Preparation method of styrenated hindered phenol or styrenated phenol antioxidant product

Abstract

The invention discloses a preparation method of a styrenated hindered phenol or styrenated phenol antioxidant product, belonging to the field of preparation process methods of polymer antioxidant products. The preparation method is characterized in that: o-tert-butyl phenol or phenol, p-cresol, o-cresol and m-cresol are used as raw materials, styrene is used as an alkylation reagent, an organic acid compound is used as a catalyst, a small amount of polymerization inhibitor is added, and the styrenated hindered phenol product or styrenated phenol product is prepared through catalytic alkylation reaction; a neutralizing and decolorizing agent is added to the styrenated product to deactivate the acidic catalyst and remove the coloring source material, thus obtaining a white-like or light yellow viscous liquid namely the styrenated phenol antioxidant product which has clear and transparent appearance, pH value of 6.5-7.5, storage stability and high use efficiency; and the styrenated phenol antioxidant product is free of water-soluble pollutants such as free phenol or methyl phenol, thereby solving the problem of environmental pollution caused by the use of the product in styrene butadiene rubber latex.

Description

technical field [0001] The invention belongs to the field of preparation process methods of polymer antioxidant products, in particular to a preparation method of styrenated hindered phenol antioxidant products and use in the production of styrene-butadiene rubber by an emulsion polymerization process. Background technique [0002] The styrenated hindered phenol product specifically refers to a reaction mixture obtained from the catalytic alkylation reaction of styrene and o-tert-butylphenol. It has similar physical and chemical properties to other styrenated phenolic compounds, and its appearance is light yellow and viscous. Liquid, belongs to the alkylphenol non-polluting polymer antioxidant, has the advantages of high efficiency, low toxicity, low price, etc. It is used as an anti-aging agent in synthetic rubber products obtained by emulsion polymerization, or as an antioxidant in lubricating oil. [0003] SBR is mainly used in fields such as automobile tires, industrial...

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Problems solved by technology

[0006] Shandong Chemical Industry, 1991, (2) 28-31; Progress in Fine Petrochemical Industry, 2009, 10 (1): 51-52 disclosed that phenol was used as raw material, benzene Ethylene is an alkylating agent, p-toluenesulfonic acid is a catalyst, and the alkylation reaction synthesizes styrenated phenol. The disadvantage is that the obtained product is either turbid, opaque, or dark in appearance. Phenol antiaging agent contains water-soluble pollutant phenol

[0007] Synthetic Chemistry, 2006, 14 (2): 196-199 discloses that phenol is used as a raw material, α-methylstyrene is used as an alkylating agent, phosphoric acid and ice Acetic acid mixture is used as a catalyst to carry out catalytic alkylation reaction to synthesize α-methyl styrenated phenol. The disadvantage is that the product is not clear and transparent or the appearance color is darker, and the obtained anti-aging agent still contains water-soluble pollutants. phenol

[0008]US Patent US2008 / 0207804A1, Fine Chemical Industry, 2003, 20, (8): 496-497, discloses the use of p-cresol As a raw material, styrene is an alkylating agent, and sulfonic acid compounds are used as a catalyst to carry out a catalytic alkylation reaction to synthesize styrenated p-cresol. The disadvantage is that the product is not clear and transparent or has a darker appearance. In addition, styrene and p-cresol are used as raw materials to synthesize styrenated p-cresol. In the reaction system, there is an equilibrium relationship between the reaction raw material p-cresol and the product styrenated p-cresol, and the obtained antioxidant benzene cannot be avoided. Ethylene p-cresol still contains water-soluble pollutant p-cresol, the resulting phenol-containing wastewater is very difficult to treat, and direct discharge will cause serious pollution to the environment

[0010]1. The raw material prices of p-cresol and o-cresol are relatively high, and the final styrenated p-cresol or styrenated o-cresol products are obtained The price is very high, no matter which kind of antioxidant is used to produce styrene-butadiene rubber, it will lack competitiveness due to economic factors, so that the two styrenated methyl phenol antioxidant products cannot be used in styrene-butadiene rubber

[0011]2. Use a mixture of phenol, p-cresol, and o-cresol as raw materials to prepare styrenated phenolic mixture antioxidants, but it is difficult to make phenol, p-cresol Base phenol and o-cresol react completely under certain reaction conditions, leading to final antioxidant products containing free phenol or methyl phenol, which are water-soluble pollutants

[0012]3. Using trifluoromethanesulfonic acid, trichloromethanesulfonic acid, methanesulfonic acid, ethylsulfonic acid and other sulfonic acid compounds as catalysts, it has acidic strength High, strong catalytic activity, easy to carry out catalytic alkylation reaction, although the catalyst content of the final product is less (1~1000wppm), but it is not like CN101688143A that the use of this type of catalyst "basically does not cause color, or can be prepared with Very low-color styrenated phenolic composition", experiments have verified that the appearance of the product obtained by this technology is pink, and after being placed at room temperature for about a month, the product will spontaneously increase in viscosity under the action of an acidic catalyst and become less Clear, transparent and turbid, indicating that the product contains insoluble particles. These phenomena indicate the strong oxidative properties of strong acidic catalysts such as trifluoromethanesulfonic acid, resulting in darker color during the preparation of the product and damage to the product during later storage.

[0016] As we all know, when an acidic catalyst is selected, the catalytic reaction between phenolic compounds and olefinic alkylating agents is an electrophilic substitution reaction of alkylating agents on the aromatic ring, and the hydroxyl The group is used as the first type of substituent, so that the reaction product is mainly an isomer with one para-position and two ortho-positions of the phenolic hydroxyl group replaced by an alkylating agent. After completing an alkyl substitution, the aromatic ring is deactivated and is After the two alkyl groups are substituted, further passivation is performed, so it is relatively easy to obtain monosubstituted and disubstituted alkylated products, but it is difficult to obtain trisubstituted alkylated products; The base-based reagent reaction first obtains the para-position substitution product, and when the para-position is mostly occupied, the next stage reaction is continued to obtain the ortho-position product, but at the same time, the activation energy required for the reaction increases, or the reaction temperature needs to be increased or the amount of the catalyst must be increased. to fulfill

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