CN1252046C

CN1252046C - Method for preparing glycidyl methacrylate

Info

Publication number: CN1252046C
Application number: CN 200410027093
Authority: CN
Inventors: 张展洪; 张杰才
Original assignee: Individual
Current assignee: Individual
Priority date: 2004-05-09
Filing date: 2004-05-09
Publication date: 2006-04-19
Anticipated expiration: 2024-05-09
Also published as: CN1569823A

Abstract

The present invention relates to a preparation method for glycidyl methacrylate, which discloses a two-step preparation method that a, methacrylic acid and caustic alkali react in water so as to generate the alkali metal salt of the methacrylic acid; b, the alkali metal salt of the methacrylic acid reacts with epoxy chloropropane in the presence of polymerization inhibitors and tetramethylethylenediamine as a catalyst, and then crude products of the glycidyl methacrylate are obtained; after filtration, diethyl phthalate as a dehydrochlorination agent is added, and then fine products are obtained by reduced pressure distillation. The preparation method has the advantages of simple and easy raw material acquirement, low cost, moderate reaction, easy operation, low device requirement, low earlier stage investment in enterprise production, low production cost, high yield and high production purity.

Description

The manufacture method of glycidyl methacrylate

Technical field

The present invention relates to methacrylic acid or its esters is raw material, makes a kind of intramolecularly and contains carbon-carbon double bond, contains the method for the compound of epoxide group again.

Background technology

Glycidyl methacrylate (being called for short GMA), there is the manufacture method report of single stage method in past, it promptly is solvent with the epoxy chloropropane, methacrylic acid is a raw material, catalyzer is a yellow soda ash, emit heat because of yellow soda ash and methacrylic acid-respons, it is too fast to cause reacting liquid temperature to raise, and reactant is easily solidified.From and have the people further to study, invented the manufacture method of two step method, as the Chinese invention patent application number is 92106765.8 glycidyl methacrylate manufacture method and equipment, it discloses with methacrylic acid and an alkali metal salt in low mass molecule alcohol and high boiling solvent, in the presence of stopper, react, generate the methacrylic acid alkali metal salt, dry remove anhydrate and low mass molecule alcohol after, add epoxy chloropropane, phase-transfer catalyst, carry out esterification, obtain the GMA crude product, through rectifying tower refining formal product.More than this method, in first footwork, except methacrylic acid, an alkali metal salt, added stopper, can find out obviously that its reaction must be fierce, exothermic heat of reaction is very big, and add the stopper purpose is to reduce under too high temperature as far as possible, reactant very easily aggregates into the solid possibility, so operation easier is big.Next is that solvent is two-way choice, promptly selects low mass molecule alcohol, selects high boiling solvent again, and this just shows its complicacy, and operation easier is big.It is many to organize into composition separately, causes the cost height.Second footwork is the crude product ester that will obtain, and refining through the falling liquid film rectifying tower again, device category is various as can be seen, costs an arm and a leg, and it is excessive to have strengthened enterprise's early investment, has also caused the cost height of product.

Summary of the invention

The manufacture method that the purpose of this invention is to provide a kind of glycidyl methacrylate, its raw material are simple and easy to, and inexpensive, and reaction temperature and easy to operate, equipment requirements are not high, and the early investment that enterprise produces is few, and production cost is low, recovery rate and product purity height.

Technical solution of the present invention is as follows:

A, methacrylic acid, caustic alkali react in aqueous solvent, generate the methacrylic acid alkali metal salt;

B, methacrylic acid alkali metal salt, epoxy chloropropane are under stopper, catalyzer Tetramethyl Ethylene Diamine, consisting of phase-transferring agent existence condition, obtain the crude product of glycidyl methacrylate, again after filtration, the agent of adding dehydrochlorination, diethyl phthalate underpressure distillation go out the glycidyl methacrylate elaboration.

The above caustic alkali is that concentration is 50% the NaOH aqueous solution.

Among the A of the present invention, control reaction temperature is below 55 ℃ the time, and methacrylic acid is splashed in the NaOH solution water, and the methacrylic acid alkali metal salt that reaction generates is in oven dry below 60 ℃.

More than among the B of the present invention, stopper is a MEHQ, consisting of phase-transferring agent is a triethyl benzyl ammonia chloride.

Among the B of the present invention, temperature of reaction is controlled under 105 ℃～110 ℃ the condition, the methacrylic acid alkali metal salt, epoxy chloropropane, in the stopper MEHQ, the catalyzer Tetramethyl Ethylene Diamine, there is reaction down in the consisting of phase-transferring agent triethyl benzyl ammonia chloride, reactant removes by filter the salt of alkali metal chloride, filtrate goes out excessive epoxy chloropropane 80 ℃～90 ℃ underpressure distillation, then under stopper MEHQ existence condition, after adding dehydrochlorination agent diethyl phthalate, 100 ℃～105 ℃ of controlled temperature, underpressure distillation goes out the glycidyl methacrylate of purified water white transparency shape liquid under the 4Kpa condition.

Glycidyl methacrylate is a colourless transparent liquid, and is water insoluble, almost dissolves in all organic solvents.Because its intramolecularly had both contained carbon-carbon double bond, contained epoxide group again, can carry out differential responses respectively, be widely used in the synthetic and modification of macromolecular material, sensitive materials, medicine, tackiness agent, various fields such as coating.Resulting goods have good anti-ultraviolet, and are water-fast, heat-resisting, and characteristics such as anti-solvent are a kind of important fine chemical materials.Publish from the existing corresponding research method of 20th century the mid-1970s, until today, its synthesis technique is still being updated, the researchist mainly is the tackling key problem research from following problem, the one, select effective catalyst, the 2nd, optimize processing condition, the 3rd, improve product yield and purity.

GMA of the present invention synthetic be the heptane of changing over, hexane, ethanol, toluene as solvent, and adopt H ₂O is a solvent, and the methacrylic slow acid is splashed into the aqueous sodium hydroxide solution of 50% concentration, its reaction temperature and, cost of material is cheap and be easy to get.The sodium salt of methacrylic acid and the epoxy chloropropane that generate, at the catalyzer Tetramethyl Ethylene Diamine is esterification under the Primary Catalysts, the catalyzer that GMA adopts in the prior art is undesirable for the influence of speed of reaction, screen by repetition test, be chosen to be Tetramethyl Ethylene Diamine, Tetramethyl Ethylene Diamine has quickened speed of reaction, after reaction finishes, add the diethyl phthalate dehydrochlorination, selected diethyl phthalate is as the dehydrochlorination agent, this is because the GMA molecular weight is big, than great, boiling point is higher, be a kind of active polyfunctional group (two keys of being with, epoxide group) reactive monomer, heated time is long, the heating temperature height will cause crosslinking curing, then can't distill purification, so it is a kind of monomer that is difficult to separate purification.And suitably control distillation time, temperature, then hydrogenchloride is got rid of not thoroughly again, causes that purity is low, yield is low.The present invention is by multiple scheme, repetition test, agent of introducing dehydrochlorination and technology thereof have been invented, principle is that diethyl phthalate proportion is greater than 1.118, boiling point is up to 295 ℃, sinks to the reaction solution bottom after therefore adding reaction solution, becomes bedding course, reduce GMA and directly contacted drag and be heated, thereby controlled the rising of its temperature.The miscible drag that is co-located in diethyl phthalate of the hydrogenchloride of deviating from can not distill out.Moreover be diethyl phthalate boiling point height, originally the reaction distillation system is the epoxy chloropropane that contains in GMA, the tankage, be binary azeotropic, just become ternary azeotrope after now adding diethyl phthalate again, ternary azeotrope can reduce the vacuum distilling temperature, its benefit is that the hydrogenchloride that is sunken to drag can not be steamed, and reaches the purpose of dehydrochlorination and refined product.So the present invention can distill the 99%GMA product, its purity surpasses the manufacture method of prior art, reaches more than 99%.Be that prior art adopts the falling liquid film rectifying tower in addition, belong to being worth expensive device that we have only adopted common distillation plant, easy handling, easy to maintenance, cheap, reduced production cost significantly.

Advantage of the present invention be its raw material be simple and easy to and inexpensive, reaction temperature and easy to operate, equipment requirements are not high, the early investment that enterprise produces is few, production cost is low, recovery rate and product purity height.

Embodiment

Manufacture method of the present invention divided for two steps carried out

The preparation of A, sodium salt of methacrylic acid:

Stirring, reflux exchanger are being housed, and temperature is taken into account in the four-hole bottle of dropping funnel, adds 80ml water, adds 102 gram concentration again and be 50% through being cooled to the NaOH aqueous solution of normal temperature, after stirring, splashes into the 100ml methacrylic acid lentamente.Control reaction temperature is below 55 ℃, after dropwising, continues to stir after 1 hour, the soup compound in the flask is released in the Stainless Steel Disc, then in baking oven inner control temperature in oven dry below 60 ℃, promptly obtain sodium salt of methacrylic acid.

B, GMA synthesis technique:

In the there-necked flask that agitator, reflux condensation mode water trap and thermometer are housed, add 80g exsiccant sodium salt of methacrylic acid, 0.4g stopper MEHQ, catalyzer Tetramethyl Ethylene Diamine 1.5g, consisting of phase-transferring agent triethyl benzyl ammonia chloride 1g, epoxy chloropropane 500g stirs the reaction of heating.Control reaction temperature was reacted 3 hours at 105 ℃～110 ℃, and the cooling cooling removes by filter NaCl, and filtrate is distilled out excessive epoxy chloropropane 80 ℃～90 ℃ reduced vacuum.And then add 0.2g stopper MEHQ and the agent of 20g diethyl phthalate dehydrochlorination, and underpressure distillation goes out the GMA finished product under 100 ℃～105 ℃ 4Kpa conditions again, and the GMA finished product is a colourless transparent liquid.

Claims

1, the manufacture method of glycidyl methacrylate is characterized in that

B, methacrylic acid alkali metal salt, epoxy chloropropane are under stopper, catalyzer Tetramethyl Ethylene Diamine, consisting of phase-transferring agent existence condition, obtain the crude product of glycidyl methacrylate, again after filtration, add the underpressure distillation of dehydrochlorination agent diethyl phthalate and go out the glycidyl methacrylate elaboration.

2, the manufacture method of glycidyl methacrylate according to claim 1 is characterized in that caustic alkali is that concentration is 50% the NaOH aqueous solution.

3, the manufacture method of glycidyl methacrylate according to claim 1 and 2 is characterized in that in control reaction temperature be below 55 ℃ the time, and methacrylic acid is splashed into NaOH and H ₂In the O solution, the methacrylic acid alkali metal salt that reaction generates is in oven dry below 60 ℃.

4, the manufacture method of glycidyl methacrylate according to claim 1 is characterized in that stopper is a MEHQ, and consisting of phase-transferring agent is a triethyl benzyl ammonia chloride.

5, manufacture method according to claim 1 or 4 described glycidyl methacrylate, it is characterized in that control reaction temperature is under 105 ℃～110 ℃ condition, the methacrylic acid alkali metal salt, epoxy chloropropane, in the stopper MEHQ, the catalyzer Tetramethyl Ethylene Diamine, there is reaction down in the consisting of phase-transferring agent triethyl benzyl ammonia chloride, reactant removes by filter the salt of alkali metal chloride, filtrate goes out excessive epoxy chloropropane 80 ℃～90 ℃ underpressure distillation, then under stopper MEHQ existence condition, after adding dehydrochlorination agent diethyl phthalate again, 100 ℃～105 ℃ of controlled temperature, underpressure distillation goes out the glycidyl methacrylate of the water white transparency shape liquid of elaboration under the 4Kpa condition.