensile strength was measured to be 25.04 MPa, and the elongation at break was 1209%.
[0036] Example 8: 20g of polybutylene adipate (Mn=2000) that has been vacuum dehydrated at 100℃ for 2 hours and 1g of hydroxyl-terminated polydimethylsiloxane were added to a 100ml three-necked flask that had been dried in a forced-air oven and treated with nitrogen. 4.25g of diphenylmethane diisocyanate dissolved in 10ml of N,N-dimethylformamide and 0.03g of organotin catalyst were added. The mixture was reacted at 80℃ for 2 hours to obtain a viscous isocyanate-terminated polyurethane prepolymer PU-1.
[0037] The high-strength bio-based self-healing polysiloxane-urethane obtained was the same as in Example 1, with a tensile strength of 23.97 MPa and an elongation at break of 1365%.
[0038] Example 9: 10g of polyhexyl adipate (Mn=1000) that has been vacuum dehydrated at 100°C for 2 hours and 1g of hydroxyl-terminated polydimethylsiloxane were added to a 100ml three-necked flask that had been dried in a forced-air oven and treated with nitrogen. 4.45g of dicyclohexylmethane diisocyanate dissolved in 10ml of N,N-dimethylformamide and 0.03g of organotin catalyst were added. The mixture was reacted at 80°C for 2 hours to obtain a viscous isocyanate-terminated polyurethane prepolymer PU-1.
[0039] The high-strength bio-based self-healing polysiloxane-urethane obtained was the same as in Example 1. The tensile strength was measured to be 24.25 MPa, and the elongation at break was 1149%.
[0040] Example 10: 20g of polyhexyl adipate (Mn=2000) that has been vacuum dehydrated at 100℃ for 2 hours and 1g of hydroxyl-terminated polydimethylsiloxane were added to a 100ml three-necked flask that had been dried in a forced-air oven and treated with nitrogen. 4.45g of dicyclohexylmethane diisocyanate dissolved in 10ml of N,N-dimethylformamide and 0.03g of organotin catalyst were added. The mixture was reacted at 80℃ for 2 hours to obtain a viscous isocyanate-terminated polyurethane prepolymer PU-1.
[0041] The high-strength bio-based self-healing polysiloxane-urethane obtained was the same as in Example 1. The tensile strength was measured to be 22.49 MPa, and the elongation at break was 1148%.
[0042] Example 11: 10g of polycaprolactone diol (Mn=1000) that has been vacuum dehydrated at 100°C for 2 hours and 1g of hydroxyl-terminated polydimethylsiloxane were added to a 100ml three-necked flask that had been dried in a forced-air oven and treated with nitrogen. 2.86g of hexamethylene diisocyanate dissolved in 10ml of N,N-dimethylformamide and 0.03g of organotin catalyst were added. The mixture was reacted at 80°C for 2 hours to obtain a viscous isocyanate-terminated polyurethane prepolymer PU-1.
[0043] The high-strength bio-based self-healing polysiloxane-urethane obtained was the same as in Example 1. The tensile strength was measured to be 27.51 MPa, and the elongation at break was 1048%.
[0044] Example 12: 20g of polycaprolactone diol (Mn=2000) that has been vacuum dehydrated at 100℃ for 2 hours and 1g of hydroxyl-terminated polydimethylsiloxane were added to a 100ml three-necked flask that had been dried in a forced-air oven and treated with nitrogen. 2.86g of hexamethylene diisocyanate dissolved in 10ml of N,N-dimethylformamide and 0.03g of organotin catalyst were added. The mixture was reacted at 80℃ for 2 hours to obtain a viscous isocyanate-terminated polyurethane prepolymer PU-1.
[0045] The high-strength bio-based self-healing polysiloxane-urethane obtained was the same as in Example 1. The tensile strength was measured to be 27.01 MPa, and the elongation at break was 1084%.
[0046] Comparative Example 1: 10g of polytetrahydrofuran diol (Mn=1000) that had been vacuum dehydrated at 100℃ for 2 hours and 1g of hydroxyl-terminated polydimethylsiloxane were added to a 100ml three-necked flask that had been dried in a forced-air oven and treated with nitrogen. 2.44g of isophorone diisocyanate dissolved in 10ml of N,N-dimethylformamide and 0.03g of organotin catalyst were added. The mixture was reacted at 80℃ for 2 hours to obtain a viscous isocyanate-terminated polyurethane prepolymer PU-1. This was slowly poured into a mold and cured at 60℃ for 12 hours to obtain a polysiloxane-urethane material. The tensile strength was measured to be 10.42MPa and the elongation at break was 1745%.
[0047] Comparative Example 2: 10g of polytetrahydrofuran diol (Mn=1000) that has been vacuum dehydrated at 100℃ for 2 hours and 1g of hydroxyl-terminated polydimethylsiloxane were added to a 100ml three-necked flask that had been dried in a forced-air oven and treated with nitrogen. 4.88g of isophorone diisocyanate dissolved in 10ml of N,N-dimethylformamide and 0.03g of organotin catalyst were added. The mixture was reacted at 80℃ for 2 hours to obtain a viscous isocyanate-terminated polyurethane prepolymer PU-1.
[0048] 2g of cystine dissolved in 20ml of N,N-dimethylformamide and sonicated for 1h was added to prepolymer CPU-1 and reacted at 50℃ for 6h to obtain a viscous polyurethane prepolymer CPU-2. The viscous polyurethane CPU-2 was slowly poured into a mold and cured at 60℃ for 12h to obtain polysiloxane-urethane. The tensile strength was measured to be 27.88MPa and the elongation at break was 566%.
[0049] Comparative Example 3: 10g of polytetrahydrofuran diol (Mn=1000) that has been vacuum dehydrated at 100℃ for 2 hours was added to a 100ml three-necked flask that had been dried in a forced-air oven and treated with nitrogen. 2.78g of isophorone diisocyanate dissolved in 10ml of N,N-dimethylformamide and 0.03g of organotin catalyst were added. The mixture was reacted at 80℃ for 2 hours to obtain a viscous isocyanate-terminated polyurethane prepolymer PU-1.
[0050] The high-strength bio-based self-healing polysiloxane-urethane was obtained as in Example 1. The tensile strength was measured to be 8.24 MPa, the elongation at break was 1660%, the 5% weight loss temperature was 233 °C, and the water contact angle was 104.4 °.
[0051] Comparative Example 4: 10g of polytetrahydrofuran diol (Mn=1000) that has been vacuum dehydrated at 100℃ for 2 hours and 2g of hydroxyl-terminated polydimethylsiloxane were added to a 100ml three-necked flask that had been dried in a forced-air oven and treated with nitrogen. 3.20g of isophorone diisocyanate dissolved in 10ml of N,N-dimethylformamide and 0.03g of organotin catalyst were added. The mixture was reacted at 80℃ for 2 hours to obtain a viscous isocyanate-terminated polyurethane prepolymer PU-1.
[0052] 1g of cystine dissolved in 20ml of N,N-dimethylformamide and sonicated for 1h was added to prepolymer CPU-1 and reacted at 50℃ for 6h to obtain viscous polyurethane prepolymer CPU-2. The viscous polyurethane CPU-2 was slowly poured into a mold and cured at 60℃ for 12h to obtain polysiloxane-urethane.
[0053] The high-strength bio-based self-healing polysiloxane-urethane obtained was the same as in Example 1. The tensile strength was measured to be 7.68 MPa, and the elongation at break was 1804%.
Claims
1. A high-strength bio-based self-healing polysiloxane-urethane, characterized in that, The general structural formula of the polysiloxane-urethane is as follows: 。 2. The high-strength bio-based self-healing polysiloxane-urethane as described in claim 1, characterized in that, The preparation method of the polysiloxane-urethane is as follows: First, in a nitrogen atmosphere, a dehydrated bifunctional polyol, a bifunctional polydimethylsiloxane, isocyanate, an organotin catalyst, and an organic solvent are reacted to obtain a viscous transparent polyurethane prepolymer; then, cystine that has been ultrasonically treated for 1 hour and an organic solvent are added to obtain a viscous white polyurethane; finally, it is poured into a clean mold and cured to obtain a high-strength bio-based self-healing polysiloxane-urethane material.
3. The high-strength bio-based self-healing polysiloxane-urethane as described in claim 2, characterized in that, The bifunctional polyol is one of polyethylene glycol, polytetrahydrofuran glycol, polycarbonate, polyethylene adipate, polybutylene adipate, polyhexane adipate, or polycaprolactone diol, with Mn=500-5000.
4. The high-strength bio-based self-healing polysiloxane-urethane as described in claim 2, characterized in that, The bifunctional polydimethylsiloxane is an aminopropyl-terminated polydimethylsiloxane or a hydroxyl-terminated polydimethylsiloxane, with Mn=1000-10000.
5. The high-strength bio-based self-healing polysiloxane-urethane as described in claim 2, characterized in that, The isocyanate is one of isophorone diisocyanate, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, or hexamethylene diisocyanate.
6. The high-strength bio-based self-healing polysiloxane-urethane as described in claim 2, characterized in that, The molar ratio of the difunctional polyol, the difunctional polydimethylsiloxane, and the isocyanate was 10:1:4.5; the viscous transparent polyurethane prepolymer was prepared by reacting at 75~85℃ for 2~2.5h.
7. The high-strength bio-based self-healing polysiloxane-urethane as described in claim 2, characterized in that, The organotin catalyst is dibutyltin dilaurate or stannous octoate, and the amount of organotin catalyst used is 0.2-0.5 wt% of the total mass of the difunctional polyol and the difunctional polydimethylsiloxane.
8. The high-strength bio-based self-healing polysiloxane-urethane as described in claim 2, characterized in that, The molar ratio of bifunctional polydimethylsiloxane to cystine is 1:6; the viscous white polyurethane is prepared by reacting at 40~50℃ for 4~6 hours.
9. The high-strength bio-based self-healing polysiloxane-urethane as described in claim 2, characterized in that, Curing temperature is 60-70℃ for 24-28 hours.