Compression-resistant and shear-resistant polyurethane material for expressway bridge support and preparation method of compression-resistant and shear-resistant polyurethane material

Abstract

The invention belongs to the technical field of polyurethane materials, and particularly relates to a compression-resistant and shear-resistant polyurethane material for an expressway bridge support and a preparation method of the compression-resistant and shear-resistant polyurethane material. The water-based polyurethane resin is prepared from a component A and a component B, the component A comprises polyether glycol, a micromolecular chain extender, an anti-hydrolysis agent, a catalyst and an inorganic filler, the component B comprises polyether triol, polyether glycol and diisocyanate, and the polyether glycol is polytetrahydrofuran ether glycol with the number-average molecular weight of 2000g / mol; the polyether trihydric alcohol is polyether trihydric alcohol with the number-average molecular weight of 494 g / mol, and the polyether trihydric alcohol is prepared through a reaction of trimethylolpropane and tetrahydrofuran. According to the invention, polyether triol prepared by reaction of trimethylolpropane and tetrahydrofuran is used as a raw material of the component B, so that the pressure resistance and crystallization resistance of the material can be improved while better shear modulus, mechanical strength, low-temperature flexibility and hydrolysis resistance of the traditional PTMG type polyether are maintained, the use temperature range is enlarged, and the service life of the material is prolonged.

Description

Technical Field

[0001] The invention belongs to the technical field of polyurethane materials, and in particular relates to a compression-resistant and shear-resistant polyurethane material for a highway bridge support and a preparation method thereof. Background Art

[0002] With the vigorous development of infrastructure construction and the continuous improvement of road networks, large bridge structures are indispensable in the construction of highways, so the demand for bridge bearing materials is gradually increasing. At present, the commonly used bearing materials in bridge structures are mostly rubber materials, but traditional rubber materials have poor bearing capacity, are easy to deform, become brittle at low temperatures, and are not resistant to aging, which increases the maintenance cost of bridge structures and poses a hidden danger to highway safety.

[0003] In order to avoid the above problems caused by rubber materials, polyurethane materials have begun to be widely used in road and bridge structures. Polyurethane materials generally have better mechanical properties, low-temperature toughness, aging resistance, and corrosion resistance than rubber materials, and are easy to operate and construct. However, with the high-quality development of road construction, the loss problem caused by the increase in the number of vehicles on the road has gradually increased, and construction units have higher and higher requirements for materials. Conventional polyurethane materials still need to be improved through scientific means to cope with more road conditions. Summary of the invention

[0004] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a compression-resistant and shear-resistant polyurethane material for highway bridge bearings, which comprehensively considers the important role of bridge bearings in highways and the environmental conditions that need to be dealt with, and targets the main role of bridge bearings in road structures. It can minimize the multi-directional deformation factors caused to the material when dealing with oncoming vehicles, and at the same time has the advantages of hydrolysis resistance, high performance, and aging resistance.

[0005] The invention also provides a preparation method thereof, which is cast and formed at room temperature and has a simple operation process.

[0006] The compression-resistant and shear-resistant polyurethane material for highway bridge bearings of the present invention is prepared by a mass ratio of component A to component B of 100:(200-250), wherein component A includes the following raw materials in parts by mass: 46-53 parts of polyether diol; 30-38 parts of small molecule chain extender; 1-2.5 parts of anti-hydrolysis agent; Catalyst 1.8-3.5 parts; 10-16 parts of inorganic filler; Component B includes the following raw materials in parts by weight: 11-20 parts of polyether triol; 52-66 parts of polyether diol; 23-28 parts of diisocyanate; The polyether diol is polytetrahydrofuran ether diol with a number average molecular weight of 2000 g / mol; The polyether triol is a polyether triol with a number average molecular weight of 494 g / mol, which is prepared by reacting trimethylolpropane and tetrahydrofuran.

[0007] The small molecule chain extender is 3,3'-dichloro-4,4'-diaminodiphenylmethane (MOCA).

[0008] The anti-hydrolysis agent is carbodiimide.

[0009] The catalyst is one or more of DXD-07C and DG-02.

[0010] The inorganic filler is silicon micropowder with a mesh size of 400 meshes.

[0011] The preparation method of the polyether triol is as follows: trimethylolpropane is added into a reaction kettle, and after N2 substitution, stirring is started and the temperature is increased, tetrahydrofuran is first added into the reaction kettle to start the reaction, and when the pressure of the kettle drops from 0.3MPa to 0.15MPa, heating is stopped, cooling water is introduced for cooling, tetrahydrofuran is added again, and the reaction temperature is controlled not to exceed 110°C, and when the pressure drop of the kettle is zero, the temperature of the reaction kettle is started to be reduced, and the qualified material is discharged after it drops to room temperature.

[0012] Further, 100 parts by mass of trimethylolpropane were added to the reactor. After N2 replacement, stirring was started and the temperature was raised to 100°C. 40.5 parts by mass of tetrahydrofuran were first added to the reactor to start the reaction. When the reactor pressure dropped from 0.3 MPa to 0.15 MPa, heating was stopped and cooling water was introduced for cooling. 228.5 parts by mass of tetrahydrofuran were added to the reactor and the temperature was controlled not to exceed 110°C for reaction. When the reactor pressure dropped to zero, the reactor was cooled and the qualified material was discharged after it dropped to room temperature.

[0013] The diisocyanate is 2,4-toluene diisocyanate, and the isomer ratio ranges from 96.5 to 98.8%.

[0014] The method for preparing the compression-resistant and shear-resistant polyurethane material for highway bridge bearings of the present invention is prepared by the following steps: (1) Preparation of component A: polyether diol, small molecule chain extender, anti-hydrolysis agent, catalyst and inorganic filler are mixed, stirred evenly by a high-speed disperser at 1000-1500 r / min, and then vacuumed and degassed to obtain component A; (2) Preparation of component B: a polyether triol and a polyether diol with a moisture content of less than 0.05 wt.% are reacted with a diisocyanate at a high temperature to obtain a prepolymer, and then the prepolymer is degassed by vacuum to obtain component B; (3) Mix component A and component B at room temperature, stir evenly using a high-speed stirrer at 500-1500 r / min, vacuum degassing, and pour into a mold, and mature at room temperature for 3-7 days.

[0015] The reaction temperature of the temperature-raising reaction in step (2) is 80-85° C., and the reaction time is 3-4 hours.

[0016] The isocyanate content of the prepolymer in step (2) is 5.5-6.2wt.%.

[0017] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention utilizes the polyether triol prepared by the reaction of trimethylolpropane and tetrahydrofuran as the raw material of component B, which can improve the pressure resistance and anti-crystallization ability of the material while maintaining the good shear modulus, mechanical strength, low temperature flexibility and hydrolysis resistance of the traditional PTMG type polyether, so that the use temperature range of the present invention is increased and the service life is increased.

[0018] 2. The present invention changes the microstructure of the material by adding inorganic filler as the raw material of component A, so that the product has higher strength and rigidity, further improves the overall shear performance of the product, and effectively slows down the deformation of the bridge bearing in the horizontal direction.

[0019] 3. The present invention has a simple manufacturing process, low energy consumption, can be cast and formed at room temperature, is conducive to on-site road construction, can be cured at room temperature on site, and is easy to operate. DETAILED DESCRIPTION

[0020] The present invention will be further described below with reference to the embodiments.

[0021] Unless otherwise specified, all raw materials used in the examples are commercially available or prepared by existing methods. The moisture content of the raw materials described in the examples is less than 0.05wt.%.

[0022] Some raw material parameters in Examples 1-3 and Comparative Examples 1-4 are as follows: PTMG 2000: polyether diol, number average molecular weight 2000 g / mol, functionality 2, Mitsubishi Chemical Corporation; MOCA: small molecule chain extender, 3,3'-dichloro-4,4'-diaminodiphenylmethane, Suzhou Xiangyuan Special Fine Chemical Co., Ltd.; Carbodiimide: anti-hydrolysis agent, Suzhou Keshengtong New Material Technology Co., Ltd.; DXD-07C: catalyst, Shandong Yinuowei Polyurethane Co., Ltd.; DG-02: catalyst, Guangzhou Yourun Synthetic Materials Co., Ltd.; Silicon powder: inorganic non-metallic material, Anhui Green New Materials Technology Co., Ltd.; TMP: trimethylolpropane, Jinan Century Tongda Chemical Co., Ltd.; Tetrahydrofuran: Butene oxide, Jinan Shuangying Chemical Co., Ltd.; DT-100: 2,4-Toluene diisocyanate, Yantai Wanhua Chemical Group Co., Ltd.

[0023] Preparation of polyether triol P305: 100 parts by mass of trimethylolpropane were added to the reactor. After N2 replacement, stirring was started and the temperature was raised to 100°C. 40.5 parts by mass of tetrahydrofuran were first added to the reactor to start the reaction. When the reactor pressure dropped from 0.3MPa to 0.15MPa, heating was stopped and cooling water was introduced for cooling. 228.5 parts by mass of tetrahydrofuran were added to the reactor and the temperature was controlled to react at 107.5±2.5°C. When the reactor pressure dropped to zero, the reactor was cooled down. After it dropped to room temperature, qualified materials were discharged to obtain P305 with a number average molecular weight of 494g / mol and a functionality of 3.

[0024] Example 1 The method for preparing the compression-resistant and shear-resistant polyurethane material for highway bridge bearings is prepared by the following steps: (1) Preparation of component A: 100 parts by mass of component A were mixed with 53 parts of PTMG 2000, 34 parts of MOCA, 1 part of carbodiimide, 1.5 parts of DXD-07C, 0.5 parts of DG-02 and 10 parts of silicon micropowder, and then stirred evenly with a high-speed disperser at 1000 r / min, vacuumed and degassed, and then packaged to obtain component A; (2) Preparation of component B: 100 parts by mass of component B were prepared by mixing 11 parts of P305, 66 parts of PTMG2000 and 23 parts of DT-100 with an isomer ratio of 96.5%, heating to 83°C and reacting for 4 hours to obtain a prepolymer with an isocyanate content of 5.5 wt.%. After vacuum degassing, the prepolymer was packaged to obtain component B. (3) Component A and component B are mixed in a mass ratio of 100:250, stirred evenly using a 500 r / min high-speed stirrer at room temperature, and poured into a mold after vacuum degassing, and aged at room temperature for 3 days.

[0025] Example 2 The method for preparing the compression-resistant and shear-resistant polyurethane material for highway bridge bearings is prepared by the following steps: (1) Preparation of component A: 100 parts by mass of component A were mixed with 46 parts of PTMG 2000, 38 parts of MOCA, 1.5 parts of carbodiimide, 1 part of DXD-07C, 0.8 parts of DG-02 and 12.7 parts of silicon micropowder, and then stirred evenly with a high-speed disperser at 1500 r / min, vacuum-defoamed and packaged to obtain component A; (2) Preparation of component B: 100 parts by mass of component B were mixed with 20 parts of P305, 52 parts of PTMG2000 and 28 parts of DT-100 with an isomer ratio of 98.8%, heated to 80°C, reacted for 3.5 hours, and obtained a prepolymer with an isocyanate content of 6.2 wt.%. After vacuum degassing, the prepolymer was packaged to obtain component B. (3) Component A and component B are mixed in a mass ratio of 100:235, stirred evenly using a 1500 r / min high-speed stirrer at room temperature, and poured into a mold after vacuum degassing, and aged at room temperature for 5 days.

[0026] Example 3 The method for preparing the compression-resistant and shear-resistant polyurethane material for highway bridge bearings is prepared by the following steps: (1) Preparation of component A: 100 parts by mass of component A were mixed with 48 parts of PTMG 2000, 30 parts of MOCA, 2.5 parts of carbodiimide, 2 parts of DXD-07C, 1.5 parts of DG-02 and 16 parts of silicon micropowder, and then stirred evenly with a high-speed disperser at 1300 r / min, vacuumed and degassed, and then packaged to obtain component A; (2) Preparation of component B: 100 parts by mass of component B were mixed with 16 parts of P305, 58 parts of PTMG2000 and 26 parts of DT-100 with an isomer ratio of 97.2%, heated to 85°C, reacted for 3 hours, and obtained a prepolymer with an isocyanate content of 6.0 wt.%. After vacuum degassing, the prepolymer was packaged to obtain component B. (3) Component A and component B are mixed in a mass ratio of 100:200, stirred evenly using a high-speed stirrer at room temperature at 1000 r / min, and poured into a mold after vacuum degassing, and aged at room temperature for 7 days.

[0027] Comparative Example 1 The method for preparing the compression-resistant and shear-resistant polyurethane material for highway bridge bearings is prepared by the following steps: (1) Preparation of component A: 100 parts by mass of component A were mixed with 53 parts of PTMG 2000, 34 parts of MOCA, 1 part of carbodiimide, 1.5 parts of DXD-07C, 0.5 parts of DG-02 and 10 parts of silicon micropowder, and then stirred evenly with a high-speed disperser at 1000 r / min, vacuumed and degassed, and then packaged to obtain component A; (2) Preparation of component B: 100 parts by mass of component B were prepared by mixing 37 parts of PTMG 650 (Mitsubishi Chemical Corporation), 38 parts of PTMG 2000 and 25 parts of DT-100 with an isomer ratio of 97.5%, heating to 85°C and reacting for 3.5 hours to obtain a prepolymer with an isocyanate content of 5.7 wt.%. After vacuum degassing, the prepolymer was packaged to obtain component B. (3) Component A and component B are mixed in a mass ratio of 100:240, stirred evenly using a high-speed stirrer at 800 r / min at room temperature, and poured into a mold after vacuum degassing, and aged at room temperature for 5 days.

[0028] Comparative Example 2 The method for preparing the compression-resistant and shear-resistant polyurethane material for highway bridge bearings is prepared by the following steps: (1) 100 parts by mass of component A, 46 parts of PTMG 2000, 38 parts of MOCA, 1.5 parts of carbodiimide, 1 part of DXD-07C, 0.8 parts of DG-02, and 12.7 parts of silicon micropowder were mixed, and the mixture was stirred evenly with a high-speed disperser at 1500 r / min, vacuumed and degassed, and then packaged to obtain component A; (2) Preparation of component B: 100 parts by mass of component B were mixed with 14 parts of INOVOL C305 (Shandong Yinuowei New Materials Co., Ltd.), 61 parts of PTMG2000 and 25 parts of DT-100 with an isomer ratio of 98.0%, heated to 83°C, reacted for 3.5 hours, and obtained a prepolymer with an isocyanate content of 6.0 wt.%. After vacuum degassing, the prepolymer was packaged to obtain component B. (3) Component A and component B are mixed in a mass ratio of 100:245, stirred evenly using a 1500 r / min high-speed stirrer at room temperature, and poured into a mold after vacuum degassing, and aged at room temperature for 5 days.

[0029] Comparative Example 3 The method for preparing the compression-resistant and shear-resistant polyurethane material for highway bridge bearings is prepared by the following steps: (1) Preparation of component A: 100 parts by mass of component A were mixed with 47 parts of INOVOL C220 (Shandong Yinuowei New Materials Co., Ltd.), 36 parts of MOCA, 2 parts of carbodiimide, 1.5 parts of DXD-07C, 1 part of DG-02 and 12.5 parts of silicon micropowder, and then stirred evenly with a high-speed disperser at 1000 r / min, vacuumed and degassed, and then packaged to obtain component A; (2) Preparation of component B: 100 parts by mass of component B were mixed with 16 parts of P305, 58 parts of PTMG2000 and 26 parts of DT-100 with an isomer ratio of 97.2%, heated to 85°C, reacted for 3 hours, and obtained a prepolymer with an isocyanate content of 6.0 wt.%. After vacuum degassing, the prepolymer was packaged to obtain component B. (3) Component A and component B are mixed in a mass ratio of 100:230, stirred evenly using a high-speed stirrer at room temperature at 1000 r / min, and poured into a mold after vacuum degassing, and aged at room temperature for 7 days.

[0030] Comparative Example 4 The method for preparing the compression-resistant and shear-resistant polyurethane material for highway bridge bearings is prepared by the following steps: (1) Preparation of component A: 100 parts by mass of component A were mixed with 48 parts of PTMG 2000, 30 parts of MOCA, 2.5 parts of carbodiimide, 2 parts of DXD-07C, 1.5 parts of DG-02 and 16 parts of silicon micropowder, and then stirred evenly with a high-speed disperser at 1300 r / min, vacuumed and degassed, and then packaged to obtain component A; (2) Preparation of component B: 100 parts by mass of component B were mixed with 10 parts of P304, 65 parts of PTMG2000 and 25 parts of DT-100 with an isomer ratio of 97%, heated to 85°C, reacted for 4 hours, and a prepolymer with an isocyanate content of 5.74% was obtained. After vacuum degassing, the prepolymer was packaged to obtain component B. The preparation method of P304 is as follows: 100g of trimethylolpropane is added to a reactor, and after N2 replacement, stirring is started and the temperature is raised to 100°C, 24.2g of tetrahydrofuran is first added to the reactor to start the reaction, and when the reactor pressure drops from 0.3MPa to 0.15MPa, heating is stopped, and cooling water is introduced for cooling, 137g of tetrahydrofuran is added to the reactor, and the temperature is controlled not to exceed 110°C, and the reaction is carried out at 105°C. When the reactor pressure drop is zero, the reactor is cooled, and the material is discharged after it drops to room temperature. The number average molecular weight of the obtained polyether triol P304 is 350g / mol, and the functionality is 3.

[0031] (3) Component A and component B are mixed in a mass ratio of 100:210, stirred evenly using a high-speed stirrer at room temperature at 1000 r / min, and poured into a mold after vacuum degassing, and aged at room temperature for 3 days.

[0032] Performance Testing The performance of Examples 1-3 and Comparative Examples 1-4 was tested according to the following standards, and the results are shown in Table 1 below.

[0033] Hardness: GB / T531-1999; Tensile strength and elongation at break: GB / T528-2009; Compression set (70°C, 20h): GB / T7759, A1 type specimen; Shear modulus: GB / T20688.1; Tensile strength after water resistance (70°C, 24h): GB / T15905-1995; Brittle temperature: GB / T15256.

[0034] Table 1 Performance test table of Examples 1-3 and Comparative Examples 1-4

[0035] Comparison of Examples 1-3 with Comparative Examples 1, 2, and 4 shows that the introduction of P305 not only makes the bridge bearing have excellent comprehensive mechanical properties and water resistance, but also makes the new product better able to resist longitudinal deformation and transverse shear deformation from bridge road vehicle pressure. The main reason is that P305 not only retains the advantages of high mechanical properties, hydrolysis resistance, and aging resistance brought by PTMG type polyether to the product, but also improves the constant compression performance of the product due to its increased functionality.

[0036] Compared with Comparative Example 1, Examples 1-3 have smaller compression set and better low temperature compliance, which is because P305 has higher functionality than PTMG650 and makes the microscopic chemical structure of the product more asymmetric. Comparative Example 1 has only a higher shear modulus than Examples 1-3, which is presumably because the molecular chains of PTMG650 have better arrangement and orientation than P305.

[0037] Compared with Comparative Example 2, Examples 1-3 have greater advantages in longitudinal tensile strength, transverse shear performance and hydrolysis resistance, mainly because P305 in Examples 1-3 retains some regularity of PTMG-type molecular chains compared to conventional trifunctional PPG polyethers.

[0038] Compared with Comparative Example 3, Examples 1-3 have excellent tensile properties and water resistance, and the shear performance is also relatively high. This is because Examples 1-3 use PTMG2000 in material A while Comparative Example 3 uses PPG polyether C220. PTMG-type products have better mechanical properties and stronger water resistance due to their special molecular chain structure.

[0039] Compared with Comparative Example 4, Examples 1-3 have higher elongation at break and enhanced ability to resist lateral deformation, mainly because: compared with P305 in Example 4 and P304 used in Material B, the trimethylolpropane used in the synthesis of P304 accounts for a higher proportion, and its molecular weight is also reduced. In this system, the influence of PTMG is reduced, and thus a more obvious decrease in elongation and shear modulus of the finished product is shown.

[0040] Based on the above conclusions, the present invention has the advantages of good resistance to longitudinal pressure and transverse shear force, and at the same time has excellent mechanical properties, good hydrolysis resistance and low-temperature compliance. It can be well applied to highway bridge bearing materials to better cope with the road environment.

Claims

1. A compression-resistant and shear-resistant polyurethane material for highway bridge bearings, characterized in that: The mass ratio of component A to component B is 100: (200-250), and component A includes the following raw materials in parts by mass: 46-53 parts of polyether diol; 30-38 parts of small molecule chain extender; 1-2.5 parts of anti-hydrolysis agent; Catalyst 1.8-3.5 parts; 10-16 parts of inorganic filler; Component B includes the following raw materials in parts by weight: Polyether triol 11-20 parts; 52-66 parts of polyether diol; 23-28 parts of diisocyanate; The polyether diol is polytetrahydrofuran ether diol with a number average molecular weight of 2000 g / mol; The polyether triol is a polyether triol with a number average molecular weight of 494 g / mol, which is prepared by reacting trimethylolpropane and tetrahydrofuran.

2. The compression-resistant and shear-resistant polyurethane material for highway bridge bearings according to claim 1 is characterized in that: The small molecule chain extender is 3,3'-dichloro-4,4'-diaminodiphenylmethane.

3. The compression-resistant and shear-resistant polyurethane material for highway bridge bearings according to claim 1 is characterized in that: The anti-hydrolysis agent is carbodiimide.

4. The compression-resistant and shear-resistant polyurethane material for highway bridge bearings according to claim 1, characterized in that: The catalyst is one or more of DXD-07C and DG-02.

5. The compression-resistant and shear-resistant polyurethane material for highway bridge bearings according to claim 1, characterized in that: The inorganic filler is silicon powder.

6. The compression-resistant and shear-resistant polyurethane material for highway bridge bearings according to claim 1, characterized in that: The preparation method of the polyether triol is as follows: trimethylolpropane is added into a reaction kettle, and after N2 substitution, stirring is started and the temperature is increased, tetrahydrofuran is first added into the reaction kettle to start the reaction, and when the pressure of the kettle drops from 0.3MPa to 0.15MPa, heating is stopped, cooling water is introduced for cooling, tetrahydrofuran is added again, and the reaction temperature is controlled not to exceed 110°C, and when the pressure drop of the kettle is zero, the temperature of the reaction kettle is started to be reduced, and the qualified material is discharged after it drops to room temperature.

7. The compression-resistant and shear-resistant polyurethane material for highway bridge bearings according to claim 1, characterized in that: The diisocyanate is 2,4-toluene diisocyanate, and the isomer ratio ranges from 96.5 to 98.8%.

8. A method for preparing the compression-resistant and shear-resistant polyurethane material for highway bridge bearings according to any one of claims 1 to 7, characterized in that: Prepared by the following steps: (1) Preparation of component A: polyether diol, small molecule chain extender, anti-hydrolysis agent, catalyst and inorganic filler are mixed, and then vacuum degassing is performed to obtain component A; (2) Preparation of component B: reacting polyether triol, polyether diol and diisocyanate at elevated temperature to obtain a prepolymer, and then vacuum degassing to obtain component B; (3) Mix component A and component B at room temperature, stir evenly, vacuum and degas, pour into the mold, and mature at room temperature for 3-7 days.

9. The method for preparing the compression-resistant and shear-resistant polyurethane material for highway bridge bearings according to claim 8, characterized in that: The reaction temperature of the temperature-raising reaction in step (2) is 80-85° C., and the reaction time is 3-4 hours.

10. The method for preparing the compression-resistant and shear-resistant polyurethane material for highway bridge bearings according to claim 8, characterized in that: The isocyanate content of the prepolymer in step (2) is 5.5-6.2wt.%.

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