Preparation method of pre-modified precipitated white carbon black based on surface organification
By adding premodifying agent RY in the pulping process of white carbon black and spray-drying, preorganized modified white carbon black was prepared, which solved the problem of VOC emissions during the in-situ modification of white carbon black, and achieved better dispersion effect and performance optimization of white carbon black in rubber composite materials.
Patent Information
- Application Number
- CN202411645272.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-18
- Publication Date
- 2025-02-25
AI Technical Summary
In situ modification of white carbon black, existing coupling agents will emit a large amount of volatile organic compounds (VOCs), resulting in environmental pollution.
The pre-modified precipitated white carbon black is prepared by preparing the pre-modified precipitated white carbon black by preparing the pre-modified agent RY and adding it during the pulping process of the white carbon black, followed by spray drying to obtain the pre-organized modified white carbon black.
This method can reduce the energy consumption of white carbon black in the rubber matrix, improve the dispersion effect of white carbon black in rubber composite materials, optimize the traditional white carbon black rubber mixing and processing technology, and provide an industrial production solution for white carbon black/rubber composite materials with excellent performance.
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Figure CN119505575A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of silicone rubber materials, in particular to a preparation method of surface organic pre-modified precipitated silica. Background Art
[0002] At present, there are two main ways to modify silica: physical modification and chemical modification. The physical modification of silica is mainly based on physical adsorption to reduce or eliminate the large number of hydroxyl groups coated on the surface of silica; chemical modification of silica is currently widely used.
[0003] By means of chemical reaction, the active hydroxyl groups on the surface of silica will react to graft chain segments onto its surface. While shielding the number of hydroxyl groups, the organic chain segments can use the functional groups at the other end to achieve the function of connecting silica and rubber molecules. The main means at present are hydroxyl condensation reaction and epoxy ring opening, both of which belong to in-situ modification. In the silicone rubber production process, in the in-situ modification blending method, the side reactions in the process of in-situ modification of silica by coupling agents will emit a large amount of typical volatile organic compounds (VOCs) such as methanol or ethanol, causing environmental pollution problems.
[0004] Based on this, the present invention designs a preparation method based on surface organic pre-modified precipitated silica to solve the above problems. Summary of the invention
[0005] The purpose of the present invention is to provide a preparation method of precipitated silica based on surface organic pre-modification, so as to solve the problem that the side reaction in the process of in-situ modification of silica by coupling agents mentioned in the above background technology will emit a large amount of typical volatile organic compounds (VOCs) such as methanol or ethanol, causing environmental pollution.
[0006] To achieve the above-mentioned purpose, the present invention provides the following technical scheme: a preparation method of surface organic pre-modified precipitated silica, comprising the following steps: preparing a pre-modifier RY; adding the pre-modifier RY during silica pulping to obtain a modifier / silica slurry; spray drying the modifier / silica slurry to obtain pre-organized modified silica.
[0007] Furthermore, in the process of preparing silica pulp, the pre-modifier RY is added to obtain a modifier / silica slurry, including: weighing a certain mass of precipitated silica powder, dispersing it in water, and mechanically stirring to obtain a silica suspension; mixing the pre-modifier RY into the silica suspension, grinding it with a colloid mill, and obtaining the modifier / silica slurry.
[0008] Furthermore, after dispersing the white carbon black powder in water, the method further includes: controlling the solid content of the solution to be less than 10%.
[0009] Furthermore, the grinding time of the colloid mill is 20 to 30 minutes, and the amount of the pre-modifier RY is 10% of the mass of the white carbon black.
[0010] Furthermore, in the process of preparing silica pulp, the pre-modifier RY is added to obtain a modifier / silica slurry, including: weighing a certain mass of precipitated silica powder, dispersing it in water, and mechanically stirring to obtain a silica suspension; grinding the silica suspension with a colloid mill to obtain a silica slurry; mixing the pre-modifier RY into the silica slurry and stirring to obtain the modifier / silica slurry.
[0011] Furthermore, after dispersing the white carbon black powder in water, the method further includes: controlling the solid content of the solution to be less than 10%.
[0012] Furthermore, the grinding time of the colloid mill is 20 to 30 minutes, the amount of the pre-modifier RY is 8% to 12% of the dry weight of the white carbon black slurry, and the stirring and mixing time is greater than 1 hour.
[0013] Furthermore, the pre-modifier RY is prepared, including: mixing n-butanol and bis-(γ-triethoxysilylpropyl) tetrasulfide (Si-69) to obtain a mixture; adding the mixture into water and stirring until it is completely dissolved to obtain the pre-modifier RY.
[0014] Furthermore, the mass ratio of the n-butanol to the bis-(γ-triethoxysilylpropyl) tetrasulfide (Si-69) is 1:2.
[0015] Furthermore, the modifier / silica slurry is spray-dried to obtain pre-organized modified silica, including: spray-drying the modifier / silica slurry through a spray dryer; controlling the outlet temperature of the spray dryer to be 120-140° C. to obtain the pre-organized modified silica.
[0016] One or more technical solutions provided in the embodiments of the present invention have at least the following technical effects or advantages: by adding a pre-modifier RY during the pulping and grinding stage or during the pulping process to obtain a slurry. After adding the pre-modifier RY, the pre-organized modified white carbon black can be obtained by spray drying. The method is simple. Before the white carbon black is filled into the rubber matrix, the surface-organized modified white carbon black is prepared, which can reduce its mixing energy consumption in the rubber matrix and improve the dispersion effect of the white carbon black in the rubber composite material, thereby optimizing the traditional white carbon black rubber mixing process and providing convenience for the large-scale industrial production of white carbon black / rubber composite materials with excellent performance. Moreover, compared with the white carbon black produced by the ordinary conventional method, the prepared white carbon black is more evenly dispersed in the rubber matrix, the overall viscosity is reduced, the modulus of elongation is improved, and the reinforcement effect on the rubber is more ideal. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for describing the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.
[0018] Figure 1 The present invention is a schematic flow diagram of the method for preparing pre-modified precipitated silica. DETAILED DESCRIPTION
[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0020] like Figure 1 As shown, a preparation method based on surface organic pre-modified precipitated silica comprises the following steps:
[0021] Step S10: preparing a preliminary modifier RY.
[0022] Step S20: During the white carbon black pulping process, the pre-modifier RY is added to obtain a modifier / white carbon black water slurry.
[0023] Step S30: spray-drying the modifier / white carbon black slurry to obtain pre-organized white carbon black.
[0024] It is not difficult to find out through the above steps that in the process of preparing pre-modified precipitated silica, the pre-modifier RY is prepared in advance. And in the pulping process before spray drying, it can be the pulping grinding stage or the pulping process to obtain the slurry, the pre-modifier RY is added. After adding the pre-modifier RY, the pre-organized silica can be obtained by spray drying. Furthermore, it can be achieved that before the silica is filled into the rubber matrix, the surface organic modified silica can be prepared to reduce its mixing energy consumption in the rubber matrix, improve the dispersion effect of silica in the rubber composite material, thereby optimizing the traditional silica rubber mixing process, and providing convenience for the large-scale industrial production of silica / rubber composite materials with excellent performance.
[0025] In step S10, a pre-modifying agent RY is prepared, including:
[0026] Step S101: mixing n-butanol and bis-(γ-triethoxysilylpropyl) tetrasulfide (Si-69) to obtain a mixture;
[0027] Step S102: adding the mixture into water and stirring until it is completely dissolved to obtain the pre-modifier RY.
[0028] In this embodiment, in preparing the pre-modifier RY, n-butanol and bis-(γ-triethoxysilylpropyl) tetrasulfide (Si-69) are first mixed, and then water is added to stir and dissolve, thereby obtaining the pre-modifier RY.
[0029] Preferably, the mass ratio of the n-butanol to the bis-(γ-triethoxysilylpropyl) tetrasulfide (Si-69) is 1: 2. Under this ratio, the use effect of the pre-modifier RY is better.
[0030] In step S20, during the white carbon black pulping process, the pre-modifier RY is added to obtain a modifier / white carbon black water slurry, comprising:
[0031] Step S201a: Weigh a certain mass of precipitated silica powder, disperse it in water, and mechanically stir to obtain a silica suspension;
[0032] Step S202a: mixing the pre-modifier RY into the silica suspension, grinding with a colloid mill, and obtaining the modifier / silica slurry.
[0033] In this embodiment, in the process of preparing the modifier / white carbon black slurry, the white carbon black powder can be used to obtain micron-sized white carbon black by a precipitation method. The micron-sized white carbon black is added to water for dispersion and stirring to obtain a white carbon black suspension. Furthermore, the pre-modifier RY can be added before grinding after the white carbon black suspension is obtained, thereby realizing the addition of the pre-modifier RY during the grinding process of preparing the modifier / white carbon black slurry. Specifically, the pre-modifier RY and the white carbon black suspension can be ground after mixing by a colloid mill. Among them, the colloid mill is a processing equipment made of materials such as stainless steel. It relies on the combined action of the self-gravity and centrifugal force of the processed material to achieve a crushing effect through shearing and friction.
[0034] Furthermore, after dispersing the white carbon black powder in water, the method further comprises: controlling the solid content of the solution to be less than 10%.
[0035] Furthermore, the grinding time of the colloid mill is 20 to 30 minutes, and the amount of the pre-modifier RY is 10% of the mass of the white carbon black.
[0036] In step S20, during the white carbon black pulping process, the pre-modifier RY is added to obtain a modifier / white carbon black water slurry, comprising:
[0037] Step S201b: Weigh a certain mass of precipitated silica powder, disperse it in water, and mechanically stir to obtain a silica suspension;
[0038] Step S202b: grinding the white carbon black suspension using a colloid mill to obtain white carbon black slurry;
[0039] Step S203b: mixing the pre-modifier RY into the silica slurry and stirring to obtain the modifier / silica slurry.
[0040] In this embodiment, in the process of preparing the modifier / white carbon black slurry, the white carbon black powder can be used to obtain micron-sized white carbon black by a precipitation method. The micron-sized white carbon black is added to water for dispersion and stirring to obtain a white carbon black suspension. Furthermore, the white carbon black suspension can be ground after being obtained to obtain a white carbon black slurry. After obtaining the white carbon black slurry, the pre-modifier RY is added, so that after the white carbon black slurry is prepared, the pre-modifier RY is added, and after the pre-modifier RY is added, the modifier / white carbon black slurry is obtained by stirring and mixing. Specifically, the pre-modifier RY and the white carbon black suspension can be ground after being mixed by a colloid mill. Among them, the colloid mill is a processing equipment made of materials such as stainless steel. It relies on the combined action of the self-gravity and centrifugal force of the processed material to achieve a crushing effect through shearing and friction.
[0041] Furthermore, after dispersing the white carbon black powder in water, the method further comprises: controlling the solid content of the solution to be less than 10%.
[0042] Furthermore, the grinding time of the colloid mill is 20 to 30 minutes, the amount of the pre-modifier RY is 8% to 12% of the dry weight of the white carbon black slurry, and the stirring and mixing time is greater than 1 hour.
[0043] In step S30, the modifier / white carbon black slurry is spray-dried to obtain pre-organized white carbon black, comprising:
[0044] Step S301: spray drying the modifier / white carbon black slurry through a spray dryer;
[0045] Step S302: controlling the outlet temperature of the spray drying to 120-140° C. to obtain the pre-organized modified white carbon black.
[0046] The invention provides a preparation method based on surface organic pre-modified precipitated white carbon black. Compared with white carbon black produced by ordinary conventional methods, the prepared white carbon black has more uniform dispersion in the rubber matrix, lower overall viscosity, and higher modulus of elongation; and has a more ideal reinforcement effect on rubber.
[0047] Example 1
[0048] The present invention provides a preparation process of surface organic pre-modified precipitated silica, which specifically comprises the following steps:
[0049] Step 1: prepare a pre-modifier RY, that is, n-butanol and bis-(γ-triethoxysilylpropyl) tetrasulfide (Si-69) are mixed in a mass ratio of 1:2, added into water and stirred until completely dissolved.
[0050] Step 2: Weigh a certain mass of precipitated silica powder, disperse it in water, control the solid content of the solution to be within 10%, and mechanically stir it into a uniform silica suspension.
[0051] Step 3: Mix the pre-modifier RY into the silica suspension and grind it with a colloid mill for 20-30 minutes to obtain a relatively viscous modifier / silica slurry. The amount of the pre-modifier RY is 10% of the mass of silica.
[0052] Step 4: Dry the above modifier / white carbon black slurry with a spray dryer at an outlet temperature of 120-140° C. to obtain pre-organized modified white carbon black.
[0053] Example 2
[0054] The present invention provides a preparation process of surface organic pre-modified precipitated silica, which specifically comprises the following steps:
[0055] Step 1: prepare a pre-modifier RY, that is, n-butanol and bis-(γ-triethoxysilylpropyl) tetrasulfide (Si-69) are mixed in a mass ratio of 1:2, added into water and stirred until completely dissolved.
[0056] Step 2: In the preparation or production process of precipitated silica, specifically in the pulping process before spray drying, add a pre-modifier RY to the pulp in an amount of (8-12)% of the dry weight of the pulp, stir evenly for 1 hour, spray dry, and dry at an outlet temperature of 120-140°C to obtain pre-organized modified silica.
[0057] According to the national chemical industry standard HG / T2404-2020 "Rubber Compounding Agent-Identification of Precipitated Hydrated Silica in Styrene-Butadiene Rubber", the test results of the application performance of the pre-modified precipitated silica prepared in the above embodiments are shown in Table 1.
[0058] Table 1: Test results of application performance of pre-modified precipitated silica prepared in Example 1 and Example 2
[0059]
[0060] It can be seen from Table 1 that the hardness, 300% tensile force, tensile strength, tear force, elongation, abrasion (DIN autobiography) (10N×30×84), elasticity, density, 500% tensile force, tensile value and Akron of the pre-modified precipitated silica prepared in Example 1 and Example 2 all meet the reference value requirements.
[0061] In summary, the present invention discloses a preparation method based on surface organic pre-modified precipitated white carbon black, by adding a pre-modifier RY in the pulping and grinding stage or in the pulping process to obtain a slurry. After adding the pre-modifier RY, the pre-organized white carbon black can be obtained by spray drying. The method is simple. Before the white carbon black is filled into the rubber matrix, the surface organic modified white carbon black is prepared, which can reduce its mixing energy consumption in the rubber matrix and improve the dispersion effect of the white carbon black in the rubber composite material, thereby optimizing the traditional white carbon black rubber mixing process and providing convenience for the large-scale industrial production of white carbon black / rubber composite materials with excellent performance. Moreover, compared with the white carbon black produced by the ordinary conventional method, the prepared white carbon black is more evenly dispersed in the rubber matrix, the overall viscosity is reduced, the modulus of elongation is increased, and the reinforcement effect on the rubber is more ideal. Therefore, the present invention effectively overcomes the various shortcomings in the prior art and has a high industrial utilization value.
[0062] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.
[0063] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.
Claims
1. A method for preparing surface organic pre-modified precipitated silica, characterized in that: The steps include: Prepare the pre-modifier RY; In the process of preparing silica pulp, the pre-modifier RY is added to obtain a modifier / silica pulp. The modifier / white carbon black water slurry is spray-dried to obtain pre-organized modified white carbon black.
2. The method for preparing surface organic pre-modified precipitated silica according to claim 1, characterized in that: In the process of preparing white carbon black pulp, the pre-modifier RY is added to obtain a modifier / white carbon black water slurry, comprising: Weigh a certain mass of precipitated silica powder, disperse it in water, and mechanically stir to obtain a silica suspension; The pre-modifier RY is mixed into the silica suspension and ground using a colloid mill to obtain the modifier / silica slurry.
3. The method for preparing surface organic pre-modified precipitated silica according to claim 2, characterized in that: After dispersing the white carbon black powder in water, the method further includes: controlling the solid content of the solution to be less than 10%.
4. The method for preparing surface organic pre-modified precipitated silica according to claim 2, characterized in that: The grinding time of the colloid mill is 20 to 30 minutes, and the amount of the pre-modifier RY is 10% of the mass of the white carbon black.
5. The method for preparing surface organic pre-modified precipitated silica according to claim 1, characterized in that: In the process of preparing white carbon black pulp, the pre-modifier RY is added to obtain a modifier / white carbon black water slurry, comprising: Weigh a certain mass of precipitated silica powder, disperse it in water, and mechanically stir to obtain a silica suspension; Grinding the white carbon black suspension using a colloid mill to obtain a white carbon black slurry; The pre-modifier RY is mixed into the white carbon black slurry and stirred to obtain the modifier / white carbon black water slurry.
6. The method for preparing surface organic pre-modified precipitated silica according to claim 5, characterized in that: After dispersing the white carbon black powder in water, the method further includes: controlling the solid content of the solution to be less than 10%.
7. The method for preparing surface organic pre-modified precipitated silica according to claim 5, characterized in that: The grinding time of the colloid mill is 20 to 30 minutes, the amount of the pre-modifier RY is 8% to 12% of the dry weight of the white carbon black slurry, and the stirring and mixing time is greater than 1 hour.
8. A method for preparing surface organic pre-modified precipitated silica according to any one of claims 1 to 7, characterized in that: The pre-modifier RY is prepared, including: mixing n-butanol and bis-(γ-triethoxysilylpropyl)tetrasulfide (Si-69) to obtain a mixture; The mixture was added into water and stirred until completely dissolved to obtain the pre-modifier RY.
9. The method for preparing surface organic pre-modified precipitated silica according to claim 8, characterized in that: The mass ratio of n-butanol to bis-(γ-triethoxysilylpropyl) tetrasulfide (Si-69) is 1:
2.
10. The method for preparing surface organic pre-modified precipitated silica according to claim 1, characterized in that: The modifier / white carbon black slurry is spray-dried to obtain pre-organized white carbon black, comprising: The modifier / white carbon black slurry is spray-dried by a spray dryer; The outlet temperature of the spray drying is controlled to be 120-140° C. to obtain the pre-organized modified white carbon black.