Hydrogen bond-mediated high-strength composite polyurethane elastomers and methods for making the same
By introducing aromatic small molecules into polyurethane elastomers to form hydrogen bond-mediated composite materials, the problem of insufficient mechanical properties of traditional polyurethane materials is solved, achieving a balance between high strength and recyclability, making it suitable for high-performance equipment and structural components.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- BEIJING INST OF TECH
- Filing Date
- 2026-03-25
- Publication Date
- 2026-05-29
AI Technical Summary
Traditional polyurethane materials suffer from insufficient mechanical properties in high-performance applications. In particular, the mechanical properties of thermoplastic polyurethane cannot meet the requirements of high-strength structural components and wear-resistant materials. At the same time, it is difficult to balance the recyclability of linear structures with the high strength of cross-linked networks.
By introducing aromatic small molecules as hydrogen bond mediating units into polyurethane elastomers and regulating their mass fraction ratio with polyurethane substrates, dynamic hydrogen bond density and physical cross-linking are formed, thereby improving the mechanical properties of the material without sacrificing recyclability.
The prepared hydrogen bond-mediated composite polyurethane elastomer significantly improves tensile strength and recyclability without the use of crosslinking agents, making it suitable for equipment and structural components with high strength and durability requirements.
Smart Images
Figure CN122103872A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a hydrogen bond-mediated high-strength composite polyurethane elastomer and its preparation method, belonging to the field of polyurethane materials technology. Background Technology
[0002] Polyurethane (PU), as a high-performance polymer material, is widely used in automotive, construction, and electronic medical fields due to its tunable hardness and versatility. However, traditional polyurethane, especially thermoplastic polyurethane (TPU), has significant mechanical property defects, which severely restricts its application in high-performance scenarios. Taking the automotive industry as an example, although polyurethane is used to manufacture non-load-bearing components such as seats and dashboards, in structural components requiring high strength, the insufficient mechanical properties of TPU make it difficult to replace metals or thermosetting polyurethanes. Similarly, in the fields of sporting goods and industrial wear-resistant materials, the tensile strength, impact resistance, and fatigue resistance of TPU often fail to meet the requirements for long-term use.
[0003] The limitations of these mechanical properties are closely related to their molecular structure. While thermosetting polyurethanes possess high strength due to their three-dimensional cross-linked network, they sacrifice recyclability; and while the linear molecular structure of TPU facilitates recycling, it leads to a significant reduction in its mechanical strength and heat resistance.
[0004] The current research bottleneck is that if mechanical properties are improved by increasing crosslinking density, recyclability will be sacrificed; if a linear structure is maintained to ensure recyclability, it is difficult to achieve a breakthrough in mechanical properties. Summary of the Invention
[0005] In view of this, the purpose of the present invention is to provide a hydrogen bond-mediated high-strength composite polyurethane elastomer and its preparation method.
[0006] To achieve the above objectives, the technical solution of the present invention is as follows.
[0007] A method for preparing a hydrogen bond-mediated high-strength composite polyurethane elastomer, comprising the following steps:
[0008] (1) Under a protective gas atmosphere (such as nitrogen, argon, etc.), polyether polyol and 4,4'-diphenylmethane diisocyanate (MDI) are mixed and reacted at 60~90℃ for 1~6h to obtain a prepolymer. A chemical foaming agent is added to the prepolymer and reacted at 60~80℃ for 3~24h to obtain foamed polyurethane. (2) Dissolve expanded polyurethane in an organic solvent and heat at 30~80℃ for 12~24h to obtain a viscous liquid product. Dry the product to obtain a polyurethane elastomer substrate. (3) Dissolve the polyurethane elastomer substrate and the aromatic small molecule compound in an organic solvent, then pour them into a mold and dry them to obtain a hydrogen bond-mediated high-strength composite polyurethane elastomer. The total mass of polyurethane elastomer substrate and aromatic small molecule compound is 100%, the mass fraction of polyurethane elastomer substrate is 80%~99%, and the mass fraction of aromatic small molecule compound is 1%~20%.
[0009] Preferably, in step (1), the polyether polyol is PTMG1000 and / or PTMG2000.
[0010] Preferably, the chemical foaming agent is water.
[0011] Preferably, in step (1), the total mass of polyether polyol, MDI and chemical foaming agent is 100%, the mass fraction of polyether polyol is 65.9%~79.4%, the mass fraction of MDI is 19.9%~32.9%, and the mass fraction of chemical foaming agent is 0.7%~1.2%.
[0012] Preferably, in step (2), the organic solvent is one or more of N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, and tetrahydrofuran.
[0013] Preferably, in step (3), the aromatic small molecule compound is dibenzoylhydrazine and / or diphenylaminourea.
[0014] Preferably, in step (3), the total mass of the polyurethane elastomer substrate and the aromatic small molecule compound is 100%, the mass fraction of the polyurethane elastomer substrate is 85%~95%, and the mass fraction of the aromatic small molecule compound is 5%~15%.
[0015] Preferably, in step (3), the organic solvent is one or more of N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, and tetrahydrofuran.
[0016] Preferably, in step (3), the drying temperature is 50~100℃.
[0017] A hydrogen bond-mediated high-strength composite polyurethane elastomer was prepared by the above method.
[0018] Beneficial effects This invention introduces aromatic small molecules as hydrogen bond mediating units into a polyurethane elastomer substrate and further controls the mass fraction ratio of the polyurethane elastomer substrate to the aromatic small molecules. Without using crosslinking agents or forming irreversible chemical crosslinks, it significantly improves the dynamic hydrogen bond density and physical crosslinking effect within the system, fundamentally overcoming the technical bottleneck of traditional polyurethane's "high strength but non-recyclable, insufficient recyclable strength." The prepared hydrogen bond-mediated composite polyurethane elastomer possesses both excellent mechanical strength and good recyclability, with a tensile strength reaching up to 64 MPa. It can be widely used in advanced equipment, structural components, and high-performance wear-resistant materials with high requirements for strength, durability, and green recycling. Attached Figure Description
[0019] Figure 1 The tensile strength curves of the composite polyurethane elastomers obtained in Examples 1-4 of this invention are shown.
[0020] Figure 2 The tensile strength curves of the composite polyurethane elastomers obtained in Examples 3 and 5 of this invention are shown. Detailed Implementation
[0021] The present invention will be further described in detail below with reference to specific embodiments.
[0022] Example 1 This embodiment provides a hydrogen bond-mediated high-strength composite polyurethane elastomer and its preparation method, specifically including the following steps: Step 1: PTMG1000 and MDI are mixed and heated at 60°C for 1 hour under an argon atmosphere. Deionized water is then added to obtain the prepolymer. The total mass of the prepolymer is 100%, with PTMG1000, MDI, and deionized water comprising 65.9%, 32.9%, and 1.2% of the total mass, respectively.
[0023] Step 2: Heat the above prepolymer at 60°C for 3 hours to obtain foamed polyurethane.
[0024] Step 3: Dissolve the polyurethane foam in N,N-dimethylacetamide, and then heat at 30°C for 12 h to obtain a viscous liquid product.
[0025] Step four: Dry the obtained viscous product to obtain a polyurethane elastomer substrate.
[0026] Step 5: Dissolve the polyurethane elastomer substrate and diphenylaminourea in N,N-dimethylformamide. Specifically, the mass fractions of the polyurethane elastomer substrate and diphenylaminourea are 99% and 1%, respectively.
[0027] Step six: Place the dissolved solution in a mold and dry it to obtain a composite polyurethane elastomer film at a drying temperature of 50°C.
[0028] The tensile strength curve of the composite polyurethane elastomer is as follows: Figure 1 As shown.
[0029] Example 2 This embodiment provides a hydrogen bond-mediated high-strength composite polyurethane elastomer and its preparation method, specifically including the following steps: Step 1: PTMG1000 and MDI are mixed and heated at 90°C for 6 hours under an argon atmosphere. Deionized water is then added to obtain the prepolymer. The total mass of the prepolymer is 100%, with PTMG1000, MDI, and deionized water comprising 65.9%, 32.9%, and 1.2% of the total mass, respectively.
[0030] Step 2: The prepolymer is heated at 80°C for 24 hours to obtain foamed polyurethane.
[0031] Step 3: Dissolve the polyurethane foam in N,N-dimethylacetamide and then heat at 80°C for 24 h to obtain a viscous liquid product.
[0032] Step four: Dry the obtained viscous product to obtain a polyurethane elastomer substrate.
[0033] Step 5: Dissolve the polyurethane elastomer substrate and diphenylaminourea in N,N-dimethylacetamide. Specifically, the mass fractions of the polyurethane elastomer substrate and diphenylaminourea are 90% and 10%, respectively.
[0034] Step six: Place the dissolved solution in a mold and dry it to obtain a composite polyurethane elastomer film at a drying temperature of 100℃.
[0035] The tensile strength curve of the composite polyurethane elastomer is as follows: Figure 1 As shown.
[0036] Example 3 This embodiment provides a hydrogen bond-mediated high-strength composite polyurethane elastomer and its preparation method, specifically including the following steps: Step 1: PTMG2000 and MDI are mixed and heated at 85°C for 4 hours under a nitrogen atmosphere. Deionized water is then added to obtain the prepolymer. The total mass of the prepolymer is 100%, with PTMG2000, MDI, and deionized water comprising 79.4%, 19.9%, and 0.7% of the total mass, respectively.
[0037] Step 2: The prepolymer is heated at 80°C for 16 h to obtain foamed polyurethane.
[0038] Step 3: Dissolve the polyurethane foam in N,N-dimethylacetamide, and then heat at 70°C for 24 h to obtain a viscous liquid product.
[0039] Step four: Dry the obtained viscous product to obtain a polyurethane elastomer substrate.
[0040] Step 5: Dissolve the polyurethane elastomer substrate and dibenzoyl hydrazine in tetrahydrofuran. Specifically, the mass fractions of the polyurethane elastomer substrate and dibenzoyl hydrazine are 94% and 6%, respectively.
[0041] Step six: Place the dissolved solution in a mold and dry it to obtain a composite polyurethane elastomer film at a drying temperature of 80°C.
[0042] The tensile strength curve of the composite polyurethane elastomer is as follows: Figure 1 As shown.
[0043] Example 4 This embodiment provides a hydrogen bond-mediated high-strength composite polyurethane elastomer and its preparation method, specifically including the following steps: Step 1: PTMG2000 and MDI are mixed and heated at 85°C for 4 hours under a nitrogen atmosphere. Deionized water is then added to obtain the prepolymer. The total mass of the prepolymer is 100%, with PTMG2000, MDI, and deionized water comprising 79.4%, 19.9%, and 0.7% of the total mass, respectively.
[0044] Step 2: The prepolymer is heated at 80°C for 12 hours to obtain foamed polyurethane.
[0045] Step 3: Dissolve the polyurethane foam in N,N-dimethylacetamide, and then heat at 70°C for 12 h to obtain a viscous liquid product.
[0046] Step four: Dry the obtained viscous product to obtain a polyurethane elastomer substrate.
[0047] Step 5: Dissolve the polyurethane elastomer substrate and dibenzoyl hydrazine in dimethyl sulfoxide. Specifically, the mass fractions of the polyurethane elastomer substrate and dibenzoyl hydrazine are 80% and 20%, respectively.
[0048] Step six: Place the dissolved solution in a mold and dry it to obtain a composite polyurethane elastomer film at a drying temperature of 80°C.
[0049] The tensile strength curve of the composite polyurethane elastomer is as follows: Figure 1 As shown.
[0050] Example 5 Step 1: The composite polyurethane elastomer film obtained in Example 3 is subjected to a tensile test, then cut into pieces and dissolved in N,N-dimethylacetamide solvent to obtain a composite polyurethane solution.
[0051] Step two: Place the dissolved solution in a mold and dry it to obtain a composite polyurethane elastomer film at a drying temperature of 80℃.
[0052] The tensile strength curve of the composite polyurethane elastomer is as follows: Figure 2 As shown, the results indicate that the recovered composite polyurethane elastomer still possesses high strength.
[0053] In summary, the invention includes, but is not limited to, the above embodiments. Any equivalent substitutions or partial improvements made under the spirit and principles of this invention shall be considered to be within the protection scope of this invention.
Claims
1. A method for preparing a hydrogen-bonded high-strength composite polyurethane elastomer, characterized in that: The method steps include: (1) Under a protective gas atmosphere, polyether polyol and 4,4'-diphenylmethane diisocyanate (MDI) are mixed and reacted at 60~90℃ for 1~6h to obtain a prepolymer. A chemical foaming agent is added to the prepolymer and reacted at 60~80℃ for 3~24h to obtain foamed polyurethane. (2) Dissolve expanded polyurethane in an organic solvent and heat at 30~80℃ for 12~24h to obtain a viscous liquid product. Dry the product to obtain a polyurethane elastomer substrate. (3) Dissolve the polyurethane elastomer substrate and the aromatic small molecule compound in an organic solvent, then pour them into a mold and dry them to obtain a hydrogen bond-mediated high-strength composite polyurethane elastomer. The total mass of polyurethane elastomer substrate and aromatic small molecule compound is 100%, the mass fraction of polyurethane elastomer substrate is 80%~99%, and the mass fraction of aromatic small molecule compound is 1%~20%.
2. The method for preparing a hydrogen-bonded high-strength composite polyurethane elastomer as described in claim 1, characterized in that: In step (1), the polyether polyol is PTMG1000 and / or PTMG2000.
3. The method for preparing a hydrogen-bonded high-strength composite polyurethane elastomer as described in claim 1, characterized in that: The chemical foaming agent is water.
4. The method for preparing a hydrogen-bonded high-strength composite polyurethane elastomer as described in claim 1, 2, or 3, characterized in that: In step (1), the total mass of polyether polyol, MDI and chemical foaming agent is 100%, the mass fraction of polyether polyol is 65.9%~79.4%, the mass fraction of MDI is 19.9%~32.9%, and the mass fraction of chemical foaming agent is 0.7%~1.2%.
5. The method for preparing a hydrogen-bonded high-strength composite polyurethane elastomer as described in claim 1, characterized in that: In step (2), the organic solvent is one or more of N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, and tetrahydrofuran.
6. The method for preparing a hydrogen-bonded high-strength composite polyurethane elastomer as described in claim 1, characterized in that: In step (3), the aromatic small molecule compound is dibenzoylhydrazine and / or diphenylaminourea.
7. The method for preparing a hydrogen-bonded high-strength composite polyurethane elastomer as described in claim 1 or 6, characterized in that: In step (3), the mass fraction of the polyurethane elastomer substrate is 85%~95%, and the mass fraction of the aromatic small molecule compound is 5%~15%.
8. The method for preparing a hydrogen-bonded high-strength composite polyurethane elastomer as described in claim 1, characterized in that: In step (3), the organic solvent is one or more of N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide and tetrahydrofuran.
9. The method for preparing a hydrogen-bonded high-strength composite polyurethane elastomer as described in claim 1, characterized in that: In step (3), the drying temperature is 50~100℃.
10. A hydrogen-bonded mediated high-strength composite polyurethane elastomer, characterized in that: It is prepared by the method described in any one of claims 1 to 9.