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CN-121991521-A - Modified lignin/regenerated carbon black premix, tread rubber composition and preparation method thereof

CN121991521ACN 121991521 ACN121991521 ACN 121991521ACN-121991521-A

Abstract

The invention discloses a modified lignin/regenerated carbon black premix, a tread rubber composition and a preparation method thereof, belonging to the technical field of rubber materials for tires, aiming at the problems of low surface activity, easy agglomeration, insufficient reinforcement, large heat generation, strong polarity of lignin, easy agglomeration and poor compatibility of the regenerated carbon black, the invention provides a modified lignin/surface activated regenerated carbon black premix, a tread rubber composition and a preparation method. 3-mercaptopropyl triethoxy silane is adopted to graft and modify lignin, hydrogen peroxide is used for oxidation and activation to regenerate carbon black, and the carbon black is acidified to pH 4.0-4.5 after wet shearing and dispersion in ethanol water, induced deposition is carried out, thus obtaining a premix, and then the tread rubber composition is prepared by internal mixing. The filler dispersion and interface combination can be improved, the processing safety window is enlarged, the reinforcing, wear-resisting and heat aging resisting performances are improved, meanwhile, the heat generation is reduced, the rebound is improved, and the high filling application of the regenerated carbon black is facilitated.

Inventors

  • PENG YANLEI
  • XUAN ZHAOMIN
  • PENG WENFENG
  • YIN FENG
  • BING ZIYU

Assignees

  • 山东东岳科技发展有限公司

Dates

Publication Date
20260508
Application Date
20260324

Claims (10)

  1. 1. The modified lignin/regenerated carbon black premix is characterized by comprising the following raw materials in parts by mass: 10-15 parts of modified lignin; 40-50 parts of surface-activated regenerated carbon black; The modified lignin is prepared by the following steps: Adding alkali lignin into deionized water to prepare alkali lignin slurry with the mass fraction of 10%, adjusting the pH value of the alkali lignin slurry to 10.5-12.0, and stirring at 60-75 ℃ for 30-60 min to obtain lignin activation liquid; And A2, adding absolute ethyl alcohol into the lignin activation solution, stirring at room temperature for 5-10 min after the addition, adding 3-mercaptopropyl triethoxysilane accounting for 12% -15% of the alkali lignin mass into the lignin activation solution, heating the system to 60-70 ℃ after the addition, stirring at constant temperature for reacting for 1-2 h, adjusting the pH value of the system to 6-7 after the reaction is finished, stirring for 10-20min, standing until precipitation is not generated, filtering, washing with water, drying in vacuum, crushing, and sieving with a 100-mesh sieve to obtain the modified lignin.
  2. 2. The modified lignin/regenerated carbon black premix according to claim 1, wherein the volume ratio of lignin activation solution to absolute ethanol in step A2 is 10 (2-3).
  3. 3. The modified lignin/reclaimed carbon black premix of claim 1 wherein the surface activated reclaimed carbon black is prepared by: Adding regenerated carbon black into deionized water to prepare carbon black slurry with the mass fraction of 10-15 wt%, heating the carbon black slurry to 50-70 ℃, adding hydrogen peroxide solution with the mass fraction of 30-wt%, and stirring at constant temperature for 30-90 min to obtain a mixed solution; And B2, regulating the pH value of the mixed solution to 6-8, stirring at constant temperature for 5-10 min after the mixed solution is finished, filtering, washing with water, drying in vacuum, crushing and sieving with a 100-mesh sieve to obtain the surface activated regenerated carbon black.
  4. 4. A modified lignin/regenerated carbon black premix according to claim 3 wherein the mass ratio of hydrogen peroxide solution to regenerated carbon black in step B1 is (1-4): 100.
  5. 5. The modified lignin/renewable carbon black premix of claim 1 wherein the modified lignin/renewable carbon black premix is prepared by the steps of: Step C1, weighing the raw materials according to parts by mass, adding surface activated regenerated carbon black into an ethanol water solution with the volume fraction of 60% at room temperature to obtain slurry, shearing and dispersing the slurry for 10-20 min at 2000-4000 rpm, adding modified lignin into the slurry, and continuing shearing and dispersing for 10-20 min to obtain a compound; Step C2, stirring and adding a hydrochloric acid solution with the mass fraction of 5wt% into the compound, adjusting the pH value of the system to 4.0-4.5, and stirring for 20-40 min at room temperature after the adjustment is finished to obtain a prepolymer; And step C3, filtering the prepolymer, washing the prepolymer with water to be neutral, drying the prepolymer in vacuum at 80 ℃, crushing the prepolymer, and sieving the crushed prepolymer with a 800-mesh sieve to obtain the modified lignin/regenerated carbon black premix.
  6. 6. The modified lignin/regenerated carbon black premix of claim 5 wherein the volume fraction of the aqueous ethanol solution of step C1 and the surface activated regenerated carbon black are present in a solids to liquid ratio of 10ml to 3g.
  7. 7. Use of the modified lignin/reclaimed carbon black premix according to any one of claims 1 to 6 in a tread rubber composition, characterized in that the tread rubber composition comprises the following raw materials in parts by mass: 100 parts of natural rubber; 20-70 parts of modified lignin/regenerated carbon black premix; 330-60 parts of carbon black N; 10-20 parts of TDAE oil; 3-6 parts of zinc oxide; 1-3 parts of stearic acid; Age resister 4020-3 parts; 1-3 parts of an anti-aging agent 4010 NA; 0.5-3 parts of paraffin; 1-2.5 parts of sulfur; 0.8-2.5 parts of accelerator NS; 0.1-0.5 parts of scorch retarder CTP.
  8. 8. The use of a modified lignin/renewable carbon black premix according to claim 7 in a tread rubber composition, wherein the method for preparing said tread rubber composition comprises the steps of: S1, mixing by adopting an internal mixer, adding natural rubber, pressing down a pressing block for 40-50 seconds, lifting the pressing block, adding a modified lignin/regenerated carbon black premix, carbon black N330, zinc oxide, stearic acid, an anti-aging agent 4020 and an anti-aging agent 4010NA, pressing down the pressing block for 60-80 seconds, lifting the pressing block, adding TDAE oil and paraffin, pressing down the pressing block for 60-80 seconds, lifting the pressing block, cleaning, pressing down the pressing block for 60-80 seconds, controlling the rubber discharging temperature to 145-155 ℃, lifting the pressing block, discharging rubber, blanking, and standing to obtain a rubber compound; S2, cooling and standing the rubber compound for 5-6 hours, mixing by adopting an internal mixer, adding the rubber compound, sulfur, an accelerator NS and a scorch retarder CTP, pressing down the pressing block for 40 seconds, lifting up the pressing block, pressing down the pressing block for 40 seconds, controlling the rubber temperature to be 90-110 ℃, lifting up the pressing block, discharging rubber, discharging and standing to obtain the tread rubber composition.
  9. 9. The use of a modified lignin/regenerated carbon black premix according to claim 8 in tread rubber compositions wherein the internal mixer in S1 has an initial temperature of 80 to 95 ℃ and a rotor speed of 40 to 60 rpm.
  10. 10. The use of a modified lignin/regenerated carbon black premix according to claim 8 in tread rubber compositions wherein the internal mixer rotor speed in S2 is 15-25 rpm.

Description

Modified lignin/regenerated carbon black premix, tread rubber composition and preparation method thereof Technical Field The invention belongs to the technical field of rubber materials for tires, and particularly relates to a modified lignin/regenerated carbon black premix, a tread rubber composition and a preparation method thereof. Background The regenerated carbon black (rCB) is derived from thermal cracking of waste tires, has the advantages of environmental protection and cost, but generally has the problems of (1) low surface activity, high inorganic ash content, low structural degree, easy agglomeration in rubber, poor reinforcing effect, large heat generation, (2) large batch fluctuation, poor dynamic stability of rubber sizing material performance, easy uneven vulcanization, high hysteresis loss and the like in a high-filling system. The rCB is upgraded and modified, and the deep processing high-value utilization of rCB is promoted, so that the problems are concerned by domestic and foreign researches and are urgently solved. Lignin is the second largest biomass resource in nature and has a hindered phenol structure, so that the lignin has the functions of ultraviolet shielding, antioxidation, photothermal conversion and the like, but contains a large number of active groups such as hydroxyl, carboxyl and the like in molecules, has larger intermolecular acting force, is easy to agglomerate in rubber, and has low utilization efficiency. Lignin can form weak polar interactions (such as Van der Waals force and pi-pi accumulation) with rCB surfaces by virtue of the flexibility of a high molecular chain, and is physically adsorbed on rCB particle surfaces, and is partially wrapped or embedded in an aggregate gap of carbon black, so that the binding force between rCB and a rubber matrix is improved. However, the prior art usually adopts a method of mixing lignin plus rCB directly by a dry method or premixing a single material, and the method is mostly in a physical mixing level, so that the problems of rCB low activity, difficult dispersion, easy aggregation of lignin, poor compatibility and the like are difficult to solve, the interfacial compatibility of the two materials and a rubber matrix is influenced, and the application of the two materials in the rubber industry is limited. Therefore, the lignin and rCB processing method with simple development process and excellent reinforcing effect is a key technology for realizing the large-scale application of the lignin and rCB processing method in general rubber. Disclosure of Invention The invention aims to provide a modified lignin/regenerated carbon black premix, a tread rubber composition and a preparation method thereof, so as to realize: (1) The dispersibility and the reinforcing effect of the regenerated carbon black (rCB) are improved, and the heat generation and the rolling resistance of the rubber material are reduced; (2) The performance stability and the heat aging resistance of the rubber material are improved; (3) The capacity expansion increment of the regenerated carbon black (rCB) is realized, and the processing safety window is maintained. The aim of the invention can be achieved by the following technical scheme: The modified lignin/regenerated carbon black premix comprises the following raw materials in parts by mass: 10-15 parts of modified lignin; 40-50 parts of surface-activated regenerated carbon black; The modified lignin is prepared by the following steps: Adding alkali lignin into deionized water to prepare alkali lignin slurry with the mass fraction of 10%, adjusting the pH value of the alkali lignin slurry to 10.5-12.0, and stirring at 60-75 ℃ for 30-60 min to obtain lignin activation liquid; And A2, adding absolute ethyl alcohol into the lignin activation solution, stirring at room temperature for 5-10 min after the addition, adding 3-mercaptopropyl triethoxysilane accounting for 12% -15% of the alkali lignin mass into the lignin activation solution, heating the system to 60-70 ℃ after the addition, stirring at constant temperature for reacting for 1-2 h, adjusting the pH value of the system to 6-7 after the reaction is finished, stirring for 10-20min, standing until precipitation is not generated, filtering, washing with water, drying in vacuum, crushing, and sieving with a 100-mesh sieve to obtain the modified lignin. Further, in the step A2, the volume and the dosage ratio of the lignin activating solution to the absolute ethyl alcohol is 10 (2-3). Further, the surface-activated regenerated carbon black is prepared by the steps of: Adding regenerated carbon black into deionized water to prepare carbon black slurry with the mass fraction of 10-15 wt%, heating the carbon black slurry to 50-70 ℃, adding hydrogen peroxide solution with the mass fraction of 30-wt%, and stirring at constant temperature for 30-90 min to obtain a mixed solution; And B2, regulating the pH value of the mixed solution to 6-8, stirring at constant te