Silicone colorant for rail transportation and method for preparing the same

Abstract

The application discloses a kind of organic silicon colorant for rail transit and preparation method thereof, belong to fine chemical technology field, its technical scheme main point is a kind of organic silicon colorant for rail transit, the organic silicon colorant includes the following weight parts of raw material: modified inorganic pigment 45-55 parts, silicon oil 30-45 parts, dispersing agent 3-8 parts;The modified inorganic pigment is obtained by following modification method: inorganic pigment is ultrasonically dispersed in water, then add sepiolite powder and ultrasonically dispersed for 50-60min under the condition that temperature is 40-50 ℃, then add amino silane coupling agent and form suspension after ultrasonically dispersed, then, under the condition that temperature is 70-100 ℃, reaction 0.5-1.5h, after reaction is completed, centrifugal, washing, drying, grinding is ground to 200 mesh screen after modification inorganic pigment is obtained, reach the technical effect of solving inorganic pigment easy formation aggregate and cause poor coloring performance.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of fine chemical technology, in particular to an organic silicon colorant for rail transit and a preparation method thereof. BACKGROUND

[0002] Organic silicon compounds and the organic silicon materials prepared therefrom have unique functions and have been widely used in national defense, industry, agriculture, medical and health care, rail transit and other industries, and have shown irreplaceable advantages. In the field of rail transit, organic silicon rubber is colored in vehicle coating and road marking materials, and the selection of appropriate colorants is the key to improving the appearance and overall quality of organic silicon products.

[0003] Pigments of various colors adorn the colorful world, and are also indispensable in the field of rail transit. The colorants used in organic silicon rubber include inorganic pigments and organic pigments. Organic pigment colorants have bright colors, strong coloring ability and no toxicity, but the migration resistance, heat resistance and light resistance of organic pigments are poorer than those of inorganic pigments. Therefore, inorganic pigments have better thermal stability and weather resistance than organic pigments, and play an important role in the coloring of organic silicon rubber. However, the compatibility between inorganic pigments and resins is poor, which leads to poor dispersion of inorganic pigments in resins, thereby causing the problem of reduced coloring ability in the application process of inorganic pigments. SUMMARY

[0004] In order to solve the problem of poor coloring performance caused by the easy formation of agglomerates of inorganic pigments, the present application provides an organic silicon colorant for rail transit and a preparation method thereof.

[0005] The first aspect of the present application is to provide an organic silicon colorant for rail transit, which adopts the following technical solution:

[0006] An organic silicon colorant for rail transit, the organic silicon colorant comprises the following raw materials by weight: modified inorganic pigment 45-55 parts, silicone oil 30-45 parts, dispersant 3-8 parts; the modified inorganic pigment is obtained by the following modification method: ultrasonic dispersion of inorganic pigment in water, then adding sepiolite powder under the condition of temperature 45±5℃ ultrasonic dispersion for 50-60min, then adding amino silane coupling agent to form a suspension after ultrasonic dispersion, and then reacting under the condition of temperature 70-100℃ for 0.5-1.5h, after the reaction is completed, centrifugation, washing, drying and grinding through a 200 mesh sieve to obtain the modified inorganic pigment.

[0007] By adopting the technical scheme, the compatibility between the inorganic pigment and the silicone oil can be effectively improved after the inorganic pigment is improved by the sepiolite powder and the amino silane coupling agent. After the organic silicone colorant obtained by the application is applied in the organic silicone resin, the organic silicone colorant can be uniformly dispersed in the organic silicone resin. The reason is that the sepiolite powder provides a good adhesion substrate for the dispersion of the inorganic pigment after the inorganic pigment and the sepiolite powder are dispersed by ultrasonic, so that the inorganic pigment is adsorbed on the surface of the sepiolite powder under the action of electrostatic adsorption and hydrogen bond, and the dispersion performance of the inorganic pigment is improved. Then, after the adsorbed sepiolite powder and the amino silane coupling agent are reacted at high temperature, part of the silicon hydroxyl generated by the hydrolysis of the reaction groups in the amino silane coupling agent reacts with the active hydroxyl on the surface of the sepiolite by condensation dehydration reaction. It can be seen that the amino silane coupling agent reacts with the active groups on the surface of the sepiolite powder to form a stable chemical bond. This chemical bond not only helps to enhance the interfacial bonding force between the sepiolite powder and the amino silane coupling agent, thereby improving the compatibility between the sepiolite powder and the silicone oil, and providing strong support for the dispersion and stability of the inorganic pigment particles. Therefore, a stable composite system is formed among the sepiolite powder, the amino coupling agent and the inorganic pigment particles, and the presence of the amino silane coupling agent effectively reduces the separation between the inorganic pigment and the sepiolite powder, and improves the storage stability of the organic silicone colorant.

[0008] In a preferred embodiment, the weight ratio of the inorganic pigment, the sepiolite powder and the amino silane coupling agent is 1:(0.4-0.7):(0.05-0.2).

[0009] In a preferred embodiment, the amino silane coupling agent is one of 3-aminopropyltrimethoxysilane and 3-aminopropyltriethoxysilane.

[0010] In a preferred embodiment, the sepiolite powder is obtained by the following modification method. The sepiolite powder is added into hydrochloric acid with a concentration of 1.8-3.2 mol / L and stirred for 5-6 h, then washed with water until neutral and the chloride ion content is less than 0.001%, and then dried at 80-90°C after centrifugal separation, and then crushed to pass through a 200-mesh screen to obtain modified sepiolite powder. The solid-liquid ratio of the sepiolite powder and the hydrochloric acid is 1 g:(7-10) mL.

[0011] By adopting the technical scheme, after the sepiolite powder is subjected to acid modification treatment, the multiple carbonate impurities in the sepiolite channel are removed, the sepiolite channel is dredged, the structure units can be interconnected, more reactive sites in the sepiolite are provided, the adsorption of the inorganic pigment on the sepiolite is facilitated, and the dispersion efficiency of the inorganic pigment is improved; in the process of acid modification of the sepiolite powder, if the concentration of the acid is too high, the structure of the sepiolite is damaged, and if the concentration of the acid is too low, the acid radical ion reacts with the magnesium ion in the sepiolite to generate a precipitate, which blocks the channel and affects the efficient use of the sepiolite, therefore, the concentration of the hydrochloric acid in the application is 1.8-3.2 mol / L, which ensures the efficient adsorption of the inorganic pigment on the modified sepiolite powder.

[0012] In a preferred embodiment, the silicone oil is obtained by modifying the silicone oil by mixing the silicone oil and water in a weight ratio of 1:2, then adding a composite emulsifier with a weight percentage of 35% of the silicone oil to react at a temperature of 45±5°C for 40±5min, and then adjusting the pH of the emulsion to 6.5 to obtain the modified silicone oil, wherein the composite emulsifier is composed of Tween 80 and AEO-9 in a weight ratio of 0.5:0.4.

[0013] By adopting the technical scheme, after the silicone oil is subjected to modification treatment by the composite emulsifier, the compatibility between the silicone oil and the sepiolite powder is increased, the dispersion capacity of the colorant is improved, and the coloring capacity is improved.

[0014] In a preferred embodiment, the dispersant is composed of a high-molecular dispersant and a styrene-maleic anhydride copolymer in a weight ratio of 1:(0.8-1.6).

[0015] By adopting the technical scheme, when the dispersant is composed of the high-molecular dispersant and the styrene-maleic anhydride copolymer, the dispersion performance and the stability of the inorganic pigment in the silicone resin can be significantly improved, because the sepiolite powder has a certain adsorption effect on the styrene-maleic anhydride copolymer, the molecular chain of the styrene-maleic anhydride copolymer is arranged in an ordered manner on the surface of the sepiolite powder, the ordered arrangement structure improves the thermal stability of the silicone colorant, the obtained silicone colorant has certain heat resistance, the effect of the surface amino silane further improves the adhesion stability of the inorganic pigment on the sepiolite, the anchoring groups contained in the high-molecular dispersant can provide a steric hindrance effect on the surface of the sepiolite powder, the possibility of aggregation of the sepiolite powder is reduced, and the silicon-containing groups in the high-molecular dispersant further improve the dispersion performance of the sepiolite powder in the silicone oil.

[0016] In a preferred embodiment, the styrene-maleic anhydride copolymer is obtained by using a modification method as follows: under the protection of nitrogen atmosphere, toluene, catalyst, styrene-maleic anhydride copolymer, isobutyl alcohol are mixed, and constant temperature reaction is carried out at 80±5℃ for 5-6h; after the reaction is completed, the product is rotary evaporated to remove toluene, and then precipitated in petroleum ether to obtain precipitate; the precipitate is vacuum dried at 30℃ to obtain the modified styrene-maleic anhydride copolymer, and the mass ratio of the styrene-maleic anhydride copolymer to isobutyl alcohol is 1:(2-2.5).

[0017] By using the above technical solution, the heat stability of the organic silicone colorant can be improved after the styrene-maleic anhydride copolymer is esterified by isobutyl alcohol, and the reason may be that the ester group is introduced into the copolymer molecular chain after the esterification reaction of the styrene-maleic anhydride copolymer, the compatibility with the high molecular dispersant is improved, the synergistic dispersion effect is better, on the other hand, the ester group is combined with the polar group on the surface of the inorganic pigment through the action of hydrogen bond, and based on the adsorption of sepiolite, the styrene-maleic anhydride copolymer is wrapped around the modified pigment to form a protective layer, so as to block the harmful factors such as oxygen and moisture in the high temperature environment from directly contacting with the inorganic pigment, thereby slowing down the thermal oxidation or hydrolysis process of the inorganic pigment, and improving the heat stability of the organic silicone coloring.

[0018] In a preferred embodiment, the catalyst uses p-toluenesulfonic acid.

[0019] In a preferred embodiment, the high molecular dispersant is obtained by using a preparation method as follows: isooctyl acrylate, toluene and azobisisobutyronitrile are mixed, heated and stirred to 85±2℃, then a mixed monomer solution of methyl methacrylate and vinyltrimethoxysilane is added dropwise, after the dropwise addition is completed, azobisisobutyronitrile is added, and the temperature is kept at 85±2℃ for 5-6h, then the product is precipitated with methanol, and the precipitate is vacuum dried to obtain the high molecular dispersant, and the weight ratio of isooctyl acrylate, methyl methacrylate and vinyltrimethoxysilane is 2:1:1.

[0020] By using the above technical solution, when the monomers are selected as isooctyl acrylate, methyl methacrylate and vinyltrimethoxysilane and the weight ratio is 2:1:1, the high molecular dispersant can be effectively grafted on the surface of sepiolite powder to effectively wrap the sepiolite powder, so as to prevent the mutual attraction between particles, realize the effective dispersion of sepiolite powder in silicone oil, and maintain the stable dispersion state of sepiolite powder particles.

[0021] The second aspect of the present application provides a preparation method of an organic silicone colorant for rail transit, comprising the following steps:

[0022] S1, modified inorganic pigment and dispersant are added into silicone oil and stirred and mixed;

[0023] S2, grinding the mixture obtained in step S1 at a temperature of 50-60℃ for 20-30min to obtain the silicone colorant for rail transit.

[0024] In summary, the present application has the following beneficial effects:

[0025] 1. After the sepiolite powder adsorbed with inorganic pigments is modified by the amino silane coupling agent, the dispersion stability of the inorganic pigments is improved, so that the color capacity of the silicone colorant is improved. Furthermore, the chemical bond between the amino silane coupling agent and the sepiolite powder helps the sepiolite powder to be uniformly dispersed in the silicone oil, so that the heat resistance and insulation performance of the silicone colorant can be effectively improved.

[0026] 2. The synergistic cooperation of the high molecular dispersant prepared in a specific way and the modified styrene-maleic anhydride copolymer promotes the uniform dispersion of the inorganic pigments in the silicone resin. At the same time, the anhydride groups in the styrene-maleic anhydride copolymer and the modified inorganic pigment surface and the sepiolite powder have a chemical effect, forming a stable chemical bond, further enhancing the dispersion stability of the inorganic pigment particles. Moreover, the cooperation of the styrene-maleic anhydride copolymer and the sepiolite powder makes the silicone colorant have good heat resistance. DETAILED DESCRIPTION

[0027] The present application will be further described in detail below in combination with examples.

[0028] The raw materials used in the present application are all from the market.

[0029] A silicone colorant for rail transit, the silicone colorant comprises the following raw materials in parts by weight: modified inorganic pigments 45-55 parts, silicone oil 30-45 parts, dispersant 3-8 parts; the modified inorganic pigments are obtained by the following modification method: ultrasonic dispersion of inorganic pigments in water, then adding sepiolite powder and ultrasonic dispersion for 50-60min at a temperature of 45±5℃, then adding amino silane coupling agent to form a suspension, and then reacting at a temperature of 70-100℃ for 0.5-1.5h, after the reaction is completed, centrifugation, washing, drying, and grinding through a 200 mesh sieve to obtain the modified inorganic pigments.

[0030] In a preferred embodiment, the weight ratio of inorganic pigments to sepiolite powder to amino silane coupling agent is 1:(0.4-0.7):(0.05-0.2).

[0031] In a preferred embodiment, the amino silane coupling agent is one of 3-aminopropyltrimethoxysilane and 3-aminopropyltriethoxysilane.

[0032] In a preferred embodiment, the modified method for obtaining the sepiolite powder is as follows: the sepiolite powder is stirred in hydrochloric acid with a concentration of 1.8-3.2 mol / L for 5-6 h, then washed with water until neutral and the chloride ion content is less than 0.001%, and then dried at 80-90°C after centrifugal separation, and then crushed to pass through a 200 mesh screen to obtain the modified sepiolite powder.

[0033] In a preferred embodiment, the ratio of sepiolite powder to hydrochloric acid is 1 g:(7-10) mL.

[0034] In a preferred embodiment, the modified method for obtaining the silicone oil is as follows: the silicone oil and water are mixed in a weight ratio of 1:2, then a complex emulsifier with a weight percentage of 35% of the silicone oil is added, and the reaction is carried out at a temperature of 45±5°C for 40±5 min, then the pH of the emulsion is adjusted to 6.5 to obtain the modified silicone oil, wherein the complex emulsifier is composed of Tween 80 and AEO-9 in a weight ratio of 0.5:0.4.

[0035] In a preferred embodiment, the dispersant is composed of a high molecular dispersant and a styrene-maleic anhydride copolymer in a weight ratio of 1:(0.8-1.6).

[0036] In a preferred embodiment, the modified method for obtaining the styrene-maleic anhydride copolymer is as follows: under the protection of nitrogen atmosphere, toluene, a catalyst, the styrene-maleic anhydride copolymer, and isobutyl alcohol are mixed, and the reaction is carried out at a constant temperature of 80±5°C for 5-6 h, then the product is rotary evaporated to remove toluene, and then the precipitate is obtained by precipitating in petroleum ether, and then the precipitate is vacuum dried at 30°C to obtain the modified styrene-maleic anhydride copolymer, wherein the mass ratio of the styrene-maleic anhydride copolymer to isobutyl alcohol is 1:(2-2.5).

[0037] In a preferred embodiment, the catalyst is p-toluenesulfonic acid.

[0038] In a preferred embodiment, the preparation method for obtaining the high molecular dispersant is as follows: isooctyl acrylate, toluene, and azobisisobutyronitrile are mixed, heated to 85±2°C while stirring, then a mixed monomer solution of methyl methacrylate and vinyltrimethoxysilane is added dropwise, after the dropwise addition is completed, azobisisobutyronitrile is added, and the reaction is carried out at a temperature of 85±2°C for 5-6 h, then the product is precipitated in methanol, and then the precipitate is vacuum dried to obtain the high molecular dispersant, wherein the weight ratio of isooctyl acrylate, methyl methacrylate, and vinyltrimethoxysilane is 2:1:1.

[0039] A preparation method of an organic silicone colorant for rail transit, comprising the following steps:

[0040] S1, the modified inorganic pigment and the dispersant are added to the silicone oil and stirred and mixed;

[0041] S2, grinding the mixture obtained in step S1 at a temperature of 50-60℃ for 20-30 min to obtain a silicone colorant for rail transit.

[0042] The inorganic pigments in the following preparation examples and examples of the present application are illustrated by taking yellow iron oxide as an example. The styrene-maleic anhydride copolymer in the preparation examples and examples of the present application is purchased from Guangzhou Sun Sun New Material SMA125.

[0043] Preparation Example 1.1

[0044] A modified inorganic pigment modification method: comprising the following steps: ultrasonic dispersion of the inorganic pigment in water for 20 min, then adding sepiolite powder and ultrasonic dispersion for 50 min at a temperature of 40℃, then adding 3-aminopropyltrimethoxysilane to form a suspension, stirring for 30 min, then reacting at a temperature of 70℃ for 0.5h, after the reaction is completed, centrifugation, washing, drying, and grinding through a 200 mesh screen to obtain the modified inorganic pigment, wherein the weight ratio of the inorganic pigment, sepiolite powder, and 3-aminopropyltrimethoxysilane is 1:0.4:0.05.

[0045] Preparation Example 1.2

[0046] A modified inorganic pigment modification method: comprising the following steps: ultrasonic dispersion of the inorganic pigment in water for 20 min, then adding sepiolite powder and ultrasonic dispersion for 55 min at a temperature of 50℃, then adding 3-aminopropyltrimethoxysilane to form a suspension, stirring for 25 min, then reacting at a temperature of 70℃ for 0.5h, after the reaction is completed, centrifugation, washing, drying, and grinding through a 200 mesh screen to obtain the modified inorganic pigment, wherein the weight ratio of the inorganic pigment, sepiolite powder, and 3-aminopropyltrimethoxysilane is 1:0.6:0.12.

[0047] Preparation Example 1.3

[0048] A modified inorganic pigment modification method: comprising the following steps: ultrasonic dispersion of the inorganic pigment in water for 20 min, then adding sepiolite powder and ultrasonic dispersion for 60 min at a temperature of 50℃, then adding 3-aminopropyltrimethoxysilane to form a suspension, stirring for 35 min, then reacting at a temperature of 70℃ for 0.5h, after the reaction is completed, centrifugation, washing, drying, and grinding through a 200 mesh screen to obtain the modified inorganic pigment, wherein the weight ratio of the inorganic pigment, sepiolite powder, and 3-aminopropyltrimethoxysilane is 1:0.7:0.2.

[0049] Preparation Example 1.4

[0050] A modified inorganic pigment modification method: different from Preparation Example 1.2 is that the reaction temperature is 80°C for 1 h, after the reaction is completed, centrifugation, washing, drying, grinding through a 200 mesh sieve to obtain a modified inorganic pigment, and the others are the same as Preparation Example 1.2.

[0051] Preparation Example 1.5

[0052] A modified inorganic pigment modification method: different from Preparation Example 1.2 is that the reaction temperature is 80°C for 1 h, after the reaction is completed, centrifugation, washing, drying, grinding through a 200 mesh sieve to obtain a modified inorganic pigment, and the others are the same as Preparation Example 1.2.

[0053] Preparation Example 1.6

[0054] A modified inorganic pigment modification method: different from Preparation Example 1.4 is that the sepiolite powder is modified sepiolite powder, and the modification method of the modified sepiolite powder comprises the following steps: the sepiolite powder is added to hydrochloric acid with a concentration of 1.8 mol / L and stirred for 5 h, then washed with water until neutral and the chloride ion content is less than 0.001%, centrifuged, dried at 80°C, and ground through a 200 mesh sieve to obtain the modified sepiolite powder, wherein the solid-liquid ratio of the sepiolite powder to the hydrochloric acid is 1:7 g / ml.

[0055] Preparation Example 1.7

[0056] A modified inorganic pigment modification method: different from Preparation Example 1.4 is that the sepiolite powder is modified sepiolite powder, and the modification method of the modified sepiolite powder comprises the following steps: the sepiolite powder is added to hydrochloric acid with a concentration of 1.8 mol / L and stirred for 5 h, then washed with water until neutral and the chloride ion content is less than 0.001%, centrifuged, dried at 80°C, and ground through a 200 mesh sieve to obtain the modified sepiolite powder, wherein the solid-liquid ratio of the sepiolite powder to the hydrochloric acid is 1:7 g / ml.

[0057] Preparation Example 1.8

[0058] A modified inorganic pigment modification method: different from Preparation Example 1.4 is that the sepiolite powder is modified sepiolite powder, and the modification method of the modified sepiolite powder comprises the following steps: the sepiolite powder is added to hydrochloric acid with a concentration of 1.8 mol / L and stirred for 5 h, then washed with water until neutral and the chloride ion content is less than 0.001%, centrifuged, dried at 80°C, and ground through a 200 mesh sieve to obtain the modified sepiolite powder, wherein the solid-liquid ratio of the sepiolite powder to the hydrochloric acid is 1:7 g / ml.

[0059] Preparation Example 1.9

[0060] A modified inorganic pigment modification method: different from Preparation Example 1.7 is that the sepiolite powder is replaced by modified sepiolite powder, the liquid ratio of sepiolite powder to hydrochloric acid is 1:10 g / ml, and the others are the same as Preparation Example 1.7.

[0061] Comparative Preparation Example 1.1

[0062] A modified inorganic pigment modification method: different from Preparation Example 1.4 is that the same amount of attapulgite is used instead of sepiolite powder, and the others are the same as Preparation Example 1.4.

[0063] Comparative Preparation Example 1.2

[0064] A modified inorganic pigment modification method: different from Preparation Example 1.4 is that the same amount of vinyl triethoxysilane is used instead of 3-aminopropyl trimethoxysilane, and the others are the same as Preparation Example 1.4.

[0065] Comparative Preparation Example 1.3

[0066] A modified inorganic pigment modification method: different from Preparation Example 1.4 is that no sepiolite powder is added during modification, and the others are the same as Preparation Example 1.4.

[0067] Comparative Preparation Example 1.4

[0068] A modified inorganic pigment modification method: different from Preparation Example 1.4 is that no 3-aminopropyl trimethoxysilane is added during modification, and the others are the same as Preparation Example 1.4.

[0069] Preparation Example 2.1

[0070] A modified styrene-maleic anhydride copolymer modification method includes the following steps: under the protection of nitrogen atmosphere, 80 mL of toluene, 0.1 g of p-toluenesulfonic acid, 6 g of styrene-maleic anhydride copolymer, and 12 g of isobutyl alcohol are mixed, and the reaction is carried out at 80°C for 5 hours. After the reaction is completed, the product is rotary evaporated to remove toluene, then precipitated in petroleum ether to obtain a precipitate, and the precipitate is vacuum dried at 30°C to obtain the modified styrene-maleic anhydride copolymer.

[0071] Preparation Example 2.2

[0072] A modified styrene-maleic anhydride copolymer modification method includes the following steps: under the protection of nitrogen atmosphere, 80 mL of toluene, 0.1 g of p-toluenesulfonic acid, 6 g of styrene-maleic anhydride copolymer, and 13.8 g of isobutyl alcohol are mixed, and the reaction is carried out at 85°C for 5 hours. After the reaction is completed, the product is rotary evaporated to remove toluene, then precipitated in petroleum ether to obtain a precipitate, and the precipitate is vacuum dried at 30°C to obtain the modified styrene-maleic anhydride copolymer.

[0073] Preparation Example 2.3

[0074] The modification method of styrene-maleic anhydride copolymer comprises the following steps: mixing 80 mL of toluene, 0.1 g of p-toluenesulfonic acid, 6 g of styrene-maleic anhydride copolymer, and 15 g of isobutyl alcohol under the protection of nitrogen atmosphere, and reacting at 85°C for 5 h. After the reaction is completed, the product is rotary evaporated to remove toluene, and then precipitated in petroleum ether to obtain a precipitate. The precipitate is vacuum dried at 30°C to obtain the modified styrene-maleic anhydride copolymer.

[0075] Preparation Example 3.1

[0076] The preparation method of the high molecular dispersant comprises the following steps: mixing isooctyl acrylate, toluene, and azobisisobutyronitrile, stirring and heating to 85±2°C, then adding a mixed monomer solution of methyl methacrylate and vinyltrimethoxysilane dropwise, adding azobisisobutyronitrile again after the dropwise addition is completed, and reacting at 85±2°C for 5 h. The product is precipitated with methanol, and the precipitate is vacuum dried to obtain the high molecular dispersant. The weight ratio of isooctyl acrylate, methyl methacrylate, and vinyltrimethoxysilane is 2:1:1. The total amount of azobisisobutyronitrile added is 1% of the total amount of isooctyl acrylate, methyl methacrylate, and vinyltrimethoxysilane. The amount of azobisisobutyronitrile added twice is 30% of the total amount of the first addition and the remaining amount of the second addition.

[0077] Preparation Example 3.2

[0078] The preparation method of the high molecular dispersant comprises the following steps: mixing isooctyl acrylate, toluene, and azobisisobutyronitrile, stirring and heating to 85±2°C, then adding a mixed monomer solution of methyl methacrylate and vinyltrimethoxysilane dropwise, adding azobisisobutyronitrile again after the dropwise addition is completed, and reacting at 85±2°C for 6 h. The product is precipitated with methanol, and the precipitate is vacuum dried to obtain the high molecular dispersant. The weight ratio of isooctyl acrylate, methyl methacrylate, and vinyltrimethoxysilane is 2:1:1. The total amount of azobisisobutyronitrile added is 1% of the total amount of isooctyl acrylate, methyl methacrylate, and vinyltrimethoxysilane. The amount of azobisisobutyronitrile added twice is 30% of the total amount of the first addition and the remaining amount of the second addition.

[0079] Preparation Example 4

[0080] The modified method of silicone oil comprises the following steps: mixing silicone oil and water according to the weight ratio of 1:2, then adding 35% of the weight of the silicone oil of the composite emulsifier, reacting at a temperature of 45±5 DEG C for 40±5 min, and then adjusting the pH of the emulsion to 6.5 to obtain the modified silicone oil, wherein the composite emulsifier is composed of Tween 80 and AEO-9 in a weight ratio of 0.5:0.4.

[0081] Example 1

[0082] The application discloses a preparation method of an organic silicone colorant for rail transit.

[0083] S1, 45g of the modified inorganic pigment obtained in the preparation example 1.1 and 3g of the high molecular dispersant obtained in the preparation example 3.1 are added into 30g of silicone oil for stirring and mixing;

[0084] S2, the mixture obtained in the step S1 is ground at a temperature of 50 DEG C for 30min to obtain the organic silicone colorant for rail transit.

[0085] Example 2

[0086] The application discloses a preparation method of an organic silicone colorant for rail transit.

[0087] S1, 50g of the modified inorganic pigment obtained in the preparation example 1.1 and 5g of the high molecular dispersant obtained in the preparation example 3.1 are added into 39g of silicone oil for stirring and mixing;

[0088] S2, the mixture obtained in the step S1 is ground at a temperature of 55 DEG C for 25min to obtain the organic silicone colorant for rail transit.

[0089] Example 3

[0090] The application discloses a preparation method of an organic silicone colorant for rail transit.

[0091] S1, 55g of the modified inorganic pigment obtained in the preparation example 1.1 and 8g of the high molecular dispersant obtained in the preparation example 3.2 are added into 45g of silicone oil for stirring and mixing;

[0092] S2, the mixture obtained in the step S1 is ground at a temperature of 60 DEG C for 20min to obtain the organic silicone colorant for rail transit.

[0093] Example 4

[0094] The application discloses a preparation method of an organic silicone colorant for rail transit, which is different from the example 2 in that the modified inorganic pigment is the modified inorganic pigment obtained in the preparation example 1.2, and the other steps are the same as those of the example 2.

[0095] Example 5

[0096] A method for producing a silicone colorant for rail transport, which differs from Example 2 in that the modified inorganic pigment is the modified inorganic pigment obtained in Preparation Example 1.3, and is otherwise the same as Example 2.

[0097] Example 6

[0098] A method for producing a silicone colorant for rail transport, which differs from Example 4 in that the modified inorganic pigment is the modified inorganic pigment obtained in Preparation Example 1.4, and is otherwise the same as Example 4.

[0099] Example 7

[0100] A method for producing a silicone colorant for rail transport, which differs from Example 4 in that the modified inorganic pigment is the modified inorganic pigment obtained in Preparation Example 1.5, and is otherwise the same as Example 4.

[0101] Example 8

[0102] A method for producing a silicone colorant for rail transport, which differs from Example 6 in that the modified inorganic pigment is the modified inorganic pigment obtained in Preparation Example 1.6, and is otherwise the same as Example 6.

[0103] Example 9

[0104] A method for producing a silicone colorant for rail transport, which differs from Example 6 in that the modified inorganic pigment is the modified inorganic pigment obtained in Preparation Example 1.7, and is otherwise the same as Example 6.

[0105] Example 10

[0106] A method for producing a silicone colorant for rail transport, which differs from Example 6 in that the modified inorganic pigment is the modified inorganic pigment obtained in Preparation Example 1.8, and is otherwise the same as Example 6.

[0107] Example 11

[0108] A method for producing a silicone colorant for rail transport, which differs from Example 9 in that the modified inorganic pigment is the modified inorganic pigment obtained in Preparation Example 1.9, and is otherwise the same as Example 9.

[0109] Example 12

[0110] A method for producing a silicone colorant for rail transport, which differs from Example 2 in that an equal amount of a styrene-maleic anhydride copolymer is used instead of the high-molecular dispersant obtained in Preparation Example 3.1, and is otherwise the same as Example 2.

[0111] Example 13

[0112] A method for producing an organic silicone colorant for rail transport, which differs from Example 9 in that the dispersant is a mixture of the high-molecular dispersant obtained in Preparation Example 3.1 and a styrene-maleic anhydride copolymer at 1 :0.8.

[0113] Example 14

[0114] A method for producing an organic silicone colorant for rail transport, which differs from Example 9 in that the dispersant is a mixture of the high-molecular dispersant obtained in Preparation Example 3.1 and a styrene-maleic anhydride copolymer at 1 :1.2.

[0115] Example 15

[0116] A method for producing an organic silicone colorant for rail transport, which differs from Example 9 in that the dispersant is a mixture of the high-molecular dispersant obtained in Preparation Example 3.1 and a styrene-maleic anhydride copolymer at 1 :1.6.

[0117] Example 16

[0118] A method for producing an organic silicone colorant for rail transport, which differs from Example 14 in that the styrene-maleic anhydride copolymer is the styrene-maleic anhydride copolymer modified in Preparation Example 2.1, and the others are the same as in Example 14.

[0119] Example 17

[0120] A method for producing an organic silicone colorant for rail transport, which differs from Example 14 in that the styrene-maleic anhydride copolymer is the styrene-maleic anhydride copolymer modified in Preparation Example 2.2, and the others are the same as in Example 14.

[0121] Example 18

[0122] A method for producing an organic silicone colorant for rail transport, which differs from Example 14 in that the styrene-maleic anhydride copolymer is the styrene-maleic anhydride copolymer modified in Preparation Example 2.3, and the others are the same as in Example 14.

[0123] Example 19

[0124] A method for producing an organic silicone colorant for rail transport, which differs from Example 17 in that the silicone oil is the modified silicone oil obtained in Preparation Example 4, and the others are the same as in Example 17.

[0125] Comparative Example 1

[0126] A method for producing an organic silicone colorant for rail transport, which differs from Example 2 in that the inorganic pigment is an inorganic pigment that has not been modified, and the others are the same as in Example 2.

[0127] Comparative Example 2

[0128] A method for preparing a silicone colorant for rail transit, which is different from Example 2 in that the modified inorganic pigment is the modified inorganic pigment obtained in Comparative Preparation Example 1.1, and the others are the same as Example 2.

[0129] Comparative Example 3

[0130] A method for preparing a silicone colorant for rail transit, which is different from Example 2 in that the modified inorganic pigment is the modified inorganic pigment obtained in Comparative Preparation Example 1.2, and the others are the same as Example 2.

[0131] Comparative Example 4

[0132] A method for preparing a silicone colorant for rail transit, which is different from Example 2 in that the modified inorganic pigment is the modified inorganic pigment obtained in Comparative Preparation Example 1.3, and the others are the same as Example 2.

[0133] Comparative Example 5

[0134] A method for preparing a silicone colorant for rail transit, which is different from Example 2 in that the modified inorganic pigment is the modified inorganic pigment obtained in Comparative Preparation Example 1.4, and the others are the same as Example 2.

[0135] Performance detection

[0136] The silicone colorants obtained in the above examples and comparative examples were tested for dispersion performance, thermal stability, and insulation performance, and the test results are shown in Table 1.

[0137] The dispersion performance test was performed by taking a small amount of the above obtained colorant into a transparent glass cup and observing the suspension state. If the suspension state is stable, the color is uniform, and there is no any precipitation or color spot, it indicates that the dispersion performance of the colorant is good.

[0138] The thermal stability test was performed by adding 1 g of silicone colorant into 100 g of silicone rubber, vulcanizing / curing, and then placing it in an oven at 250°C for 6h. After cooling, the color difference was detected by a color difference meter, where ΔE (comprehensive color difference) = (ΔL 2 +Δa 2 +Δb 2 ) 1 / 2 .

[0139] Table 1 Performance test results of silicone colorants

[0140]

[0141]

[0142] From the above table, it can be seen that:

[0143] The organic silicone colorants obtained in Examples 1-3 have good dispersion performance and insulation performance, and the comprehensive color difference value ΔE is ≤1.30, indicating that the organic silicone colorants obtained in the present application have certain heat resistance.

[0144] Compared with Example 2, the modified inorganic pigments in Examples 4-5 are prepared by using the modified inorganic pigments obtained in Preparation Examples 1.2-1.3, and after adjusting the ratio of the sepiolite powder and 3-aminopropyltrimethoxysilane in the modified inorganic pigments, the fineness of the organic silicone colorants obtained in Examples 4-5 is reduced compared with that of Example 2, indicating that the dispersion performance of the organic silicone colorants obtained in Examples 4-5 is better than that of the organic silicone colorants obtained in Example 2, and the comprehensive color difference value of the organic silicone colorants obtained in Examples 4-5 is further reduced, indicating that after adjusting the ratio of the sepiolite powder and 3-aminopropyltrimethoxysilane, the heat resistance of the organic silicone colorants is further improved.

[0145] Compared with Example 2, the modified inorganic pigments in Examples 6-7 are prepared by using the modified inorganic pigments obtained in Preparation Examples 1.4-1.5, and the comprehensive color difference value ΔE of the organic silicone colorants obtained in Examples 6-7 is reduced compared with that of Example 2, and is also lower than that of the organic silicone colorants in Example 4, indicating that the reaction temperature of the inorganic pigments, sepiolite powder and 3-aminopropyltrimethoxysilane has a certain influence on the heat resistance of the organic silicone colorants.

[0146] Compared with Example 6, the sepiolite powder in the preparation of the modified inorganic pigments in Examples 8-10 is modified sepiolite powder, and the fineness of the organic silicone colorants obtained in Examples 8-10 is further reduced, and the comprehensive color difference value ΔE is further reduced, indicating that after the sepiolite powder is modified, the dispersion performance of the inorganic pigments and the heat resistance of the final colorant can be further improved.

[0147] In Examples 13-15, when the dispersant is a mixture of the high molecular dispersant obtained in Preparation Example 3.1 and the styrene-maleic acid copolymer, the dispersion performance of the high molecular dispersant obtained in Preparation Example 3.1 in Examples 13-15 is further improved compared with the use of the high molecular dispersant obtained in Preparation Example 3.1 or the styrene-maleic anhydride copolymer alone, the comprehensive color difference value is reduced, and the heat resistance is also improved.

[0148] Compared with Example 14, when the styrene-maleic anhydride copolymer is further esterified, the dispersion performance and heat resistance of the organic silicone colorants obtained in Examples 16-18 are further improved compared with those of Example 14.

[0149] Compared with Example 17, the fineness of the pigment is further reduced when the silicone oil is replaced by the modified silicone oil, which indicates that the compatibility between the modified silicone oil and the dispersant and the sepiolite powder is better, the dispersion performance of the pigment in the silicone oil is improved, and the comprehensive color difference value of the colorant is smaller and the coloring ability is stronger due to the good dispersion of the pigment in the silicone oil.

[0150] Compared with Example 2, the dispersion performance of the silicone colorant obtained in Comparative Example 1 is poor, the comprehensive color difference value is high, and the heat resistance is poor, which indicates that the dispersion performance of the inorganic pigment in the silicone oil is effectively improved after the modification of the inorganic pigment, so that the dispersion performance and the heat resistance of the silicone colorant are improved.

[0151] Compared with Example 2, the performance of the silicone colorant obtained in Comparative Examples 2-5 is reduced when the modified inorganic pigment is replaced by the modified inorganic pigment obtained in Comparative Preparation Examples 1.1-1.4, which indicates that the use of the components in the application can effectively ensure that the silicone colorant has good dispersion performance, heat resistance and insulation performance.

[0152] The examples in the specific embodiment are the preferred examples of the application, but do not limit the protection scope of the application, so that: any equivalent changes made according to the structure, shape, principle of the application should be covered within the protection scope of the application.

Claims

1. A silicone colorant for rail transportation, characterized by: The organic silicone colorant comprises the following raw materials by weight: modified inorganic pigment 45-55 parts, silicone oil 30-45 parts, dispersant 3-8 parts; the modified inorganic pigment is obtained by the following modification method: ultrasonic dispersion of inorganic pigment in water, then adding sepiolite powder under the condition of temperature 40-50℃ ultrasonic dispersion for 50-60min, then adding amino silane coupling agent to form a suspension after ultrasonic dispersion, then reacting under the condition of temperature 70-100℃ for 0.5-1.5h, after the reaction is completed, centrifugation, washing, drying, grinding through 200 mesh sieve to obtain modified inorganic pigment; the dispersant is composed of high molecular dispersant and styrene-maleic anhydride copolymer with weight ratio of 1: (0.8-1.6); the high molecular dispersant is obtained by the following preparation method: mixing isooctyl acrylate, toluene, azobisisobutyronitrile, stirring and heating to 85±2℃, then dropping the mixed monomer solution of methyl methacrylate and vinyl trimethoxysilane, after dropping is completed, adding azobisisobutyronitrile, keeping the temperature at 85±2℃ for 5-6h, then precipitating with methanol, vacuum drying the precipitate to obtain high molecular dispersant.

2. The silicone colorant for rail transportation according to claim 1, characterized by: The weight ratio of the inorganic pigment, sepiolite powder and amino silane coupling agent is 1: (0.4-0.7): (0.05-0.2).

3. The silicone colorant for rail transportation according to claim 1 or 2, characterized by: The amino silane coupling agent is one of 3-aminopropyl trimethoxysilane and 3-aminopropyl triethoxysilane.

4. A silicone colorant for rail transportation, characterized by: The organic silicone colorant comprises the following raw materials by weight: modified inorganic pigment 45-55 parts, silicone oil 30-45 parts, dispersant 3-8 parts; the modified inorganic pigment is obtained by the following modification method: ultrasonic dispersion of inorganic pigment in water, then adding modified sepiolite powder under the condition of temperature 40-50℃ ultrasonic dispersion for 50-60min, then adding amino silane coupling agent to form a suspension after ultrasonic dispersion, then reacting under the condition of temperature 70-100℃ for 0.5-1.5h, after the reaction is completed, centrifugation, washing, drying, grinding through 200 mesh sieve to obtain modified inorganic pigment; the dispersant is composed of high molecular dispersant and styrene-maleic anhydride copolymer with weight ratio of 1: (0.8-1.6); the high molecular dispersant is obtained by the following preparation method: mixing isooctyl acrylate, toluene, azobisisobutyronitrile, stirring and heating to 85±2℃, then dropping the mixed monomer solution of methyl methacrylate and vinyl trimethoxysilane, after dropping is completed, adding azobisisobutyronitrile, keeping the temperature at 85±2℃ for 5-6h, then precipitating with methanol, vacuum drying the precipitate to obtain high molecular dispersant, the modified sepiolite powder is obtained by the following modification method: adding sepiolite powder into hydrochloric acid with concentration of 1.8-3.2mol / L, stirring for 5-6h, then washing with water until neutral and chloride content is less than 0.001%, then drying at 80-90℃ after centrifugal separation, grinding through 200 mesh sieve to obtain modified sepiolite powder, the ratio of sepiolite powder to hydrochloric acid is 1g: (7-10)mL.

5. A silicone colorant for rail transportation, characterized by: The organic silicone colorant comprises the following raw materials by weight: modified inorganic pigment 45-55 parts, modified silicone oil 30-45 parts, dispersant 3-8 parts; the modified inorganic pigment is obtained by the following modification method: ultrasonic dispersion of inorganic pigment in water, then adding sepiolite powder and ultrasonic dispersion for 50-60 min at a temperature of 40-50℃, then adding amino silane coupling agent to form a suspension after ultrasonic dispersion, and then reacting at a temperature of 70-100℃ for 0.5-1.5h, centrifugation, washing, drying, and grinding to 200 mesh after the reaction is completed; the dispersant is composed of a high molecular dispersant and a styrene-maleic anhydride copolymer at a weight ratio of 1: (0.8-1.6); the high molecular dispersant is obtained by the following preparation method: mixing isooctyl acrylate, toluene, and azobisisobutyronitrile, stirring and heating to 85±2℃, then adding a mixed monomer solution of methyl methacrylate and vinyltrimethoxysilane dropwise, adding azobisisobutyronitrile after the dropwise addition is completed, reacting for 5-6h at a temperature of 85±2℃, and then precipitating with methanol, vacuum drying the precipitate to obtain the high molecular dispersant; the modified silicone oil is obtained by the following modification method: mixing silicone oil and water at a weight ratio of 1:2, then adding a composite emulsifier at 35% of the weight of the silicone oil, reacting for 40±5min at a temperature of 45±5℃, and then adjusting the pH of the emulsion to 6.5 to obtain the modified silicone oil, wherein the composite emulsifier is composed of Tween 80 and AEO-9 at a weight ratio of 0.5:0.

4.

6. A silicone colorant for rail transportation, characterized by: The organic silicone colorant comprises raw materials in the following weight parts: modified inorganic pigment 45-55 parts, silicone oil 30-45 parts, dispersant 3-8 parts; the modified inorganic pigment is obtained by the following modification method: ultrasonic dispersion of inorganic pigment in water, then addition of sepiolite powder and ultrasonic dispersion for 50-60 min at a temperature of 40-50℃, then addition of amino silane coupling agent to form a suspension and reaction for 0.5-1.5 h at a temperature of 70-100℃, centrifugation, washing, drying, grinding and passing through a 200-mesh screen after reaction completion to obtain the modified inorganic pigment; the dispersant is composed of a high-molecular dispersant and a modified styrene-maleic anhydride copolymer in a weight ratio of 1:(0.8-1.6); the high-molecular dispersant is obtained by the following preparation method: mixing isooctyl acrylate, toluene and azobisisobutyronitrile, stirring and heating to 85±2℃, then dropwise addition of a mixed monomer solution of methyl methacrylate and vinyltrimethoxysilane, dropwise addition completion, addition of azobisisobutyronitrile, reaction for 5-6 h at a temperature of 85±2℃, then methanol precipitation, vacuum drying of the precipitate to obtain the high-molecular dispersant; the modified styrene-maleic anhydride copolymer is obtained by the following modification method: mixing toluene, a catalyst, a styrene-maleic anhydride copolymer and isobutanol under nitrogen atmosphere protection, constant-temperature reaction for 5-6 h at 80±5℃, reaction end, removal of toluene by rotary evaporation, then precipitation of the product in petroleum ether to obtain a precipitate, vacuum drying of the precipitate at 30℃ to obtain the modified styrene-maleic anhydride copolymer, and the mass ratio of the styrene-maleic anhydride copolymer to isobutanol is 1:(2-2.5).

7. The silicone colorant for rail transportation according to claim 6, characterized by: The catalyst is p-toluenesulfonic acid.

8. The silicone colorant for rail transportation according to claim 1, characterized by: The weight ratio of isooctyl acrylate, methyl methacrylate and vinyltrimethoxysilane is 2:1:

1.

9. A method for producing a silicone colorant for rail transport according to any one of claims 1 to 3, characterized by: The method comprises the following steps: S1, mixing and stirring of the modified inorganic pigment and the dispersant in the silicone oil; S2, grinding of the mixture obtained in step S1 at a temperature of 50-60℃ for 20-30 min to obtain the organic silicone colorant for rail transit.

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