Inorganic silicon hybrid polyurethane primer as well as preparation method and application thereof

Abstract

The invention provides an inorganic silicon hybrid polyurethane primer as well as a preparation method and application thereof, and belongs to the technical field of primer. The primer provided by the invention is prepared from the following raw materials: polyester polyol, polyether polyol, trimethylolpropane, hexamethylene diisocyanate, 3-(phenylamino) propyltrimethoxysilane, ethyl acetate, xylene, an antioxidant, a light stabilizer, stannous octoate and a catalyst. An isocyanate-terminated polyurethane prepolymer is selected as a base material, a silane hybrid structure is introduced, a Si-O-Si network is formed after silane is hydrolyzed, the Si-O-Si network and Ca < 2 + > in concrete form a coordinate bond, and meanwhile, an isocyanate group reacts with water to generate a urea bond to reinforce anchoring. According to the primer disclosed by the invention, through a chemical-physical synergistic effect, the technical problem of bonding failure of a floating dust hardened layer is systematically solved, and an innovative solution is provided for long-acting sealing of a concrete joint.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of primer, in particular to an inorganic silicon hybrid polyurethane primer, a preparation method and application thereof. BACKGROUND

[0002] In water conservancy projects, the concrete is laid on the whole surface, and the concrete after solidification usually needs to be cut by a professional grinder to deal with the thermal expansion and cold contraction effect in the later construction, and then filled with sealant. In the actual operation process, this mechanical cutting process often causes multiple construction problems. When the cutting blade rotates at high speed and rubs against the concrete, not only a large amount of concrete dust particles with a particle size of 0.1-2 mm is generated, but also these suspended particles will diffuse and deposit under the action of wind, forming a dust layer with a thickness of 0.5-3 mm. More seriously, water washing operation is often used to reduce dust and temperature during construction, and the mud mixed with water and dust will penetrate along the edge of the cutting joint and cause secondary hydration reaction with the surface layer of the concrete which has not completely hardened, finally forming a dense hardened layer on both sides of the joint.

[0003] This composite pollution layer seriously restricts the subsequent sealant construction: first, the dust particles form a physical isolation layer on the surface of the joint, which causes great problems to the adhesion of the sealant; second, the adhesion strength between the hardened layer and the base concrete is insufficient; third, Ca(OH)2 in the hydration product will react with the components in the sealant to form brittle crystals. These factors superimposed cause the adhesion strength of the sealant interface to be greatly reduced, and finally the problem of sealant peeling occurs.

[0004] The primer is widely used in concrete expansion joints, and the traditional primer has the following defects in the application of concrete expansion joints: (1) epoxy resin: too rigid to match the thermal expansion and cold contraction deformation of concrete, brittle cracking below-10℃; easy to fail at low temperature (<5℃); penetration depth is only 0.2-0.5mm, forming a "sandwich" type debonding with the dust layer; (2) acrylic: poor water resistance, easy to saponify with alkaline hydration products in the hardened layer; (3) solvent-based neoprene glue: forms stress concentration points on the surface of the hardened layer, poor alkali resistance; (4) silane coupling agent: only forms a single molecular layer of chemical bond, cannot physically fill the 2-15μm pores; poor compatibility with polyurethane sealant, interface easy to migrate leading to peeling; (5) general primer: lacks targeted design, no passivation effect on Ca(OH)2 adsorbed by dust, long-term contact generates calcium carbonate crystals, accelerating interface peeling.

[0005] Therefore, in order to overcome the technical problem of adhesion failure of concrete expansion joint sealant, it is urgent to develop an inorganic silicon hybrid polyurethane primer which can improve the adhesion strength, weather resistance and penetration depth of concrete. SUMMARY

[0006] The present application aims at providing an inorganic silicon hybrid polyurethane primer, a preparation method and application thereof to overcome the deficiencies of the prior art.

[0007] To achieve the above-mentioned application purposes, the present application provides the following technical solutions.

[0008] The present application provides an inorganic silicon hybrid polyurethane primer, which comprises the following preparation raw materials in mass fraction:

[0009] Polyester polyol 5-10 parts, polyether polyol 10-15 parts, trimethylolpropane 1-3 parts, hexamethylene diisocyanate 6-15 parts, 3-(phenylamino)propyl trimethoxysilane 0.5-2 parts, ethyl acetate 25-30 parts, dimethylbenzene 25-30 parts, antioxidant 0.2-0.5 parts, light stabilizer 0.2-0.5 parts, stannous octoate 0.05-0.2 parts, catalyst 0.1-0.5 parts.

[0010] Preferably, the molecular weight of the polyester polyol is 1900-3000, and the functionality is 2-3; the molecular weight of the polyether polyol is 4800-6500, and the functionality is 3-4.

[0011] Preferably, the antioxidant is antioxidant 1010, the light stabilizer is light stabilizer UV-384, and the catalyst is 2,2'-dimorpholinyl diethyl ether.

[0012] The present application also provides a preparation method of the inorganic silicon hybrid polyurethane primer, comprising the following steps:

[0013] 1) vacuum dewatering polyester polyol and polyether polyol to obtain a mixture;

[0014] 2) mixing the mixture, hexamethylene diisocyanate and stannous octoate and then reacting to obtain a first reaction product;

[0015] 3) mixing the first reaction product and trimethylolpropane and then reacting to obtain a polyurethane prepolymer;

[0016] 4) reacting the polyurethane prepolymer and 3-(phenylamino)propyl trimethoxysilane to obtain a second reaction product;

[0017] 5) mixing the second reaction product, ethyl acetate, dimethylbenzene, antioxidant, light stabilizer and catalyst to obtain the inorganic silicon hybrid polyurethane primer.

[0018] Preferably, the temperature of the vacuum dewatering in step 1) is 110-120 DEG C, the time of the vacuum dewatering is 2.5-3.5 h, and the vacuum degree of the vacuum dewatering is -0.1 to -0.09 MPa.

[0019] As preferred, the mixing in step 2) is that the mixture is cooled to 73-77℃, then hexamethylene diisocyanate and stannous octoate are added, the temperature of the reaction is 75-80℃, and the reaction time is 1.5-2.5h.

[0020] As preferred, the mixing in step 3) is that the first reaction product is cooled to 63-68℃, then trimethylolpropane is slowly added, and the temperature of the reaction system is ≤80℃ during the addition of trimethylolpropane.

[0021] The temperature of the reaction is 75-80℃, and the time is 0.8-1.2h.

[0022] As preferred, in step 4), the polyurethane prepolymer is cooled to ≤50℃, then 3-(phenylamino)propyltrimethoxysilane is added, and the reaction time is 27-33min.

[0023] The mixing in step 5) is that ethyl acetate and dimethylbenzene are first added to the second reaction product for mixing, then antioxidants, light stabilizers and catalysts are added for mixing.

[0024] As preferred, steps 1)-5) are carried out in a protective atmosphere, which is a nitrogen atmosphere or an argon atmosphere.

[0025] The application also provides the use of the inorganic silicon hybrid polyurethane primer in concrete.

[0026] The application has the following beneficial effects:

[0027] 1) The application selects an isocyanate-terminated polyurethane prepolymer as a base material, introduces a silane hybrid structure, and forms a Si-O-Si network after the hydrolysis of silane, which forms a coordination bond with Ca 2+ in concrete, and the isocyanate group reacts with water to form a urea bond to strengthen anchoring. The primer of the application solves the technical problem of bonding failure of the dusted and hardened layer through the synergistic effect of "chemical-physical" action, and provides an innovative solution for long-term sealing of concrete joints.

[0028] 2) The inorganic silicon hybrid polyurethane primer of the application has a simple construction process, high reliability, and is suitable for large-area construction on site. DETAILED DESCRIPTION

[0029] The application provides an inorganic silicon hybrid polyurethane primer, which comprises the following preparation raw materials in mass fractions:

[0030] Polyester polyol 5-10 parts, polyether polyol 10-15 parts, trimethylolpropane 1-3 parts, hexamethylene diisocyanate 6-15 parts, 3-(phenylamino) propyl trimethoxysilane 0.5-2 parts, ethyl acetate 25-30 parts, xylene 25-30 parts, antioxidant 0.2-0.5 parts, light stabilizer 0.2-0.5 parts, stannous octoate 0.05-0.2 parts, catalyst 0.1-0.5 parts.

[0031] In the preparation raw material of the inorganic silicon hybrid polyurethane primer of the application, the mass fraction of the polyester polyol is preferably 6-9 parts, further preferably 7-8 parts; the mass fraction of the polyether polyol is preferably 11-14 parts, further preferably 12-13 parts; the mass fraction of the trimethylolpropane is preferably 1.5-2.5 parts, further preferably 2 parts; the mass fraction of the hexamethylene diisocyanate is preferably 8-13 parts, further preferably 9-12 parts, more preferably 10-11 parts; the mass fraction of the 3-(phenylamino) propyl trimethoxysilane is preferably 0.8-1.6 parts, further preferably 1-1.5 parts, more preferably 1.2-1.3 parts; the mass fraction of the ethyl acetate is preferably 26-29 parts, further preferably 27-28 parts; the mass fraction of the xylene is preferably 26-29 parts, further preferably 27-28 parts; the mass fraction of the antioxidant is preferably 0.3-0.4 parts, further preferably 0.35 parts; the mass fraction of the light stabilizer is preferably 0.3-0.4 parts, further preferably 0.35 parts; the mass fraction of the stannous octoate is preferably 0.08-0.16 parts, further preferably 0.1-0.15 parts, more preferably 0.12-0.13 parts; the mass fraction of the catalyst is preferably 0.2-0.4 parts, further preferably 0.3 parts.

[0032] In the application, the molecular weight of the polyester polyol is preferably 1900-3000, further preferably 1900-2500, more preferably 2000, and the functionality is preferably 2-3, further preferably 2; the molecular weight of the polyether polyol is preferably 4800-6500, further preferably 4800-5500, more preferably 5000, and the functionality is preferably 3-4, further preferably 3.

[0033] In the application, the antioxidant is preferably antioxidant 1010, the light stabilizer is preferably light stabilizer UV-384, and the catalyst is preferably 2,2'-dimorpholinyl diethyl ether.

[0034] The application further provides a preparation method of the inorganic silicon hybrid polyurethane primer, comprising the following steps:

[0035] 1) vacuumizing and dehydrating the polyester polyol and the polyether polyol to obtain a mixture;

[0036] 2) mixing the mixture, hexamethylene diisocyanate and stannous octoate, and then reacting to obtain a first reaction product;

[0037] 3) mixing the first reaction product and trimethylolpropane, and then reacting to obtain a polyurethane prepolymer;

[0038] 4) reacting the polyurethane prepolymer and 3-(phenylamino)propyltrimethoxysilane to obtain a second reaction product;

[0039] 5) mixing the second reaction product, ethyl acetate, dimethylbenzene, an antioxidant, a light stabilizer and a catalyst to obtain an inorganic silicon hybrid polyurethane primer.

[0040] In the present application, the temperature for the vacuum dehydration in step 1) is preferably 110-120℃, further preferably 112-118℃, and more preferably 115-116℃; the time for the vacuum dehydration is preferably 2.5-3.5h, further preferably 3h, and the vacuum degree for the vacuum dehydration is preferably -0.1--0.09MPa, further preferably -0.098--0.092MPa, and more preferably -0.096--0.095MPa.

[0041] In the present application, the mixing in step 2) is preferably mixing the mixture to be cooled to 73-77℃, and then adding hexamethylene diisocyanate and stannous octoate, further preferably to be cooled to 75-76℃, and the temperature for the reaction is preferably 75-80℃, further preferably 76-79℃, and more preferably 77-78℃, and the time for the reaction is preferably 1.5-2.5h, further preferably 1.8-2.2h, and more preferably 2h.

[0042] In the present application, the mixing in step 3) is preferably mixing the first reaction product to be cooled to 63-68℃, and then slowly adding trimethylolpropane, further preferably to be cooled to 65-66℃, and the temperature of the reaction system is preferably ≤80℃ during the process of adding trimethylolpropane;

[0043] The temperature for the reaction is preferably 75-80℃, further preferably 76-79℃, and more preferably 77-78℃, and the time for the reaction is preferably 0.8-1.2h, further preferably 1h.

[0044] In the present application, in step 4), the polyurethane prepolymer is preferably cooled to ≤50℃, and then 3-(phenylamino)propyltrimethoxysilane is added, and the time for the reaction is preferably 27-33min, further preferably 29-31min, and more preferably 30min;

[0045] The mixing in step 5) is preferably mixing the second reaction product by first adding ethyl acetate and dimethylbenzene, and then adding an antioxidant, a light stabilizer and a catalyst.

[0046] In the present application, steps 1) to 5) are preferably carried out under a protective atmosphere, which is preferably a nitrogen atmosphere or an argon atmosphere.

[0047] The present application also provides the use of the inorganic silicon hybrid polyurethane primer in concrete.

[0048] The technical solutions provided by the present application will be described in detail below in conjunction with the examples, but they should not be understood as limiting the scope of protection of the present application.

[0049] In the examples, the molecular weight of the polyester polyol is 2000, and the functionality is 2; the molecular weight of the polyether polyol is 5000, and the functionality is 3; the antioxidant is antioxidant 1010, the light stabilizer is light stabilizer UV-384, and the catalyst is 2,2'-dimorpholinyl diethyl ether.

[0050] Example 1

[0051] The inorganic silicon hybrid polyurethane primer of the present example is prepared from the following raw materials in mass fraction: polyester polyol 8 parts, polyether polyol 12 parts, trimethylolpropane 2 parts, hexamethylene diisocyanate 10 parts, 3-(phenylamino)propyl trimethoxysilane 1.3 parts, ethyl acetate 28 parts, dimethylbenzene 28 parts, antioxidant 0.3 parts, light stabilizer 0.4 parts, stannous octoate 0.12 parts, and catalyst 0.3 parts.

[0052] The reaction of the present example is carried out under nitrogen protection. The polyester polyol and the polyether polyol are mixed and heated to 115°C. Vacuum dehydration is carried out at 115°C and a vacuum degree of -0.096 MPa for 3 hours. The equipment is ensured not to leak. A mixture is obtained. The mixture is cooled to 75°C. Hexamethylene diisocyanate and stannous octoate are added. Reaction is carried out at 78°C for 2 hours. A first reaction product is obtained.

[0053] The first reaction product is cooled to 65°C. Trimethylolpropane is slowly added. The temperature of the reaction system is controlled to be not more than 80°C. After the addition of trimethylolpropane is completed, reaction is carried out at 78°C for 1 hour. A polyurethane prepolymer is obtained.

[0054] The polyurethane prepolymer is cooled to 48°C. 3-(phenylamino)propyl trimethoxysilane is added. Reaction is carried out at 48°C for 30 minutes. Then ethyl acetate and dimethylbenzene are added. After stirring uniformly, antioxidant, light stabilizer, and catalyst are added. After stirring uniformly, an inorganic silicon hybrid polyurethane primer is obtained.

[0055] Example 2

[0056] The inorganic silicon hybrid polyurethane primer of the present example is prepared from the following raw materials in mass fraction: polyester polyol 6 parts, polyether polyol 10 parts, trimethylolpropane 1 part, hexamethylene diisocyanate 8 parts, 3-(phenylamino)propyl trimethoxysilane 1.6 parts, ethyl acetate 30 parts, dimethylbenzene 30 parts, antioxidant 0.2 parts, light stabilizer 0.4 parts, stannous octoate 0.08 parts, catalyst 0.2 parts.

[0057] The reaction of the present example is carried out under nitrogen protection. The polyester polyol and the polyether polyol are mixed and heated to 110°C. Vacuum dehydration is carried out at 110°C and -0.092 MPa vacuum degree for 3.5 hours. The equipment is ensured not to leak. The mixture is obtained. The mixture is cooled to 73°C. Hexamethylene diisocyanate and stannous octoate are added. The reaction is carried out at 76°C for 2.2 hours. The first reaction product is obtained.

[0058] The first reaction product is cooled to 63°C. Trimethylolpropane is slowly added. The temperature of the reaction system is controlled to be not more than 80°C. After the trimethylolpropane is completely added, the reaction is carried out at 75°C for 1.2 hours. The polyurethane prepolymer is obtained.

[0059] The polyurethane prepolymer is cooled to 45°C. 3-(phenylamino)propyl trimethoxysilane is added. The reaction is carried out at 45°C for 33 minutes. Then ethyl acetate and dimethylbenzene are added and stirred uniformly. The antioxidant, the light stabilizer and the catalyst are added and stirred uniformly. The inorganic silicon hybrid polyurethane primer is obtained.

[0060] Example 3

[0061] The inorganic silicon hybrid polyurethane primer of the present example is prepared from the following raw materials in mass fraction: polyester polyol 6 parts, polyether polyol 10 parts, trimethylolpropane 1 part, hexamethylene diisocyanate 8 parts, 3-(phenylamino)propyl trimethoxysilane 1.6 parts, ethyl acetate 30 parts, dimethylbenzene 30 parts, antioxidant 0.2 parts, light stabilizer 0.4 parts, stannous octoate 0.08 parts, catalyst 0.2 parts.

[0062] The reaction of the present example is carried out under nitrogen protection. The polyester polyol and the polyether polyol are mixed and heated to 110°C. Vacuum dehydration is carried out at 110°C and -0.092 MPa vacuum degree for 3.5 hours. The equipment is ensured not to leak. The mixture is obtained. The mixture is cooled to 73°C. Hexamethylene diisocyanate and stannous octoate are added. The reaction is carried out at 76°C for 2.2 hours. The first reaction product is obtained.

[0063] The first reaction product is cooled to 63°C. Trimethylolpropane is slowly added. The temperature of the reaction system is controlled to be not more than 80°C. After the trimethylolpropane is completely added, the reaction is carried out at 75°C for 1.2 hours. The polyurethane prepolymer is obtained.

[0064] The polyurethane prepolymer is cooled to 47℃, 3-(phenylamino)propyl trimethoxysilane is added, and the reaction is carried out at 47℃ for 27 min. Then, ethyl acetate, xylene are added, and stirred uniformly. Then, antioxidants, light stabilizers, and catalysts are added, and stirred uniformly. The whole reaction process is carried out under nitrogen protection. An inorganic silicon hybrid polyurethane primer is obtained.

[0065] The glass transition temperature of the inorganic silicon hybrid polyurethane primer of examples 1-3 is extended to -40℃ by DSC test.

[0066] The inorganic silicon hybrid polyurethane primer of examples 1-3 is used for construction and glueing. The specific process steps are as follows: (1) base surface treatment: air blower blows off floating dust, steel brush polishes the hardened layer to expose C40 concrete aggregate, and high-pressure water gun washes off floating dust at a pressure of 0.7 MPa; (2) primer construction: the inorganic silicon hybrid polyurethane primer of examples 1-3 is added into mixed solvent (consisting of xylene, ethyl acetate and butyl acetate at a volume ratio of 10:5:5) to obtain a primer solution with a solid content of 50%, a viscosity of 65 mPa·s and a surface tension of 34 mN / m. The primer solution of examples 1-3 is brushed with a brush, and the brushing thickness is 0.2 mm. Curing is carried out at 25℃ and 50% humidity for 45 min; (3) pouring sealant: after the primer is cured, polyurethane sealant is poured, and high-pressure glue gun is used for construction, and the glue outlet is cut at an angle of 45° into the joint for glueing construction; (4) leveling and curing: the glue surface is leveled with a spatula at an angle of 45°, the glue surface concave joint is kept at 4 mm, no load is allowed within 24 h, and the bonding effect is detected after the glue is completely cured after 48 h.

[0067] In the standard test specimen (C40 concrete), the bonding strength of the primer of examples 1-3 reaches 1.6 MPa, 1.55 MPa and 1.5 MPa respectively, and the failure interface occurs in the concrete matrix rather than the bonding layer, indicating that the interfacial bonding strength has exceeded the sealant itself. The inorganic silicon hybrid polyurethane primer is significantly better than the traditional primer material in terms of concrete bonding performance.

[0068] According to JC / T 482-2022 "Polyurethane Building Sealant", the weather resistance test results show that after temperature variation cycle of -40-60℃, the bonding strength retention rates of the inorganic silicon hybrid polyurethane primer of examples 1-3 are 88%, 86% and 87% respectively, and there is no delamination and falling off after boiling in water for 48 h.

[0069] According to the capillary tube test verification, the penetration speed of the primer of examples 1-3 in the concrete pores reaches 2.2 mm / s, 2.1 mm / s and 2 mm / s respectively, and an enhanced layer with a depth of >2 mm is formed after 48 h, and the siloxane network of the primer is combined with Ca 2+The isocyanate group forms a polyurea structure which effectively fills the micropores and ensures the formation of a continuous film layer on the surface of the compacted layer.

[0070] The above description is only the preferred embodiment of the present application, it should be pointed out that for the ordinary skilled in the art, without departing from the principles of the present application, can also make a number of improvements and refinements, these improvements and refinements should also be considered as the protection scope of the present application.

Claims

1. An inorganic silicon hybrid polyurethane primer, characterized in that, The preparation raw materials comprise the following parts by weight: The composition includes 5-10 parts polyester polyol, 10-15 parts polyether polyol, 1-3 parts trimethylolpropane, 6-15 parts hexamethylene diisocyanate, 0.5-2 parts 3-(phenylamino)propyltrimethoxysilane, 25-30 parts ethyl acetate, 25-30 parts xylene, 0.2-0.5 parts antioxidant, 0.2-0.5 parts light stabilizer, 0.05-0.2 parts stannous octoate, and 0.1-0.5 parts catalyst.

2. The inorganic silicon hybrid polyurethane primer according to claim 1, characterized in that, The polyester polyol has a molecular weight of 1900-3000 and a functionality of 2-3; the polyether polyol has a molecular weight of 4800-6500 and a functionality of 3-4.

3. The inorganic silicon hybrid polyurethane primer according to claim 1 or 2, characterized in that, The antioxidant is antioxidant 1010, the light stabilizer is light stabilizer UV-384, and the catalyst is 2,2'-dimorpholinodiethyl ether.

4. The method for preparing the inorganic silicon hybrid polyurethane primer according to any one of claims 1 to 3, characterized in that, It includes the following steps: 1) The polyester polyol and polyether polyol were dehydrated under vacuum to obtain a mixture; 2) The mixture, hexamethylene diisocyanate and stannous octoate were mixed and reacted to obtain the first reaction product; 3) The first reaction product is mixed with trimethylolpropane and then reacted to obtain a polyurethane prepolymer; 4) The polyurethane prepolymer and 3-(phenylamino)propyltrimethoxysilane react to obtain the second reaction product; 5) The second reaction product, ethyl acetate, xylene, antioxidant, light stabilizer and catalyst are mixed to obtain an inorganic silicon hybrid polyurethane primer.

5. The preparation method according to claim 4, characterized in that, The vacuum dehydration temperature in step 1) is 110-120℃, the vacuum dehydration time is 2.5-3.5h, and the vacuum degree of vacuum dehydration is -0.1 to -0.09MPa.

6. The preparation method according to claim 4 or 5, characterized in that, Step 2) The mixing process involves cooling the mixture to 73-77°C and then adding hexamethylene diisocyanate and stannous octoate. The reaction temperature is 75-80°C and the reaction time is 1.5-2.5 hours.

7. The preparation method according to claim 6, characterized in that, Step 3) The first reaction product is cooled to 63-68°C and then trimethylolpropane is slowly added. During the addition of trimethylolpropane, the temperature of the reaction system is ≤80°C. The reaction is carried out at a temperature of 75–80°C for a time of 0.8–1.2 h.

8. The preparation method according to claim 7, characterized in that, In step 4), the polyurethane prepolymer is cooled to ≤50℃, and 3-(phenylamino)propyltrimethoxysilane is added. The reaction time is 27-33 min. Step 5) The mixing process involves first adding ethyl acetate and xylene to the second reaction product and mixing them, then adding antioxidants, light stabilizers, and catalysts and mixing them.

9. The preparation method according to claim 7 or 8, characterized in that, Steps 1) through 5) are carried out under a protective atmosphere, which is either nitrogen or argon.

10. The application of the inorganic silicon hybrid polyurethane primer according to any one of claims 1 to 3 in concrete.