Polyurethane adhesive for road paving and preparation method thereof

Abstract

A polyurethane adhesive for road paving comprises the following components in parts by weight: prepolymer A, 15-30; prepolymer B, 10-30; prepolymer C, 5-20; diluent, 14-26; stabilizer, 0.01-0.1; wherein prepolymer A is a prepolymer of polyether polyol and toluene diisocyanate; prepolymer B is a prepolymer of vegetable oil polyol and diphenylmethane diisocyanate; prepolymer C is a prepolymer of long-chain fatty monool and polymethylene polyphenyl isocyanate. The preparation method is simple. When the polyurethane adhesive is mixed with aggregate to prepare polyurethane concrete, the obtained polyurethane concrete has a long construction open time, high splitting strength, high dynamic stability, and high low-temperature bending strain.

Description

Technical Field

[0001] The invention belongs to the field of road materials, and in particular relates to a polyurethane adhesive for road paving and a preparation method thereof. Background Art

[0002] With the rapid development of my country's economy and society, the mileage of highways, first-class highways, second-class highways and other highways has increased, and the traffic volume has also increased sharply, which has put forward higher requirements on the performance of highway materials. At present, the construction of highway pavement mainly uses two types of materials, asphalt and cement, in combination with aggregate fillers. Asphalt materials are mainly used to build highways and first-class highway pavements. However, years of use experience have shown that asphalt pavements have the problem of rutting in high temperatures in summer and brittle cracking in winter due to cold weather. Although cement pavements are relatively low in cost, they have the disadvantages of low flatness, shrinkage and cracking in winter, poor stability when exposed to water, high tire noise, and long open traffic time. They are generally used on second-class and lower highways.

[0003] In order to solve the problems existing in asphalt and cement pavements, new binders such as acrylates, epoxies, phenolic resins, and polyurethanes have emerged in an endless stream in recent years, among which polyurethane has become a research hotspot due to its excellent designability. It takes into account both strength and toughness by adjusting the ratio of soft and hard segments in the molecular structure, has good adhesion, and outstanding high and low temperature resistance. CN 108751841 A discloses a polyurethane resin permeable pavement material and a preparation method thereof, which utilizes a two-component polyurethane-acrylate adhesive and is mixed with aggregate to obtain a permeable pavement with excellent strength, flexibility, friction resistance, and water permeability, but its operation and construction are relatively complicated, and the construction open period is short. CN 106854450 A discloses a solvent-free one-component polyurethane adhesive for gravel permeable pavement and a preparation method thereof, which provides an environmentally friendly adhesive, and uses a silane coupling agent and a latent curing agent to solve the problem of bubble generation and slow curing speed during curing. The patent uses expensive silane coupling agents and latent curing agents, which is not conducive to large-scale promotion. CN 111138116 A discloses a polyether polyurethane concrete paving material and a preparation method thereof, which provides a polyether single-component polyurethane, which also adopts a latent curing agent to reduce the solidification expansion phenomenon of polyurethane concrete. When preparing concrete, a latent curing agent needs to be added, which is troublesome to operate and has low economy.

[0004] In summary, when current polyurethane materials are used on pavement, the construction is complex, the construction opening period is short, the price is high, and the economy is poor, and they are not suitable for large-scale promotion. Summary of the invention

[0005] The first object of the present invention is to provide a polyurethane adhesive for road paving, which is easy to construct and can form polyurethane concrete with a long construction open period, high splitting strength, and good high and low temperature resistance after being mixed with aggregate, so that the application of polyurethane concrete breaks through the transportation distance limitation and is suitable for large-scale promotion;

[0006] The second object of the present invention is to provide a preparation method using the above-mentioned polyurethane adhesive, which is simple and easy to operate.

[0007] To achieve the first object of the present invention, the following technical solutions are adopted:

[0008] A polyurethane adhesive for road paving, comprising the following components in parts by weight:

[0009] in,

[0010] The prepolymer A is a prepolymer of polyether polyol and toluene diisocyanate;

[0011] The prepolymer B is a prepolymer of vegetable oil polyol and diphenylmethane diisocyanate;

[0012] The prepolymer C is a prepolymer of long-chain fatty monoalcohol and polymethylene polyphenyl isocyanate.

[0013] The polyurethane adhesive of the present invention has a long construction open period; after being mixed with aggregates, it can form polyurethane concrete with a long construction open period, high splitting strength, and good high and low temperature resistance. The construction open period can reach up to 8 hours, so that the application of polyurethane concrete breaks through the transportation distance limitation.

[0014] In one embodiment, in the polyurethane adhesive, the sum of the weight parts of each component is 100.

[0015] In one embodiment, in the prepolymer A, the content of NCO end groups is 2-8 wt%, such as 3 wt%, 4 wt%, 5 wt%, 6 wt% and 7 wt%.

[0016] In one embodiment, in the prepolymer raw material of the prepolymer A, the functionality of the polyether polyol is 2-3, such as 2 and 3; preferably its molecular weight is 600-4000, such as 800, 1000, 1200, 1400, 1600, 1800, 2000, 2200, 2400, 2600, 2800, 3000, 3200, 3400, 3600 and 3800; and / or

[0017] In the prepolymer raw material of the prepolymer A, the toluene diisocyanate includes any one or more combinations of TDI-80, TDI-65 and TDI-100.

[0018] In one embodiment, in the prepolymer B, the content of NCO end groups is 3-9wt%, such as 4wt%, 5wt%, 6wt%, 7wt% and 8wt%.

[0019] In one embodiment, in the prepolymer raw material of the prepolymer B, the vegetable oil polyol includes castor oil polyol and / or soybean oil polyol; and / or

[0020] In the prepolymer raw material of the prepolymer B, the diphenylmethane diisocyanate includes any one or more combinations of MDI-100, MDI-50 and MDI-10.

[0021] In one embodiment, in the prepolymer C, the content of NCO end groups is 0.1-5wt%, such as 0.2wt%, 0.4wt%, 0.6wt%, 0.8wt%, 1.0wt%, 2.2wt%, 2.4wt%, 2.6wt%, 2.8wt%, 3.0wt%, 3.2wt%, 3.4wt%, 3.6wt%, 3.8wt%, 4.0wt%, 4.2wt%, 4.4wt%, 4.6wt% and 4.8wt%.

[0022] In one embodiment, in the prepolymer raw material of the prepolymer C, the long-chain fatty monoalcohol includes any one or more of n-decanol, lauryl alcohol and myristyl alcohol; and / or

[0023] In the prepolymer raw material of the prepolymer C, the polymethylene polyphenyl isocyanate includes any one or more combinations of PM-130, PM-200 and PM-400.

[0024] In one embodiment, the diluent includes MDI-6001 and / or any one or more of dimethyl carbonate, propylene carbonate and ethyl acetate;

[0025] Preferably, the diluent is a mixture of MDI-6001 and dimethyl carbonate, and the content of MDI-6001 is 20-80wt%, such as 25wt%, 30wt%, 35wt%, 40wt%, 45wt%, 50wt%, 55wt%, 60wt%, 65wt%, 70wt% and 75wt%.

[0026] In one embodiment, the stabilizer includes any one or more combinations of benzoyl chloride, adipoyl chloride and 3,5-dimethylbenzoyl chloride.

[0027] In one embodiment, in the polyurethane adhesive, the content of the stabilizer is 0.01-0.1wt%, such as 0.02wt%, 0.03wt%, 0.04wt%, 0.05wt%, 0.06wt%, 0.07wt%, 0.08wt% and 0.09wt%.

[0028] To achieve the second object, the present invention also provides a method for preparing the aforementioned polyurethane adhesive.

[0029] In one embodiment, the preparation method comprises the following steps:

[0030] (1) mixing the prepolymer A, the prepolymer B and the prepolymer C once to obtain a primary mixture;

[0031] (2) adding the diluent to the obtained primary mixture for secondary mixing to obtain a secondary mixture;

[0032] (3) Adding the stabilizer to the obtained secondary mixture and mixing for a third time to obtain a third mixture, i.e., a polyurethane adhesive for road paving.

[0033] Those skilled in the art understand that, since the prepolymer A is a prepolymer of polyether polyol and toluene diisocyanate, the prepolymer A is obtained by a synthesis reaction of polyether polyol and toluene diisocyanate. In one embodiment, in the synthesis reaction of synthesizing the prepolymer A, the reaction temperature is 70°C-90°C, such as 72°C, 74°C, 76°C, 78°C, 80°C, 82°C, 84°C, 86°C and 88°C; preferably, the reaction time is 3-6h, such as 3.5h, 4h, 4.5h, 5h and 5.5h; preferably, the molar ratio of the polyether polyol to the toluene diisocyanate is 1:(1.21-5.80), such as 1:1.6, 1:2.0, 1:2.4, 1:2.8, 1:3.2, 1:3.6, 1:4.0, 1:4.4, 1:4.8, 1:5.2, 1:5.4.

[0034] Those skilled in the art understand that, since the prepolymer B is a prepolymer of vegetable oil polyol and diphenylmethane diisocyanate, the prepolymer B is obtained by a synthesis reaction between the vegetable oil polyol and diphenylmethane diisocyanate. In one embodiment, in the synthesis reaction of synthesizing the prepolymer B, the reaction temperature is 70°C-90°C, such as 72°C, 74°C, 76°C, 78°C, 80°C, 82°C, 84°C, 86°C and 88°C; preferably, the reaction time is 2-4h, such as 2.5h, 3h and 3.5h; preferably, the mass ratio of the vegetable oil polyol to the diphenylmethane diisocyanate is 1:(0.34-0.86), such as 1:0.39, 1:0.44, 1:0.49, 1:0.54, 1:0.59, 1:0.64, 1:0.69, 1:0.74, 1:0.79 and 1:0.84.

[0035] Since the prepolymer C is a prepolymer of a long-chain fatty monoalcohol and polymethylene polyphenyl isocyanate, the prepolymer C is obtained by a synthesis reaction between the long-chain fatty monoalcohol and polymethylene polyphenyl isocyanate. In one embodiment, in the synthesis reaction of synthesizing the prepolymer C, the reaction temperature is 70°C-90°C, such as 72°C, 74°C, 76°C, 78°C, 80°C, 82°C, 84°C, 86°C and 88°C; preferably, the reaction time is 2-4h, such as 2.5h, 3h and 3.5h; preferably, the mass ratio of the long-chain fatty alcohol to the polymethylene polyphenyl isocyanate is 1:(0.64-1.22), such as 1:0.68, 1:0.72, 1:0.76, 1:0.80, 1:0.84, 1:0.88, 1:1.92, 1:0.96, 1:1.00, 1:1.04, 1:1.08, 1:1.12, 1:1.16 and 1:1.20.

[0036] In one embodiment, in step (1), the mixing temperature of the primary mixing is 70-90°C, such as 72°C, 74°C, 76°C, 78°C, 80°C, 82°C, 84°C, 86°C and 88°C; the mixing time is 0.5-1.5h, such as 0.6h, 0.7h, 0.8h, 0.9h, 1.0h, 1.1h, 1.2h, 1.3h and 1.4h.

[0037] In one embodiment, in step (2), the mixing temperature of the secondary mixing is 40-60°C, such as 42°C, 44°C, 46°C, 48°C, 50°C, 52°C, 54°C, 56°C and 58°C; the mixing time is 20-40min, such as 25min, 30min and 35min.

[0038] In one embodiment, in step (3), the mixing temperature of the three mixings is 20-40°C, such as 22°C, 24°C, 26°C, 28°C, 30°C, 32°C, 34°C, 36°C and 38°C; the mixing time is 20-40min, such as 25min, 30min and 35min.

[0039] The present invention also provides a polyurethane concrete, the preparation raw materials of which include a polyurethane adhesive and aggregates, wherein the polyurethane adhesive is the aforementioned polyurethane adhesive and the polyurethane adhesive prepared by the aforementioned preparation method.

[0040] The present invention also provides the above-mentioned polyurethane adhesive and the use of the polyurethane adhesive prepared by the above-mentioned preparation method in the preparation of polyurethane concrete.

[0041] The beneficial effects of the present invention are:

[0042] The polyurethane adhesive for road paving of the present invention has a long construction open period; after being mixed with aggregates, it can form a polyurethane concrete with a long construction open period, high splitting strength and good high and low temperature resistance, and the construction open period can be up to 8 hours, so that the application of the polyurethane concrete breaks through the transportation distance limitation; specifically, by designing its formula, the reaction activity of the NCO group in the obtained polyurethane adhesive with water is reduced; the introduction of the prepolymer of hydrophobic vegetable oil polyol and diphenylmethane diisocyanate reduces the diffusion speed of moisture in the adhesive, and the two form a synergistic effect, solving the problem that the single-component moisture-curing polyurethane adhesive has a short construction open period. The invention solves the problem that the maximum construction open period can reach 8 hours; the prepolymer of long-chain fatty monoalcohol and polymethylene polyphenyl isocyanate is introduced to improve the solubility of polymethylene polyphenyl isocyanate in the mixed prepolymer, and solves the problem that polymethylene polyphenyl isocyanate is prone to turbidity when mixed with other prepolymers; the obtained polyurethane adhesive has low viscosity, is easy to mix with aggregates, and is simple to construct; when the polyurethane adhesive of the invention is mixed with aggregates to prepare polyurethane concrete, the construction open period of the obtained polyurethane concrete can reach 8 hours, the splitting strength can reach more than 4.5MPa, the dynamic stability exceeds 100,000 times / mm, and the low-temperature bending strain can reach 7600με;

[0043] The preparation method of the polyurethane adhesive of the present invention is simple and easy to operate. DETAILED DESCRIPTION

[0044] The technical scheme and its effects of the present invention are further described below in conjunction with specific implementation methods / examples. The following implementation methods / examples are only used to illustrate the content of the present invention, and the invention is not limited to the following implementation methods or examples. Simple changes made to the present invention using the concept of the present invention are all within the scope of protection claimed by the present invention.

[0045] The raw material sources of the raw materials used in the following examples / comparative examples are:

[0046] Polyether polyol with a molecular weight of 600 and a functionality of 2, from Jiangsu Haian Petrochemical, brand HSH-206;

[0047] Polyether polyol with a molecular weight of 4000 and a functionality of 2, Wanhua Chemical, brand name Wanol C2040D;

[0048] Polyether polyol with a molecular weight of 1000 and a functionality of 2, Wanhua Chemical, brand name Wanol C2010;

[0049] Polyether polyol with a molecular weight of 2000 and a functionality of 2, Wanhua Chemical, brand name Wanol C2020;

[0050] TDI-80, Wanhua Chemical, brand name Wannate TDI-80;

[0051] TDI-100, Wanhua Chemical, brand name Wannate TDI-100;

[0052] TDI-65, Wanhua Chemical, brand name Wannate TDI-65;

[0053] Castor oil polyol, Yuci Jinhu Oil Factory, first-grade castor oil, purity ≥99.6%;

[0054] Soybean oil polyol, Nantong Haierma Technology Co., Ltd., brand HM-10100;

[0055] MDI-100, Wanhua Chemical, brand name Wannate MDI-100;

[0056] MDI-50, Wanhua Chemical, brand name Wannate MDI-50;

[0057] MDI-10, Wanhua Chemical, brand name Wannate MDI-10;

[0058] n-Decanol, produced by Jiangsu Haiqi International Co., Ltd., industrial grade;

[0059] Lauryl alcohol, produced by Jiangsu Haiqi International Co., Ltd., industrial grade;

[0060] Myristyl alcohol, produced by Jiangsu Haiqi International Co., Ltd., industrial grade;

[0061] PM-130, Wanhua Chemical, brand name Wannate PM-130;

[0062] PM-200, Wanhua Chemical, brand name Wannate PM-200;

[0063] PM-400, Wanhua Chemical, brand name Wannate PM-400;

[0064] MDI-6001, Wanhua Chemical, brand name Wannate MDI-6001;

[0065] Dimethyl carbonate, Jinan Linhai Chemical, industrial grade;

[0066] 3,5-Dimethylbenzoyl chloride, Taizhou Hongxing Chemical Co., Ltd., industrial grade;

[0067] Benzoyl chloride, Taizhou Hongxing Chemical Co., Ltd., industrial grade.

[0068] Polyurethane adhesive E, produced by Wanhua Chemical Group Co., Ltd., brand name Wannate 6170F;

[0069] AC-13 type dense graded aggregate, the gradation type specified in "JTG F40-2004 Technical Specifications for Highway Asphalt Pavement Construction".

[0070] Test method / standard:

[0071] Open time: After mixing the polyurethane adhesive with the aggregate, place it in an environment with a temperature of 30°C and a relative humidity of 80%, and perform Marshall specimen molding every half an hour. The molding reference standard is T0702 in the "JTG E20-2011 Test Procedure for Asphalt and Asphalt Mixtures for Highway Engineering", and the time corresponding to the thickness of the Marshall specimen reaching 67.5mm is the open time;

[0072] Splitting strength, "JTG E20-2011 Test Procedure for Asphalt and Asphalt Mixtures in Highway Engineering" T0716;

[0073] Dynamic stability, "JTG E20-2011 Highway Engineering Asphalt and Asphalt Mixture Test Procedure" T0719;

[0074] Low temperature bending strain, "JTG E20-2011 Test Procedure for Asphalt and Asphalt Mixtures in Highway Engineering" T0715.

[0075] Example 1 (S1)

[0076] The polyurethane adhesive D1 for road paving was prepared according to the following preparation method, which specifically includes the following steps:

[0077] (1) 510 g of a polyether polyol (polyether polyol) having a molecular weight of 600 and a functionality of 2 and 180 g of TDI-80 (toluene diisocyanate) were reacted at 80° C. in a nitrogen atmosphere for 3 h to prepare a prepolymer A1; in the prepolymer A1, the molar ratio of the polyether polyol to TDI-80 was 1:1.21, and the content of the NCO terminal group was 2 wt %;

[0078] (2) 600 g of castor oil polyol (vegetable oil polyol) and 300 g of MDI-100 (diphenylmethane diisocyanate) were reacted at 80° C. in a nitrogen atmosphere for 2 h to prepare a prepolymer B1; in the prepolymer B1, the content of NCO end groups was 3 wt %;

[0079] (3) 400 g of n-decanol (long-chain fatty monoalcohol) and 346 g of PM-130 (polymethylene polyphenyl isocyanate) were reacted at 80° C. in a nitrogen atmosphere for 2 h to obtain prepolymer C1; in prepolymer C1, the content of NCO end groups was 0.1 wt %;

[0080] (4) mixing 150 g of the prepolymer A1, 100 g of the prepolymer B1 and 50 g of the prepolymer C1 at 80° C. for 1 h (the primary mixing) to obtain a primary mixture;

[0081] (5) lowering the temperature to 50° C., adding 260 g of a diluent to the obtained primary mixture, and continuing mixing at 50° C. for 30 min (the secondary mixing) to obtain a secondary mixture; wherein the diluent is a mixture of MDI-6001 and dimethyl carbonate, and the content of MDI-6001 is 20 wt %;

[0082] (6) The temperature was lowered to 40° C., 0.3 g of 3,5-dimethylbenzoyl chloride (stabilizer) was added to the obtained secondary mixture, and the mixture was mixed at 40° C. for 20 min (the third mixing) to obtain a third mixture, i.e., the polyurethane adhesive D1 for road paving.

[0083] Embodiment 2 (S2)

[0084] The polyurethane adhesive D2 for road paving was prepared according to the preparation method of Example 1, and compared with Example 1, the only differences were as follows:

[0085] In step (1), the polyether polyol used is 600 g of a polyether polyol having a molecular weight of 4000 and a functionality of 2; the toluene diisocyanate used is 150 g of TDI-100; a prepolymer A2 is prepared; in the prepolymer A2, the molar ratio of the polyether polyol to TDI-100 is 1:5.80, and the content of the NCO end group is 8 wt%;

[0086] In step (2), the vegetable oil polyol is 600 g soybean oil polyol; the diphenylmethane diisocyanate is 262 g MDI-50; a prepolymer B2 is obtained; in the prepolymer B2, the content of NCO end groups is 5 wt%;

[0087] In step (3), the long-chain fatty alcohol is 400g of lauryl alcohol; the polymethylene polyphenyl isocyanate is 425g of PM-200; the prepolymer C2 is obtained; in the prepolymer C2, the content of NCO end groups is 5wt%;

[0088] In step (4), 300 g of the prepolymer A2, 300 g of the prepolymer B2 and 200 g of the prepolymer C2 are mixed once;

[0089] In step (5), the amount of the diluent added is 140 g; the diluent is a mixture of MDI-6001 and dimethyl carbonate, wherein the content of MDI-6001 is 80 wt %;

[0090] In step (6), the amount of the stabilizer added is 0.4 g;

[0091] The polyurethane adhesive D2 for road paving was prepared.

[0092] Embodiment 3 (S3)

[0093] The polyurethane adhesive D3 for road paving was prepared according to the preparation method of Example 1, and compared with Example 1, the only differences were as follows:

[0094] In step (1), the polyether polyol used is 500 g of a polyether polyol having a molecular weight of 1000 and a functionality of 2; the toluene diisocyanate used is 141 g of TDI-65; a prepolymer A3 is prepared; in the prepolymer A3, the molar ratio of the polyether polyol to TDI-65 is 1:1.62, and the content of the NCO end group is 4 wt%;

[0095] In step (2), the vegetable oil polyol is 600g of castor oil polyol; the diphenylmethane diisocyanate is 517g of MDI-50; a prepolymer B3 is obtained; in the prepolymer B3, the content of NCO end groups is 9wt%;

[0096] In step (3), the long-chain fatty alcohol is 400 g of myristyl alcohol; the polymethylene polyphenyl isocyanate is 298 g of PM-400; a prepolymer C3 is obtained; in the prepolymer C3, the content of NCO end groups is 2 wt%;

[0097] In step (4), 200 g of the prepolymer A3, 250 g of the prepolymer B3 and 100 g of the prepolymer C3 are mixed once;

[0098] In step (5), the amount of the diluent added is 200 g; the diluent is a mixture of MDI-6001 and dimethyl carbonate, wherein the content of MDI-6001 is 40 wt %;

[0099] In step (6), the amount of the stabilizer added is 1 g;

[0100] The polyurethane adhesive D3 for road paving was prepared.

[0101] Embodiment 4 (S4)

[0102] The polyurethane adhesive D4 for road paving was prepared according to the preparation method of Example 1, and compared with Example 1, the only differences were as follows:

[0103] In step (1), the polyether polyol used is 650 g of a polyether polyol having a molecular weight of 2000 and a functionality of 2; the toluene diisocyanate used is 158 g of TDI-80; a prepolymer A4 is prepared; in the prepolymer A4, the molar ratio of the polyether polyol to TDI-80 is 1:2.79, and the content of the NCO end group is 6 wt%;

[0104] In step (2), the vegetable oil polyol is 600 g soybean oil polyol, and the diphenylmethane diisocyanate is 327 g MDI-10; a prepolymer B4 is obtained; in the prepolymer B4, the content of NCO end groups is 7 wt%;

[0105] In step (3), the long-chain fatty alcohol is 400 g of myristyl alcohol; the polymethylene polyphenyl isocyanate is 350 g of PM-200; the prepolymer C4 is obtained; in the prepolymer C4, the content of NCO end groups is 4 wt%;

[0106] In step (4), 250 g of the prepolymer A4, 150 g of the prepolymer B4 and 160 g of the prepolymer C4 are mixed once;

[0107] In step (5), the amount of the diluent added is 220 g; the diluent is a mixture of MDI-6001 and dimethyl carbonate, wherein the content of MDI-6001 is 60 wt %;

[0108] In step (6), the amount of the stabilizer added is 0.1 g;

[0109] The polyurethane adhesive D4 for road paving was prepared.

[0110] Embodiment 5 (S5)

[0111] The polyurethane adhesive D5 for road paving was prepared according to the preparation method of Example 1, and compared with Example 1, the only differences were as follows:

[0112] In step (5), the diluent is MDI-6001;

[0113] The polyurethane adhesive D5 for road paving was prepared.

[0114] Embodiment 6 (S6)

[0115] The polyurethane adhesive D6 for road paving was prepared according to the preparation method of Example 1, and compared with Example 1, the only differences were as follows:

[0116] In step (6), the stabilizer is benzoyl chloride;

[0117] The polyurethane adhesive D6 for road paving was prepared.

[0118] Performance test and test results

[0119] The polyurethane adhesives D1-6 and E prepared in Examples 1-6 were mixed with AC-13 type dense graded aggregate at a binder-to-cement ratio of 5.0 wt % to prepare concrete, and S95 grade mineral powder was used to fill the voids in the obtained concrete to obtain polyurethane concretes F1-6 and F1'.

[0120] The obtained polyurethane concrete F1-6 and F1' were subjected to relevant performance tests, including construction open time, splitting strength, dynamic stability and low temperature bending strain, etc. The test results are shown in Table 1.

[0121] Table 1 Test results of relevant properties of polyurethane concrete F1-6 and F1'

[0122] sample F1 F2 F3 F4 F5 F6 F1’ Construction opening hours / h 6.5 7.5 6 8 6.5 7 3 Splitting strength / MPa 4.5 4.8 4.8 4.6 4.7 4.7 4.0 Dynamic stability / times / mm 102310 127100 104920 113400 104340 116760 45300 Low temperature bending strain / με 4020 7600 6400 5300 5730 6290 3500

[0123] According to the performance test results in Table 1:

[0124] The polyurethane concrete prepared by mixing the polyurethane adhesive obtained by the invention with aggregate has a long construction open time, high splitting strength, high dynamic stability and high low-temperature bending strain.

Claims

1. A polyurethane adhesive for road paving, characterized in that: The polyurethane adhesive comprises the following components in parts by weight: The prepolymer A is a prepolymer of polyether polyol and toluene diisocyanate; The prepolymer B is a prepolymer of vegetable oil polyol and diphenylmethane diisocyanate; The prepolymer C is a prepolymer of long-chain fatty monoalcohol and polymethylene polyphenyl isocyanate.

2. The polyurethane adhesive according to claim 1, characterized in that: In the prepolymer A, the content of NCO terminal groups is 2-8 wt %.

3. The polyurethane adhesive according to claim 2, characterized in that: In the prepolymer raw material of the prepolymer A, the functionality of the polyether polyol is 2-3; and / or In the prepolymer raw material of the prepolymer A, the toluene diisocyanate includes any one or more combinations of TDI-80, TDI-65, and TDI-100.

4. The polyurethane adhesive according to claim 3, characterized in that: In the prepolymer raw material of the prepolymer A, the molecular weight of the polyether polyol is 600-4000.

5. The polyurethane adhesive according to any one of claims 1 to 4, characterized in that: In the prepolymer B, the content of NCO terminal groups is 3-9 wt %.

6. The polyurethane adhesive according to claim 5, characterized in that: In the prepolymer raw material of the prepolymer B, the vegetable oil polyol includes castor oil polyol and / or soybean oil polyol; and / or In the prepolymer raw material of the prepolymer B, the diphenylmethane diisocyanate includes any one or more combinations of MDI-100, MDI-50 and MDI-10.

7. The polyurethane adhesive according to any one of claims 1 to 4 and 6, characterized in that: In the prepolymer C, the content of NCO terminal groups is 0.1-5 wt %.

8. The polyurethane adhesive according to claim 7, characterized in that: In the prepolymer raw material of the prepolymer C, the long-chain fatty monoalcohol includes any one or more of n-decyl alcohol, lauryl alcohol and myristyl alcohol; and / or In the prepolymer raw material of the prepolymer C, the polymethylene polyphenyl isocyanate includes any one or more combinations of PM-130, PM-200 and PM-400.

9. The polyurethane adhesive according to any one of claims 1 to 4, 6 and 8, characterized in that: The diluent includes MDI-6001 and / or any one or more combinations of dimethyl carbonate, propylene carbonate and ethyl acetate.

10. The polyurethane adhesive according to claim 9, characterized in that: The diluent is a mixture of MDI-6001 and dimethyl carbonate, wherein the content of MDI-6001 is 20-80wt%.

11. The polyurethane adhesive according to any one of claims 1 to 4, 6, 8 and 10, characterized in that: The stabilizer includes any one or more combinations of benzoyl chloride, adipoyl chloride and 3,5-dimethylbenzoyl chloride.

12. The polyurethane adhesive according to claim 11, characterized in that: In the polyurethane adhesive, the content of the stabilizer is 0.01-0.1wt%.

13. A method for preparing the polyurethane adhesive according to any one of claims 1 to 12, characterized in that: The preparation method comprises the following steps: (1) mixing the prepolymer A, the prepolymer B and the prepolymer C once to obtain a primary mixture; (2) adding the diluent to the obtained primary mixture for secondary mixing to obtain a secondary mixture; (3) Adding the stabilizer to the obtained secondary mixture and mixing for a third time to obtain a third mixture, i.e., a polyurethane adhesive for road paving.

14. The preparation method according to claim 13, characterized in that: In step (1), the mixing temperature of the primary mixing is 70-90° C., and the mixing time is 0.5-1.5 h.

15. The preparation method according to claim 14, characterized in that: In step (2), the mixing temperature of the secondary mixing is 40-60° C., and the mixing time is 20-40 min.

16. The preparation method according to claim 14, characterized in that: In step (3), the mixing temperature of the three mixings is 20-40° C., and the mixing time is 20-40 min.

17. A polyurethane concrete, characterized in that: The preparation raw materials include polyurethane adhesive and aggregate, and the polyurethane adhesive is the polyurethane adhesive described in any one of claims 1 to 12 and the polyurethane adhesive prepared by the preparation method described in any one of claims 13 to 16.

18. Use of the polyurethane adhesive according to any one of claims 1 to 12 and the polyurethane adhesive prepared by the preparation method according to any one of claims 13 to 16 in the preparation of polyurethane concrete.

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