A polysiloxane type polyurethane and a preparation method, device and use thereof

Abstract

The present application relates to a kind of polysiloxane type polyurethane and preparation method, device and purposes.The polysiloxane type polyurethane is made of soft segment and hard segment, and soft segment is mixed soft segment, including the glycol of polycarbonate-polar polydimethylsiloxane-polycarbonate structure ternary copolymer and polycarbonate diol;The chain length ratio of the polycarbonate diol and the ternary copolymer diol is (0.5~1):(2~5), and the mass ratio of the two is (1~2):(8~9);The polysiloxane type polyurethane has polydispersity molecular weight distribution, and its molecular weight distribution is 2.5~4.0.The polysiloxane type polyurethane of application, by its unique soft segment polarization and structural design, molecular weight wide distribution layout, mixed soft segment chain length ratio control, the introduction of silicon-containing chain extender and chain extension system optimization and other multidimensional technical features Synergistic combination, produces significantly exceeds the synergistic effect of the person skilled in the art.

Description

Technical Field

[0001] This invention relates to the field of biomedical materials development and application, specifically to a polysiloxane-type polyurethane applicable to heart valves and its preparation method. Background Technology

[0002] Polyurethane (PU), a copolymer formed by the stepwise polymerization of polyols and polyisocyanates, has become one of the core materials in the medical device field due to its highly designable molecular chains and wide range of tunable properties. Its unique soft-segment-hard-segment microphase separation structure endows the material with a continuous spectrum of properties ranging from flexible to rigid, demonstrating irreplaceable application value in artificial heart valves, vascular stent coatings, orthopedic fillers, and wound dressings. Current performance regulation of polyurethane materials mainly revolves around the following single-dimensional or dual-dimensional goals. For example, some studies improve the compatibility of materials with body fluids and reduce the risk of protein adsorption and cell adhesion by introducing polyether polyols (such as polytetrahydrofuran PTMEG) or grafting hydrophilic groups (such as PEG) onto the surface (e.g., PU coatings for blood-contact devices). However, such materials often suffer from insufficient mechanical strength (e.g., tensile strength <10 MPa) due to excessive molecular chain flexibility, or accelerated hydrolytic degradation due to an excessively high proportion of soft segments, leading to structural failure after long-term implantation.

[0003] To improve in vivo aging resistance, researchers often use aromatic isocyanates (such as MDI) to replace aliphatic isocyanates (such as HDI) to increase hard segment crystallinity, or introduce fluorinated groups to enhance hydrophobicity and chemical inertness (e.g., PU used in artificial joint linings). However, aromatic PU has poor light stability (prone to yellowing and the production of toxic products), and high crystallinity sacrifices the material's elastic recovery rate (elongation at break <200%), making it unsuitable for applications requiring repeated deformation in cardiovascular devices; fluorination modification may disrupt molecular chain regularity, thus reducing tear resistance (tear strength <50 kN / m).

[0004] For high-stress load scenarios, some solutions improve the fracture energy of materials by increasing the content of hard segments (such as increasing the MDI ratio) or introducing nanofillers (such as carbon nanotubes and nano-hydroxyapatite). However, excessive hard segments can lead to increased brittleness of the material (impact strength decreases by more than 30%), and the agglomeration effect of nanofillers can easily cause local stress concentration, which can reduce long-term service reliability. In addition, insufficient interfacial bonding between the filler and the matrix may accelerate interfacial delamination, further weakening the overall stability.

[0005] To match the soft tissue modulus, existing technologies often achieve a balance between low modulus (<10 MPa) and moderate strength (tensile strength 5-15 MPa) by adjusting the molecular weight of the soft segments (e.g., reducing the molecular weight of PTMEG to below 1000 Da). However, this design often comes at the cost of long-term stability—short-chain soft segments are more susceptible to water molecule penetration, leading to chain breakage and degradation, and may show significant swelling or mechanical property degradation (modulus decrease >40%) 6 months after implantation.

[0006] To achieve precise construction of porous structures (such as drug-release scaffolds and tissue-engineered scaffolds), researchers have developed techniques such as phase separation-induced foaming and electrospinning to control pore size distribution (50-500 μm). However, these processes often fail to simultaneously consider biocompatibility (e.g., residual solvents or pore-forming agents may cause inflammation), tear resistance (large-pore structures are prone to crack propagation), and long-term stability (thin pore walls are susceptible to erosion by body fluids). In practical applications, structural collapse or functional failure often occurs.

[0007] In summary, the current preparation logic for polyurethane materials largely follows a "single-point breakthrough" approach, that is, targeted optimization of a specific property (such as biocompatibility or mechanical strength). This "specialized" performance design leads to multiple contradictions in practical applications: for example, high biocompatibility may be accompanied by rapid degradation, high strength may sacrifice toughness, and structural controllability may introduce toxicity risks. Therefore, developing a method for preparing polyurethane materials that can systematically integrate multiple core properties has become a key technological bottleneck driving the upgrade of high-end medical devices. Summary of the Invention

[0008] The purpose of this invention is to provide a polysiloxane-based polyurethane that incorporates multi-dimensional technical features in a synergistic combination to produce unexpected synergistic effects in terms of biocompatibility, long-term stability, tear resistance, mechanical property balance, and structural controllability, thereby achieving simultaneous improvement in multiple properties.

[0009] In one aspect, the present invention provides a polysiloxane-type polyurethane, comprising soft segments and hard segments, wherein the soft segments are a mixture of soft segments, including a terpolymer diol with a polycarbonate-polar polydimethylsiloxane-polycarbonate structure and a polycarbonate diol, wherein the chain length ratio of the polycarbonate diol to the terpolymer diol is (0.5~1):(2~5), and the mass ratio of the two is (1~2):(8~9).

[0010] The polysiloxane-type polyurethane has a polydisperse molecular weight distribution with a wide molecular weight distribution of 2.5 to 4.0.

[0011] In some embodiments, the hard segment includes diisocyanate, a silicon-containing small molecule diol in the main chain, and a small molecule diamine, wherein the molar ratio of the silicon-containing small molecule diol to the small molecule diamine in the main chain is (5~6):(4~5).

[0012] In feasible embodiments, the diisocyanate includes, but is not limited to, diphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, etc.; the silicon-containing small molecule diols in the main chain include, but are not limited to, 1,3-bis(4-hydroxybutyl)-1,1,3,3-tetramethyldisiloxane; and the small molecule diamines include, but are not limited to, 1,2-ethylenediamine, 1,4-butanediamine, and 1,6-hexanediamine.

[0013] In some embodiments, the soft segments account for 50 wt.% to 55 wt.% of the total mass, and the hard segments account for 45 wt.% to 50 wt.% of the total mass.

[0014] In some embodiments, the polysiloxane-type polyurethane has a wide molecular weight distribution of 2.93 to 3.24.

[0015] In some embodiments, the molecular weight (Mn) of polycarbonate diol is 500-1000.

[0016] In some embodiments, the molecular weight (Mn) of polydimethylsiloxane diol is 500-1000.

[0017] In some embodiments, the molecular weight (Mn) of the polar polydimethylsiloxane diol is 1000-2500.

[0018] In some embodiments, the molecular weight (Mn) of the polycarbonate-polar polydimethylsiloxane-polycarbonate terpolymer diol is 1000-3500.

[0019] In some embodiments, the chain length ratio of the polycarbonate diol to the terpolymer diol is 1:(5~10).

[0020] In some embodiments, the polar polydimethylsiloxane has a unit structure of Formula 1: AA (Formula 1)

[0021] Wherein A is one of the dihydroxy-terminated polysiloxanes such as α,ω-bis(hydroxyethoxypropyl)polydimethylsiloxane and dihydroxypropyl polydimethylsiloxane, and A is connected to A through diphenylmethane diisocyanate (MDI) or hexamethylene diisocyanate (HDI).

[0022] The ternary copolymer diol has a two-unit structure: BAAB (Formula 2)

[0023] B is one of the polycarbonate diols, and the connection between A and A and between A and B is through diphenylmethane diisocyanate (MDI) or hexamethylene diisocyanate (HDI).

[0024] In some embodiments, the chain length ratio of the polycarbonate diol to the terpolymer diol is 1:7 and the mass ratio is 2:8.

[0025] In some embodiments, the solubility parameter of the terpolymer diol is 19.5 MPa^1 / 2, and the solubility parameter of the polycarbonate diol is 20.5 MPa^1 / 2.

[0026] According to another aspect of this application, a method for preparing the above-mentioned polysiloxane-type polyurethane is also provided, comprising:

[0027] Step 1: Prepare a dihydroxyl-terminated (polycarbonate-polar polysiloxane-polycarbonate) terpolymer diol;

[0028] Step 2: The dihydroxyl-terminated (polycarbonate-polar polysiloxane-polycarbonate) terpolymer diol is physically mixed with polyhexamethylene carbonate diol and then vacuum dehydrated to prepare a mixed diol;

[0029] Step 3: React diphenylmethane diisocyanate with the mixed glycol to obtain an isocyanate-terminated prepolymer;

[0030] Step 4: Dilute the prepolymer and add a secondary chain extender to the diluted prepolymer to perform secondary chain extension;

[0031] Step 5: Prepare the main chain extender solution and carry out a chain extension reaction on the prepolymer after secondary chain extension;

[0032] Step 6: Obtain the target polysiloxane-type polyurethane through post-processing.

[0033] According to another aspect of this application, it also includes an apparatus or article of manufacture which is wholly or partially composed of the polysiloxane-type polyurethane described in any of the preceding claims.

[0034] The device or article is a medical device, medical article, implant, or heart valve.

[0035] According to another aspect of this application, there is also a use of a polysiloxane-type polyurethane in the preparation of medical devices, medical articles or implants.

[0036] In another aspect, the present invention provides the use of the above-described polysiloxane-type polyurethane in the preparation of medical devices, medical articles or implants.

[0037] The polysiloxane-type polyurethane of this application, through the synergistic combination of its unique soft segment polarization and long / short chain structural design, wide molecular weight distribution, soft segment molecular weight regulation, introduction of silicon-containing chain extenders, and optimization of the chain extension system, produces a synergistic effect that significantly exceeds the expectations of those skilled in the art. Test data also fully demonstrates that the material provided in this application has achieved groundbreaking progress in biocompatibility, long-term stability, tear resistance, mechanical property balance, and structural controllability, comprehensively surpassing existing conventional systems and comparative materials. It fully meets the stringent requirements of high-performance artificial heart valves for materials that are "tough, strong, stable, and compatible," achieving the goal of simultaneously optimizing multiple core properties. Attached Figure Description

[0038] Figure 1 The molecular formula of a polar polydimethylsiloxane is shown in the embodiments of this application.

[0039] Figure 2 The molecular formula of a ternary polar PDMS copolymer diol is shown in the embodiments of this application.

[0040] Figure 3 This is a comparison diagram showing the degree of microphase separation corresponding to different soft segment components according to an embodiment of this application;

[0041] Figure 4 This is a schematic diagram illustrating the effect of a combination of soft segment components and molecular weight ratios on the tear energy threshold according to an embodiment of this application. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described in further detail below. The described embodiments should not be considered as limitations on the invention. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0043] In the following description, references are made to “some embodiments,” which describe a subset of all possible embodiments. However, it is understood that “some embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.

[0044] Before providing a further detailed description of the embodiments of the present invention, the nouns and terms involved in the embodiments of the present invention will be explained, and the nouns and terms involved in the embodiments of the present invention shall be interpreted as follows.

[0045] The equipment and raw materials used in this application can all be purchased from the market or are commonly used in this field.

[0046] Unless otherwise specified, all contents in this invention are weight percentages, and % contents are weight % contents.

[0047] In this invention, all disclosures of ranges should be considered as disclosures of all sub-ranges and all point values ​​within those ranges. For example, a disclosure of molecular weights of 1000-3000 should be considered as also disclosing ranges such as 1000-1500 and 2000-3000, as well as point values ​​such as 1000, 1500, 2000, and 3000. Similarly, a disclosure of molar ratios of compounds from 1:4 to 4:1 should be considered as disclosing ranges from 1:3 to 2:3.

[0048] The term "polyurethane" includes, at a minimum, both polyurethane and polyurethane urea, unless otherwise stated.

[0049] The term "diisocyanate" refers to a compound that has two isocyanate functional groups per molecule.

[0050] MDI: Diphenylmethane diisocyanate; DMAc: N,N-dimethylacetamide; DCE: Dichloroethane; BDO: 1,4-Butanediol;

[0051] BHTD: 1,3-bis(4-hydroxybutyl)-1,1,3,3-tetramethyldisiloxane; EDA: ethylenediamine; PDMS: polydimethylsiloxane diol; PCDL: polyhexamethylene carbonate diol.

[0052] In this article, "soft segment" refers to a mixed soft segment, specifically a portion composed of polycarbonate and a terpolymer with a polycarbonate-polar polydimethylsiloxane-polycarbonate structure.

[0053] The “hard segment” mentioned in this article refers to the part composed of diisocyanate, silicon-containing small molecule diols in the main chain, and small molecule diamines.

[0054] Polar polydimethylsiloxanes have an AA structure, where A is polydimethylsiloxane diol, the molecular formula of which can be found in [reference needed]. Figure 1 .

[0055] This application constructs a ternary polar PDMS copolymer diol with a (polycarbonate-polar polydimethylsiloxane-polycarbonate) structure based on polar polydimethylsiloxane. The ternary polar PDMS copolymer diol has a BAAB structure. Here, A is a polydimethylsiloxane diol, B is a polycarbonate diol, and A and A or A and B are linked by a (strongly polar molecule) 4,4-diphenylmethane diisocyanate. Its molecular formula is shown below. Figure 2 ,in, Figure 2 R in 1 R 2 Selected from -O-(CH2)2-; R 3 R4 Selected from -(CH2)6-, m is 7-50; n is 3-10.

[0056] Figure 3 A comparison chart of the degree of microphase separation corresponding to different soft segment components is shown. Table 1 shows the solubility parameters of different compounds, where the solubility parameters are used to characterize the polarity of the soft segment in which the compound is located. See also Figure 3 The left figure shows a schematic diagram of the relationship between hard segments and soft segments, where the dashed lines include two hard segments and a soft segment located between the two hard segments. Figure 3 The right figure shows the different structural forms of the two hard segments and the middle soft segment.

[0057] Table 1:

[0058]

[0059] The structure of the hard segment (MDI) + soft segment (PDMS) + hard segment (MDI) is combined with the solubility parameters 15 and 23 of PDMS in Table 1. Due to the large difference in solubility parameters between the two, the microphase separation of the hard and soft segment composition is poor.

[0060] The structure of the strong polar hard segment (MDI) + weak polar soft segment (polar PDMS) + strong polar hard segment (MDI), combined with the solubility parameter of polar PDMS (18.5) and MDI (23) in Table 1, shows that the microphase separation of the soft and hard segment composition is good because the difference between the two solubility parameters is relatively close.

[0061] The structure consists of a strong polar hard segment + a polar PCDL + a weak polar soft segment (polar PDMS) + a polar PCDL + a strong polar hard segment. Referring to Table 1, this combination of hard and soft segments forms a composite structure: MDI-EDA-MDI-BHTD (solubility parameter 23) + PCDL (solubility parameter 20.5) + polar PDMS (solubility parameter 18.5) + PCDL (solubility parameter 20.5) + MDI-EDA-MDI-BHTD (solubility parameter 23). If represented by solubility parameters, this combination forms a structure of 23 + 20.5 + 18.5 + 20.5 + 23, exhibiting a strong-to-second-strong-weak-to-second-strong-strong polarity relationship. This structure allows for a gradual transition from strong polarity (hard segment phase) to second-strong polarity (polycarbonate) and then to weak polarity (polar PDMS), effectively harmonizing the polarity differences between the components. This not only significantly improves the thermodynamic compatibility of the soft and hard segments, but also allows for further control of the microphase separation morphology. The structure described above is achieved by bonding a strongly polar hard segment to a ternary polar PDMS copolymer diol.

[0062] Meanwhile, the inventors of this application discovered that in thermoplastic polyurethane elastomers, the polydispersity of soft segment length directly affects the linking chain structure between hard segment microregions (i.e., physical crosslinking points). Studies have shown that the tear energy threshold is not only positively correlated with the density of physical crosslinking points per unit volume, but also influenced by the length of the linking chains between crosslinking points. The inventors of this application employ linking chains of different lengths in a mixed soft segment system (by setting different chain length ratios in the mixed soft segment system), maintaining a high density of physical crosslinking points while controlling the distribution of linking chain lengths, thereby optimizing the topology of the physical crosslinking network. Simultaneously, in polymers with a wide molecular weight distribution, short chains act as "sacrificial bonds," while long chains act as the supporting backbone. Through interactions with intermolecular hydrogen bonds, both short and long chains can achieve maximized energy dissipation, increasing the material's tear energy threshold and strength. The inventors of this application discovered that selecting a molecular weight distribution in the range of 2.5 to 4, in addition to achieving the above effects, can also reduce the crack propagation rate.

[0063] Combining the two approaches mentioned above can achieve synergistic control of crosslinking point density and linker chain length, which helps to disperse stress, promote molecular chain orientation, and thus effectively improve the tear energy threshold of the material. Figure 4 A schematic diagram illustrating the effect of a combination of soft segment components and molecular weight ratios on the tear energy threshold, as shown in an embodiment of this application, is provided by... Figure 4 It is known that the combination of strong polar hard segment + polar PCDL + weak polar soft segment (polar PDMS) + polar PCDL + strong polar hard segment has an excellent tear energy threshold.

[0064] Based on the above analysis, the inventors provide a method for preparing polysiloxane-type polyurethane, which specifically includes the following steps:

[0065] Step 1: Prepare a dihydroxyl-terminated (polycarbonate-polar polysiloxane-polycarbonate) terpolymer diol.

[0066] In this step, polycarbonate diol (Mn500), polar polydimethylsiloxane diol (Mn2500), and diphenylmethane diisocyanate in a molar ratio of 2:1:2 are reacted in a three-necked flask at 40-80°C for 1-4 hours to obtain a dihydroxyl-terminated (polycarbonate-polar polysiloxane-polycarbonate) terpolymer diol.

[0067] Step 2: Add hexamethylene carbonate diol to the diol of the dihydroxyl-terminated (polycarbonate-polar polysiloxane-polycarbonate) terpolymer to prepare a mixed diol.

[0068] In this step, polyhexamethylene carbonate diol (Mn500) in a mass ratio of 2:8 and a dihydroxyl-terminated (polycarbonate-polysiloxane-polycarbonate) terpolymer are added to a reaction vessel and dehydrated at 100°C to 120°C under vacuum for 1 to 3 hours; after dehydration, a mixed diol is obtained.

[0069] Step 3: React diphenylmethane diisocyanate with the mixed glycol to obtain an isocyanate-terminated prepolymer.

[0070] In this step, a predetermined mass of diphenylmethane diisocyanate (MDI) is weighed and placed in a three-necked flask. The reactor is then preheated in an oil bath at 40–60°C. Subsequently, the mixed diols obtained in step 2 are slowly injected into the reactor using a syringe. After the addition is complete, the reaction continues at 40–80°C for 30–90 minutes to obtain the isocyanate-terminated prepolymer.

[0071] Step 4: Dilute the prepolymer and add a secondary chain extender to the diluted prepolymer for secondary chain extension.

[0072] Add 1,2-dichloroethane (DCE) and N,N-dimethylacetamide (DMAc) to the reaction system of step 3 to dissolve the prepolymer and add the secondary chain extender BHTD; continue to stir the mixture at 40℃~80℃ for 1~3 hours.

[0073] Step 5: Prepare the main chain extender solution and carry out the chain extension reaction on the prepolymer after secondary chain extension.

[0074] The prepolymer obtained in step 4 was diluted with DMAc, and ethylenediamine (EDA) was dissolved in DMAc to prepare a main chain extender solution. Under ice-water bath and stirring conditions, the chain extender solution was added to the reaction system through a syringe pump. After the addition was completed, the reaction was continued in the ice-water bath for 0.5 to 3 hours, and then the reaction mixture was transferred to an oil bath at 40°C to 80°C for 1 to 5 hours to complete the chain extension reaction.

[0075] Step 6: Obtain the target polysiloxane-type polyurethane through post-processing.

[0076] After precipitation, washing, and drying, the reaction solution obtained in step 5 is used to obtain the target polysiloxane-type polyurethane.

[0077] It should be noted that this application selects polyhexamethylene carbonate diol (aliphatic polycarbonate diol) as one of the mixed soft segments, rather than the commonly used aromatic polycarbonate diols containing benzene rings. This is because the purpose of choosing an aliphatic structure is to impart higher flexibility and segment mobility to the molecular chain. Furthermore, the solubility parameters and polarity of the aliphatic structure are designed and matched to be well-suited to the polysiloxane-type polyurethane system designed in this application, which is beneficial for microphase separation and interfacial compatibility between the soft and hard segments, thereby meeting the system's requirements for the overall performance of the soft segments. Existing aromatic polycarbonate diols containing benzene rings do not possess this characteristic.

[0078] The inventors of this application, while designing the structure of the soft segment polarization and long and short chains, the layout of the wide molecular weight distribution, and the control of the soft segment molecular weight, also combined multiple dimensions of technical features such as the ratio of soft and hard segments, the introduction of silicon-containing chain extenders, and the optimization of the chain extension system to produce polysiloxane-type polyurethanes with synergistic effects that significantly exceed the expectations of those skilled in the art.

[0079] III. Examples and Comparative Examples Example 1

[0080] The hard segment content is 45 wt.%, the soft segment ratio (mass ratio) is polycarbonate:polydimethylsiloxane = 75:25, and the chain extender ratio (amount) is BHTD:EDA = 5:5.

[0081] Step 1: Preparation of mixed diols

[0082] Polyhexamethylene carbonate diol (Mn1000) and poly(α,ω-bis(hydroxyethoxypropyl)polydimethylsiloxane) (Mn1000) in a mass ratio of 75:25 were added to a reaction vessel and dehydrated at 105°C under vacuum for 1.5 hours. After dehydration, a mixed diol was obtained.

[0083] Step 2: Preparation of prepolymer

[0084] 6.48 g of diphenylmethane diisocyanate (MDI) was weighed and placed in a tubular reactor, which was preheated in an oil bath at 60°C. Then, 11 g of the mixed glycols obtained in step 1 were slowly injected into the reactor via a syringe at a rate of 0.6 mL / min, with the addition completed in approximately 14.5 minutes (isocyanate index R = 1.02). After the addition was complete, the reaction was continued at 60°C for 35 minutes to obtain the isocyanate-terminated prepolymer.

[0085] Step 3: Dilution of the prepolymer and secondary chain extension

[0086] Add 15 mL of 1,2-dichloroethane (DCE) and 2.5 mL of N,N-dimethylacetamide (DMAc) to the reaction system from step 2 to dissolve the prepolymer, and then add 2.07 g of the secondary chain extender BHTD. Continue stirring the mixture at 60°C for 1.5 hours.

[0087] Step 4: Chain extension reaction

[0088] The reaction solution obtained in step 3 was transferred to a three-necked flask placed in an ice-water bath and diluted with 150 mL of DMAc. Then, 0.45 g of ethylenediamine (EDA) was dissolved in 7.8 mL of DMAc to prepare the main chain extender solution. Under ice-water bath and stirring conditions, this chain extender solution was added to the reaction system at a rate of 0.6 mL / min using a syringe pump. During the addition process, the viscosity of the system increased significantly, but no gelation occurred. After the addition was complete, the reaction was continued in the ice-water bath for 0.5 hours, and then the reaction mixture was transferred to a 60°C oil bath and reacted for 3 hours to complete the chain extension reaction.

[0089] Step 5: Post-processing and product acquisition

[0090] After precipitation, washing, and drying of the reaction solution obtained in step 4, the target polysiloxane-type polyurethane can be obtained. Example 2

[0091] The hard segment content is 45 wt.%, the soft segment ratio (mass ratio) is polycarbonate:polydimethylsiloxane = 50:50, and the chain extender ratio (amount) is BHTD:EDA = 5:5.

[0092] Step 1: Preparation of mixed diols

[0093] Polyhexamethylene carbonate diol (Mn1000) and poly(α,ω-bis(hydroxyethoxypropyl)polydimethylsiloxane) (Mn1000) in a mass ratio of 50:50 were added to a reaction vessel and dehydrated at 105°C under vacuum for 1.5 hours. After dehydration, a mixed diol was obtained.

[0094] Step 2: Preparation of prepolymer

[0095] 6.48 g of diphenylmethane diisocyanate (MDI) was weighed and placed in a tubular reactor, which was preheated in an oil bath at 60°C. Then, 11 g of the mixed glycols obtained in step 1 were slowly injected into the reactor via a syringe at a rate of 0.6 mL / min, with the addition completed in approximately 14.5 minutes (isocyanate index R = 1.02). After the addition was complete, the reaction was continued at 60°C for 35 minutes to obtain the isocyanate-terminated prepolymer.

[0096] Step 3: Dilution of the prepolymer and secondary chain extension

[0097] Add 15 mL of 1,2-dichloroethane (DCE) and 2.5 mL of N,N-dimethylacetamide (DMAc) to the reaction system from step 2 to dissolve the prepolymer, and then add 2.07 g of the secondary chain extender BHTD. Continue stirring the mixture at 60°C for 1.5 hours.

[0098] Step 4: Chain extension reaction

[0099] The reaction solution obtained in step 3 was transferred to a three-necked flask placed in an ice-water bath and diluted with 150 mL of DMAc. Then, 0.45 g of ethylenediamine (EDA) was dissolved in 7.8 mL of DMAc to prepare the main chain extender solution. Under ice-water bath and stirring conditions, this chain extender solution was added to the reaction system at a rate of 0.6 mL / min using a syringe pump. During the addition process, the viscosity of the system increased significantly, but no gelation occurred. After the addition was complete, the reaction was continued in the ice-water bath for 0.5 hours, and then the reaction mixture was transferred to a 60°C oil bath and reacted for 3 hours to complete the chain extension reaction.

[0100] Step 5: Post-processing and product acquisition

[0101] After precipitation, washing, and drying of the reaction solution obtained in step 4, the target polysiloxane-type polyurethane can be obtained. Example 3

[0102] The hard segment content is 45 wt.%, the soft segment ratio (mass ratio) is polycarbonate:polydimethylsiloxane = 20:80, and the chain extender ratio (amount) is BHTD:EDA = 5:5.

[0103] Step 1: Preparation of mixed diols

[0104] Polyhexamethylene carbonate diol (Mn1000) and poly(α,ω-bis(hydroxyethoxypropyl)polydimethylsiloxane) (Mn1000) in a mass ratio of 20:80 were added to a reaction vessel and dehydrated at 105°C under vacuum for 1.5 hours. After dehydration, a mixed diol was obtained.

[0105] Step 2: Preparation of prepolymer

[0106] 6.48 g of diphenylmethane diisocyanate (MDI) was weighed and placed in a tubular reactor, which was preheated in an oil bath at 60°C. Then, 11 g of the mixed glycols obtained in step 1 were slowly injected into the reactor via a syringe at a rate of 0.6 mL / min, with the addition completed in approximately 14.5 minutes (isocyanate index R = 1.02). After the addition was complete, the reaction was continued at 60°C for 35 minutes to obtain the isocyanate-terminated prepolymer.

[0107] Step 3: Dilution of the prepolymer and secondary chain extension

[0108] Add 15 mL of 1,2-dichloroethane (DCE) and 2.5 mL of N,N-dimethylacetamide (DMAc) to the reaction system from step 2 to dissolve the prepolymer, and then add 2.07 g of the secondary chain extender BHTD. Continue stirring the mixture at 60°C for 1.5 hours.

[0109] Step 4: Chain extension reaction

[0110] The reaction solution obtained in step 3 was transferred to a three-necked flask placed in an ice-water bath and diluted with 150 mL of DMAc. Then, 0.45 g of ethylenediamine (EDA) was dissolved in 7.8 mL of DMAc to prepare the main chain extender solution. Under ice-water bath and stirring conditions, this chain extender solution was added to the reaction system at a rate of 0.6 mL / min using a syringe pump. During the addition process, the viscosity of the system increased significantly, but no gelation occurred. After the addition was complete, the reaction was continued in the ice-water bath for 0.5 hours, and then the reaction mixture was transferred to a 60°C oil bath and reacted for 3 hours to complete the chain extension reaction.

[0111] Step 5: Post-processing and product acquisition

[0112] After precipitation, washing, and drying of the reaction solution obtained in step 4, the target polysiloxane-type polyurethane can be obtained. Example 4

[0113] The hard segment content is 35 wt.%, the soft segment ratio (mass ratio) is polycarbonate:polydimethylsiloxane = 20:80, and the chain extender ratio (amount) is BHTD:EDA = 5:5.

[0114] Step 1: Preparation of mixed diols

[0115] Polyhexamethylene carbonate diol (Mn1000) and poly(α,ω-bis(hydroxyethoxypropyl)polydimethylsiloxane) (Mn1000) in a mass ratio of 20:80 were added to a reaction vessel and dehydrated at 105°C under vacuum for 1.5 hours. After dehydration, a mixed diol was obtained.

[0116] Step 2: Preparation of prepolymer

[0117] 5.49 g of diphenylmethane diisocyanate (MDI) was weighed and placed in a tubular reactor, which was preheated in an oil bath at 60°C. Then, 11 g of the mixed glycols obtained in step 1 were slowly injected into the reactor via a syringe at a rate of 0.6 mL / min, with the addition completed in approximately 14.5 minutes (isocyanate index R = 1.02). After the addition was complete, the reaction was continued at 60°C for 35 minutes to obtain the isocyanate-terminated prepolymer.

[0118] Step 3: Dilution of the prepolymer and secondary chain extension

[0119] Add 15 mL of 1,2-dichloroethane (DCE) and 2.5 mL of N,N-dimethylacetamide (DMAc) to the reaction system of step 2 to dissolve the prepolymer, and then add 1.24 g of the secondary chain extender BHTD. Continue stirring the mixture at 60 °C for 1.5 hours.

[0120] Step 4: Chain extension reaction

[0121] The reaction solution obtained in step 3 was transferred to a three-necked flask placed in an ice-water bath and diluted with 150 mL of DMAc. Then, 0.27 g of ethylenediamine (EDA) was dissolved in 7.8 mL of DMAc to prepare the main chain extender solution. Under ice-water bath and stirring conditions, this chain extender solution was added to the reaction system at a rate of 0.6 mL / min using a syringe pump. During the addition process, the viscosity of the system increased significantly, but no gelation occurred. After the addition was complete, the reaction was continued in the ice-water bath for 0.5 hours, and then the reaction mixture was transferred to a 60°C oil bath for 3 hours to complete the chain extension reaction.

[0122] Step 5: Post-processing and product acquisition

[0123] After precipitation, washing, and drying of the reaction solution obtained in step 4, the target polysiloxane-type polyurethane can be obtained. Example 5

[0124] The hard segment content is 40 wt.%, the soft segment ratio (mass ratio) is polycarbonate:polydimethylsiloxane = 20:80, and the chain extender ratio (amount) is BHTD:EDA = 5:5.

[0125] Step 1: Preparation of mixed diols

[0126] Polyhexamethylene carbonate diol (Mn1000) and poly(α,ω-bis(hydroxyethoxypropyl)polydimethylsiloxane) (Mn1000) in a mass ratio of 20:80 were added to a reaction vessel and dehydrated at 105°C under vacuum for 1.5 hours. After dehydration, a mixed diol was obtained.

[0127] Step 2: Preparation of prepolymer

[0128] 5.98 g of diphenylmethane diisocyanate (MDI) was weighed and placed in a tubular reactor, which was preheated in an oil bath at 60°C. Then, 11 g of the mixed glycols obtained in step 1 were slowly injected into the reactor via a syringe at a rate of 0.6 mL / min, with the addition completed in approximately 14.5 minutes (isocyanate index R = 1.02). After the addition was complete, the reaction was continued at 60°C for 35 minutes to obtain the isocyanate-terminated prepolymer.

[0129] Step 3: Dilution of the prepolymer and secondary chain extension

[0130] Add 15 mL of 1,2-dichloroethane (DCE) and 2.5 mL of N,N-dimethylacetamide (DMAc) to the reaction system from step 2 to dissolve the prepolymer, and then add 1.66 g of the secondary chain extender BHTD. Continue stirring the mixture at 60°C for 1.5 hours.

[0131] Step 4: Chain extension reaction

[0132] The reaction solution obtained in step 3 was transferred to a three-necked flask placed in an ice-water bath and diluted with 150 mL of DMAc. Then, 0.36 g of ethylenediamine (EDA) was dissolved in 7.8 mL of DMAc to prepare the main chain extender solution. Under ice-water bath and stirring conditions, this chain extender solution was added to the reaction system at a rate of 0.6 mL / min using a syringe pump. During the addition process, the viscosity of the system increased significantly, but no gelation occurred. After the addition was complete, the reaction was continued in the ice-water bath for 0.5 hours, and then the reaction mixture was transferred to a 60°C oil bath and reacted for 3 hours to complete the chain extension reaction.

[0133] Step 5: Post-processing and product acquisition

[0134] After precipitation, washing, and drying of the reaction solution obtained in step 4, the target polysiloxane-type polyurethane can be obtained. Example 6

[0135] The hard segment content is 50 wt.%, the soft segment ratio (mass ratio) is polycarbonate:polydimethylsiloxane = 20:80, and the chain extender ratio (amount) is BHTD:EDA = 5:5.

[0136] Step 1: Preparation of mixed diols

[0137] Polyhexamethylene carbonate diol (Mn1000) and poly(α,ω-bis(hydroxyethoxypropyl)polydimethylsiloxane) (Mn1000) in a mass ratio of 20:80 were added to a reaction vessel and dehydrated at 105°C under vacuum for 1.5 hours. After dehydration, a mixed diol was obtained.

[0138] Step 2: Preparation of prepolymer

[0139] 6.97 g of diphenylmethane diisocyanate (MDI) was weighed and placed in a tubular reactor, which was preheated in an oil bath at 60°C. Then, 11 g of the mixed diols obtained in step 1 were slowly injected into the reactor via a syringe at a rate of 0.6 mL / min, with the addition completed in approximately 14.5 minutes (isocyanate index R = 1.02). After the addition was complete, the reaction was continued at 60°C for 35 minutes to obtain the isocyanate-terminated prepolymer.

[0140] Step 3: Dilution of the prepolymer and secondary chain extension

[0141] Add 15 mL of 1,2-dichloroethane (DCE) and 2.5 mL of N,N-dimethylacetamide (DMAc) to the reaction system from step 2 to dissolve the prepolymer, and then add 2.49 g of the secondary chain extender BHTD. Continue stirring the mixture at 60°C for 1.5 hours.

[0142] Step 4: Chain extension reaction

[0143] The reaction solution obtained in step 3 was transferred to a three-necked flask placed in an ice-water bath and diluted with 150 mL of DMAc. Then, 0.54 g of ethylenediamine (EDA) was dissolved in 7.8 mL of DMAc to prepare the main chain extender solution. Under ice-water bath and stirring conditions, this chain extender solution was added to the reaction system at a rate of 0.6 mL / min using a syringe pump. During the addition process, the viscosity of the system increased significantly, but no gelation occurred. After the addition was complete, the reaction was continued in the ice-water bath for 0.5 hours, and then the reaction mixture was transferred to a 60°C oil bath and reacted for 3 hours to complete the chain extension reaction.

[0144] Step 5: Post-processing and product acquisition

[0145] After precipitation, washing, and drying of the reaction solution obtained in step 4, the target polysiloxane-type polyurethane can be obtained. Example 7

[0146] The hard segment content is 45 wt.%, the soft segment ratio (mass ratio) is PCDL:PDMS=2:8, and the chain extender ratio (amount of substance) is BHTD:EDA=3:7.

[0147] Step 1: Preparation of mixed diols

[0148] Poly(α,ω-bis(hydroxyethoxypropyl)polydimethylsiloxane) (Mn1000) and polyhexamethylene carbonate diol (Mn1000) in a mass ratio of 4:1 were added to a reaction vessel and dehydrated at 105°C under vacuum for 1.5 hours. After dehydration, a mixed diol was obtained.

[0149] Step 2: Preparation of prepolymer

[0150] 6.91 g of diphenylmethane diisocyanate (MDI) was weighed and placed in a tubular reactor, which was preheated in an oil bath at 60°C. Then, 11 g of the mixed glycols obtained in step 1 were slowly injected into the reactor via a syringe at a rate of 0.6 mL / min, with the addition completed in approximately 14.5 minutes (isocyanate index R = 1.02). After the addition was complete, the reaction was continued at 60°C for 35 minutes to obtain the isocyanate-terminated prepolymer.

[0151] Step 3: Dilution of the prepolymer and secondary chain extension

[0152] Add 15 mL of 1,2-dichloroethane (DCE) and 2.5 mL of N,N-dimethylacetamide (DMAc) to the reaction system from step 2 to dissolve the prepolymer, and then add 1.390 g of the secondary chain extender BHTD. Continue stirring the mixture at 60°C for 1.5 hours.

[0153] Step 4: Chain extension reaction

[0154] The reaction solution obtained in step 3 was transferred to a three-necked flask placed in an ice-water bath and diluted with 150 mL of DMAc. Then, 0.70 g of ethylenediamine (EDA) was dissolved in 7.8 mL of DMAc to prepare the main chain extender solution. Under ice-water bath and stirring conditions, this chain extender solution was added to the reaction system at a rate of 0.6 mL / min using a syringe pump. During the addition process, the viscosity of the system increased significantly, but no gelation occurred. After the addition was complete, the reaction was continued in the ice-water bath for 0.5 hours, and then the reaction mixture was transferred to a 60°C oil bath and reacted for 3 hours to complete the chain extension reaction.

[0155] Step 5: Post-processing and product acquisition

[0156] After precipitation, washing, and drying of the reaction solution obtained in step 4, the target polysiloxane-type polyurethane can be obtained. Example 8

[0157] The hard segment content is 45 wt.%, the soft segment ratio (mass ratio) is PCDL:PDMS=2:8, and the chain extender ratio (amount of substance) is BHTD:EDA=4:6.

[0158] Step 1: Preparation of mixed diols

[0159] Poly(α,ω-bis(hydroxyethoxypropyl)polydimethylsiloxane) (Mn1000) and polyhexamethylene carbonate diol (Mn1000) in a mass ratio of 4:1 were added to a reaction vessel and dehydrated at 105°C under vacuum for 1.5 hours. After dehydration, a mixed diol was obtained.

[0160] Step 2: Preparation of prepolymer

[0161] 6.68 g of diphenylmethane diisocyanate (MDI) was weighed and placed in a tubular reactor, which was preheated in an oil bath at 60°C. Then, 11 g of the mixed diols obtained in step 1 were slowly injected into the reactor via a syringe at a rate of 0.6 mL / min, with the addition completed in approximately 14.5 minutes (isocyanate index R = 1.02). After the addition was complete, the reaction was continued at 60°C for 35 minutes to obtain the isocyanate-terminated prepolymer.

[0162] Step 3: Dilution of the prepolymer and secondary chain extension

[0163] Add 15 mL of 1,2-dichloroethane (DCE) and 2.5 mL of N,N-dimethylacetamide (DMAc) to the reaction system from step 2 to dissolve the prepolymer, and then add 2.64 g of the secondary chain extender BHTD. Continue stirring the mixture at 60°C for 1.5 hours.

[0164] Step 4: Chain extension reaction

[0165] The reaction solution obtained in step 3 was transferred to a three-necked flask placed in an ice-water bath and diluted with 150 mL of DMAc. Then, 0.45 g of ethylenediamine (EDA) was dissolved in 7.8 mL of DMAc to prepare the main chain extender solution. Under ice-water bath and stirring conditions, this chain extender solution was added to the reaction system at a rate of 0.6 mL / min using a syringe pump. During the addition process, the viscosity of the system increased significantly, but no gelation occurred. After the addition was complete, the reaction was continued in the ice-water bath for 0.5 hours, and then the reaction mixture was transferred to a 60°C oil bath and reacted for 3 hours to complete the chain extension reaction.

[0166] Step 5: Post-processing and product acquisition

[0167] After precipitation, washing, and drying of the reaction solution obtained in step 4, the target polysiloxane-type polyurethane can be obtained. Example 9

[0168] The hard segment content is 45 wt.%, the soft segment ratio (mass ratio) is PCDL:PDMS=2:8, and the chain extender ratio (amount of substance) is BHTD:EDA=6:4.

[0169] Step 1: Preparation of mixed diols

[0170] Poly(α,ω-bis(hydroxyethoxypropyl)polydimethylsiloxane) (Mn1000) and polyhexamethylene carbonate diol (Mn1000) in a mass ratio of 4:1 were added to a reaction vessel and dehydrated at 105°C under vacuum for 1.5 hours. After dehydration, a mixed diol was obtained.

[0171] Step 2: Preparation of prepolymer

[0172] 6.29 g of diphenylmethane diisocyanate (MDI) was weighed and placed in a tubular reactor, which was preheated in an oil bath at 60°C. Then, 11 g of the mixed diols obtained in step 1 were slowly injected into the reactor via a syringe at a rate of 0.6 mL / min, with the addition completed in approximately 14.5 minutes (isocyanate index R = 1.02). After the addition was complete, the reaction was continued at 60°C for 35 minutes to obtain the isocyanate-terminated prepolymer.

[0173] Step 3: Dilution of the prepolymer and secondary chain extension

[0174] Add 15 mL of 1,2-dichloroethane (DCE) and 2.5 mL of N,N-dimethylacetamide (DMAc) to the reaction system from step 2 to dissolve the prepolymer, and then add 2.37 g of the secondary chain extender BHTD. Continue stirring the mixture at 60°C for 1.5 hours.

[0175] Step 4: Chain extension reaction

[0176] The reaction solution obtained in step 3 was transferred to a three-necked flask placed in an ice-water bath and diluted with 150 mL of DMAc. Then, 0.34 g of ethylenediamine (EDA) was dissolved in 7.8 mL of DMAc to prepare the main chain extender solution. Under ice-water bath and stirring conditions, this chain extender solution was added to the reaction system at a rate of 0.6 mL / min using a syringe pump. During the addition process, the viscosity of the system increased significantly, but no gelation occurred. After the addition was complete, the reaction was continued in the ice-water bath for 0.5 hours, and then the reaction mixture was transferred to a 60°C oil bath and reacted for 3 hours to complete the chain extension reaction.

[0177] Step 5: Post-processing and product acquisition

[0178] After precipitation, washing, and drying of the reaction solution obtained in step 4, the target polysiloxane-type polyurethane can be obtained. Example 10

[0179] The hard segment content is 45 wt.%, the soft segment ratio (mass ratio) is PCDL:PDMS=2:8, and the chain extender ratio (amount of substance) is BHTD:EDA=7:3.

[0180] Step 1: Preparation of mixed diols

[0181] Poly(α,ω-bis(hydroxyethoxypropyl)polydimethylsiloxane) (Mn1000) and polyhexamethylene carbonate diol (Mn1000) in a mass ratio of 4:1 were added to a reaction vessel and dehydrated at 105°C under vacuum for 1.5 hours. After dehydration, a mixed diol was obtained.

[0182] Step 2: Preparation of prepolymer

[0183] 6.13 g of diphenylmethane diisocyanate (MDI) was weighed and placed in a tubular reactor, which was preheated in an oil bath at 60°C. Then, 11 g of the mixed diols obtained in step 1 were slowly injected into the reactor via a syringe at a rate of 0.6 mL / min, with the addition completed in approximately 14.5 minutes (isocyanate index R = 1.02). After the addition was complete, the reaction was continued at 60°C for 35 minutes to obtain the isocyanate-terminated prepolymer.

[0184] Step 3: Dilution of the prepolymer and secondary chain extension

[0185] Add 15 mL of 1,2-dichloroethane (DCE) and 2.5 mL of N,N-dimethylacetamide (DMAc) to the reaction system of step 2 to dissolve the prepolymer, and then add 2.63 g of the secondary chain extender BHTD. Continue stirring the mixture at 60 °C for 1.5 hours.

[0186] Step 4: Chain extension reaction

[0187] The reaction solution obtained in step 3 was transferred to a three-necked flask placed in an ice-water bath and diluted with 150 mL of DMAc. Then, 0.24 g of ethylenediamine (EDA) was dissolved in 7.8 mL of DMAc to prepare the main chain extender solution. Under ice-water bath and stirring conditions, this chain extender solution was added to the reaction system at a rate of 0.6 mL / min using a syringe pump. During the addition process, the viscosity of the system increased significantly, but no gelation occurred. After the addition was complete, the reaction was continued in the ice-water bath for 0.5 hours, and then the reaction mixture was transferred to a 60°C oil bath and reacted for 3 hours to complete the chain extension reaction.

[0188] Step 5: Post-processing and product acquisition

[0189] After precipitation, washing, and drying of the reaction solution obtained in step 4, the target polysiloxane-type polyurethane can be obtained. Example 11

[0190] The hard segment content is 45 wt.%, the soft segment ratio (mass ratio) is polycarbonate: polar group modified polydimethylsiloxane = 2:8, the soft segment molecular weight ratio is 1:5, and the chain extender ratio (amount) is BHTD:EDA = 6:4.

[0191] Step 1: Preparation of mixed diols

[0192] Polyhexamethylene carbonate diol (Mn500) and polar-modified polydimethylsiloxane (Mn2500) in a mass ratio of 2:8 were added to a reaction vessel and dehydrated at 105°C under vacuum for 1.5 hours. After dehydration, a mixed diol was obtained.

[0193] Step 2: Preparation of prepolymer

[0194] 5.96 g of diphenylmethane diisocyanate (MDI) was weighed and placed in a tubular reactor, which was preheated in an oil bath at 60°C. Then, 11 g of the mixed glycols obtained in step 1 were slowly injected into the reactor via a syringe at a rate of 0.6 mL / min, with the addition completed in approximately 14.5 minutes (isocyanate index R = 1.02). After the addition was complete, the reaction was continued at 60°C for 35 minutes to obtain the isocyanate-terminated prepolymer.

[0195] Step 3: Dilution of the prepolymer and secondary chain extension

[0196] Add 15 mL of 1,2-dichloroethane (DCE) and 2.5 mL of N,N-dimethylacetamide (DMAc) to the reaction system from step 2 to dissolve the prepolymer, and then add 2.66 g of the secondary chain extender BHTD. Continue stirring the mixture at 60°C for 1.5 hours.

[0197] Step 4: Chain extension reaction

[0198] The reaction solution obtained in step 3 was transferred to a three-necked flask placed in an ice-water bath and diluted with 150 mL of DMAc. Then, 0.38 g of ethylenediamine (EDA) was dissolved in 7.8 mL of DMAc to prepare the main chain extender solution. Under ice-water bath and stirring conditions, this chain extender solution was added to the reaction system at a rate of 0.6 mL / min using a syringe pump. During the addition process, the viscosity of the system increased significantly, but no gelation occurred. After the addition was complete, the reaction was continued in the ice-water bath for 0.5 hours, and then the reaction mixture was transferred to a 60°C oil bath and reacted for 3 hours to complete the chain extension reaction.

[0199] Step 5: Post-processing and product acquisition

[0200] After precipitation, washing, and drying of the reaction solution obtained in step 4, the target polysiloxane-type polyurethane can be obtained. Example 12

[0201] The hard segment content is 45 wt.%, the soft segment ratio (mass ratio) is polycarbonate: polar group modified polydimethylsiloxane = 2:8, the soft segment molecular weight ratio is 1:2.5, and the chain extender ratio (molar amount) is BHTD:EDA = 6:4.

[0202] Step 1: Preparation of mixed diols

[0203] Polyhexamethylene carbonate diol (Mn1000) and polydimethylsiloxane (Mn2500) modified with polar groups were added to a reaction vessel at a mass ratio of 2:8 and dehydrated at 105°C under vacuum for 1.5 hours. After dehydration, a mixed diol was obtained.

[0204] Step 2: Preparation of prepolymer

[0205] 5.72 g of diphenylmethane diisocyanate (MDI) was weighed and placed in a tubular reactor, which was preheated in an oil bath at 60°C. Then, 11 g of the mixed diols obtained in step 1 were slowly injected into the reactor via a syringe at a rate of 0.6 mL / min, with the addition completed in approximately 14.5 minutes (isocyanate index R = 1.02). After the addition was complete, the reaction was continued at 60°C for 35 minutes to obtain the isocyanate-terminated prepolymer.

[0206] Step 3: Dilution of the prepolymer and secondary chain extension

[0207] Add 15 mL of 1,2-dichloroethane (DCE) and 2.5 mL of N,N-dimethylacetamide (DMAc) to the reaction system of step 2 to dissolve the prepolymer, and then add 2.87 g of secondary chain extender BHTD. Continue stirring the mixture at 60 °C for 1.5 hours.

[0208] Step 4: Chain extension reaction

[0209] The reaction solution obtained in step 3 was transferred to a three-necked flask placed in an ice-water bath and diluted with 150 mL of DMAc. Then, 0.41 g of ethylenediamine (EDA) was dissolved in 7.8 mL of DMAc to prepare the main chain extender solution. Under ice-water bath and stirring conditions, this chain extender solution was added to the reaction system at a rate of 0.6 mL / min using a syringe pump. During the addition process, the viscosity of the system increased significantly, but no gelation occurred. After the addition was complete, the reaction was continued in the ice-water bath for 0.5 hours, and then the reaction mixture was transferred to a 60°C oil bath and reacted for 3 hours to complete the chain extension reaction.

[0210] Step 5: Post-processing and product acquisition

[0211] After precipitation, washing, and drying of the reaction solution obtained in step 4, the target polysiloxane-type polyurethane can be obtained. Example 13

[0212] The hard segment content is 45 wt.%, the soft segment ratio (mass ratio) is polycarbonate: polar group modified polydimethylsiloxane = 2:8, the soft segment molecular weight ratio is 1:1, and the chain extender ratio (amount of substance) is BHTD:EDA = 6:4.

[0213] Step 1: Preparation of mixed diols

[0214] Polyhexamethylene carbonate diol (Mn1000) in a mass ratio of 2:8 and polydimethylsiloxane (Mn1000) modified with polar groups were added to a reaction vessel and dehydrated at 105°C under vacuum for 1.5 hours. After dehydration, a mixed diol was obtained.

[0215] Step 2: Preparation of prepolymer

[0216] 6.29 g of diphenylmethane diisocyanate (MDI) was weighed and placed in a tubular reactor, which was preheated in an oil bath at 60°C. Then, 11 g of the mixed diols obtained in step 1 were slowly injected into the reactor via a syringe at a rate of 0.6 mL / min, with the addition completed in approximately 14.5 minutes (isocyanate index R = 1.02). After the addition was complete, the reaction was continued at 60°C for 35 minutes to obtain the isocyanate-terminated prepolymer.

[0217] Step 3: Dilution of the prepolymer and secondary chain extension

[0218] Add 15 mL of 1,2-dichloroethane (DCE) and 2.5 mL of N,N-dimethylacetamide (DMAc) to the reaction system from step 2 to dissolve the prepolymer, and then add 2.37 g of the secondary chain extender BHTD. Continue stirring the mixture at 60°C for 1.5 hours.

[0219] Step 4: Chain extension reaction

[0220] The reaction solution obtained in step 3 was transferred to a three-necked flask placed in an ice-water bath and diluted with 150 mL of DMAc. Then, 0.34 g of ethylenediamine (EDA) was dissolved in 7.8 mL of DMAc to prepare the main chain extender solution. Under ice-water bath and stirring conditions, this chain extender solution was added to the reaction system at a rate of 0.6 mL / min using a syringe pump. During the addition process, the viscosity of the system increased significantly, but no gelation occurred. After the addition was complete, the reaction was continued in the ice-water bath for 0.5 hours, and then the reaction mixture was transferred to a 60°C oil bath and reacted for 3 hours to complete the chain extension reaction.

[0221] Step 5: Post-processing and product acquisition

[0222] After precipitation, washing, and drying of the reaction solution obtained in step 4, the target polysiloxane-type polyurethane can be obtained. Example 14

[0223] The hard segment content is 45 wt.%, the soft segment ratio (mass ratio) is polycarbonate:polydimethylsiloxane with polar groups = 2:8, the soft segment molecular weight ratio = 1:10, and the chain extender ratio (amount of substance) is BHTD:EDA = 6:4.

[0224] Step 1: Prepare a dihydroxyl-terminated (polycarbonate-polar polysiloxane-polycarbonate) terpolymer.

[0225] Polyhexamethylene carbonate diol (Mn500), polydimethylsiloxane (Mn2500) with polar groups, and diphenylmethane diisocyanate in a molar ratio of 2:1:2 were reacted in a three-necked flask at 80°C for 3 hours to obtain a dihydroxyl-terminated (polycarbonate-polar polysiloxane-polycarbonate) terpolymer.

[0226] Step 2: Prepare mixed diols.

[0227] Polyhexamethylene carbonate diol (Mn500) in a mass ratio of 2:8 and a dihydroxyl-terminated (polycarbonate-polar polysiloxane-polycarbonate) terpolymer (Mn5000) were added to a reaction vessel and dehydrated at 105°C under vacuum for 1.5 hours. After dehydration, a mixed diol was obtained.

[0228] Step 3: Preparation of prepolymer

[0229] 6.15 g of diphenylmethane diisocyanate (MDI) was weighed and placed in a tubular reactor, which was then preheated in an oil bath at 80°C. Subsequently, 11 g of the mixed diols obtained in step 2 were slowly injected into the tubular reactor via a syringe at a rate of 0.6 mL / min, with the addition completed in approximately 14.5 minutes (isocyanate index R = 1.02). After the addition was complete, the reaction was continued at 80°C for 60 minutes to obtain the isocyanate-terminated prepolymer.

[0230] Step 4: Dilution of the prepolymer and secondary chain extension

[0231] Add 15 mL of 1,2-dichloroethane (DCE) and 2.5 mL of N,N-dimethylacetamide (DMAc) to the reaction system from step 3 to dissolve the prepolymer, and then add 2.49 g of the secondary chain extender BHTD. Continue stirring the mixture at 80°C for 1.5 hours.

[0232] Step 5: Chain extension reaction

[0233] The reaction solution obtained in step 4 was transferred to a three-necked flask placed in an ice-water bath and diluted with 150 mL of DMAc. Then, 0.37 g of ethylenediamine (EDA) was dissolved in 7.8 mL of DMAc to prepare the main chain extender solution. Under ice-water bath and stirring conditions, this chain extender solution was added to the reaction system at a rate of 0.6 mL / min using a syringe pump. During the addition process, the viscosity of the system increased significantly, but no gelation occurred. After the addition was complete, the reaction was continued in the ice-water bath for 0.5 hours, and then the reaction mixture was transferred to an 80°C oil bath and reacted for 3 hours to complete the chain extension reaction.

[0234] Step 6: Post-processing and product acquisition

[0235] After precipitation, washing, and drying of the reaction solution obtained in step 5, the target polysiloxane-type polyurethane can be obtained. Example 15

[0236] The hard segment content is 45 wt.%, the soft segment ratio (mass ratio) is polycarbonate:polydimethylsiloxane with polar groups = 2:8, the soft segment molecular weight ratio = 1:10, and the chain extender ratio (amount of substance) is BHTD:EDA = 6:4.

[0237] Step 1: Prepare a dihydroxyl-terminated (polycarbonate-polar polysiloxane-polycarbonate) terpolymer.

[0238] Polyhexamethylene carbonate diol (Mn500), polydimethylsiloxane (Mn2500) with polar groups, and diphenylmethane diisocyanate in a molar ratio of 2:1:2 were reacted in a three-necked flask at 80°C for 3 hours to obtain a dihydroxyl-terminated (polycarbonate-polar polysiloxane-polycarbonate) terpolymer.

[0239] Step 2: Prepare mixed diols.

[0240] Polyhexamethylene carbonate diol (Mn500) in a mass ratio of 2:8 and a dihydroxyl-terminated (polycarbonate-polar polysiloxane-polycarbonate) terpolymer (Mn5000) were added to a reaction vessel and dehydrated at 105°C under vacuum for 1.5 hours. After dehydration, a mixed diol was obtained.

[0241] Step 3: Preparation of prepolymer

[0242] 6.15 g of diphenylmethane diisocyanate (MDI) was weighed and placed in a tubular reactor, which was then preheated in an oil bath at 50°C. Subsequently, 11 g of the mixed diols obtained in step 2 were slowly injected into the tubular reactor via a syringe at a rate of 0.6 mL / min, with the addition completed in approximately 14.5 minutes (isocyanate index R = 1.02). After the addition was complete, the reaction was continued at 50°C for 60 minutes to obtain the isocyanate-terminated prepolymer.

[0243] Step 4: Dilution of the prepolymer and secondary chain extension

[0244] Add 15 mL of 1,2-dichloroethane (DCE) and 2.5 mL of N,N-dimethylacetamide (DMAc) to the reaction system from step 3 to dissolve the prepolymer, and then add 2.49 g of the secondary chain extender BHTD. Continue stirring the mixture at 50°C for 1.5 hours.

[0245] Step 5: Chain extension reaction

[0246] The reaction solution obtained in step 4 was transferred to a three-necked flask placed in an ice-water bath and diluted with 150 mL of DMAc. Then, 0.37 g of ethylenediamine (EDA) was dissolved in 7.8 mL of DMAc to prepare the main chain extender solution. Under ice-water bath and stirring conditions, this chain extender solution was added to the reaction system at a rate of 0.6 mL / min using a syringe pump. During the addition process, the viscosity of the system increased significantly, but no gelation occurred. After the addition was complete, the reaction was continued in the ice-water bath for 0.5 hours, and then the reaction mixture was transferred to a 50°C oil bath and reacted for 3 hours to complete the chain extension reaction.

[0247] Step 6: Post-processing and product acquisition

[0248] After precipitation, washing, and drying of the reaction solution obtained in step 5, the target polysiloxane-type polyurethane can be obtained.

[0249] Compare with Example 1

[0250] The hard segment content is 45 wt.%, the soft segment ratio (mass ratio) is polycarbonate:polydimethylsiloxane = 2:8, the soft segment molecular weight ratio is 1:1, and the chain extender is a single chain extender 1,4-butanediol.

[0251] Step 1: Preparation of mixed diols

[0252] Polyhexamethylene carbonate diol (Mn1000) in a mass ratio of 2:8 and polydimethylsiloxane (Mn1000) modified with polar groups were added to a reaction vessel and dehydrated at 105°C under vacuum for 1.5 hours. After dehydration, a mixed diol was obtained.

[0253] Step 2: Preparation of prepolymer

[0254] 8.02 g of diphenylmethane diisocyanate (MDI) was weighed and placed in a tubular reactor, which was preheated in an oil bath at 60°C. Then, 11 g of the mixed diols obtained in step 1 were slowly injected into the reactor via a syringe at a rate of 0.6 mL / min, with the addition completed in approximately 14.5 minutes (isocyanate index R = 1.02). After the addition was complete, the reaction was continued at 60°C for 35 minutes to obtain the isocyanate-terminated prepolymer.

[0255] Step 3: Dilution of the prepolymer and secondary chain extension

[0256] Add 200 mL of N,N-dimethylacetamide (DMAc) to the reaction system from step 2 to dissolve the prepolymer, and then add 1.99 g of chain extender BDO. Continue stirring the mixture at 60°C for 3 hours to complete the chain extension reaction.

[0257] Step 4: Post-processing and product acquisition

[0258] After precipitation, washing, and drying of the reaction solution obtained in step 4, the target polysiloxane-type polyurethane can be obtained.

[0259] Compare with Example 2

[0260] The hard segment content is 45 wt.%, the soft segment ratio (mass ratio) is polycarbonate:polydimethylsiloxane = 2:8, the soft segment molecular weight ratio is 1:1, and the chain extender ratio (amount of substance) is BDO:EDA = 6:4.

[0261] Step 1: Preparation of mixed diols

[0262] Polyhexamethylene carbonate diol (Mn1000) in a mass ratio of 2:8 and polydimethylsiloxane (Mn1000) modified with polar groups were added to a reaction vessel and dehydrated at 105°C under vacuum for 1.5 hours. After dehydration, a mixed diol was obtained.

[0263] Step 2: Preparation of prepolymer

[0264] 8.26 g of diphenylmethane diisocyanate (MDI) was weighed and placed in a tubular reactor, which was preheated in an oil bath at 60°C. Then, 11 g of the mixed diols obtained in step 1 were slowly injected into the reactor via a syringe at a rate of 0.6 mL / min, with the addition completed in approximately 14.5 minutes (isocyanate index R = 1.02). After the addition was complete, the reaction was continued at 60°C for 35 minutes to obtain the isocyanate-terminated prepolymer.

[0265] Step 3: Dilution of the prepolymer and secondary chain extension

[0266] Add 15 mL of 1,2-dichloroethane (DCE) and 2.5 mL of N,N-dimethylacetamide (DMAc) to the reaction system from step 2 to dissolve the prepolymer, and then add 1.26 g of the secondary chain extender BHTD. Continue stirring the mixture at 60°C for 1.5 hours.

[0267] Step 4: Chain extension reaction

[0268] The reaction solution obtained in step 3 was transferred to a three-necked flask placed in an ice-water bath and diluted with 150 mL of DMAc. Then, 0.69 g of ethylenediamine (EDA) was dissolved in 7.8 mL of DMAc to prepare the main chain extender solution. Under ice-water bath and stirring conditions, this chain extender solution was added to the reaction system at a rate of 0.6 mL / min using a syringe pump. During the addition process, the viscosity of the system increased significantly, but no gelation occurred. After the addition was complete, the reaction was continued in the ice-water bath for 0.5 hours, and then the reaction mixture was transferred to a 60°C oil bath and reacted for 3 hours to complete the chain extension reaction.

[0269] Step 4: Post-processing and product acquisition

[0270] After precipitation, washing, and drying of the reaction solution obtained in step 4, the target polysiloxane-type polyurethane can be obtained.

[0271] To verify the comprehensive performance advantages and technological innovation of the polysiloxane-type polyurethane provided in this application in valve materials, the inventors of this application designed and prepared the above-mentioned 15 sets of examples (Examples 1–15) and 2 sets of control examples (Control Examples 1–2), and conducted systematic performance tests on them, including key indicators such as cytotoxicity, hemolysis, antithrombotic adhesion, antioxidant and hydrolytic degradation ability, anti-calcium ion deposition ability, tear energy threshold, tensile mechanical properties, creep and permanent deformation, molecular weight and its distribution. All the above test methods were conducted in accordance with the latest relevant standards.

[0272] In Examples 1–10, common polydimethylsiloxane (PDMS) was used as the soft segment component, and parameters such as the soft segment ratio, hard segment content, and chain extender ratio were adjusted as a performance comparison baseline.

[0273] In Examples 11–15, the molecular weight ratio of the soft segments was optimized, and the polarity of polydimethylsiloxane was improved by pre-copolymerization or bridging polar molecules, and this was used as part of the soft segment component, reflecting the core innovative structure of the present invention. In Example 14, polycarbonate-polar polydimethylsiloxane-polycarbonate terpolymer diol and polycarbonate diol were used as mixed soft segments, and the molecular weight ratio of the soft segments was 1:7, which yielded the best results in all aspects.

[0274] Comparative Example 1: A single chain extender, BDO, was used instead of the silicon-containing chain extender, BHTD.

[0275] Comparative Example 2: BDO and EDA were mixed for chain extension, but BHTD, a silicon-containing chain extender, was not used.

[0276] The comprehensive performance of the polysiloxane-type polyurethane provided in this application in valve materials is shown in Tables 2 and 3.

[0277] Table 2:

[0278]

[0279] Table 3:

[0280]

[0281] The performance and advantages of polysiloxane-type polyurethanes in Table 2-3 are analyzed and explained in detail below.

[0282] (a) Optimization and balance of mechanical properties:

[0283] From the mechanical data in Table 1, we can see that:

[0284] While Comparative Examples 1-2 exhibited high tensile strength (>57 MPa) and modulus (>117 MPa), their elongation at break was low (<261%), indicating a brittle and hard material with poor mechanical behavior matching that of natural vascular tissue. Examples 11-15, while maintaining excellent tensile strength (36.57–42.09 MPa), achieved extremely high elongation at break (528%–607%), and their tensile modulus (18.37–22.17 MPa) was closer to that of biological soft tissue. This embodies an ideal mechanical balance of high strength, high elongation, and suitable modulus. When applied to bioprosthetic valves, this material helps the valves achieve more biomimetic opening and closing movements in vivo and reduces stress damage to surrounding tissues. Furthermore, the creep growth rate and permanent deformation rate of Examples 11-15 were also at extremely low levels (<4.04% and <1.87%, respectively), indicating that the material has excellent dimensional stability and resistance to plastic deformation under long-term stress. If applied to the fabrication of biological valves, this is the basis for ensuring the long-term geometric shape and functional integrity of the valve.

[0285] (ii) Molecular weight distribution and structure-property relationship

[0286] Table 2 also shows that the molecular weight distribution (PDI) of Examples 11-15 was selected from 2.93 to 3.24 within the range of 2.5 to 4.0. The molecular weight distribution design in this application is partly derived from process optimization, but the majority comes from the molecular design of different soft segment molecular weights. As shown in Table 1, the molecular weights of polar PDMS and (polycarbonate-polar PDMS-polycarbonate) terpolymer diol are 2500 and 3500, respectively, which, together with PDCL (Mn500), form part of the soft segment. By selecting soft segments with different molecular weights, a specific molecular weight distribution was achieved. A moderately wide distribution is beneficial to the synergistic effect of molecular chains of different lengths, ensuring mechanical properties while contributing excellent toughness and tear resistance. In contrast, Control Example 1 (1.47), with an excessively narrow PDI, although having a uniform molecular weight, had the lowest tear energy and elongation at break; while the material of this invention with a PDI within the preferred range achieved comprehensive performance optimization. This confirms that using a wide molecular weight distribution as a key control parameter in this application has an unexpectedly important role in achieving the superior overall performance of the final product.

[0287] (III) Significant improvement in biocompatibility and long-term stability

[0288] As shown in Table 2, all samples obtained in the examples passed the cytotoxicity and hemolysis tests, indicating that the materials have good basic biocompatibility. However, in the more stringent key indicators for evaluating long-term implantation stability, such as antithrombotic adhesion, anti-oxidative / hydrolytic degradation, and anti-calcification, Examples 11-15 all showed an "excellent" rating, significantly better than Examples 1-10 and the control, which showed a "good" rating. This is because using polar polydimethylsiloxane as part of the soft segment improves the thermodynamic compatibility between polydimethylsiloxane and urethane. As shown in Table 1, the solubility parameters of polar PDMS and (polycarbonate-polar PDMS-polycarbonate) terpolymer diol increase, reducing the gap with the hard segment raw materials, thereby improving the degree of microphase separation, making the connections between components tighter, and reducing the attack of reactive oxygen species and water molecules on the molecular chains. At the same time, the appropriate degree of microphase separation reduces platelet adhesion and non-specific protein adsorption, thereby reducing the possibility of thrombus viscosity and calcification deposition. This result directly confirms that the synergistic effect of copolymerizing or bridging polar polydimethylsiloxane with polycarbonate significantly enhances the compatibility of the material with the biological environment and inhibits performance degradation caused by oxidation, hydrolysis and calcium ion deposition, which is crucial for artificial heart valve materials that require a service life of decades.

[0289] (iv) Breakthrough improvement in tearing energy threshold

[0290] The tear energy threshold is a key indicator for measuring a material's resistance to crack propagation. When applied to the fabrication of biological valves, it directly relates to the valve's fatigue and damage resistance under long-term dynamic loads. As shown in Table 2:

[0291] The tear energy thresholds of Examples 1-10 (conventional PDMS systems) range from 67.15 to 80.97 J / m².

[0292] The control example 1 (single BDO extended chain) had the lowest tear energy, at only 52.19 J / m².

[0293] The tear energy thresholds of Examples 11-15 were significantly improved to 117.29~154.57 J / m². Among them, Example 14 (introducing a ternary copolymer soft segment structure) had a tear energy as high as 154.57 J / m², which is about three times that of Control Example 1 and about 91% higher than the optimal conventional PDMS system example (10, 80.97 J / m²). At the same time, the strategy of combining the optimized molecular weight ratio (1:7) with the synergistic effect of silicon-containing chain extenders greatly enhanced the intrinsic toughness of the material while maintaining its elasticity, effectively solving the bottleneck problem of traditional materials being "strong but not tough" or "tough but not strong".

[0294] In summary, the polysiloxane-type polyurethane of this application, through the synergistic combination of its unique soft segment polarization and long / short chain structural design, wide molecular weight distribution, soft / hard segment ratio, soft segment molecular weight control, introduction of silicon-containing chain extenders, and optimization of the chain extension system, produces a synergistic effect that significantly exceeds the expectations of those skilled in the art. Test data fully demonstrate that this material has achieved groundbreaking progress in biocompatibility and long-term stability, tear resistance, mechanical property balance, and structural controllability, comprehensively surpassing existing conventional systems and comparative materials. It fully meets the stringent requirements of high-performance artificial heart valves for materials that are "tough, strong, stable, and compatible," achieving the goal of simultaneously optimizing multiple core properties.

[0295] The above description is merely an embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A polysiloxane-type polyurethane, composed of soft segments and hard segments, characterized in that: The soft segment is a hybrid soft segment, comprising a terpolymer diol with a polycarbonate-polar polydimethylsiloxane-polycarbonate structure and a polycarbonate diol; The polar polydimethylsiloxane has a unit structure of Formula 1: AA (Formula 1) Wherein A is selected from α,ω-bis(hydroxyethoxypropyl)polydimethylsiloxane or bishydroxypropylpolydimethylsiloxane in dihydroxy-terminated polysiloxanes, and A is connected to A by diphenylmethane diisocyanate (MDI) or hexamethylene diisocyanate (HDI). The terpolymer diol has a unit structure of Formula 2: BAAB (Formula 2) B is one of the polycarbonate diols, and the connection between A and A and between A and B is through diphenylmethane diisocyanate (MDI) or hexamethylene diisocyanate (HDI). The chain length ratio of the polycarbonate diol to the terpolymer diol is (0.5~1):(2~5); The mass ratio of the polycarbonate diol to the terpolymer diol is (1~2):(8~9). The polysiloxane-type polyurethane has a polydisperse molecular weight distribution with a wide molecular weight distribution of 2.5 to 4.

0. The soft segments account for 50 wt.% to 55 wt.% of the total mass, and the hard segments account for 45 wt.% to 50 wt.% of the total mass.

2. The polysiloxane-type polyurethane according to claim 1, characterized in that, The hard segment includes diisocyanate, a silicon-containing small molecule diol in the main chain, and a small molecule diamine, wherein the molar ratio of the silicon-containing small molecule diol to the small molecule diamine in the main chain is (5~6):(4~5).

3. The polysiloxane-type polyurethane according to claim 1, characterized in that, The polysiloxane-type polyurethane has a wide molecular weight distribution of 2.93~3.

24.

4. The polysiloxane-type polyurethane according to any one of claims 1 to 3, characterized in that, The molecular weight ratio of the polycarbonate diol to the terpolymer diol is 1:(5~10).

5. The polysiloxane-type polyurethane according to claim 1, characterized in that, The solubility parameter of the terpolymer diol is 19.5 MPa^1 / 2, and the solubility parameter of the polycarbonate diol is 20.5 MPa^1 / 2.

6. The method for preparing polysiloxane-type polyurethane according to any one of claims 1-5, characterized in that, include: Step 1: Prepare a dihydroxyl-terminated (polycarbonate-polar polysiloxane-polycarbonate) terpolymer diol; Step 2: The dihydroxyl-terminated (polycarbonate-polar polysiloxane-polycarbonate) terpolymer diol is physically mixed with polyhexamethylene carbonate diol and then vacuum dehydrated to prepare a mixed diol; Step 3: React diphenylmethane diisocyanate with the mixed glycol to obtain an isocyanate-terminated prepolymer; Step 4: Dilute the prepolymer and add the secondary chain extender 1,3-bis(4-hydroxybutyl)-1,1,3,3-tetramethyldisiloxane to the diluted prepolymer for secondary chain extension. Step 5: Dissolve ethylenediamine (EDA) in DMAc to prepare a main chain extender solution, and perform a chain extension reaction on the prepolymer after secondary chain extension; Step 6: Obtain the target polysiloxane-type polyurethane through post-processing.

7. An article characterized in that, The article is composed entirely or partially of the polysiloxane-type polyurethane as described in any one of claims 1-5; The product is a medical product or a graft.

8. An apparatus, characterized in that, The device is composed entirely or partially of the polysiloxane-type polyurethane as described in any one of claims 1-5; The device is a medical device.

9. Use of the polysiloxane-type polyurethane according to any one of claims 1-5 in the preparation of medical devices, medical articles or implants.

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