阅读说明：本技术 一种含有改性白炭黑的胶辊用硅橡胶及其制备方法 (Silicon rubber for rubber covered roller containing modified white carbon black and preparation method thereof ) 是由 林林浩 黄冰林 于 2020-07-10 设计创作，主要内容包括：本发明涉及有机硅的技术领域,具体公开了一种改性白炭黑,改性白炭黑包括粉煤灰10份-16份；碳酸钠28份-45份；对甲苯磺酸31份-48份；二甲基二甲氧基硅烷1.3份-2.4份；正辛醇52份-81份；乙醇24份-36份；水58份-74份；其制备方法为：将粉煤灰与碳酸钠反应,随后加对甲苯磺酸酸浸；加入二甲基二甲氧基硅烷和正辛醇改性,即得改性白炭黑。还公开了一种含有改性白炭黑的胶辊用硅橡胶,包括甲基乙烯基硅橡胶100份；改性白炭黑10份-90份；其制备方法为：将甲基乙烯基硅橡胶和改性白炭黑加入捏合机混合成团。本发明生产的硅橡胶不添加结构控制剂,可以显著提高回弹性和加工性能。(The invention relates to the technical field of organosilicon, and particularly discloses modified white carbon black, which comprises 10-16 parts of fly ash; 28-45 parts of sodium carbonate; 31-48 parts of p-toluenesulfonic acid; 1.3 to 2.4 portions of dimethyl dimethoxy silane; 52-81 parts of n-octanol; 24-36 parts of ethanol; 58-74 parts of water; the preparation method comprises the following steps: reacting fly ash with sodium carbonate, and adding p-toluenesulfonic acid for acid leaching; adding dimethyl dimethoxy silane and n-octanol for modification to obtain modified white carbon black. Also discloses silicon rubber for the rubber roller containing the modified white carbon black, which comprises 100 parts of methyl vinyl silicone rubber; 10-90 parts of modified white carbon black; the preparation method comprises the following steps: adding the methyl vinyl silicone rubber and the modified white carbon black into a kneader to be mixed into a mass. The silicone rubber produced by the invention does not add a structure control agent, and can obviously improve resilience and processability.)

1. The modified white carbon black is characterized by being prepared from the following raw materials in parts by weight:

fly ash: 10-16 parts;

sodium carbonate: 28-45 parts;

p-toluenesulfonic acid: 31-48 parts;

dimethyl dimethoxy silane: 1.3-2.4 parts;

n-octanol: 52-81 parts;

ethanol: 24-36 parts;

water: 58-74 parts;

wherein the mesh number of the fly ash is 90-120 meshes.

2. The preparation method of the modified white carbon black is based on the modified white carbon black of claim 1, and is characterized by comprising the following preparation steps:

s1, uniformly mixing the fly ash and sodium carbonate, melting at 1300-1600 ℃ for 1-1.5 h, adding 80% of water by mass fraction, extracting, leaching, filtering and concentrating to obtain a semi-finished product of white carbon black;

s2, adding 20% by mass of white carbon black semi-finished product into water for dissolving, adding p-toluenesulfonic acid for acid leaching for 5-9 h, controlling the system temperature at 28-35 ℃, then heating to 50-80 ℃, adjusting the PH value to 5-7, and curing for 20-30 min to obtain a suspension;

and S3, adding dimethyl dimethoxy silane and ethanol into the suspension, performing ultrasonic dispersion for 20min-30min, heating to 100-120 ℃, stirring for reaction for 8-12 h, adding n-octanol, performing reflux water diversion for 4-5 h, cooling, filtering, washing and drying to obtain the modified white carbon black.

3. The preparation method of the modified white carbon black based on the silicon rubber for the rubber roller containing the modified white carbon black of claim 2 is characterized in that the silicon rubber for the rubber roller is prepared from the following raw materials in parts by weight:

methyl vinyl silicone rubber: 100 parts of (A);

modified white carbon black: 10-90 parts;

wherein the molar mass of the raw methyl vinyl silicone rubber is 30W-60W, and the mass percentage of vinyl in the methyl vinyl silicone rubber is 0.03% -5%.

4. The silicone rubber for rubber covered rollers containing modified white carbon black according to claim 3, wherein the silicone rubber further comprises a release agent in an amount of 0.01 to 0.5 parts by weight.

5. The silicone rubber for rubber covered rollers containing modified white carbon black according to claim 4, wherein the release agent is zinc stearate.

6. The silicone rubber for rubber covered rollers containing modified white carbon black according to claim 3, wherein the silicone rubber further comprises a heat-resistant agent in an amount of 0.5 to 5 parts by weight.

7. The silicone rubber for rubber covered rollers containing modified white carbon black according to claim 6, wherein the heat-resistant agent is prepared from nano iron oxide, nano titanium oxide and nano cerium oxide in a mass ratio of 2:1:3, and mixing the components in a ratio of 3.

8. The silicone rubber for rubber covered rolls containing modified white carbon black according to claim 3, wherein the silicone rubber further comprises triethanolamine borate, and the weight part of the triethanolamine borate is 0.7-1.4 parts.

9. The preparation method of the silicon rubber for the rubber roller containing the modified white carbon black is based on any one of claims 3 to 8, and is characterized by comprising the following steps of:

s1, adding the methyl vinyl silicone rubber and the modified white carbon black into a kneader, controlling the system temperature at 80-100 ℃, and mixing into a mass;

s2, putting the product into an oven for vulcanization, controlling the temperature of the system to rise to 140-160 ℃, and carrying out heat treatment for 1-3 h to obtain a mixed glue solution;

and S3, after the step S2 is finished, injecting the mixed glue solution into a mold for molding, and obtaining the silicone rubber.

10. The method for preparing the silicone rubber for the rubber covered roller containing the modified white carbon black according to claim 9, wherein a release agent, a heat-resistant agent and triethanolamine borate are further added in the step of S1.

Technical Field

The invention relates to the technical field of organic silicon, in particular to silicon rubber for rubber rollers containing modified white carbon black and a preparation method thereof.

Background

The silicon rubber is widely applied in the rubber roller industry, and the structural control agent is mainly hydroxyl, methoxy and ethoxy silicon oil or diphenyl silanediol and the like, has the functions of shortening the kneading molding time, treating the hydroxyl in the filler white carbon black, prolonging the storage time of the silicon rubber, improving the processability of the silicon rubber and avoiding the occurrence of the structurization of the rubber material, and is an essential component in the silicon rubber formula.

Disclosure of Invention

Aiming at the problems of insufficient rebound resilience and operability in the prior art, the first object of the invention is to provide modified white carbon black, and the silicone rubber produced by using the modified white carbon black has the advantages of high rebound resilience and operability.

The second purpose of the invention is to provide a preparation method of modified white carbon black, and the preparation method has the advantages of saving resources and reducing cost.

The third purpose of the invention is to provide the silicone rubber for the rubber roller containing the modified white carbon black, wherein the silicone rubber does not need to be added with a structural control agent, and the resilience and the processing performance of the silicone rubber are improved.

The fourth purpose of the invention is to provide a preparation method of the silicon rubber for the rubber roller containing the modified white carbon black, and the preparation method has the advantage of simple steps.

In order to achieve the first object, the invention provides the following technical scheme:

the modified white carbon black is prepared from the following raw materials in parts by weight:

fly ash: 10-16 parts;

sodium carbonate: 28-45 parts;

p-toluenesulfonic acid: 31-48 parts;

dimethyl dimethoxy silane: 1.3-2.4 parts;

n-octanol: 52-81 parts;

ethanol: 24-36 parts;

water: 58-74 parts;

wherein the mesh number of the fly ash is 90-120 meshes.

By adopting the technical scheme, because a large amount of hydrophilic hydroxyl groups exist on the surface of the white carbon black and are difficult to disperse in an organic phase, the modified white carbon black has hydrophobic and oleophilic properties by utilizing the combination of the hydroxyl groups on the surfaces of the dimethyl dimethoxysilane and the white carbon black and simultaneously reducing the number of the hydroxyl groups to achieve the hydrophobic effect, and then the surface of the white carbon black is grafted with a macromolecular group by utilizing n-octanol, so that the modified white carbon black has the hydrophobic and oleophilic properties, the wetting and dispersing effects of the white carbon black in the organic phase of the silicone rubber are improved, the binding capacity of the white carbon black and the methyl vinyl silicone rubber.

In order to achieve the second object, the invention provides the following technical scheme:

the preparation method of the modified white carbon black comprises the following preparation steps:

s1, uniformly mixing the fly ash and sodium carbonate, melting at 1300-1600 ℃ for 1-1.5 h, adding 80% of water by mass fraction, extracting, leaching, filtering and concentrating to obtain a semi-finished product of white carbon black;

s2, adding 20 mass percent of water into the semi-finished white carbon black to dissolve, adding p-toluenesulfonic acid to perform acid leaching for 5 to 9 hours, controlling the system temperature at 28 to 35 ℃, then heating to 50 to 80 ℃, adjusting the pH value to 5 to 7, and curing for 20 to 30 minutes to obtain a suspension;

and S3, adding dimethyl dimethoxy silane and ethanol into the suspension, performing ultrasonic dispersion for 20min-30min, heating to 100-120 ℃, stirring for reaction for 8-12 h, adding n-octanol, performing reflux water diversion for 4-5 h, cooling, filtering, washing and drying to obtain the modified white carbon black.

By adopting the technical scheme, sodium carbonate soda ash and p-toluenesulfonic acid are sequentially added to react with fly ash, so that a semi-finished white carbon black product is synthesized, and dimethyl dimethoxysilane and n-octanol modifier are simultaneously added into suspension liquid synthesized by the semi-finished white carbon black product to modify the white carbon black, so that the consumption of the p-toluenesulfonic acid can be saved, the process is simple, and the product cost is favorably reduced.

In order to achieve the third object, the invention provides the following technical solutions:

the silicon rubber for the rubber roller containing the modified white carbon black is prepared from the following raw materials in parts by weight:

methyl vinyl silicone rubber: 100 parts of (A);

modified white carbon black: 10-90 parts;

wherein the molar mass of the raw methyl vinyl silicone rubber is 30W-60W, and the mass percentage of vinyl in the methyl vinyl silicone rubber is 0.03% -5%.

By adopting the technical scheme, the modified white carbon black is used for replacing common white carbon black and hydroxyl-terminated polysiloxane, so that the resilience of the silicon rubber and the processability after the silicon rubber is placed for 100 days can be obviously improved, the modified white carbon black is modified by sequentially using dimethyl dimethoxysilane and n-octanol, the hydroxyl amount on the molecular surface of the white carbon black can be reduced, the white carbon black has hydrophobic and oleophilic properties, the formation of a coupling bond between the white carbon black and methyl vinyl silicone rubber is improved, and the vulcanization efficiency and the resilience are improved.

Further, the silicone rubber also comprises a release agent, wherein the weight part of the release agent is 0.01-0.5.

By adopting the technical scheme, the release agent is added into the silicon rubber, and has the functions of wetting and lubricating, so that the silicon rubber is not easy to decompose and wear, the tensile strength of the silicon rubber is improved, the release agent can migrate to the outer surface of the silicon rubber, the flow rate of a silicon rubber material in a mold cavity is slowed down, the molding cycle time is shortened, the silicon rubber is easy to mold and demold, and the demolding effect during silicon rubber processing is improved.

Further, the release agent is zinc stearate.

By adopting the technical scheme, the zinc stearate has lubricating and softening effects, the performance of the zinc stearate is more stable compared with other release agents, the zinc stearate has better combination effect with other components in the silicon rubber raw material, the performance of the modified white carbon black is not influenced, and the rebound resilience, the tensile strength and the tearing strength of the silicon rubber are optimal.

Further, the silicone rubber also comprises a heat-resistant agent, wherein the weight part of the heat-resistant agent is 0.5-5 parts.

By adopting the technical scheme, the tearing strength can be improved by adding the heat-resistant agent into the silicone rubber, and the heat-resistant agent can help the silicone rubber product to keep the dimensional stability and the lower heat shrinkage rate and improve the heat resistance of the silicone rubber.

Further, the heat-resistant agent is prepared from nano iron oxide, nano titanium oxide and nano cerium oxide in a mass ratio of 2:1:3, and mixing the components in a ratio of 3.

By adopting the technical scheme, the heat-resistant agent adopts the following components in percentage by mass: 1:3, the nano-material is generally a rare earth nano-material, has the characteristics of high surface activity, small size of nano-particles and the like, can permeate into a polymer chain, and enhances the stability among molecules; meanwhile, the rare earth element has a special complexing effect on silicon molecules, and can increase the crosslinking density of the silicon rubber material and the connection stability between molecular chains, so that the tearing strength of the silicon rubber is improved.

Further, the silicon rubber also comprises triethanolamine borate, and the weight part of the triethanolamine borate is 0.7-1.4.

By adopting the technical scheme, the triethanolamine borate does not influence the performances of other components of the silicone rubber, so that the tensile strength, hardness and resilience are kept optimal, and the lubricating and wear-resisting functions are realized, the self-adhesion of the silicone rubber can be improved, the combination degree of the silicone rubber roller and the iron core is improved, the influence on the polishing process of the silicone rubber roller is reduced, and the processability of the silicone rubber is improved.

In order to achieve the fourth object, the invention provides the following technical solutions:

a preparation method of silicon rubber for rubber rollers containing modified white carbon black comprises the following steps:

s1, adding the methyl vinyl silicone rubber and the modified white carbon black into a kneader, controlling the system temperature at 80-100 ℃, and mixing into a mass;

s2, putting the product into an oven for vulcanization, controlling the temperature of the system to rise to 140-160 ℃, and carrying out heat treatment for 1-3 h to obtain mixed glue solution;

and S3, after the step S2 is finished, injecting the mixed glue solution into a mold for molding, and obtaining the silicone rubber.

By adopting the technical scheme, the silicon rubber raw material components are added into the kneader to be mixed, stirred, vulcanized and polymerized, the operation steps are simple, and the production efficiency is improved.

Further, in step S1, a mold release agent, a heat resistance agent, and triethanolamine borate are added.

In conclusion, the invention has the following beneficial effects:

firstly, replacing common white carbon black and hydroxyl-terminated polysiloxane with modified white carbon black, so that the resilience and the processability of the silicone rubber after being placed for 100 days can be remarkably improved, combining dimethyl dimethoxysilane with the hydroxyl on the surface of the white carbon black, activating in advance, reducing the number of the hydroxyl, achieving a hydrophobic effect, and grafting a macromolecular group on the surface of the white carbon black by using n-octanol, so that the modified white carbon black has hydrophobic and oleophilic properties, the wetting and dispersing effects of the white carbon black in a silicone rubber organic phase are improved, the binding capacity of the white carbon black and methyl vinyl silicone rubber is improved, and the vulcanization efficiency and the resilience of the silicone rubber are improved;

secondly, sodium carbonate soda ash and p-toluenesulfonic acid are sequentially added to react with fly ash to synthesize a semi-finished white carbon black product, and dimethyl dimethoxy silane and n-octanol modifier are simultaneously added to suspension synthesized from the semi-finished white carbon black product to modify the white carbon black, so that the consumption of the p-toluenesulfonic acid can be saved, the process is simple, and the reduction of the product cost is facilitated;

thirdly, a release agent is added into the silicon rubber, the release agent has wetting and lubricating functions, so that the silicon rubber is not easy to decompose and wear, the tensile strength of the silicon rubber is improved, the release agent can migrate to the outer surface of the silicon rubber, the flow rate of a silicon rubber material in a mold cavity is slowed down, the molding cycle time is reduced, the silicon rubber is easy to mold and demold, and the demolding effect during silicon rubber processing is improved;

fourthly, the heat-resistant agent adopts nano iron oxide, nano titanium oxide and nano cerium oxide according to the mass ratio of 2:1:3, the nano-material is generally a rare earth nano-material, has the characteristics of high surface activity, small size of nano-particles and the like, can permeate into a polymer chain, and enhances the stability among molecules; meanwhile, the rare earth element has a special complexing effect on silicon molecules, and can increase the crosslinking density of the silicon rubber material and the connection stability between molecular chains, so that the tearing strength of the silicon rubber is improved.

Detailed Description

The present invention will be described in further detail with reference to examples.

The sources of the raw materials used in the following preparations, examples and comparative examples are shown in table 1 below:

TABLE 1 sources of raw materials

Preparation example

Preparation example 1

The modified white carbon black comprises the following raw materials by mass:

fly ash: 10 kg;

sodium carbonate: 35 kg;

p-toluenesulfonic acid: 31 kg;

dimethyl dimethoxy silane: 1.7 kg;

n-octanol: 59L;

ethanol: 26L;

water: 62L;

wherein the mesh number of the fly ash is 90 meshes.

The modified white carbon black is obtained by adopting the following preparation method, and comprises the following steps:

s1, uniformly mixing the fly ash and sodium carbonate, melting at 1300 ℃ for 1h, adding 80% of water by mass fraction, extracting, leaching, filtering and concentrating to obtain a semi-finished white carbon black product;

s2, adding 20 mass percent of water into the semi-finished white carbon black to dissolve, adding p-toluenesulfonic acid to perform acid leaching for 5 hours, controlling the system temperature at 30 ℃, then heating to 80 ℃, adjusting the pH value to 5, and curing for 30 minutes to obtain a suspension;

and S3, adding dimethyl dimethoxy silane and ethanol into the suspension, performing ultrasonic dispersion for 20min, heating to 120 ℃, stirring for reaction for 8h, then adding n-octanol, performing reflux and water diversion for 4h, cooling, filtering, washing and drying to obtain the modified white carbon black.

Preparation example 2

The modified white carbon black comprises the following raw materials by mass:

fly ash: 16 kg;

sodium carbonate: 28 kg;

p-toluenesulfonic acid: 43 kg;

dimethyl dimethoxy silane: 1.3 kg;

n-octanol: 62L;

ethanol: 24L;

water: 74L;

wherein the mesh number of the fly ash is 120 meshes.

The modified white carbon black is obtained by adopting the following preparation method, and comprises the following steps:

s1, uniformly mixing the fly ash and sodium carbonate, melting at 1600 ℃ for 1.5h, adding 80 mass percent of water for extraction and leaching, filtering and concentrating to obtain a semi-finished white carbon black product;

s2, adding 20% mass percent of water into the semi-finished white carbon black to dissolve, adding p-toluenesulfonic acid to perform acid leaching for 8 hours, controlling the system temperature at 18 ℃, then heating to 60 ℃, adjusting the pH value to 7, and curing for 25 minutes to obtain a suspension;

and S3, adding dimethyl dimethoxy silane and ethanol into the suspension, performing ultrasonic dispersion for 25min, heating to 110 ℃, stirring for reaction for 12h, then adding n-octanol, performing reflux and water diversion for 4h, cooling, filtering, washing and drying to obtain the modified white carbon black.

Preparation example 3

The modified white carbon black comprises the following raw materials by mass:

fly ash: 12 kg;

sodium carbonate: 45 kg;

p-toluenesulfonic acid: 48 kg;

dimethyl dimethoxy silane: 2.4 kg;

n-octanol: 81L;

ethanol: 36L;

water: 69L;

wherein the mesh number of the fly ash is 110 meshes.

The modified white carbon black is obtained by adopting the following preparation method, and comprises the following steps:

s1, uniformly mixing the fly ash and sodium carbonate, melting at the high temperature of 1400 ℃ for 1.2h, adding 80% of water by mass fraction, extracting, leaching, filtering and concentrating to obtain a semi-finished product of white carbon black;

s2, adding 20 mass percent of water into the semi-finished white carbon black to dissolve, adding p-toluenesulfonic acid to perform acid leaching for 9 hours, controlling the system temperature at 35 ℃, then heating to 50 ℃, adjusting the pH value to 6, and curing for 20 minutes to obtain a suspension;

and S3, adding dimethyl dimethoxy silane and ethanol into the suspension, performing ultrasonic dispersion for 30min, heating to 100 ℃, stirring for reaction for 10h, then adding n-octanol, performing reflux and water diversion for 5h, cooling, filtering, washing and drying to obtain the modified white carbon black.