Preparation method of pentaerythritol triallyl ether

Abstract

The invention provides a pentaerythritol triallyl ether preparation method, and the method comprises: S1, adding pentaerythritol monoallyl ether and sodium hydroxide into a reaction kettle, heating, carrying out a degassing and dehydration reaction for 3-7 h, slowly adding allyl chloride into the reaction kettle, and carrying out a thermal insulation reaction for 3-6 h; S2, performing cooling to below 35 DEG C, adding water into sodium chloride with the same amount of substance as sodium hydroxide in S1 to prepare a sodium chloride saturated solution, standing for layering, discharging a lower-layer aqueous solution, and reserving an upper-layer semi-finished product pentaerythritol diallyl ether; S3, adding sodium hydroxide into the semi-finished product, and repeating the steps S1 and S2to obtain a pentaerythritol triallyl ether crude product. According to the process, a phase transfer catalyst is not needed, so that the cost is saved; compared with the existing process, the feedingof sodium hydroxide and allyl chloride is greatly reduced, and one hydroxyl group is averagely excessive by 2.5% in the reaction; feeding is reduced, by-products are reduced, rectification is not needed, direct post-treatment can be achieved, and cost is further saved.

Description

technical field [0001] The invention relates to the field of chemical industry, in particular to a preparation method of pentaerythritol triallyl ether. Background technique [0002] Pentaerythritol allyl ether is a chemical intermediate with a wide range of uses. It is often used as a crosslinking agent to prepare acrylic polymer thickeners and superabsorbent resins. It is also used in unsaturated polyesters, polyurethane resins, and cyclic In the synthesis of polymers such as epoxy resins and UV curable resins, the polymers are self-drying. [0003] The preparation method of pentaerythritol allyl ether reported at present is mainly based on the Williamson (Williamson) synthesis method. The Japanese patent with publication number JP63162640 uses the method of adding alkali metal hydroxide aqueous solution in batches to prepare pentaerythritol allyl ether, but due to insufficient contact between the sodium salt of pentaerythritol and allyl chloride, the product yield is low...

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Problems solved by technology

The Japanese patent with publication number JP63162640 uses the method of adding alkali metal hydroxide aqueous solution in batches to prepare pentaerythritol allyl ether, but due to insufficient contact between the sodium salt of pentaerythritol and allyl chloride, the product yield is low and the production cost is high; U.S. Patent No. 3,428,693 discloses the use of a large amount of dimethyl sulfoxide as a solvent, and the final product triether content is low, and due to the use of a large amount of organic solvent, post-processing is difficult; the Chinese patent with publication number CN 1944502A adopts a pressurizing device to etherify The reaction is carried out at 0.2MPa, the equipment investment is large, the reaction conversion rate is not high, and the phase transfer catalyst used is PEG200-PEG1000, which will react with raw materials and reduce the yield; Chinese patent CN 101200413 publicly selects quarter Ammonium salts are used as phase transfer catalysts, but the price of quaternary ammonium salt phase transfer catalysts is relatively high and the dosage is large. On the one hand, the use of quaternary ammonium salts is not conducive to the recovery and utilization of phase transfer catalysts; on the other hand, some parts will remain in the product after decomposition , so that product quality is affected

[0004] The above-mentioned preparation method of pentaerythritol allyl ether has many steps in the production process, high energy consumption, incomplete utilization of raw materials, high cost of phase transfer catalyst, difficult recovery, low product conversion rate, high chroma, many impurities, and three ethers. The disadvantage of low content can not meet the demand of unsaturated resin industry for high-quality crosslinking agent

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