Preparation method for polysiloxane-modified polyurethane material
By grafting polysiloxanes onto polyurethane materials, modified polyurethane materials with excellent heat resistance and weather resistance were prepared, solving the stability problem of polyurethane materials in the biomedical field and realizing a simple and efficient modification process.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- JIANGSU BIODA LIFE SCI CO LTD
- Filing Date
- 2025-06-30
- Publication Date
- 2026-07-02
AI Technical Summary
Existing polyurethane materials suffer from insufficient heat resistance, weather resistance, and biostability in biomedical applications. Furthermore, existing modification methods suffer from poor compatibility, complex processes, or the introduction of side reactions.
A polyurethane film with surface-grafted -NCO groups is formed by reacting a polyurethane film with diisocyanate and polysiloxane under specific conditions through dip coating. The film is then reacted with polysiloxane to prepare a modified polyurethane material with surface-grafted polysiloxane. The stability of polysiloxane is used to improve the heat resistance and weather resistance of polyurethane.
The prepared modified polyurethane material significantly improved heat resistance and weather resistance while maintaining mechanical properties, exhibited stable chemical properties, and degradation tests showed no significant changes in the modified material. The process was simple and pollution-free.
Smart Images
Figure CN2025105307_02072026_PF_FP_ABST
Abstract
Description
A method for preparing polysiloxane-modified polyurethane materials Technical Field
[0001] This invention relates to the field of polymer materials technology, specifically a method for preparing polysiloxane-modified polyurethane materials. Background Technology
[0002] Polyurethane (PU) is a rapidly developing class of polymers in recent years. Its molecular chains are composed of soft and hard segments in a block, graft, or interpenetrating network, with urethane as the basic structural unit. Polyurethane possesses excellent physical properties such as elasticity, toughness, abrasion resistance, and oil resistance, and is widely used in various industrial fields. Furthermore, its good biocompatibility and adaptability make it widely applicable in the biomedical field.
[0003] However, polyurethane materials alone also have drawbacks in terms of heat resistance, weather resistance, and biostability. Specifically, polyurethane has experienced varying degrees of failure when used as a long-term implantable material or a blood-contact material in the human body. This is because physiological conditions catalyze polymer degradation mechanisms, including hydrolysis, environmental stress cracking (ESC), and metal ion oxidation (MIO). The degradation of polyurethane inevitably causes collective damage to implanted devices, which limits its application in the biomedical field.
[0004] Organosilicones are chemically stable, thermally stable, and oxidatively stable. Among them, polysiloxanes have high Si-O bond energy (452 kJ / mol), long bond length, high polarity of Si-O-Si bonds, and a 51% ionization tendency. They have a dipole-induced effect on the hydrocarbon groups attached to the Si atoms, which makes their structure have excellent stability. However, polysiloxanes have poor mechanical properties.
[0005] Chinese patent CN 109337077 A discloses a method for preparing a comb-structured organosilicon-polyurethane copolymer. The method first pre-prepares a single-ended polyhydroxy-terminated phenyl-modified polysiloxane and an amino-terminated polysiloxane, then reacts a polyisocyanate with a polyol and the aforementioned two modified polysiloxanes in sequence, and then obtains a comb-structured organosilicon-polyurethane copolymer that combines the advantages of polyurethane and polysiloxane through chain extension. However, this comb-structured copolymer has poor compatibility and insufficient thermal stability.
[0006] Chinese patent CN 107903369 A discloses a method for preparing organosilicon-polyurethane thermoplastic elastomer. It uses a solubilizer with a special structure to change the characteristics of the hard segment and improves the compatibility between polyorganosiloxane and hard segment by optimizing the preparation process. The resulting organosilicon-polyurethane thermoplastic elastomer product has good mechanical properties. However, the addition of solubilizer may lead to side reactions, thereby reducing the physical and chemical properties of the product.
[0007] Chinese patent CN 115124659 A discloses an organosilicon polyurethane material with high blood compatibility and its preparation method. The organosilicon polyurethane material prepared by this method based on the functionalization reaction of polyaddition and unsaturated double bonds has durable and stable mechanical properties and blood compatibility. However, the preparation process is relatively complex and has high requirements for the process, making it inconvenient to promote. Summary of the Invention
[0008] The purpose of this invention is to provide a method for preparing polysiloxane-modified polyurethane materials. By utilizing the structural and performance characteristics of polysiloxane and polyurethane, polysiloxane-modified polyurethane is prepared to achieve complementary advantages and combine the excellent properties of both, thus solving the problems of easy degradation, insufficient heat resistance, weather resistance, stability, and complex procedures of existing polyurethane materials.
[0009] To achieve the above objectives, the present invention provides the following technical solution:
[0010] The preparation method of polysiloxane-modified polyurethane materials includes the following steps:
[0011] Step 1: After washing the polyurethane particles with anhydrous ethanol and deionized water respectively, the polyurethane particles are thoroughly dried in an oven at 40-55℃. Then, the dried polyurethane particles are dissolved in tetrahydrofuran to form an 8%-15% (w / v) solution. A polyurethane film A with a thickness of 150-300 μm is obtained from the solution by dip coating. Polyurethane film A is washed with anhydrous ethanol and deionized water and then dried at 40-50℃.
[0012] Step 2: Disperse diisocyanate in anhydrous toluene, add catalyst, immerse polyurethane membrane A in diisocyanate-toluene solution, heat to 45-55℃ and react for 2.0-3.5 h to obtain polyurethane membrane B with surface grafted -NCO groups;
[0013] Step 3: Disperse polysiloxane in anhydrous toluene, then place the activated polyurethane membrane B in the polysiloxane-toluene solution and react at 40-50℃ for 20-24 h to obtain a polyurethane membrane C with surface grafted polysiloxane.
[0014] Step 4: Rinse polyurethane membrane C with anhydrous toluene to remove unreacted diisocyanate and polysiloxane; vacuum dry polyurethane membrane C at 40-60℃ for 6.0-8.0 h to obtain polysiloxane modified polyurethane membrane material.
[0015] In the above-mentioned method for preparing polysiloxane-modified polyurethane materials, the diisocyanate in step two includes any one of 1,6-hexamethylene diisocyanate (HDI), 4,4'-diphenylmethane diisocyanate (MDI), and L-lysine diisocyanate (LDI).
[0016] In the above-mentioned method for preparing polysiloxane-modified polyurethane materials, polyurethane A in step one is a material containing urethane groups; or polyurethane A is a polyurethane material that is insoluble in anhydrous toluene or water.
[0017] In the above-mentioned method for preparing polysiloxane-modified polyurethane materials, the catalyst in step two includes triethylamine or dibutylene dilaurate.
[0018] In the above-mentioned method for preparing polysiloxane-modified polyurethane materials, the polysiloxane in step three is a hydroxyl-terminated polysiloxane or an amino-terminated polysiloxane. Beneficial effects
[0019] The beneficial effects of this invention are:
[0020] (1) The modified polyurethane material prepared in this invention grafts polysiloxane into the main chain of polyurethane. The introduced polysiloxane portion endows the main chain of polyurethane with good heat resistance, weather resistance and hydrophobicity, effectively making up for the performance defects of single polyurethane materials. Compared with the unmodified polyurethane material, there is no significant change in mechanical properties, with tensile strength of 42.50-44.87 MPa and elongation at break of 1138.10%-1154.15%; the chemical properties are stable, and the in vitro degradation test results show that the unmodified polyurethane material yellows with age, while the modified polyurethane material shows no significant change.
[0021] (2) The modification method provided by this invention has mild reaction conditions. Compared with the methods in the prior art, this method does not damage the mechanical properties of polyurethane materials, and the overall preparation process is simple and pollution-free. This method is applicable to most polyurethane materials, not limited to membrane materials, and is also applicable to other profile polyurethane materials. Attached Figure Description
[0022] Figure 1 shows the chemical reaction equation of this invention.
[0023] Figure 2 is the infrared absorption spectrum of polyurethane film A-1 in Example 1 of the present invention;
[0024] Figure 3 is the C-1 infrared absorption spectrum of the polysiloxane-modified polyurethane film in Example 1 of the present invention;
[0025] Figure 4 is an EDS image of silicon (Si) on the C-1 surface of the polysiloxane-modified polyurethane film in Example 1 of the present invention.
[0026] Figure 5 shows the appearance images of polyurethane film A-1 (left) and polysiloxane-modified polyurethane film C-1 (right) in Embodiment 1 of the present invention;
[0027] Figure 6 shows the appearance of polyurethane membrane A-1 (left) and polysiloxane-modified polyurethane membrane C-1 (right) after 60 days of in vitro degradation test in Example 1 of the present invention. Detailed Implementation
[0028] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the invention.
[0029] Example 1:
[0030] Referring to Figures 1 to 6, this invention relates to a polyurethane-modified material, obtained through the chemical reaction equation shown in Figure 1. This invention also relates to a method for preparing a polysiloxane-modified polyurethane material, comprising the following steps:
[0031] Step 1: After washing the polyurethane particles containing urethane groups with anhydrous ethanol and deionized water respectively, the polyurethane particles were thoroughly dried in a 40°C oven. Then, the dried polyurethane particles were dissolved in tetrahydrofuran to form an 8% (w / v) solution. A 10 mm × 10 mm thick polyurethane film A-1 with a thickness of 150 μm was obtained from the solution by dip coating. The polyurethane film A-1 was washed with anhydrous ethanol and deionized water and then dried at 50°C.
[0032] Step 2: Place the dried 10 mm × 10 mm polyurethane film A-1 (150 μm thick) into a blue-mouth bottle containing 7.2 mL of 1,6-hexamethylene diisocyanate and 3.4 mL of triethylamine in a 100 mL anhydrous toluene. After sealing, heat the bottle in a water bath to 45 °C and react for 2.5 h. Then remove the film and wash it with anhydrous toluene to obtain film B-1 with -NCO groups grafted on the surface.
[0033] Step 3: Place the activated membrane B-1 in a blue-mouthed bottle containing 12 mL of terminal hydroxyl polydimethylsiloxane and 100 mL of anhydrous toluene. After sealing, heat the bottle in a water bath to 40°C and react for 20 h to obtain polyurethane membrane C-1 with surface grafted polysiloxane.
[0034] Step 4: Wash the polyurethane membrane C-1 three times with anhydrous toluene and purified water, and then vacuum dry it at 40°C for 6.0 h to obtain the dried polyurethane membrane C-1 material with surface grafted polydimethylsiloxane.
[0035] Example 2:
[0036] Step 1: After washing the water-insoluble polyurethane particles with anhydrous ethanol and deionized water respectively, the polyurethane particles were thoroughly dried in a 55°C oven. Then, the dried polyurethane particles were dissolved in tetrahydrofuran to form a 15% (w / v) solution. A polyurethane membrane A-2 with a thickness of 10 mm × 10 mm and a thickness of 250 μm was obtained from the solution by dip coating. The polyurethane membrane A-2 was washed with anhydrous ethanol and deionized water and then dried at 40°C.
[0037] Step 2: The dried 10 mm × 10 mm polyurethane film A-2 (thickness 250 μm) was placed in a blue-mouth bottle containing 8.0 mL of 4,4'-diphenylmethane diisocyanate (MDI) and 3.7 mL of triethylamine in 100 mL of anhydrous toluene. After sealing, the mixture was heated in a water bath to 50 °C and reacted for 2.0 h. The film was then removed and washed with anhydrous toluene to obtain film B-2 with -NCO groups grafted on its surface.
[0038] Step 3: Place the activated membrane B-2 into a blue-mouthed bottle containing 15 mL of terminal hydroxyl polydimethylsiloxane and 100 mL of anhydrous toluene. After sealing, heat the bottle in a water bath to 45°C and react for 24 h to obtain a polyurethane membrane C-2 with surface grafted polysiloxane.
[0039] Step 4: Wash the polyurethane membrane C-2 three times with anhydrous toluene and purified water, and then vacuum dry it at 50°C for 7.0 h to obtain the dried polyurethane membrane C-2 material with surface grafted polydimethylsiloxane.
[0040] Example 3:
[0041] Step 1: After washing the polyurethane particles that are insoluble in anhydrous toluene with anhydrous ethanol and deionized water respectively, the polyurethane particles are thoroughly dried in a 50°C oven. Then, the dried polyurethane particles are dissolved in tetrahydrofuran to form a 10% (w / v) solution. A polyurethane membrane A-3 with a size of 10 mm × 10 mm and a thickness of 300 μm is obtained from the solution by dip coating. The polyurethane membrane A-3 is washed with anhydrous ethanol and deionized water and then dried at 45°C.
[0042] Step 2: The dried 10 mm × 10 mm polyurethane film A-3 (thickness 300 μm) was placed in a blue-mouth bottle containing 7.5 mL L-lysine diisocyanate (LDI) and 3.5 mL dibutyl laurate in 100 mL anhydrous toluene. After sealing, the film was heated to 55 °C in a water bath and reacted for 3.5 h. The film was then removed and washed with anhydrous toluene to obtain film B-3 with -NCO groups grafted on the surface.
[0043] Step 3: Place the activated membrane B-3 into a blue-mouthed bottle containing 20 mL of amino-terminated polydimethylsiloxane and 100 mL of anhydrous toluene. After sealing, heat the bottle in a water bath to 50°C and react for 22 h to obtain a polyurethane membrane C-3 with polysiloxane grafted onto its surface.
[0044] Step 4: Wash the polyurethane membrane C-3 three times with anhydrous toluene and purified water, and then vacuum dry it at 60°C for 8.0 h to obtain the dried polyurethane membrane C-3 material with surface grafted polydimethylsiloxane.
[0045] Performance testing
[0046] The following analytical methods are used in all embodiments unless otherwise stated.
[0047] Infrared Spectroscopy: Fourier Transform Infrared Spectroscopy (FT-IR) was performed on a Great 20 spectrometer from Zhongke Ruijie (Tianjin) Technology Co., Ltd. An appropriate amount of sample was evenly spread on the transmission panel glass, and the sample was pressed firmly using the rotating upper arm for scanning. The scanning range was set to 4000–400 cm⁻¹. -1 The resolution is 4 cm. -1 .
[0048] Mechanical Properties: The mechanical properties of the polyurethane membrane materials were tested using a WDW-5 microcomputer-controlled electronic universal testing machine from Shanghai Hualong Testing Instruments Co., Ltd. Before testing, all samples were dried in a 40℃ oven for 6.0 h to eliminate the influence of moisture on the mechanical properties. The tests were conducted at room temperature with a clamp spacing of 20 mm and a tensile rate of 100 mm / min. The samples were tested in triplicate, and the average value was taken.
[0049] In vitro degradation test: A 10 mm × 10 mm polyurethane membrane was placed in a brown bottle. 10 mL of aging solution was poured into the bottle to completely submerge the membrane. The stability of the sample was evaluated at 37°C. The solution was replaced every 3–4 days. Compared to in vivo oxidative degradation, the in vitro degradation test can accelerate the degradation rate by 15 times.
[0050] The mechanical properties of the polyurethane film and the polysiloxane-modified polyurethane film in Examples 1-3 are shown in Table 1.
[0051] Table 1 Mechanical property parameters of polyurethane membrane materials
[0052] Sample Maximum Force (N) Total Elongation at Break (mm) Maximum Elongation (%) Tensile Strength (MPa) A-1 127.99 241.59 1207.95 46.54 C-1 120.69 223.52 1147.60 43.10 A-2 129.77 242.57 1212.85 53.18 C-2 123.38 230.83 1154.15 44.87 A-3 125.78 236.06 1180.30 48.01 C-3 121.55 227.62 1138.10 42.50
[0053] Figure 2 shows the infrared absorption spectrum of polyurethane film A-1 in Example 1, located at 2932 cm⁻¹. -1 The absorption peak at 1740 cm⁻¹ is the stretching vibration peak of CH₂. -1 The absorption peak at 1245 cm⁻¹ is the stretching vibration peak of C=O; -1 The absorption peak at that point is the stretching vibration peak of CO.
[0054] Figure 3 shows the infrared absorption spectrum of polyurethane film C-1 in Example 1, located in the range of 1000–1100 cm⁻¹. -1 The absorption peak at that point is the stretching vibration peak of Si-O, proving that polysiloxane was successfully grafted into the polyurethane chain segment.
[0055] Figure 4 shows the EDS image of silicon (Si) on the surface of the polysiloxane-modified polyurethane film C-1 in Example 1. The silicon element is aggregated and uniformly distributed on the surface of the modified polyurethane film.
[0056] Figure 5 shows the appearance images of polyurethane film A-1 (left) and polysiloxane-modified polyurethane film C-1 (right) in Example 1. Polyurethane film A-1 appears as a colorless, transparent film, while polysiloxane-modified polyurethane film C-1 appears as a milky white film with low transparency.
[0057] Figure 6 shows the appearance of polyurethane membrane A-1 (left) and polysiloxane-modified polyurethane membrane C-1 (right) after 60 days of in vitro degradation testing in Example 1. As can be seen from the figure, after 60 days of degradation testing, polyurethane membrane A-1 turned yellow, indicating that it had undergone oxidative degradation, causing the membrane to yellow. Polysiloxane-modified polyurethane membrane C-1 showed no significant change in appearance; its surface remained relatively smooth, demonstrating that the modified polyurethane membrane, due to the grafting of polysiloxane, became more robust and less prone to degradation, resulting in significantly improved chemical stability.
[0058] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.
[0059] Type the free content description paragraph for the sequence list here.
Claims
1. A method for producing a polysiloxane-modified polyurethane material, characterized by, Includes the following steps: Step 1: After washing the polyurethane particles with anhydrous ethanol and deionized water respectively, the polyurethane particles are thoroughly dried in an oven at 40-55℃. Then, the dried polyurethane particles are dissolved in tetrahydrofuran to form an 8%-15% (w / v) solution. A polyurethane film A with a thickness of 150-300 μm is obtained from the solution by dip coating. Polyurethane film A is washed with anhydrous ethanol and deionized water and then dried at 40-50℃. Step 2: Disperse diisocyanate in anhydrous toluene, add catalyst, immerse polyurethane membrane A in diisocyanate-toluene solution, heat to 45-55℃ and react for 2.0-3.5 h to obtain polyurethane membrane B with surface grafted -NCO groups; Step 3: Disperse polysiloxane in anhydrous toluene, then place the activated polyurethane membrane B in the polysiloxane-toluene solution and react at 40-50℃ for 20-24 h to obtain a polyurethane membrane C with surface grafted polysiloxane. Step 4: Rinse polyurethane membrane C with anhydrous toluene to remove unreacted diisocyanate and polysiloxane; vacuum dry polyurethane membrane C at 40-60℃ for 6.0-8.0 h to obtain polysiloxane modified polyurethane membrane material.
2. The method for producing a polysiloxane-modified polyurethane material according to claim 1, wherein The diisocyanate in step two includes any one of 1,6-hexamethylene diisocyanate (HDI), 4,4'-diphenylmethane diisocyanate (MDI), and L-lysine diisocyanate (LDI).
3. The method for producing a polysiloxane-modified polyurethane material according to claim 1, wherein In step one, polyurethane A is a material containing urethane groups; or polyurethane A is a polyurethane material that is insoluble in anhydrous toluene or water.
4. The method for producing a polysiloxane-modified polyurethane material according to claim 1, wherein In step two, the catalyst includes triethylamine or dibutylene dilaurate.
5. The method for producing a polysiloxane-modified polyurethane material according to claim 1, wherein In step three, the polysiloxane is a hydroxyl-terminated polysiloxane or an amino-terminated polysiloxane.