Modified epoxy resin and preparation method thereof, composition for epoxy resin grouting material, epoxy resin grouting material and preparation method and application of epoxy resin grouting material

Abstract

The invention relates to the technical field of concrete materials, and discloses modified epoxy resin and a preparation method thereof, a composition for an epoxy resin grouting material, the epoxy resin grouting material and a preparation method and application of the epoxy resin grouting material. The method for preparing the modified epoxy resin comprises the following steps: heating a polyhydroxy compound and epoxy resin at 80-100 DEG C in a nitrogen atmosphere in the presence of a catalyst to obtain the modified epoxy resin, the molar ratio of the polyhydroxy compound to the epoxy resin to the catalyst is 1: (1-2): (0.05-0.1); the epoxy resin is bisphenol A epoxy resin; the catalyst is selected from any one of sodium hydroxide, potassium carbonate and dimethylaniline; the multi-hydroxyl compound is selected from at least one of glycerol, ethylene glycol, propylene glycol, glucose and butanediol. The epoxy resin grouting material provided by the invention has more excellent toughness and lower viscosity, and has good bonding strength and bonding durability with a concrete matrix.

Description

Technical Field

[0001] The invention relates to the technical field of concrete materials, and in particular to a modified epoxy resin and a preparation method thereof, a composition for an epoxy resin grouting material, an epoxy resin grouting material and a preparation method and application thereof. Background Art

[0002] Concrete plays an irreplaceable and important role in infrastructure construction, providing a reliable foundation for human habitation, production and development. However, concrete structures are inevitably prone to cracks and other defects when they are subjected to coupled loads such as rain, temperature and vibration for a long time. Moisture in the air carrying corrosive substances will more easily enter the concrete structure through this channel, causing steel bar corrosion and seriously affecting the safety of the concrete structure.

[0003] The current specifications have strict requirements for the repair of concrete structure cracks. For example, in the railway industry, Q / CR 802-2020 stipulates that cracks larger than 0.2 mm and cracks smaller than 0.5 mm in ballastless track will be repaired with resin. It can be seen that the repair of concrete structure cracks is usually repaired with organic adhesives such as epoxy resin.

[0004] Although the existing epoxy resin has overcome the disadvantages of high viscosity and low elongation at break during modification, the bonding compatibility between epoxy resin and concrete materials and the bonding durability of epoxy resin have not been overcome. Therefore, when repairing cracks, the use of existing grouting materials can easily lead to repair failure.

[0005] Studies have shown that the bonding source between epoxy resin and concrete matrix is ​​essentially the result of mechanical bite and chemical bonding (mainly secondary bonds such as hydrogen bonds). The ability of epoxy resin to penetrate concrete directly determines the above two effects, and the polarity of epoxy resin is the basis for ensuring the ability to penetrate cement-based materials. At the same time, in order to adapt the compatibility of the epoxy resin grouting material and the concrete bonding interface, the introduction of inorganic micro-nano materials can enhance the interface compatibility while enhancing the toughness of epoxy resin cured products.

[0006] CN108676535A discloses a low-viscosity tough tall oil-based epoxy crack repair material and a preparation method and application thereof, comprising bisphenol A epoxy resin (E51), a toughening agent oil-based polyurethane prepolymer, an active diluent, a curing agent, a modifier, a promoter and an auxiliary agent; however, this scheme has problems such as poor bonding compatibility and poor bonding durability between the epoxy crack repair material and cement-based materials.

[0007] In summary, there is an urgent need to develop a low-polarity epoxy resin grouting material suitable for long-lasting concrete bonding and a preparation method thereof. Summary of the invention

[0008] The purpose of the invention is to overcome the problems of low bonding strength and poor bonding durability between epoxy resin grouting materials and concrete substrates in the prior art.

[0009] In order to achieve the above object, the first aspect of the present invention provides a method for preparing a modified epoxy resin, the method comprising: in a protective atmosphere, in the presence of a catalyst, heating a polyhydroxy compound and an epoxy resin at 80-100° C. to obtain a modified epoxy resin;

[0010] The molar ratio of the polyhydroxy compound, the epoxy resin and the catalyst is 1:1-2:0.05-0.1; the epoxy resin is a bisphenol A epoxy resin; the catalyst is selected from any one of sodium hydroxide, potassium carbonate and dimethylaniline; the polyhydroxy compound is selected from at least one of glycerol, ethylene glycol, propylene glycol, glucose and butanediol.

[0011] The second aspect of the present invention provides a modified epoxy resin prepared by the method described in the first aspect.

[0012] A third aspect of the present invention provides a composition for an epoxy resin grouting material, wherein the composition comprises, for every 100 parts by weight of the modified epoxy resin, 20-30 parts by weight of the first diluent, 1-3 parts by weight of the second diluent, 20-40 parts by weight of the first amine curing agent, 5-10 parts by weight of the second amine curing agent, 0.1-0.2 parts by weight of the defoaming agent, and 50-100 parts by weight of the filler;

[0013] The first amine curing agent is a modified phenolic amine, and the amine value of the modified phenolic amine is 200-500KOH / g, and the viscosity at 25°C is 1-2Pa·s; the second amine curing agent is a hyperbranched polyamide with an intrinsic viscosity of 0.05-0.3g / dL; the first diluent is selected from at least one of polypropylene glycol diglycidyl ether, polyethylene oxide diglycidyl ether, 1,4-butanediol diglycidyl ether and 1,6-hexanediol diglycidyl ether; the second diluent is selected from at least one of ethanol, acetone and isopropanol;

[0014] The modified epoxy resin is the modified epoxy resin described in the second aspect.

[0015] A fourth aspect of the present invention provides a method for preparing an epoxy resin grouting material, the method comprising:

[0016] (1) performing a first mixing process on a first diluent, a second diluent and a modified epoxy resin to obtain a mixture I;

[0017] (2) subjecting the mixture I, the defoamer and the filler to a second mixing process to obtain a mixture II;

[0018] (3) performing a third mixing process on the mixture II, the first amine curing agent and the second amine curing agent to obtain an epoxy resin grouting material;

[0019] Relative to every 100 parts by weight of the modified epoxy resin, the content of the first diluent is 20-30 parts by weight, the content of the second diluent is 1-3 parts by weight, the content of the first amine curing agent is 20-40 parts by weight, the content of the second amine curing agent is 5-10 parts by weight, the content of the defoaming agent is 0.1-0.2 parts by weight, and the content of the filler is 50-100 parts by weight;

[0020] The first amine curing agent is a modified phenolic amine, and the amine value of the modified phenolic amine is 200-500KOH / g, and the viscosity at 25°C is 1-2Pa·s; the second amine curing agent is a hyperbranched polyamide with an intrinsic viscosity of 0.05-0.3g / dL; the first diluent is selected from at least one of polypropylene glycol diglycidyl ether, polyethylene oxide diglycidyl ether, 1,4-butanediol diglycidyl ether and 1,6-hexanediol diglycidyl ether; the second diluent is selected from at least one of ethanol, acetone and isopropanol;

[0021] The modified epoxy resin is the modified epoxy resin described in the second aspect.

[0022] The fifth aspect of the present invention provides an epoxy resin grouting material prepared by the method described in the fourth aspect.

[0023] The sixth aspect of the present invention provides the use of the epoxy resin grouting material described in the fifth aspect in concrete.

[0024] The present invention has at least the following advantages:

[0025] (1) The epoxy resin grouting material of the present invention has low polarity and can better infiltrate the concrete matrix. Under the mechanical bite action and chemical bonding action, the bonding strength with the concrete matrix is ​​further enhanced.

[0026] (2) The epoxy resin grouting material of the present invention has good toughness and low viscosity.

[0027] (3) The epoxy resin grouting material of the present invention can effectively increase the wetting performance of the epoxy resin grouting material on the water-covered concrete matrix by changing the surface structure of the water-covering layer at the concrete crack interface, thereby effectively solving the problem of poor affinity between the epoxy resin grouting material and water.

[0028] (4) The epoxy resin grouting material of the present invention has the advantage of good bonding durability. DETAILED DESCRIPTION

[0029] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0030] The solid-liquid mass ratio in the present invention refers to the mass ratio of solid to liquid.

[0031] As mentioned above, the first aspect of the present invention provides a method for preparing a modified epoxy resin, the method comprising: in a protective atmosphere, in the presence of a catalyst, heating a polyhydroxy compound and an epoxy resin at 80-100° C. to obtain a modified epoxy resin;

[0032] The molar ratio of the polyhydroxy compound, the epoxy resin and the catalyst is 1:1-2:0.05-0.1; the epoxy resin is a bisphenol A epoxy resin; the catalyst is selected from any one of sodium hydroxide, potassium carbonate and dimethylaniline; the polyhydroxy compound is selected from at least one of glycerol, ethylene glycol, propylene glycol, glucose and butanediol.

[0033] Preferably, the bisphenol A epoxy resin is E51 epoxy resin and / or E44 epoxy resin. The inventors of the present invention have found that under this preferred condition, the epoxy resin grouting material of the present invention has better toughness and lower viscosity, and has good bonding strength and bonding durability with the concrete matrix.

[0034] Preferably, the conditions for the heating treatment include: a time of 6-12 hours and a stirring speed of 500-1000 rpm.

[0035] As mentioned above, the second aspect of the present invention provides a modified epoxy resin prepared by the method described in the first aspect.

[0036] Preferably, the epoxy value of the modified epoxy resin is 0.2-0.3. The inventors of the present invention have found that under this preferred condition, the epoxy resin grouting material of the present invention has better toughness and lower viscosity, and has good bonding strength and bonding durability with the concrete matrix.

[0037] Preferably, the protective atmosphere is nitrogen.

[0038] As mentioned above, the third aspect of the present invention provides a composition for epoxy resin grouting material, in which, for every 100 parts by weight of modified epoxy resin, the content of the first diluent is 20-30 parts by weight, the content of the second diluent is 1-3 parts by weight, the content of the first amine curing agent is 20-40 parts by weight, the content of the second amine curing agent is 5-10 parts by weight, the content of the defoaming agent is 0.1-0.2 parts by weight, and the content of the filler is 50-100 parts by weight;

[0039] The first amine curing agent is a modified phenolic amine, and the amine value of the modified phenolic amine is 200-500KOH / g, and the viscosity at 25°C is 1-2Pa·s; the second amine curing agent is a hyperbranched polyamide with an intrinsic viscosity of 0.05-0.3g / dL; the first diluent is selected from at least one of polypropylene glycol diglycidyl ether, polyethylene oxide diglycidyl ether, 1,4-butanediol diglycidyl ether and 1,6-hexanediol diglycidyl ether; the second diluent is selected from at least one of ethanol, acetone and isopropanol;

[0040] The modified epoxy resin is the modified epoxy resin described in the second aspect.

[0041] According to a particularly preferred embodiment, the hyperbranched polyamide is prepared by the following method, which comprises:

[0042] (1) mixing a sodium hydroxide solution and aminoacetic acid to obtain a solution I; performing a first reaction on the solution I and 3,5-dinitrobenzoyl chloride, and dropping the sodium hydroxide solution during the first reaction, maintaining the reaction pH at 8-9 during the first reaction, to obtain a substance I; the conditions of the first reaction include: a reaction time of 15-25 min;

[0043] (2) acidifying the substance I with dilute hydrochloric acid to obtain substance II; and recrystallizing the substance II to obtain substance III;

[0044] (3) subjecting the substance III to a self-condensation reaction to obtain the hyperbranched polyamide; the conditions of the self-condensation reaction include: under a nitrogen atmosphere, a temperature of 150-160° C., and a time of 4-5 hours.

[0045] The inventors of the present invention have found that under this preferred condition, the epoxy resin grouting material of the present invention has better toughness and lower viscosity, and has good bonding strength and bonding durability with the concrete matrix.

[0046] Preferably, the intrinsic viscosity of the hyperbranched polyamide is 0.2-0.25 g / dL, and the molecular weight is 3-4 kg / mol. The inventors of the present invention have found that under this preferred condition, the epoxy resin grouting material of the present invention has better toughness and lower viscosity, and has good bonding strength and bonding durability with the concrete matrix.

[0047] Preferably, the defoamer is a polyether defoamer.

[0048] Preferably, the average particle diameter of the filler is less than 50 μm.

[0049] Further preferably, the filler is selected from at least one of cement, limestone powder, amorphous calcium silicate hydrate, quartz powder, slag, ceramic powder, fly ash, silica fume, white carbon black and talc.

[0050] In a preferred case, the filler is selected from amorphous calcium silicate hydrate. The inventors of the present invention have found that under this preferred condition, the epoxy resin grouting material of the present invention has better toughness.

[0051] According to a particularly preferred embodiment, the amorphous calcium silicate hydrate is prepared by the following method, which comprises: hydrothermal reaction of calcium oxide and nano-silicon dioxide, wherein the mass ratio of calcium oxide to nano-silicon dioxide is 1:0.8-1.2, and the solid-liquid mass ratio is 1:8-12 at the beginning of the reaction; the conditions of the hydrothermal reaction include: temperature of 75-85°C and time of 7-9h. The inventors of the present invention have found that under this preferred condition, the epoxy resin grouting material of the present invention has better toughness and lower viscosity, and has good bonding strength and bonding durability with the concrete matrix.

[0052] It should be noted that the first amine curing agent in the present invention also includes: ethylenediamine, diethylenetriamine, triethylenetetramine, triethanolamine, tetraethylenepentamine, dipropylenetriamine and triethylenediamine, but the inventors of the present invention found that when the first amine curing agent is a modified phenolic amine, combined with the remaining components in the present invention, the prepared epoxy resin grouting material has better toughness and lower viscosity, and has good bonding strength and bonding durability with the concrete matrix.

[0053] As mentioned above, the fourth aspect of the present invention provides a method for preparing an epoxy resin grouting material, the method comprising:

[0054] (1) performing a first mixing process on a first diluent, a second diluent and a modified epoxy resin to obtain a mixture I;

[0055] (2) subjecting the mixture I, the defoamer and the filler to a second mixing process to obtain a mixture II;

[0056] (3) performing a third mixing process on the mixture II, the first amine curing agent and the second amine curing agent to obtain an epoxy resin grouting material;

[0057] For every 100 parts by weight of the modified epoxy resin, the first diluent is used in an amount of 20-30 parts by weight, the second diluent is used in an amount of 1-3 parts by weight, the first amine curing agent is used in an amount of 20-40 parts by weight, the second amine curing agent is used in an amount of 5-10 parts by weight, the defoaming agent is used in an amount of 0.1-0.2 parts by weight, and the filler is used in an amount of 50-100 parts by weight;

[0058] The first amine curing agent is a modified phenolic amine, and the amine value of the modified phenolic amine is 200-500KOH / g, and the viscosity at 25°C is 1-2Pa·s; the second amine curing agent is a hyperbranched polyamide with an intrinsic viscosity of 0.05-0.3g / dL; the first diluent is selected from at least one of polypropylene glycol diglycidyl ether, polyethylene oxide diglycidyl ether, 1,4-butanediol diglycidyl ether and 1,6-hexanediol diglycidyl ether; the second diluent is selected from at least one of ethanol, acetone and isopropanol;

[0059] The modified epoxy resin is the modified epoxy resin described in the second aspect.

[0060] The present invention has no particular limitation on the methods of the first mixing, the second mixing and the third mixing, and those skilled in the art may select them according to conventional methods, which should not be construed as limiting the present invention. Exemplarily, the conditions of the first mixing include: a stirring speed of 100-200 rpm and a time of 1-2 min; the conditions of the second mixing include: a stirring speed of 50-100 rpm and a time of 1-2 min; the conditions of the third mixing include: a stirring speed of 100-200 rpm and a time of 1-2 min.

[0061] As mentioned above, the fifth aspect of the present invention provides an epoxy resin grouting material prepared by the method described in the fourth aspect.

[0062] As mentioned above, the sixth aspect of the present invention provides the use of the epoxy resin grouting material described in the fifth aspect in concrete.

[0063] The present invention will be described in detail below by way of examples. In the following examples, unless otherwise specified, the instruments, reagents, materials, etc. involved are conventional instruments, reagents, materials, etc., which can be obtained through regular commercial channels.

[0064] DGEBA epoxy resin: model Phoenix brand E51, purchased from Shandong Yousuo Chemical Technology Co., Ltd.

[0065] Modified phenolic amine: amine value is 300KOH / g, viscosity is 1.2Pa·s at 25°C, model T31, purchased from Changzhou Runxiang Chemical Co., Ltd.

[0066] Polyether defoamer: Model ZJ-D130, purchased from Jiangsu Zhaojia Building Materials Technology Co., Ltd.

[0067] The average particle diameter of the filler is 15 μm.

[0068] In the present invention, 1 part by weight means 10 g.

[0069] The molecular weight of the hyperbranched polyamide in the present invention is tested by gel permeation chromatography, wherein the mobile phase is chromatography grade THF (tetrahydrofuran).

[0070] The intrinsic viscosity of the hyperbranched polyamide in the present invention refers to the ratio of the specific viscosity at the limiting concentration in a dilute solution to the solution concentration, and is tested according to GB / T 1632 standard.

[0071] Fly ash: specific surface area 427m 2 / kg, loss on ignition 1.7wt%, purchased from Changde Power Generation Co., Ltd.

[0072] Preparation 1 to Preparation Example 3 are used to prepare modified epoxy resin:

[0073] Preparation Example 1

[0074] In a nitrogen atmosphere, glycerol (polyhydroxy compound, specifically 1 mol), DGEBA epoxy resin (epoxy resin) and dimethylaniline (catalyst) in a molar ratio of 1:1:0.05 were heated at 100°C and a stirring speed of 500 rpm for 6 h to obtain a modified epoxy resin with an epoxide value of 0.29, named G1.

[0075] Preparation Example 2

[0076] In a nitrogen atmosphere, 1 mol of glycerol (polyhydroxy compound, specifically 1 mol), DGEBA epoxy resin (epoxy resin) and dimethylaniline (catalyst) in a molar ratio of 1:1:0.05 were heated at 150°C and a stirring speed of 500 rpm for 6 h to obtain a modified epoxy resin with an epoxide value of 0.22, named G2.

[0077] Preparation Example 3

[0078] In a nitrogen atmosphere, 1 mol of glycerol (polyhydroxy compound, specifically 1 mol), DGEBA epoxy resin (epoxy resin) and dimethylaniline (catalyst) in a molar ratio of 1:3:0.01 were heated at 100°C and a stirring speed of 500 rpm for 6 h to obtain a modified epoxy resin with an epoxide value of 0.36, named G3.

[0079] Preparation Examples 4 to 6 are used to prepare hyperbranched polyamide:

[0080] Preparation Example 4

[0081] (1) 20 mL of 1 g / mol sodium hydroxide solution and 3.0 g of aminoacetic acid are mixed to obtain solution I; the solution I and 9.2 g of 3,5-dinitrobenzoyl chloride are subjected to a first reaction, and the sodium hydroxide solution is added dropwise during the first reaction to maintain the reaction pH at 8.5 throughout the first reaction to obtain substance I; the conditions of the first reaction include: a time of 20 min;

[0082] (2) treating the substance I with dilute hydrochloric acid to obtain substance II; and recrystallizing the substance II to obtain substance III; the acidification time is 10 min;

[0083] (3) subjecting the substance III to a self-condensation reaction to obtain the hyperbranched polyamide; the conditions of the self-condensation reaction include: under a nitrogen atmosphere, a temperature of 160° C., and a time of 4 hours;

[0084] The hyperbranched polyamide is named as hyperbranched polyamide I, as shown in Table 1.

[0085] Preparation Example 5

[0086] (1) 20 mL of 1 g / mol sodium hydroxide solution and 3.0 g of aminoacetic acid are mixed to obtain solution I; the solution I and 9.2 g of 3,5-dinitrobenzoyl chloride are subjected to a first reaction, and the sodium hydroxide solution is added dropwise during the first reaction to maintain the reaction pH at 8.5 throughout the first reaction to obtain substance I; the conditions of the first reaction include: a time of 20 min, and controlling the pH of the first reaction to be 8.5;

[0087] (2) treating the substance I with dilute hydrochloric acid to obtain substance II; and recrystallizing the substance II to obtain substance III; the acidification time is 10 min;

[0088] (3) subjecting the substance III to a self-condensation reaction to obtain the hyperbranched polyamide; the conditions of the self-condensation reaction include: under a nitrogen atmosphere, a temperature of 160° C., and a time of 5 hours;

[0089] The hyperbranched polyamide is named as hyperbranched polyamide II, as shown in Table 1.

[0090] Preparation Example 6

[0091] (1) 20 mL of 1 g / mol sodium hydroxide solution and 3.0 g of aminoacetic acid are mixed to obtain solution I; the solution I and 9.2 g of 3,5-dinitrobenzoyl chloride are subjected to a first reaction, and the sodium hydroxide solution is added dropwise during the first reaction to maintain the reaction pH at 8.5 throughout the first reaction to obtain substance I; the conditions of the first reaction include: a time of 20 min, and controlling the pH of the first reaction to be 8.5;

[0092] (2) treating the substance I with dilute hydrochloric acid to obtain substance II; and recrystallizing the substance II to obtain substance III; the acidification time is 10 min;

[0093] (3) subjecting the substance III to a self-condensation reaction to obtain the hyperbranched polyamide; the conditions of the self-condensation reaction include: under a nitrogen atmosphere, a temperature of 160° C., and a time of 6 hours;

[0094] The hyperbranched polyamide is named as hyperbranched polyamide III, as shown in Table 1.

[0095] Table 1

[0096] Molecular weight / (kg / mol) Intrinsic viscosity / g / dL Hyperbranched polyamide I 3.21 0.23 Hyperbranched polyamide II 0.69 0.27 Hyperbranched polyamide III 10.7 0.51

[0097] Preparation Example 7 is used to prepare amorphous calcium silicate hydrate:

[0098] Preparation Example 7

[0099] Calcium oxide and nano-silicon dioxide in a mass ratio of 1:1 are hydrothermally reacted with water to ensure that the solid-liquid mass ratio at the beginning of the hydrothermal reaction is 1:10; the conditions of the hydrothermal reaction include: temperature of 80° C. and time of 8 hours; and amorphous hydrated calcium silicate is obtained.

[0100] Example 1

[0101] (1) performing a first mixing treatment on 1,4-butanediol diglycidyl ether (a first diluent), acetone (a second diluent) and G1 (a modified epoxy resin) at a stirring speed of 200 rpm for 2 minutes to obtain a mixture I;

[0102] (2) subjecting the mixture I, the polyether defoamer (defoamer) and the amorphous calcium silicate hydrate (filler) to a second mixing treatment at a stirring speed of 100 rpm for 2 min to obtain a mixture II;

[0103] (3) The mixture II, the modified phenolic amine (the first amine curing agent) and the hyperbranched polyamide (the second amine curing agent) were subjected to a third mixing treatment at a stirring speed of 200 rpm for 2 minutes to obtain an epoxy resin grouting material, which was named Z1.

[0104] Example 2

[0105] This embodiment adopts a similar process flow to that of Embodiment 1, except that the amount of G1 is different. The rest is the same as that of Embodiment 1, and an epoxy resin grouting material is prepared, named Z2. See Table 2 for details.

[0106] Example 3

[0107] This embodiment adopts a similar process flow to that of Embodiment 1, except that the amount of 1,4-butanediol diglycidyl ether is different. The rest is the same as that of Embodiment 1, and an epoxy resin grouting material is prepared, named Z3. See Table 2 for details.

[0108] Example 4

[0109] This embodiment adopts a similar process flow to that of Embodiment 1, except that the amount of acetone used is different. The rest is the same as that of Embodiment 1, and an epoxy resin grouting material is prepared, named Z4, as shown in Table 2 for details.

[0110] Example 5

[0111] This embodiment adopts a similar process flow to that of Embodiment 1, except that the amount of filler used is different. The rest is the same as that of Embodiment 1, and an epoxy resin grouting material is prepared, named Z5, as shown in Table 2 for details.

[0112] Example 6

[0113] This embodiment adopts a similar process flow to that of Embodiment 1, except that the amount of modified phenolic amine used is different. The rest is the same as that of Embodiment 1, and an epoxy resin grouting material is prepared, named Z6. See Table 2 for details.

[0114] Example 7

[0115] This embodiment adopts a similar process flow to that of Embodiment 1, except that the amount of hyperbranched polyamide used is different. The rest is the same as that of Embodiment 1, and an epoxy resin grouting material is prepared, named Z7, as shown in Table 2 for details.

[0116] Example 8

[0117] This embodiment adopts a similar process flow to that of Embodiment 1, except that the type of hyperbranched polyamide is different. The rest is the same as that of Embodiment 1, and an epoxy resin grouting material is prepared, named Z8. See Table 2 for details.

[0118] Example 9

[0119] This embodiment adopts a similar process flow to that of Embodiment 1, except that amorphous calcium silicate hydrate is replaced with fly ash of equal weight and particle size, and the rest is the same as that of Embodiment 1 to prepare an epoxy resin grouting material named Z9. See Table 2 for details.

[0120] Comparative Example 1

[0121] This comparative example adopts a similar process flow to Example 1, except that G1 is replaced by an equal weight amount of DGEBA epoxy resin, and the rest is the same as Example 1 to prepare an epoxy resin grouting material, named DZ1, see Table 3 for details.

[0122] Comparative Example 2

[0123] This comparative example adopts a similar process flow to Example 1, except that 1,4-butanediol diglycidyl ether (the first diluent) is not added. The rest is the same as Example 1 to prepare an epoxy resin grouting material, named DZ2, see Table 3 for details.

[0124] Comparative Example 3

[0125] This comparative example adopts a similar process flow to Example 1, except that acetone (the second diluent) is not added. The rest is the same as Example 1 to prepare an epoxy resin grouting material, named DZ3, see Table 3 for details.

[0126] Comparative Example 4

[0127] This comparative example adopts a similar process flow to Example 1, except that amorphous calcium silicate hydrate (filler) is not added. The rest is the same as Example 1 to prepare an epoxy resin grouting material named DZ4. See Table 3 for details.

[0128] Comparative Example 5

[0129] This comparative example adopts a similar process flow to Example 1, except that the type of the second amine curing agent is different. The rest is the same as Example 1, and an epoxy resin grouting material is prepared, named DZ5, see Table 3 for details.

[0130] Comparative Example 6

[0131] This comparative example adopts a similar process flow to Example 1, except that G1 is replaced by G2 in equal weight, and the rest is the same as Example 1 to prepare an epoxy resin grouting material named DZ6. See Table 3 for details.

[0132] Comparative Example 7

[0133] This comparative example adopts a similar process flow to Example 1, except that G1 is replaced by G3 in equal weight, and the rest is the same as Example 1 to prepare an epoxy resin grouting material named DZ7. See Table 3 for details.

[0134] Comparative Example 8

[0135] This comparative example adopts a similar process flow to Example 1, except that the amount of each component is different. The rest is the same as Example 1, and an epoxy resin grouting material is prepared, named DZ8, see Table 3 for details.

[0136] Table 2

[0137]

[0138]

[0139] Table 2

[0140]

[0141] Table 3

[0142]

[0143]

[0144] Table 3

[0145] Comparative Example 6 Comparative Example 7 Comparative Example 8 Types of modified epoxy resins G2 G3 Same as Example 1 Amount of modified epoxy resin / part by weight Same as Example 1 Same as Example 1 120 Amount / weight of 1,4-butanediol diglycidyl ether Same as Example 1 Same as Example 1 40 Amount of acetone / part by weight Same as Example 1 Same as Example 1 0.5 Amount of polyether defoamer / part by weight Same as Example 1 Same as Example 1 0.3 Amount of amorphous calcium silicate hydrate / part by weight Same as Example 1 Same as Example 1 0 Amount of modified phenolic amine / part by weight Same as Example 1 Same as Example 1 43 Types of Secondary Amine Curing Agents Same as Example 1 Same as Example 1 0 Amount of the second amine curing agent / part by weight Same as Example 1 Same as Example 1 Same as Example 1

[0146] Test Case

[0147] Experiment on bond flexural strength after concrete crack repair (i.e. bond strength between epoxy resin grouting material and concrete matrix):

[0148] A 100mm×100mm×400mm cement mortar sample cured for 28 days was cut with a machine tool, and two cement mortar samples were placed with a 1mm interval to simulate cracks. The two sides (two sides perpendicular to the ground) of the two cement mortar samples with a 1mm interval were sealed with aluminum tape, leaving the upper surface grouting opening, and the epoxy resin grouting material prepared in Examples 1 to 9 and Comparative Examples 1 to Comparative Examples 8 was poured into the cracks. After the epoxy resin grouting material was poured for 7 days, the tape was removed and the sample was cut to obtain a cut sample A, ensuring that the epoxy resin grouting material in the cut sample A was sandwiched by the cement mortar, and the size of the cut sample A was 40mm*40mm*160mm. The cut sample A was subjected to an interface flexural strength test. This method can ensure that there is no excess coating of the epoxy resin grouting material on the surface of the cement mortar, ensuring the accuracy of the test results

[0149] In the dry bond flexural strength test, the cut surface of the 100mm×100mm×400mm cement mortar sample needs to be air-dried at room temperature for 1 day before the epoxy resin grouting material is poured; in the wet bond flexural strength test, the cut surface of the 100mm×100mm×400mm cement mortar sample needs to be soaked in water for 1 day, then the surface water is wiped off and the epoxy resin grouting material is poured. The bond durability test is to place the 40mm*40mm*160mm cut sample A in water for 28 days, 56 days, and 112 days before the bond flexural strength test.

[0150] After the cut sample A was left to stand at room temperature for 24 hours, the bonding flexural strength test was carried out at a loading speed of 50N / s. Each group of tests was performed three times, and the average of the three flexural strength results was taken. For specific results, see Table 4. For this test method, see the literature Yuan et al., Comparative study of reactive diluents with different molecular structures on the curing properties of epoxy adhesives and the interface bonding properties with mortar, International Journal of Adhesion and Adhesives, 126 (2023) 103473.

[0151] Viscosity and toughness test of epoxy resin grouting materials

[0152] The viscosity of the epoxy resin grouting materials prepared in Examples 1 to 9 and Comparative Examples 1 to 8 was measured using a NDJ-9S digital rotational viscometer (Shanghai Lichen Bangxi Instrument Technology Co., Ltd.) in accordance with the standard "Plastics-Resins in the liquid state or as emulsions or dispersions-Determination of apparent viscosity using a single cylinder type rotational viscometer method" ISO 2555:2018 (E). The results are the average of six measurements. The loading speed of the universal testing machine is 2 mm / min. When measuring the tensile specimen, a displacement extensometer is installed in the working section to continuously detect the displacement change. The test results are shown in Table 5.

[0153] According to the standard GB / T 2567-2008 "Test Method for Properties of Resin Castings", the toughness of epoxy resin grouting materials after curing for 7 days was measured and expressed as elongation at break. The test results are shown in Table 5.

[0154] Table 4

[0155]

[0156]

[0157] Table 5

[0158] Viscosity mPa·s Toughness (elongation at break)% Example 1 124 15.2 Example 2 173 11.6 Example 3 162 11.0 Example 4 197 10.2 Example 5 129 8.1 Example 6 196 9.3 Example 7 157 7.9 Example 8 153 8.1 Example 9 168 6.3 Comparative Example 1 321 3.2 Comparative Example 2 941 2.4 Comparative Example 3 864 2.8 Comparative Example 4 269 3.7 Comparative Example 5 342 4.9 Comparative Example 6 413 5.1 Comparative Example 7 585 5.3 Comparative Example 8 987 1.7

[0159] It can be seen from the results in Table 4 and Table 5 that the epoxy resin grouting material prepared by the present invention has better toughness and lower viscosity, and has good bonding strength and bonding durability with the concrete matrix.

[0160] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A method for preparing a modified epoxy resin, characterized in that: The method comprises: in a protective atmosphere, in the presence of a catalyst, heating a polyhydroxy compound and an epoxy resin at 80-100° C. to obtain a modified epoxy resin; The molar ratio of the polyhydroxy compound, the epoxy resin and the catalyst is 1:1-2:0.05-0.1; the epoxy resin is a bisphenol A epoxy resin; the catalyst is selected from any one of sodium hydroxide, potassium carbonate and dimethylaniline; the polyhydroxy compound is selected from at least one of glycerol, ethylene glycol, propylene glycol, glucose and butanediol.

2. The method according to claim 1, characterized in that The bisphenol A type epoxy resin is E51 type epoxy resin and / or E44 type epoxy resin.

3. The method according to claim 1 or 2, characterized in that: The conditions of the heating treatment include: a time of 6-12 hours and a stirring speed of 500-1000 rpm.

4. The modified epoxy resin prepared by the method described in any one of claims 1 to 3.

5. A composition for epoxy resin grouting material, characterized in that: In the composition, for every 100 parts by weight of the modified epoxy resin, the content of the first diluent is 20-30 parts by weight, the content of the second diluent is 1-3 parts by weight, the content of the first amine curing agent is 20-40 parts by weight, the content of the second amine curing agent is 5-10 parts by weight, the content of the defoaming agent is 0.1-0.2 parts by weight, and the content of the filler is 50-100 parts by weight; The first amine curing agent is a modified phenolic amine, and the amine value of the modified phenolic amine is 200-500KOH / g, and the viscosity at 25°C is 1-2Pa·s; the second amine curing agent is a hyperbranched polyamide with an intrinsic viscosity of 0.05-0.3g / dL; the first diluent is selected from at least one of polypropylene glycol diglycidyl ether, polyethylene oxide diglycidyl ether, 1,4-butanediol diglycidyl ether and 1,6-hexanediol diglycidyl ether; the second diluent is selected from at least one of ethanol, acetone and isopropanol; The modified epoxy resin is the modified epoxy resin according to claim 4.

6. The composition according to claim 5, characterized in that The hyperbranched polyamide has an intrinsic viscosity of 0.2-0.25 g / dL and a molecular weight of 3-4 kg / mol.

7. The composition according to claim 5 or 6, characterized in that The average particle diameter of the filler is less than 50 μm.

8. A method for preparing an epoxy resin grouting material, characterized in that: The method includes: (1) performing a first mixing process on a first diluent, a second diluent and a modified epoxy resin to obtain a mixture I; (2) subjecting the mixture I, the defoamer and the filler to a second mixing process to obtain a mixture II; (3) performing a third mixing process on the mixture II, the first amine curing agent and the second amine curing agent to obtain an epoxy resin grouting material; For every 100 parts by weight of the modified epoxy resin, the first diluent is used in an amount of 20-30 parts by weight, the second diluent is used in an amount of 1-3 parts by weight, the first amine curing agent is used in an amount of 20-40 parts by weight, the second amine curing agent is used in an amount of 5-10 parts by weight, the defoaming agent is used in an amount of 0.1-0.2 parts by weight, and the filler is used in an amount of 50-100 parts by weight; The first amine curing agent is a modified phenolic amine, and the amine value of the modified phenolic amine is 200-500KOH / g, and the viscosity at 25°C is 1-2Pa·s; the second amine curing agent is a hyperbranched polyamide with an intrinsic viscosity of 0.05-0.3g / dL; the first diluent is selected from at least one of polypropylene glycol diglycidyl ether, polyethylene oxide diglycidyl ether, 1,4-butanediol diglycidyl ether and 1,6-hexanediol diglycidyl ether; the second diluent is selected from at least one of ethanol, acetone and isopropanol; The modified epoxy resin is the modified epoxy resin according to claim 4.

9. The epoxy resin grouting material prepared by the method according to claim 8.

10. Use of the epoxy resin grouting material according to claim 9 in concrete.

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