Piperidine-bonded sealant for railway ballastless track and preparation method thereof

Abstract

The application discloses PBS piperidine bonding sealant for railway ballastless track and a preparation method thereof. The preparation raw materials of the A component include 30-50 parts of base resin A, 18-30 parts of light stabilizer, 0.1-0.3 parts of water removing agent I, 15-45 parts of filler I, 0.2-0.7 parts of pigment I and 0.3-0.5 parts of thixotropic agent in terms of weight. The preparation raw materials of the B component include 30-45 parts of crosslinking agent, 11-25 parts of coupling agent, 25-40 parts of base resin B, 2-21 parts of filler II, 0.1-0.3 parts of water removing agent II, 1-5 parts of pigment II and 0.1-0.3 parts of catalyst in terms of weight. The application has the advantages of high adhesion strength with concrete, high deformation capacity, stable high-low temperature performance, adaptability to a construction temperature range of-10 DEG C to 45 DEG C, stronger weather resistance and effective use for 30 years.

Description

TECHNICAL FIELD

[0001] The application relates to a PBS piperidine bonding sealant for a railway ballastless track and a preparation method thereof, and relates to C09J and specifically relates to preparation of silicon containing an oxygen group. BACKGROUND

[0002] The railway ballastless track is bonded with concrete, asphalt and other mixtures and the track, avoids flying of stone chippings on the ballast track, and the running speed of the railway on the ballastless track is high, so that the running speed, stability and comfort of the train can be improved. However, the bonding strength of the silicone glue jointing material between the track and the concrete is not high, the deformation ability is poor, and the silicone sealant is easy to fall off under the vibration of the high-speed train. In addition, the silicone sealant has poor high and low temperature resistance, and the temperature requirement for the construction environment is strict, so that the construction time is short, and the weather resistance of the sealant is poor, and the service life in the high and low temperature environment is only 1-2 years. In order to solve the above problems, the application develops a PBS (Piperidine bonding sealant) piperidine bonding silicone sealant which has high bonding strength with concrete and wide construction temperature range.

[0003] Chinese application patent CN201410251173.0 discloses a silicone jointing material for a ballastless track concrete expansion joint and a preparation method thereof, which realizes the double effects of deep curing of the silicone jointing material in the ballastless track concrete expansion joint and long-time storage by simultaneously adding a storage stabilizer and a deep curing agent, but the high and low temperature resistance of the silicone sealant is not improved. Chinese application patent CN201810516791.1 discloses a bonding promoter for a silicone sealant, a preparation method and application thereof and a silicone sealant applied to a ballastless track, which adopts a low-viscosity ketoxime-terminated polymer with a polyether-containing polyurethane main chain as the bonding promoter, has good flexibility and elongation; and also contains an urethane bond, so that the silicone sealant applied to the ballastless track has good flexibility and elongation, high viscosity and good bonding with the concrete base material, but the construction temperature range is narrow and the construction cannot be carried out in the high and low temperature environment. SUMMARY

[0004] In order to improve the bonding strength of the silicone sealant with concrete, expand the high and low temperature resistance range of the silicone sealant, and expand the construction temperature, the first aspect of the present application provides a PBS piperidine bonding sealant for railway ballastless track and a preparation method, which comprises a component A and a component B, and the preparation raw materials of the component A comprise, in terms of weight parts: base resin A 30-50 parts, light stabilizer 18-30 parts, water removing agent I 0.1-0.3 parts, filler I 15-45 parts, pigment I 0.2-0.7 parts, and thixotropic agent 0.3-0.5 parts; and the preparation raw materials of the component B comprise, in terms of weight parts: crosslinking agent 30-45 parts, coupling agent 11-25 parts, base resin B 25-40 parts, filler II 2-21 parts, water removing agent II 0.1-0.3 parts, pigment II 1-5 parts, and catalyst 0.1-0.3 parts.

[0005] As a preferred embodiment, the weight ratio of the component A to the component B is 1: (1-3).

[0006] The applicant found in the experiment that when the component A containing the base resin and the component B containing the crosslinking agent adopt the weight ratio of 1: (1-3), the prepared silicone sealant has a suitable curing speed and a wide construction temperature. The reason may be that under the preferred weight ratio, the silicone sealant has a suitable curing speed, and the shrinkage of the silicone sealant after curing is within a suitable range, and cracks are not easy to be generated under track vibration. In addition, the water removing agent is introduced in the system, which can remove the combined water in the raw materials, so that the crosslinking reaction can be smoothly carried out, and the water and small molecules cannot be discharged in time under a high construction temperature, which affects the structure of the silicone sealant, and the construction temperature range of the silicone sealant is widened.

[0007] As a preferred embodiment, the base resin A at least comprises silane and siloxane, and the molecular weight of the base resin A is 10000-20000 Da.

[0008] As a preferred embodiment, the base resin A is a combination of alpha, omega-dihydroxyl-terminated polydimethylsiloxane and silane-terminated polyether.

[0009] As a preferred embodiment, the weight ratio of the alpha, omega-dihydroxyl-terminated polydimethylsiloxane to the silane-terminated polyether is (15-25):(15-22).

[0010] The applicant found in the experiment that the silicone sealant prepared by using α, ω-dihydroxyl-terminated polydimethylsiloxane with a molecular weight of 10000-20000 Da and silane-terminated polyether together is suitable for the caulking of railway ballastless track and is not easy to fall off on the railway track. The possible reason is that α, ω-dihydroxyl-terminated polydimethylsiloxane with a molecular weight of 10000-20000 Da and silane-terminated polyether have suitable tensile strength and elongation, the prepared silicone sealant has certain toughness, can buffer part of the vibration brought by train operation when the silicone sealant is caulked between the track and the concrete, and the silicone sealant has certain deformability, avoiding falling off caused by train vibration. The base resin in the preferred molecular weight range also has certain pressure bearing capacity, plays a pressure bearing role between the rail and the concrete, and prevents the crack from increasing and being unable to recover after the track is extruded and deformed.

[0011] As a preferred embodiment, the light stabilizer is a combination of a hindered amine light stabilizer and a benzotriazole light stabilizer, and the weight ratio of the hindered amine light stabilizer to the benzotriazole light stabilizer is (18-28):(1.3-1.5).

[0012] As a preferred embodiment, the hindered amine light stabilizer is a piperidine derivative light stabilizer, and the piperidine derivative light stabilizer is selected from one of a tetramethylpiperidine light stabilizer or a pentamethylpiperidine light stabilizer.

[0013] As a preferred embodiment, the tetramethylpiperidine light stabilizer is selected from one or a combination of several of benzoic acid (2,2,6,6-tetramethyl-4-hydroxypiperidine) ester, azo tris[acetic acid (2,2,6,6-tetramethyl-4-hydroxypiperidine) ester], and N,N'-bis (2,2,6,6-tetramethylpiperidyl) hexanediamine, bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate.

[0014] As a preferred embodiment, the light stabilizer is a combination of bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate and 2'-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole.

[0015] The applicant found in the experiment that the combination of 2'-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole and bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate as a light stabilizer can improve the oxidation resistance of silicone sealant, and also increase the bonding strength of silicone sealant with concrete. The possible reason is that bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate contains 2,2,6,6-tetramethyl-4-piperidyl structure, which can be converted into nitroxyl radical under oxygen condition after absorbing light energy, and then capture the alkyl active free radicals generated by photolysis of silicone adhesive matrix resin, and then undergo reverse conversion to reduce the photolysis oxidation of silicone adhesive. When combined with 2'-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole, it can further absorb ultraviolet light, weaken the energy of ultraviolet light, and reduce the decomposition of silicone adhesive matrix resin by ultraviolet light. Under the combined action of 2'-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole and bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate, the piperidyl group can also bond with the hydroxyl group in the concrete, thereby increasing the bonding strength with the concrete.

[0016] As a preferred embodiment, the crosslinking agent is selected from one or a combination of methyltrimethoxysilane, vinyltris(butanoneoxime)silane, and methyltris(butanoneoxime)silane.

[0017] As a preferred embodiment, the crosslinking agent is a combination of methyltrimethoxysilane and vinyltris(butanoneoxime)silane.

[0018] As a preferred embodiment, the weight ratio of methyltrimethoxysilane to vinyltris(butanoneoxime)silane is (21-23):(10-18).

[0019] The applicant found in the experiment that the combination of methyltrimethoxysilane and vinyltris(butanoneoxime)silane as a crosslinking agent can improve the deformation ability of silicone sealant, and the performance is stable in high and low temperature environment. The possible reason is that the branched structure of methyltrimethoxysilane and vinyltris(butanoneoxime)silane can increase the crosslinking sites between the base resin, improve the crosslinking density, and form silicone sealant containing more saturated branched structure. The molecular chain is soft and has large shrinkage, and the branched molecular structure is small, the space resistance between molecules is small, and the regularity of molecular structure is low, so the activity of chain segment is high, so that the prepared silicone sealant has certain deformation ability. In low temperature environment, the irregularity of chain segment reduces the glass transition temperature of silicone adhesive, so that it has good high and low temperature resistance.

[0020] As a preferred embodiment, the coupling agent is selected from one or a combination of mercaptopropyltrimethoxysilane, methyltris(butanoneoxime)silane, tetrakis(butanoneoxime)silane, phenyltris(butanoneoxime)silane, N-phenyl-3-aminopropyltrimethoxysilane.

[0021] As a preferred embodiment, the coupling agent is selected from one or a combination of mercaptopropyltrimethoxysilane, methyltris(butanoneoxime)silane, tetrakis(butanoneoxime)silane, phenyltris(butanoneoxime)silane, N-phenyl-3-aminopropyltrimethoxysilane.

[0022] As a preferred embodiment, the coupling agent is selected from one or a combination of mercaptopropyltrimethoxysilane, methyltris(butanoneoxime)silane, tetrakis(butanoneoxime)silane, phenyltris(butanoneoxime)silane, N-phenyl-3-aminopropyltrimethoxysilane.

[0023] As a preferred embodiment, the coupling agent is selected from one or a combination of mercaptopropyltrimethoxysilane, methyltris(butanoneoxime)silane, tetrakis(butanoneoxime)silane, phenyltris(butanoneoxime)silane, N-phenyl-3-aminopropyltrimethoxysilane.

[0024] As a preferred embodiment, the coupling agent is selected from one or a combination of mercaptopropyltrimethoxysilane, methyltris(butanoneoxime)silane, tetrakis(butanoneoxime)silane, phenyltris(butanoneoxime)silane, N-phenyl-3-aminopropyltrimethoxysilane.

[0025] As a preferred embodiment, the coupling agent is selected from one or a combination of mercaptopropyltrimethoxysilane, methyltris(butanoneoxime)silane, tetrakis(butanoneoxime)silane, phenyltris(butanoneoxime)silane, N-phenyl-3-aminopropyltrimethoxysilane.

[0026] As a preferred embodiment, the coupling agent is selected from one or a combination of mercaptopropyltrimethoxysilane, methyltris(butanoneoxime)silane, tetrakis(butanoneoxime)silane, phenyltris(butanoneoxime)silane, N-phenyl-3-aminopropyltrimethoxysilane.

[0027] As a preferred embodiment, the silicone sealant has a construction temperature range of -10~45℃.

[0028] The second aspect of the present application provides a preparation method of PBS piperidine bonding sealant for railway ballastless track and preparation method, comprising the following steps:

[0029] (1) mixing and stirring the preparation raw materials of the A component uniformly, increasing the temperature, reacting, and vacuumizing while stirring, and keeping the reaction to obtain the A component;

[0030] (2) Mix and stir the raw materials for the preparation of component B evenly, raise the temperature, react, and keep the reaction under vacuum while stirring to obtain component B;

[0031] (3) Mix component A and component B according to the weight ratio, stir evenly, and then use.

[0032] As a preferred embodiment, the method for preparing the PBS piperidine bonding sealant for ballastless railway tracks includes the following steps:

[0033] (1) Add base resin A to the reactor and stir evenly; add filler I, titanium dioxide and thixotropic agent and stir evenly; add dehydrating agent I, heat to 115-125℃, stir and vacuum at the same time, and keep for 3-5 hours; cool down to 70-90℃, add light stabilizer and carbon black and stir, stir and vacuum at the same time, and keep for 1-2 hours to obtain component A;

[0034] (2) Add crosslinking agent, coupling agent, base resin B, filler II, dehydrating agent II and pigment II to the reactor and stir evenly; heat to 115-125℃, stir and vacuum for 3-5 hours; cool to room temperature, add catalyst, stir and vacuum for 1-2 hours to obtain component B.

[0035] (3) Mix component A and component B according to the weight ratio, stir evenly, and then use.

[0036] As a preferred embodiment, the silicone sealant described in this application can be a two-component adhesive, or it can be a one-component adhesive formed by adding dioctyl phthalate.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] (1) The PBS piperidine bonded sealant for railway ballastless track described in this invention has a light stabilizer consisting of a combination of 2'-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole and bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate in a weight ratio of (1.3-1.5):(18-28), which improves the antioxidant properties of the silicone sealant and increases the bonding strength between the silicone sealant and concrete.

[0039] (2) The PBS piperidine bonded sealant for railway ballastless tracks described in this invention has a matrix resin A that is a combination of α,ω-dihydroxy-terminated polydimethylsiloxane and silane-terminated polyether with a molecular weight of 10,000-20,000 Da, which can buffer the vibration of high-speed trains and reduce the detachment of silicone sealant from railway tracks.

[0040] (3) The PBS piperidine bonding sealant for railway ballastless track has the advantages that methyltrimethoxysilane and vinyl tributylketoximosilane are used as the combination of crosslinking agents, the weight ratio is (21-23):(10-18), and the prepared silicone sealant has deformation capacity and stable performance in high and low temperature environments.

[0041] (4) The PBS piperidine bonding sealant for railway ballastless track has the advantages that the weight ratio of component A containing the base resin to component B containing the crosslinking agent is 1:(1-3), and the prepared silicone sealant has a suitable curing speed and a wide construction temperature.

[0042] (5) The PBS piperidine bonding sealant for railway ballastless track has the advantages of high adhesion strength with concrete, high deformation capacity, stable high and low temperature performance, adaptability to a construction temperature range of-10 DEG C to 45 DEG C, and stronger weather resistance, and can be effectively used for 30 years. BRIEF DESCRIPTION OF DRAWINGS

[0043] Figure 1 It is an application picture of the PBS piperidine bonding sealant in example 1 to high-speed rail section line interval sealing layer expansion joint filling treatment;

[0044] Figure 2 It is an application picture of the PBS piperidine bonding sealant in example 1 to passenger dedicated line interval sealing layer expansion joint filling treatment;

[0045] Figure 3 It is an application picture of the PBS piperidine bonding sealant in example 1 to airport intercity track bed expansion joint filling treatment;

[0046] Figure 4 It is an application picture of the PBS piperidine bonding sealant in example 1 to subway track bed expansion joint filling treatment;

[0047] Figure 5 It is an application picture of the PBS piperidine bonding sealant in example 1 to county intercity track bed expansion joint filling treatment;

[0048] Figure 6 It is an application picture of the PBS piperidine bonding sealant in example 1 to railway crossing concrete pavement expansion joint filling treatment. DETAILED DESCRIPTION

[0049] EMBODIMENT

[0050] A PBS piperidine bonding sealant for railway ballastless track and a preparation method, preparation raw materials and components are shown in table 1 and table 2:

[0051] Table 1

[0052]

[0053] Table 2

[0054]

[0055] The α,ω-dihydroxyl-terminated polydimethylsiloxane was purchased from Bluestar East; the silane-terminated polyether was purchased from Asahi, model S888E.

[0056] A PBS piperidine bonding sealant for railway ballastless track and a preparation method, comprising the following steps:

[0057] (1) The base resin A is added to the reaction kettle, and after stirring uniformly, the filler I, titanium dioxide and thixotropic agent are added, and stirred uniformly; the water removing agent I is added, the temperature is raised to 120°C, and the vacuum is extracted while stirring, and maintained for 4 hours; the temperature is lowered to 80°C, the light stabilizer and carbon black are added and stirred, and the vacuum is extracted while stirring, and maintained for 1 hour, to obtain the component A;

[0058] (2) The crosslinking agent, coupling agent, base resin B, filler II, water removing agent II and pigment II are added to the reaction kettle, and stirred uniformly; the temperature is raised to 120°C, and the vacuum is extracted while stirring, and maintained for 4 hours; the temperature is lowered to 25°C, the catalyst is added and stirred, and the vacuum is extracted while stirring, and maintained for 1 hour, to obtain the component B;

[0059] (3) The component A and the component B are mixed according to the weight ratio, and can be used after stirring uniformly.

[0060] The weight ratio of the component A and the component B in examples 1 and 2 is 1:2.

[0061] In example 3, the component A, the component B and dioctyl phthalate are mixed according to the weight ratio of 1:2:0.1, to obtain a single-component material.

[0062] Performance test

[0063] The detection is carried out according to the detection method required by the specification of Q / CR601-2017 "Railway ballastless track caulking material", and the results are as follows, the test results of example 1 are shown in table 3, the test results of example 2 are shown in table 4, and the test results of example 3 are shown in table 5.

[0064] Table 3

[0065]

[0066] Table 4

[0067]

[0068] Table 5

[0069]

[0070] Embodiments 1-3 are suitable for average monthly temperatures ≥ -20°C. When the average monthly low temperature is below -20°C, the piperidine-bonded silicone sealant of the present application can be adapted to engineering deformation in cold regions, and the final performance meets the technical index.

Claims

1. A piperidine-bonded sealant for railway ballastless track, characterized by, It comprises a component A and a component B, the raw materials for preparing the component A include, by weight, 30-50 parts of base resin A, 18-30 parts of light stabilizer, 0.1-0.3 parts of water removing agent I, 15-45 parts of filler I, 0.2-0.7 parts of pigment I, and 0.3-0.5 parts of thixotropic agent; the raw materials for preparing the component B include, by weight, 30-45 parts of crosslinking agent, 11-25 parts of coupling agent, 25-40 parts of base resin B, 2-21 parts of filler II, 0.1-0.3 parts of water removing agent II, 1-5 parts of pigment II, and 0.1-0.3 parts of catalyst; The base resin A is a combination of α, ω-dihydroxyl-terminated polydimethylsiloxane and silane-terminated polyether, with a weight ratio of (15-25):(15-22); the molecular weight of the base resin A is 10000-20000 Da; The base resin B is a combination of dicyclohexylmethane diisocyanate and isocyanate propyl triethoxysilane, with a weight ratio of (10-20):(15-20); The light stabilizer is a combination of bis(2, 2, 6, 6-tetramethyl-4-piperidyl) sebacate and 2'-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole, with a weight ratio of (18-28):(1.3-1.5); The crosslinking agent is a combination of methyl trimethoxysilane and vinyl tributyl ketoximosilane, with a weight ratio of (21-23):(10-18); The weight ratio of the component A and the component B is 1:(1-3).

2. The piperidine-linked sealant for railway ballastless track according to claim 1, wherein The coupling agent is selected from one or a combination of several of mercaptopropyl trimethoxysilane, methyl tributyl ketoximosilane, tetrabutyl ketoximosilane, phenyl tributyl ketoximosilane, and N-phenyl-3-aminopropyl trimethoxysilane.

3. The piperidine-linked sealant for railway ballastless track according to claim 1, wherein The construction temperature range of the piperidine-bonded sealant is -10-45℃.

4. A process for the preparation of a piperidine-bonded sealant for railway ballastless track according to any one of claims 1 to 3, characterized in that It comprises the following steps: (1) mixing and stirring the raw materials for preparing the component A uniformly, increasing the temperature, reacting, and keeping the reaction by stirring and vacuumizing to obtain the component A; (2) mixing and stirring the raw materials for preparing the component B uniformly, increasing the temperature, reacting, and keeping the reaction by stirring and vacuumizing to obtain the component B; (3) mixing the component A and the component B according to the weight ratio, stirring uniformly, and then using.

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