阅读说明：本技术 一种用于橡胶补强的白炭黑的处理方法 (Processing method of white carbon black for rubber reinforcement ) 是由 刘艺 于 2019-09-10 设计创作，主要内容包括：本发明公开了一种用于橡胶补强的白炭黑的处理方法,具体方法如下：1)向海藻酸钠的乙醇悬浮液中加入高碘酸钠,制得部分氧化的海藻酸钠；2)将纳米硫化铜和羟基磷灰石加入到水中,加入聚乙二醇和1)中产物,制得复合水溶胶,然后加入到盛有白炭黑的容器中,制得复合水溶胶/白炭黑复合物；3)将2)中产物分别经氯化钙和氯化钠溶液处理得到复合水凝胶/白炭黑复合物；4)经复合物经溶剂置换后加入到混合溶液中,经搅拌、干燥即可。本发明提供的处理方法,可以有效的提高白炭黑同聚合物的相容性和分散性,有效的改善了白炭黑与聚合物的界面粘结,提高了白炭黑在聚合物中的补强效果,应用在橡胶中,可以使橡胶的性能得到显著提升。(the invention discloses a method for treating white carbon black for rubber reinforcement, which comprises the following steps: 1) adding sodium periodate into the ethanol suspension of the sodium alginate to prepare partially oxidized sodium alginate; 2) adding nano copper sulfide and hydroxyapatite into water, adding polyethylene glycol and the product obtained in step 1) to prepare composite hydrosol, and then adding the composite hydrosol and the composite silica into a container containing silica to prepare a composite hydrosol/silica composite; 3) respectively treating the products in the step 2) with calcium chloride and sodium chloride solutions to obtain a composite hydrogel/white carbon black composite; 4) and (3) replacing the compound with a solvent, adding the mixture into the mixed solution, stirring and drying. The processing method provided by the invention can effectively improve the compatibility and the dispersibility of the white carbon black and the polymer, effectively improve the interface bonding of the white carbon black and the polymer, improve the reinforcing effect of the white carbon black in the polymer, and obviously improve the performance of rubber when being applied to the rubber.)

1. A treatment method of white carbon black for rubber reinforcement is characterized by comprising the following specific treatment methods:

1) Adding sodium periodate into ethanol suspension of sodium alginate, stirring at room temperature in dark condition for 6-10 hr at rotation speed of 100-150r/min, dialyzing the reaction product in distilled water until no free periodate exists in the dialyzate, and freeze drying at-35- -45 deg.C for 20-25 hr to obtain partially oxidized sodium alginate;

2) Adding nano copper sulfide and hydroxyapatite into deionized water, oscillating and dispersing for 20-30min under 250-300W ultrasonic wave to prepare mixed dispersion liquid, then adding partially oxidized sodium alginate and polyethylene glycol, continuing oscillating and dispersing for 5-10min at normal temperature to prepare composite hydrosol, then adding the composite hydrosol into a container containing white carbon black, enabling the composite hydrosol to submerge the white carbon black, then closing the container, adjusting the vacuum pressure of the closed container to-0.01-0.05 MPa by using a vacuum pump, and carrying out impregnation and adsorption for 2-4h to prepare a composite hydrosol/white carbon black compound;

3) Carrying out suction filtration on the composite hydrosol/white carbon black compound by using a vacuum suction filter, wherein the vacuum suction filtration pressure is-0.02-0.04 MPa, the suction filtration time is 1-2min, then adding a product after suction filtration into a calcium chloride solution, standing at room temperature for 5-8h, putting the obtained gel into a sodium chloride solution, soaking at constant temperature of 35-40 ℃ for 25-30d, filtering, and washing the product with distilled water for 15-20min to obtain the composite hydrogel/white carbon black compound;

4) respectively soaking the composite hydrogel/white carbon black compound in absolute ethyl alcohol and n-hexane solution at normal temperature, carrying out solvent replacement for 20-25h to prepare a composite alcogel/white carbon black compound, then adding the composite alcogel/white carbon black compound into a mixed solution consisting of trimethylchlorosilane and n-hexane, stirring for 15-20h at normal temperature at a rotating speed of 80-130r/min, and drying the filtered product for 3-5h at 80-120 ℃.

2. the method for processing white carbon black for rubber reinforcement according to claim 1, wherein in step 1), the mass percent of sodium alginate in the ethanol suspension of sodium alginate is 3-5%; the oxidation degree of the partially oxidized sodium alginate is 5-7%.

3. The method for processing white carbon black for rubber reinforcement according to claim 1, wherein in the step 2), the mass concentration of hydroxyapatite is 40-50g/L, the mass concentration of sodium alginate is 20-25g/L, the mass concentration of polyethylene glycol is 50-80g/L, and the mass concentration of nano copper sulfide is 3-6 g/L; the white carbon black is precipitated white carbon black, and the mass volume ratio of the precipitated white carbon black to the composite hydrosol is 1:30-40 g/ml.

4. The method for processing white carbon black for rubber reinforcement according to claim 1, wherein in the step 3), the mass percentage of the calcium chloride solution is 1-2%, and the mass-to-volume ratio of the calcium chloride solution to the suction filtration product is 1:20-30 g/ml; the concentration of the sodium chloride solution is 0.1-0.2mol/L, and the mass-volume ratio of the sodium chloride solution to the gel is 1:40-50 g/ml.

5. the method for processing silica white for rubber reinforcement according to claim 1, wherein in the step 4), the mass-to-volume ratios of the composite hydrogel/silica white composite to the absolute ethyl alcohol and the n-hexane are 1:40-50g/ml and 1:35-45g/ml respectively; the mass volume ratio of the composite alcogel/white carbon black compound to the mixed solution is 1:50-70g/ml, wherein the volume ratio of trimethylchlorosilane to normal hexane in the mixed solution is 1: 1-1.5; in the solvent replacement process, the solvent is replaced at intervals of 6-8 h.

Technical Field

The invention belongs to the technical field of white carbon black, and particularly relates to a processing method of white carbon black for rubber reinforcement.

Background

White carbon black is a general term for white powdery X-ray amorphous silicic acid and silicate products, mainly referring to precipitated silica, fumed silica and ultrafine silica gel, and also including powdery synthetic aluminum silicate, calcium silicate, and the like. White carbon black is a porous substance, and the composition of the white carbon black can be represented by SiO2 & nH2O, wherein nH2O exists in the form of surface hydroxyl. It is soluble in caustic alkali and hydrofluoric acid, and insoluble in water, solvent and acid. High-temperature resistance, non-combustion, tastelessness, odorless and good electrical insulation.

The white carbon black has a special surface structure (with surface hydroxyl and absorbed water), a special particle form (small particles, large specific surface area and the like) and unique physical and chemical properties. Therefore, the white carbon black has important inorganic silicon compounds with excellent performances such as porosity, high dispersibility, light weight, good chemical stability, high temperature resistance, non-combustion, good electrical insulation property and the like. Due to the characteristics, the white carbon black is widely applied to various fields such as rubber, plastics, coatings, medicines, daily chemical industry and the like. However, the traditional white carbon black is hydrophilic due to the polysiloxane in the white carbon black, the active silanol group on the outer surface and the water adsorption property of the traditional white carbon black, and the white carbon black is difficult to wet and disperse in an organic phase after the white carbon black is added into materials such as rubber and the like. Moreover, the white carbon black has hydroxyl on the surface, so the surface energy is larger, and the aggregate always tends to agglomerate, thereby the application performance of the product is influenced. Therefore, in order to improve the dispersibility and compatibility of the white carbon black in the polymer, the white carbon black needs to be modified.

At present, the modification treatment of the white carbon black mostly adopts a surface coating treatment method, for example, application No. CN201410175796.4 discloses a carbon-coated white carbon black, application No. CN201810877910.6 discloses a treatment method of the white carbon black, and a carbon layer is coated on the surface of the white carbon black, so that the agglomeration phenomenon of the white carbon black is improved, but the carbon-coated white carbon black method causes the surface of the white carbon black to be coated with other substances, so that the white carbon black is separated from the polymer interface, and the white carbon black cannot be directly contacted with the polymer, so that the enhancing effect of the white carbon black in the polymer is unsatisfactory.

Disclosure of Invention

The invention aims to provide a method for treating white carbon black for rubber reinforcement aiming at the existing problems.

the invention is realized by the following technical scheme:

a treatment method of white carbon black for rubber reinforcement comprises the following specific treatment methods:

1) Adding sodium periodate into ethanol suspension of sodium alginate, stirring at room temperature in dark condition for 6-10 hr at rotation speed of 100-150r/min, dialyzing the reaction product in distilled water until no free periodate exists in the dialyzate, and freeze drying at-35- -45 deg.C for 20-25 hr to obtain partially oxidized sodium alginate; by utilizing the strong oxidation of sodium periodate, cis-vicinal diol in a sodium alginate uronic acid structure can be subjected to carbon-carbon bond breakage to generate two aldehyde groups, so that sodium alginate is hydrolyzed in a sodium chloride solution, and is easy to degrade;

2) adding nano copper sulfide and hydroxyapatite into deionized water, oscillating and dispersing for 20-30min under 250-300W ultrasonic wave to prepare mixed dispersion liquid, then adding partially oxidized sodium alginate and polyethylene glycol, continuing oscillating and dispersing for 5-10min at normal temperature to prepare composite hydrosol, then adding the composite hydrosol into a container containing white carbon black, enabling the composite hydrosol to submerge the white carbon black, then closing the container, adjusting the vacuum pressure of the closed container to-0.01-0.05 MPa by using a vacuum pump, and carrying out impregnation and adsorption for 2-4h to prepare a composite hydrosol/white carbon black compound; the method comprises the steps of forming composite hydrosol by adopting hydroxyapatite, nano copper sulfide, sodium alginate and polyethylene glycol, enabling the composite hydrosol to penetrate into and fill in pores of the white carbon black through vacuum impregnation adsorption, enabling the hydrosol to be capable of forming hydrogen bond bonding with hydroxyl on the surface of the white carbon black, and enabling the hydrosol to be attached to the surface of the white carbon black to form a sol film;

3) Carrying out suction filtration on the composite hydrosol/white carbon black compound by using a vacuum suction filter, wherein the vacuum suction filtration pressure is-0.02-0.04 MPa, the suction filtration time is 1-2min, then adding a product after suction filtration into a calcium chloride solution, standing at room temperature for 5-8h, putting the obtained gel into a sodium chloride solution, soaking at constant temperature of 35-40 ℃ for 25-30d, filtering, and washing the product with distilled water for 15-20min to obtain the composite hydrogel/white carbon black compound; the excess hydrosol on the surface of the composite hydrosol/white carbon black composite can be removed by suction filtration; the composite hydrogel is formed by crosslinking hydroxyapatite, nano copper sulfide, sodium alginate and polyethylene glycol, wherein the hydroxyapatite and the sodium alginate can form a scaffold structure through crosslinking, and a polymer network formed by the added polyethylene glycol in the composite gel can provide enough bonding strength for the interior of the composite gel, so that the stability of the scaffold structure of the composite gel can be improved, and the copper sulfide can be better fixed in the scaffold structure; copper ions in the added copper sulfide can be subjected to coordination crosslinking with a coordination side group contained in the rubber, so that the compatibility of the white carbon black with the rubber material can be improved, the escape of the white carbon black is avoided, the stability of the white carbon black in the rubber material is improved, and meanwhile, the mechanical property of the rubber material can be further improved as the bond energy of the coordination bond is higher than that of a hydrogen bond; by soaking in a sodium chloride solution, sodium alginate in the hydrogel is subjected to oxidation treatment and is easy to degrade by a hydrolysis mechanism, so that the hydrogel formed on the surface of the compound is easy to hydrolyze and degrade, the hydrogel formed on the surface of the compound can be removed, the influence of the hydrogel attached to the surface of white carbon black on the reinforcing effect of the white carbon black in rubber can be avoided, and finally, a filling type compound hydrogel/white carbon black compound is formed;

4) respectively soaking the composite hydrogel/white carbon black compound in absolute ethyl alcohol and n-hexane solution at normal temperature, carrying out solvent replacement for 20-25h to prepare a composite alcogel/white carbon black compound, then adding the composite alcogel/white carbon black compound into a mixed solution consisting of trimethylchlorosilane and n-hexane, stirring for 15-20h at normal temperature at a rotating speed of 80-130r/min, and drying the filtered product for 3-5h at 80-120 ℃; the water in the hydrogel network structure is replaced by the organic solvent with low surface tension, so that the volume shrinkage of the hydrogel in the drying process can be reduced, the collapse of the composite hydrogel support structure can be avoided, and the escape of copper sulfide in the composite hydrogel can be avoided; the trimethyl chlorosilane is adopted to modify the composite alcogel filled in the white carbon black, and polar group hydroxyl on the surface of the alcogel is replaced by nonpolar group methyl, so that gel shrinkage deformation caused by drying can be avoided, and the damage of a composite gel support structure can be prevented.

Preferably, the method for processing the white carbon black for rubber reinforcement comprises the following steps of 1), wherein in an ethanol suspension of sodium alginate, the mass percent of the sodium alginate is 3-5%; the oxidation degree of the partially oxidized sodium alginate is 5-7%.

Preferably, in the step 2), in the composite hydrosol, the mass concentration of hydroxyapatite is 40-50g/L, the mass concentration of sodium alginate is 20-25g/L, the mass concentration of polyethylene glycol is 50-80g/L, and the mass concentration of nano copper sulfide is 3-6 g/L; the white carbon black is precipitated white carbon black, and the mass volume ratio of the precipitated white carbon black to the composite hydrosol is 1:30-40 g/ml.

Preferably, in the step 3), the mass percentage of the calcium chloride solution is 1-2%, and the mass volume ratio of the calcium chloride solution to the suction filtration product is 1:20-30 g/ml; the concentration of the sodium chloride solution is 0.1-0.2mol/L, and the mass-volume ratio of the sodium chloride solution to the gel is 1:40-50 g/ml.

Preferably, in the step 4), the mass-volume ratios of the composite hydrogel/white carbon black compound to the absolute ethyl alcohol and the normal hexane are 1:40-50g/ml and 1:35-45g/ml respectively; the mass volume ratio of the composite alcogel/white carbon black compound to the mixed solution is 1:50-70g/ml, wherein the volume ratio of trimethylchlorosilane to normal hexane in the mixed solution is 1: 1-1.5; (ii) a In the solvent replacement process, the solvent is replaced at intervals of 6-8 h.

compared with the prior art, the invention has the following advantages:

the method for processing the white carbon black provided by the invention has the advantages that the composite hydrogel is filled in the pores of the white carbon black, the metallic copper ions in the composite hydrogel and the coordinatable side group contained in the rubber are utilized to carry out coordination crosslinking, so that the compatibility of the white carbon black and the rubber material can be improved, the stability of the white carbon black in the rubber material can be improved, the mechanical property of the rubber material can be further improved, the reinforcing effect of the white carbon black can be increased, in addition, in the processing process, the active hydroxyl on the surface of the white carbon black is consumed, the active hydroxyl content on the surface of the white carbon black is reduced, the surface energy of the white carbon black is reduced, the agglomeration phenomenon is not easy to occur, the dispersibility of the white carbon black in an organic phase can be improved, the interface bonding of the white carbon black and the polymer is effectively improved, the white carbon black is directly, when the rubber is applied to rubber, the performance of the rubber can be obviously improved.

Detailed Description

The present invention will be further described with reference to specific embodiments.