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Preparation of high-purity 1,4-diacetylene benzene

A technology of diethynylbenzene and divinylbenzene, which is applied in the field of high purity 1, can solve the problems of complex high vacuum rectification equipment and undisclosed high purity, etc.

Inactive Publication Date: 2005-10-12
EAST CHINA UNIV OF SCI & TECH +1
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] British Patent GB1313524 discloses a kind of synthetic method of diethynyl benzene, and U.S. Patent No. 4,997,991 and US 4,120,909 also disclose a kind of synthetic method of diethynyl benzene, but these patents only report mixed diethynyl benzene (mainly 1 , 3 / 1, the preparation method of 4-mixed diethynylbenzene), although the obtained 1,3 / 1,4-mixed diethynylbenzene contains 1,4-diethynylbenzene, but due to the boiling point of both so close that it's hard to separate the two
These patents do not disclose the preparation of high-purity 1,4-diethynylbenzene, even for the preparation of 1,3 / 1,4-mixed diethynylbenzene, because they are easy to polymerize at a higher temperature, so in the preparation The process requires a complex high-vacuum rectification device

Method used

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  • Preparation of high-purity 1,4-diacetylene benzene

Examples

Experimental program
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Effect test

Embodiment 1

[0019] (1) Bromination of divinylbenzene

[0020] In 200ml of carbon tetrachloride, add 80g of industrial-grade mixed divinylbenzene (produced by Shandong Dongda Chemical Industry (Group) Company, which contains 1,3-divinylbenzene 54.7%, 1,4-divinylbenzene 25.2%) %, ethylvinylbenzene 18%, diethylethylbenzene and ethylbenzene 2.1%), under the condition of avoiding light, slowly add 164g liquid bromine dropwise while stirring, continue stirring for 1.5 hours after the dropwise addition is completed, at this time A large amount of white precipitate was formed, and TLC showed that the reaction was complete. After filtration, the filter cake was washed with carbon tetrachloride, and after drying, 48 g of white solid (1,4-bis-α, β-dibromoethylbenzene) was obtained. Merge the filtrate and the washing liquid to distill off the organic solvent, then distill under reduced pressure to remove the material with a boiling point lower than 160 ℃ / 2mmHg, to obtain 134g viscous liquid (1.3-bis-...

Embodiment 2

[0024] In 200ml of methanol, slowly add 58g (1.07mol) of sodium methylate under stirring, add 48g of 1,4-bis-alpha, beta-dibromoethylbenzene obtained by step (1) in Example 1 after dissolving completely, and heat Refluxed for 2 hours, a large amount of white solid was formed, TLC showed that the reaction was complete, filtered, the filter cake was washed with methanol, and dried to obtain a white solid, which was sodium bromide. Combine the washing liquid and the filtrate, distill off the methanol, distill the residue with water steam, pass hot water at 80°C in the condenser tube, and obtain the azeotrope of 1,4-diethynylbenzene and water, which will become a liquid-solid two-phase after cooling, filter, The filter cake is 1,4-diethynylbenzene; the filtrate is extracted with ether, and the ether in the extract is distilled off to obtain 1,4-diethynylbenzene. Carbon chloride was recrystallized to obtain 9.48 g of white flaky crystals with a yield of 71% and a purity of 99% (GC)...

Embodiment 3

[0026] Preparation of 1,3 / 1,4-diethynylbenzene mixture

[0027] In 300ml of methanol, under stirring, slowly add 167.5g (2.99mol) potassium hydroxide, after completely dissolving, add 134g of 1,3-bis-alpha, beta-dibromoethyl obtained by step (1) in Example 1 The mixture of benzene and 1,4-bis-α,β-dibromoethylbenzene was heated and refluxed for 2 hours. At this time, a large amount of white solids were formed. TLC analysis showed that the reaction was complete, filtered, and the filter cake was washed with methanol to obtain white Solid, this is potassium bromide. Combine the washing liquid and the filtrate, distill to recover methanol, distill the residue with water steam, and pass hot water at 80°C in the condenser tube to obtain an emulsion of a mixture of 1,3-diethynylbenzene and 1,4-diethynylbenzene and water. Extracted with ether, distilled off the ether in the extract, and distilled the residue under reduced pressure, collected fractions at 65-80°C / 2mmHg to obtain 27.01...

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Abstract

Production of high-purity 1,4-diacetylene benzene is carried out by using industrial stage mixed divinylbenzene as raw material, liquid brominating, liquid-solid separating to obtain 1,4-bis-styrene dibromide, removing hydrogen bromide from 1,4-bis-styrene dibromide, and obtaining object. It achieves low cost, simple operation and high purity.

Description

technical field [0001] The invention relates to a preparation method of high-purity 1,4-diethynylbenzene. Background technique [0002] Aromatic acetylenic compounds are widely used in industry, and are often used to synthesize high-temperature resistant polymer materials, such as carbon / carbon composites. Carbon / carbon composite materials have excellent properties such as light weight, high temperature resistance, oxidation resistance, friction resistance, and large energy absorption, making them widely used in high-tech fields. It can also be used for high temperature resistant ablation materials, friction materials and biological materials. As a high temperature ablation material, it is usually used in an environment where high temperature is easy to oxidize. As a friction material, it can be used in the brake discs of aircraft and automobiles. The use of such materials can greatly reduce the weight of the aircraft itself and prolong its life. The braking performance is...

Claims

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): C07C5/00C07C15/48
Inventor 沈永嘉徐金峰黄发荣严连发
Owner EAST CHINA UNIV OF SCI & TECH
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