CA2002977A1 - Process for the preparation of epoxy compounds - Google Patents
Process for the preparation of epoxy compoundsInfo
- Publication number
- CA2002977A1 CA2002977A1 CA002002977A CA2002977A CA2002977A1 CA 2002977 A1 CA2002977 A1 CA 2002977A1 CA 002002977 A CA002002977 A CA 002002977A CA 2002977 A CA2002977 A CA 2002977A CA 2002977 A1 CA2002977 A1 CA 2002977A1
- Authority
- CA
- Canada
- Prior art keywords
- process according
- aromatic
- hydrogen
- added
- approximately
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G59/00—Polycondensates containing more than one epoxy group per molecule; Macromolecules obtained by polymerising compounds containing more than one epoxy group per molecule using curing agents or catalysts which react with the epoxy groups
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D301/00—Preparation of oxiranes
- C07D301/02—Synthesis of the oxirane ring
- C07D301/03—Synthesis of the oxirane ring by oxidation of unsaturated compounds, or of mixtures of unsaturated and saturated compounds
- C07D301/14—Synthesis of the oxirane ring by oxidation of unsaturated compounds, or of mixtures of unsaturated and saturated compounds with organic peracids, or salts, anhydrides or esters thereof
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D303/00—Compounds containing three-membered rings having one oxygen atom as the only ring hetero atom
- C07D303/02—Compounds containing oxirane rings
- C07D303/12—Compounds containing oxirane rings with hydrocarbon radicals, substituted by singly or doubly bound oxygen atoms
- C07D303/18—Compounds containing oxirane rings with hydrocarbon radicals, substituted by singly or doubly bound oxygen atoms by etherified hydroxyl radicals
- C07D303/20—Ethers with hydroxy compounds containing no oxirane rings
- C07D303/24—Ethers with hydroxy compounds containing no oxirane rings with polyhydroxy compounds
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F8/00—Chemical modification by after-treatment
- C08F8/08—Epoxidation
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G59/00—Polycondensates containing more than one epoxy group per molecule; Macromolecules obtained by polymerising compounds containing more than one epoxy group per molecule using curing agents or catalysts which react with the epoxy groups
- C08G59/02—Polycondensates containing more than one epoxy group per molecule
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- General Chemical & Material Sciences (AREA)
- Epoxy Compounds (AREA)
- Heterocyclic Compounds That Contain Two Or More Ring Oxygen Atoms (AREA)
- Epoxy Resins (AREA)
Abstract
K-17325/=
A process for the preparation of epoxy compounds Abstract A process for the preparation of epoxy compounds by epoxidising aromatic allyl ethers with dioxiranes. Epoxy resins with high epoxy values and a low halogen content can be produced in high yields with this process.
A process for the preparation of epoxy compounds Abstract A process for the preparation of epoxy compounds by epoxidising aromatic allyl ethers with dioxiranes. Epoxy resins with high epoxy values and a low halogen content can be produced in high yields with this process.
Description
K-17325/=
A process ~r the pr~para~ioll of epoxy ~ompounds The present invention relates to an improved process for the preparation of epoxy com-pounds, and to the manufacture of cured products from these compounds.
Epoxy resins have for a long time been employed, inter alia, in the electronics industry.
In recent years there has been a steady increase in the purity requirements for such resins.
In par~icular, small amounts of ionic or hydrolysable halogen may have a detrimental ef-fect. Also, there is an increasing demand for resins with as high as poss;ble a degree of epoxidation. Epoxy resins are generally prepared by reacting compounds having reactive hydrogen atoms, preferably phenols, with epichlorohydrin. For the preparation of resins with a low halogen content there are also known processes in which compounds having ethylenically unsaturated bonds are epoxidised. Normally, in the case of allyl com-pounds, such compounds are aromatic C-allyl compounds, which are epoxidised withperacids, for example peracetic acid. Examples of such reactions can be found inEP-A-205,402.
The epoxidation of ethylenically unsaturated compounds with dimethyldioxirane offormula I is known per se.
CHX¦
For example, in J. Org. Chem., 51, 1925-6 (1986) P.F.Corey et aL describe the reaction of -unsaturated carboxylic acids, inter alia cinnamic acid, with dimethyldioxirane. Also, in 3. Org. Chem., 47, 2670-3 (1982) G. Cicala et ah describe the reaction of aliphatic allyl alcohols with dimethyldioxirane as epoxidising reagent.
The epoxidation of aromatic allyl ethers with peracids is described, for example, in 2~
U~-A-3,957,873. This reaction has proved as a rule to give only moderate yields and epoxy contents. Furthermore, the use of peracids in large scale industrial processes represents a safety risk.
It has now surprisingly been found that high yields and high epoxy contents can be ob-tained in the epoxidation of aromatic allyl ethers if the reaction is c~ried out with di-oxiranes. Furtherrnore, the safety risk in such epoxidations can be reduced in comparison with epoxidation using peracids.
The present invention relates to a process for the preparation of epoxy compounds from aromatic allyl ethers having at least one radical of formula II
Rl O ~ R2 (II), bonded directly to the aromatic nucleus, in which each of Rl, R2 and R3, independently of the others, is hydrogen or Cl- C6alkyl, especially methyl and, more especially, hydrogen, which comprises epoxidising the starting material, as such or dissolved in an inert solvent, with a dioxirane, approximately from 1 to 20 mols of clioxirane being used per allyl group.
Preferred aromatic allyl ethers for use in the process of the invention include compounds of formula III or compounds that consist essentially of recurring structural units of formula IV or V
Rl R2 I Rl ~E~3 A- L ~3 R2 ~ 6 }n 2~7 --~--CH~ CH2~_ R3 Rl (V), ~/~=<
in which m is 1, 2, 3 or 4, n is an integer of from 2 to 12; p is an integer of from 2 to 100, q is 0, 1, 2 or 3, R1, R;~ and R3 are as defined above, R4 is Cl-C5alkyl or halogen, Rs and R6 are each independently hydrogen or Cl-C6alkyl and A is a m-valent aromatic radical of a phenol after removal of the hydroxy groups.
Any radicals representing Cl-C6alkyl are branched or preferably straight-chain alkyl radicals. Examples are methyl, ethyl, n-propyl, isopropyl, n-butyl, sec.-bu~yl, tert.-butyl, n-pentyl or n-hexyl.
Ethyl, n-propyl or n-butyl, but especially methyl, is preterred.
Tlle index m is preferably 2. The index n is preferably from 3 to 6 and the index p is pre-ferably from 5 to 40. The index q is preferably 1 and more especially 0. R4 as halogen is usually chlorine or bromine.
Examples of preferred compounds from which the allyl ethers used in the process of the invention are derived are mono- or poly-nuclear monophenols, such as phenol, cresols or chlorophenol, or especially mono- or poly-nuclear polyphenols, such as resorcinol, hydro-quinone, bis-(hydroxyphenyl)-methane (bisphenol F), 2,2-bis-(4-hydroxyphenyl)-prop.me (bisphenol A), brominated 2,2-bis-(4-hydroxyphenyl)-propane, bis-(4-hydroxyphenyl)-ether, bis-(4-hydroxyphenyl)-sulfone, 1,3,5-trihydroxybenzene, 1,1,2,2-tetrakis-~4-hydroxyphenyl)-ethane, novolaks, which can be obtained by condensing aldehydes, such as formaldehyde, acetaldehyde, chloral or furfuraldehyde, with unsubstituted or alkyl- or halogen-substituted phenols, such as phenol, the above-described bisphenols, 2- or 4-methylphenol, 4-tert.-butylphenol, p-nonylphenol or 4-chlorophenol, or polyvinyl-phenols, such as poly-p-vinylphenol.
The allyl ether starting materials can be prepared in a manner known ~ se from these mono- or poly-phenols by etherification with an allyl halide, especially allyl chloride.
Preferred starting materials are compounds of formula III, IV or V in which Rl and R2 are hydrogen and ~3 is methyl or, especially, hydrogen.
More especially preferred starting materials are compounds of formula III, IV or V in which rn is 2, n is from 3 to 6, p is from 5 to 40, q is 0, A is a dinuclear radical of a bis-phenol and Rl, R2 and R3 are hydrogen.
Either the starting material can be epoxidised with a solution of a dioxirane in a ketone, or the dioxirane is prepared in situ in the reaction mixture with the starting material.
The preparation of dioxirane solutions is known ~ se and is described, for example, by W. Adam et ah in J. Org. Chem., ~2, 2800-3 (19~7) and by R. Mello in J. Org. Chem., 53, 3890-1 (1988). ~or this purpose a peroxomonosulfate, for example potassium peroxo-monosulfate, is added to a solution of a lcetone, especially an aliphatic ketone, such as ace~one, hexafluoroacetone, methyl ethyl ketone or cyclohexanone, which has been ad-justed with a buffer to a pH value of approximately from 6 to l0, especially from 6 to 8.
The resulting dioxirane can, if desired, be concentrated. The solution can be used as such directly for the epoxidation, or can be stored for some time with cooling. The peroxo-monosulfates used may be, for example, the alkali metal salts of peroxomonosulfuric acid (Caro's acid), such as the sodium or potassium salts. F or example it is possible to use for this purpose the product Oxone(~ produced by Du Pont. This is a mixture of potassium peroxomonosulfate with potassium sulfate and potassium hydrogen sulfate.
The epoxidation of aromatic allyl ethers with dioxirane solutions can be carried out, for example, as follows:
The starting material is introduced into a vessel as such or in a solvent that is inert under the reaction conditions, and the dioxirane solution in the respective ketone is added.
Generally, approximately from one to twenty mols of dioxirane is used per mol of double bond to be epoxidised. The addition of the dioxirane solution and the subsequent reac-tion can be carried out with cooling or with heating of the reaction mixture to reflux.
Depending on the reactivity of the reactants and the temperatures employed, the epoxida-tion normally takes from 0.5 to 24 hours.
'7~
The epoxidation of the arornatic allyl ether, in which the dioxirane is produced in situ in the reaction mixture with the starting material, may be carried out, for example, as follows:
The starting material is introduced as such, or in a solvent that is inert under the reaction conditions, into a vessel together with a phase transfer catalyst and in conjunction with a ketone, especially an aliphatic ketone, such as acetone, hexafluoroacetone, methyl ethyl ketone or cyclohexanone, and water, so that a two-phase system results. The aqueous phase contains a buffer for establishing the pH value in a range of approximately from 6 to 10, especially from 6 to 8. Subsequently a peroxomonosulfate, for example Oxone~', is added. The amount of peroxomonosulfate is generally approximately from one to ten mols per mol of double bond to be epoxidised. The peroxomonosulfate can be added in solid form or dissolved in buffered water (pH value approximately from 6 to 10, depend-ing on the pH value in the two-phase system). It is advisable to monitor the pH value of the reaction rnixture during the addition and keep it constant, if necessary by the addition of a base, such as sodium hydroxide solution or potassium hyclroxide solution. Depend-ing on the reactivity of the reactants and the temperatures employed, the epoxidation normally takes from 0.5 to 24 hours.
In this variant it is possible to use any phase transfer catalyst that is known ~ se. There are especially used crown ethers, such as 18-crown-6, or quaternary ammonium or phos-phonium salts, such as tetrabutylammollium hyclrogell sulfate or tetrabutylphosphonium hydrogen sulfate.
~ny buffer customary per se may be used as buffer solution. It is preferable to use pilOS-phate buffers with which a pH value of approximately 7 is established.
Solvents for the starting material that are inert under the reaction conditions are, for example, ~romatic hydrocarbons, which may optionally be halogenated, such as benzene, toluene, xylenes, cumene, chlorobenzene or dichlorobenzene, or halogenated aliphatic hydrocarbons, such as trichloroethane, tetrachloroethane, dichloromethane or chloro-fonn, or esters, such as, for example, ethyl acetate.
The process of the invention can be carried out in air or under a protective gas, for example nitrogen or argon.
Reaction temperatures of from 0 to 30C are preferred.
Especially preferred epoxidation reagents are bis-trifluoromethyldioxirane or, especially, dimethyldioxirane.
In an especially preferred form of the process of the invention the aromatic allyl ether is purified before the epoxidation step, for example by chromatography ~r, especially, by distillation; higher-molecular-weight starting materials can be purified by thin-layer or flash distillation. This process variant generally results in especially high yields and epoxy values.
In another especially preferred form of the process of the invention, the epoxidation is carried out in the manner described above in a two-phase system containing an aromatic allyl ether, dissolved in an inert solvent, and an aqueous ketone phase, and the dioxirane is produced in situ in the reaction mixture, the peroxomonosulfate being added in solid forrn and the pH value being held constant by the addition of an aqueous solution of a base, especially sodium hydroxide solution.
In this form of the process the pH value is preferably from 6.5 to 7.5, the aromatic allyl ether is placed in a vessel in an inert solvent together with a crown ether or a quaternary ammonium salt as phase transfer catalyst, and the ketone used is acetone.
The resins obtainable in accordance with the invention can be cured in a manner custom-ary ~ se by adding a curing agent, for example a primary or secondary polyamine, an anhydride of a polycarboxylic acid or o a catalytically-acting curing agent, such as a tertiary amine, and if appropriate heating the cornposition. The cured products are distinguished especially by a low halogen content.
The invention relates also to a process for the manufacture of cured producLs which com-prises curing the epoxy resins obtainable in accordance with the process of the invention by the addition of a curing agent known ~ se and, if appropriate, heating.
The curable mixtures can, if desired, contain further additives customary ~ se, such as reactive diluents, plasticisers, extenders, fillers and reinforcing agents, for example coaltar, bitumen, textile fibres, glass fibres, carbon fibres, mineral silicates, mica, quartz powder, aluminium oxide hydrate, bentonite, wollastonite, kaolin, silicic acid aerogel or 2~ 97~7 metal powders7 such as aluminium powder or iron powder, and also pigments and dye-stuffs, such as carbon black, oxide dyes and titanium dioxide, and also flame-proofing agents, thixotropic agents, flOw agents (some of which can also be used as mould release agents), such as silicones, waxes and stearates, or adhesion promoters, antioxidants and light stabilisers.
The mixtures of the invention can be used very generally for the manufacture of cured products and can be employed in a formulation adapted to the respective specific field of application, in unfilled or filled state as a component of paint compositions, coating com-positions, lacquers, moulding compositions, dipping resins, whirl sintering powders, in-jection moulding folmulations, tool resins, powder lacquers, casting resins, impregnating resins, laminating resins, adhesives or matrix resins.
The resins obtainable in accordance with the invention are suitable, for example, for use in the fields of surface protection, laminating processes, in construction and especially in electrotechnology and electronics. Compounds with an average of one epoxy group can be used as reactive diluents.
Examples ~: Prepar~tioll of bisph~nol A-di~lycidyl ~ther 50 g (0.08 mol) of solid Oxone(~ are added over a period of three and a half hours at room temperature, with vigorous stirring, to 15.4 g (0.05 mol~ of distilled bisphenol A-diallyl ether (prepared according to DE-A-26 27 045) and 0.66 g of 18-crown-6 in a two-phase system of 50 ml of acetone, 50 ml of dichloromethane and 100 ml of phosphate buffer pH
7.0, the pH being held constant with 15 % NaOH solution. After a further 15 minutes, the phases are separated, 10 ml of acetone, 5 ml of dichloromethane, 100 ml of phosphate.
buffer pH 7.0 and 0.66 g of 1 8-crown-6 are added to the organic phase and, over a period of three and a half hours, a further 50 g (0.08 mol) of solid Oxone(~) is added. After 15 minutes the phases are separated again and the above- described operations are repeated, 30 g (0.05 mol) of Oxone(g) being used. The reaction mixture is then extracted twice with 100 ml of toluene each time, and the combined organic phases are concentrated to 200 ml using a rotary evaporator. The toluene phase is washed three times with 50 ml of lN
NaOH solution each time and five times with 50 ml of water each time, dried overMgSO4, filtered and concentrated by evaporation. 13.6 g (80 %) of a golden yellow liquid having the following properties are obtained:
l~poxy number: 5.11 val/kg (87 %); l125:3730 mPa.s total chlorine content: 425 ppm; hydrolysable chlorine content: 128 ppm.
Example 2: Preparation of bisphenol A-di~yci(lyl ether 87 ml of a 0.1M solution of dimethyldioxirane in acetone [prepared according to W. Adam et al., J. Org. Chem., 52, 2800-3 (1987)] are added at room temperature, under a nitrogen atmosphere, to 0.31 g (1 mmol) of distilled bisphenol A-diallyl ether and stirred for six hours. The solvent and the excess dimethyldioxirane are then distilled off using a rotary evaporator. 0.33 ~ (97 %) of a faintly yellow, clear liquid with an epoxy number of 4.8 val/kg (82 %) is obtained.
Example 3: Preparation of bisphenol A-di-(2,3-epoxybutyl) ether 23 g (0.04 mol) of Oxone(~ dissolved in 100 ml of phosphate buffer pH 7.0 are added dropwise at room temperature, over a period of one and a quarter hours, to 3.36 g (0.01 mol) of distilled bisphenol A-dicrotyl ether (prepared analogously to the diallyl ether according to DE-A-26 27 045) and 0.6 g of 18-crown-6 in a two-phase system of 50 ml of acetone,50 ml of dichloromethane and 50 ml of phosphate buffer pH 7.0, the pH being held constant with 15 % NaOH solution. Subsequently the reaction mixture is stirred for a further one and a half hours and then extracted twice with 100 ml of dichloromethane each time. The combined organic phases are washed t~ice with 50 ml of water eachtime, rendered free of peroxide over sodium sulfite, dried over MgSO4, filtered and con-centrated by evaporation. 3.5 g (95 %) of a clear, light- brown liquid having an epoxy number of 5.05 val/kg (93 %) are obtained.
Example 4: Preparation of bisphenol A~di-(2,3-epoxybutyl) ether 33 ml of a 0.15M solution of dimethyldioxirane in acetone are added at room temperature, under a nitrogen atmosphere, to 0.17 g (0.5 mmol) of distilled bisphenol ~-dicrotyl ether and stirred ~or one and three qu~rter hours. The solvent and the excess dimethyldiox*ane are then distilled off in a rotary evaporator. 0.17 g (92 %) of a faintly yeliow, clear liquid having an epoxy number of 4.9 val/kg (91 %) is obtained.
Example 5: P~epar~tion of poly-4-(2,3-epoxyblltoxy)-styrene a) Preparation of poly-4-(2,3-butenoxy)-styrene.
107.7 g of K2CO3 are added over a period of 10 minutes at room temperature, with stir-ring, to a solution of 60.1 g of Resin(~) M (poly-p-vinylphenol; Maruzen Oil) and 128.3 g of crotyl chloride in 300 ml of l:)MSO and the reaction mixture is then stirred for four and a half hours at 60C. The reaction mixture is then cooled, 300 ml of water are added and extraction is carried out three times with 100 ml of ethyl acetate each time. The combined organic phases are washed three times with 100 ml of water each time, dried overMgSO4, filtered and concentrated by evaporation. 82.8 g (95 %) of a brown resin are ob-tained. l112~ = 1560 mPa.s.
b~ Preparation of poly-4-(2,3-epoxybutoxy)-styrene.
90 g (0.15 mol) of Oxone~ are added over a period of three and a quarter hours at room temperature, with vigorous stirring, to 8.7 g of the polycrotyl ether of Example Sa) and 0.6 g of 18-crown-6 in a two-phase system of 50 ml of acetone, 50 ml of dichloromethane and 10û ml of phosphate buffer pH 7.0, the pH value being held constant with 15 %
NaOH solution. The suspension is then stirred for a further hour and subsequently filtered. The filtrate is extracted three times with 100 ml of methyl ethyl ketone each time, the combined organic phases are washed twice with 100 ml of saturated NaClsolution each time, tested for peroxides with KI-starch paper, dried over MgSO4, filtered and concentrated by evaporation. 9.0 g (95 %) of a brown resin are obtained.
60 = 780 mPa.s; epoxy number = 4.97 val/kg (95 %).
Example 6: Prepar~tion of bisphcnol F-di~lycidyl ether 100.1 g (0.5 mol) of bisphenol F and 133.9 g (1~75 mol) of allyl chloride are introduced into 250 ml of DMSO, and 207.3 g (1.5 mol) of K2CO3 are added in portions over aperiod of one hour. The mixture is then heated to 60C and stirred for four hours at that ~emperature. The reaction mixture is subsequently cooled, poured onto 750 ml of water and ext~acted three times with dichloromelhane. The combined organic phases are washed three times with water, toluene is added and the whole is concen~rated by eva-poration. 132 g of bisphenol F-diallyl ether are obtained in the forrn of a brown liquid. A
portion of this is distilled at 185C/1.3 Pa in a thin-layer evaporator. 14 g (0.05 mol) of the distilled product are dissolved in a two-phase system of 50 ml of acetone,50 ml of di-chloromethane and 100 ml of phosphate buffer pH = 7.0, and 0.66 g (2.5 rnmol) of18-crown-6 are added. Over a period of three and a half hours 60 g (95 mmol) of Oxone~) are then added in portions at room temperature, the pH vallle being held constant with 15 % NaOH. The phases are then separated, 30 ml of acetone, 5 ml of dichloro-methane, 100 ml of phosphate buffer pH value 7.0 and 0.66 g (2.5 mmol) of 18-crown-6 are added to the organic phase, and, over a period of three and a half hours, a further 60 g - lo -(95 mmol) of Oxone(~) is added, with the pH value being held constant. The reaction mix-ture is then diluted with water and extracted three times with dichloromethane. The combined organic phases are washed once with lN NaOH and four times with water, dried over MgSO4, filtered and concentrated by evaporation. 12.6 g of bisphenol F-diglycidyl ether are obtained in the forrn of a clear brown liquid having an epoxy content of 4.42 val/kg (75 %).
Exarnple 7: Preparation of a glycidyl ether of a cresol/formal(lehyde novolak 100 g (û.7 mol) of a cresol/formaldehyde novolak (Mn = 624; Mw = 906) and 11.8 g(0.035 mol) of tetrabutylammonium hydrogen sulfate are dissolved in 160.7 g (2.1 mol) of allyl chloride at 30C, and then 1~0 g (3.5 mol) of NaOH are added in portions over a period of one hour. The mixture is then heated to reflux and stirred for two hours at that temperature. The reaction mixture is cooled, water is added, and extraction is carried out three times with methyl ethyl ketone. The combined organic phases are washed three times with 10 % N~14CI solution and twice with water, dried over MgSO4, filtered and concentrated by evaporation. 126 g of the polyallyl ether of the cresol/formaldehyde novolak are obtained in the forrn of a dark-violet highly viscous resin. 50 g of this crude product are dissolved in as small a quantity as possible of ethyl acetate and filtered with hexane/ethyl acetate = 1:1 through a 20 cm long silica gel column (diameter 10 cm). 45 g of a light-yellow highly viscous resin are obtained. 19.1 g (û.1 mol) of the purifiedpro-duct are dissolved in a two-phase system of 50 ml of acetonc, 50 ml of dichloromethane and 100 ml of phosphate buffer pH = 7.0, and 0.66 g (2.5 mmol) of 18-crown-6 is added.
60 g (95 mmol) of Oxone~ are then added in portions at room temperature over a period of three and a half hours, the pH value being held constant with 15 % NaOH. The phases are then separated, 20 ml of acetone, 10 ml of dichloromethane, 5û ml of phosphate buffer pH value 7.0 and 0.66 g (2.5 mmol) of 18-crown-6 are added to the organic phase, and a ~urther 60 g (95 mmol) of Oxone(~ is added in portions over a period of three and a half hours with the pH value being held constant. The reaction mixture is then diluted with water and extracted three times with ethyl acetate. The combined organic phases are washed once with lN NaOH and three times with water, toluene is added and the whole is concentrated by evaporation. 12 g of the polyglycidyl ether of the cresol/formaldehyde novolak are obtained in the form of a brown solid with an epoxy content of 3.94 val/kg (82 %)
A process ~r the pr~para~ioll of epoxy ~ompounds The present invention relates to an improved process for the preparation of epoxy com-pounds, and to the manufacture of cured products from these compounds.
Epoxy resins have for a long time been employed, inter alia, in the electronics industry.
In recent years there has been a steady increase in the purity requirements for such resins.
In par~icular, small amounts of ionic or hydrolysable halogen may have a detrimental ef-fect. Also, there is an increasing demand for resins with as high as poss;ble a degree of epoxidation. Epoxy resins are generally prepared by reacting compounds having reactive hydrogen atoms, preferably phenols, with epichlorohydrin. For the preparation of resins with a low halogen content there are also known processes in which compounds having ethylenically unsaturated bonds are epoxidised. Normally, in the case of allyl com-pounds, such compounds are aromatic C-allyl compounds, which are epoxidised withperacids, for example peracetic acid. Examples of such reactions can be found inEP-A-205,402.
The epoxidation of ethylenically unsaturated compounds with dimethyldioxirane offormula I is known per se.
CHX¦
For example, in J. Org. Chem., 51, 1925-6 (1986) P.F.Corey et aL describe the reaction of -unsaturated carboxylic acids, inter alia cinnamic acid, with dimethyldioxirane. Also, in 3. Org. Chem., 47, 2670-3 (1982) G. Cicala et ah describe the reaction of aliphatic allyl alcohols with dimethyldioxirane as epoxidising reagent.
The epoxidation of aromatic allyl ethers with peracids is described, for example, in 2~
U~-A-3,957,873. This reaction has proved as a rule to give only moderate yields and epoxy contents. Furthermore, the use of peracids in large scale industrial processes represents a safety risk.
It has now surprisingly been found that high yields and high epoxy contents can be ob-tained in the epoxidation of aromatic allyl ethers if the reaction is c~ried out with di-oxiranes. Furtherrnore, the safety risk in such epoxidations can be reduced in comparison with epoxidation using peracids.
The present invention relates to a process for the preparation of epoxy compounds from aromatic allyl ethers having at least one radical of formula II
Rl O ~ R2 (II), bonded directly to the aromatic nucleus, in which each of Rl, R2 and R3, independently of the others, is hydrogen or Cl- C6alkyl, especially methyl and, more especially, hydrogen, which comprises epoxidising the starting material, as such or dissolved in an inert solvent, with a dioxirane, approximately from 1 to 20 mols of clioxirane being used per allyl group.
Preferred aromatic allyl ethers for use in the process of the invention include compounds of formula III or compounds that consist essentially of recurring structural units of formula IV or V
Rl R2 I Rl ~E~3 A- L ~3 R2 ~ 6 }n 2~7 --~--CH~ CH2~_ R3 Rl (V), ~/~=<
in which m is 1, 2, 3 or 4, n is an integer of from 2 to 12; p is an integer of from 2 to 100, q is 0, 1, 2 or 3, R1, R;~ and R3 are as defined above, R4 is Cl-C5alkyl or halogen, Rs and R6 are each independently hydrogen or Cl-C6alkyl and A is a m-valent aromatic radical of a phenol after removal of the hydroxy groups.
Any radicals representing Cl-C6alkyl are branched or preferably straight-chain alkyl radicals. Examples are methyl, ethyl, n-propyl, isopropyl, n-butyl, sec.-bu~yl, tert.-butyl, n-pentyl or n-hexyl.
Ethyl, n-propyl or n-butyl, but especially methyl, is preterred.
Tlle index m is preferably 2. The index n is preferably from 3 to 6 and the index p is pre-ferably from 5 to 40. The index q is preferably 1 and more especially 0. R4 as halogen is usually chlorine or bromine.
Examples of preferred compounds from which the allyl ethers used in the process of the invention are derived are mono- or poly-nuclear monophenols, such as phenol, cresols or chlorophenol, or especially mono- or poly-nuclear polyphenols, such as resorcinol, hydro-quinone, bis-(hydroxyphenyl)-methane (bisphenol F), 2,2-bis-(4-hydroxyphenyl)-prop.me (bisphenol A), brominated 2,2-bis-(4-hydroxyphenyl)-propane, bis-(4-hydroxyphenyl)-ether, bis-(4-hydroxyphenyl)-sulfone, 1,3,5-trihydroxybenzene, 1,1,2,2-tetrakis-~4-hydroxyphenyl)-ethane, novolaks, which can be obtained by condensing aldehydes, such as formaldehyde, acetaldehyde, chloral or furfuraldehyde, with unsubstituted or alkyl- or halogen-substituted phenols, such as phenol, the above-described bisphenols, 2- or 4-methylphenol, 4-tert.-butylphenol, p-nonylphenol or 4-chlorophenol, or polyvinyl-phenols, such as poly-p-vinylphenol.
The allyl ether starting materials can be prepared in a manner known ~ se from these mono- or poly-phenols by etherification with an allyl halide, especially allyl chloride.
Preferred starting materials are compounds of formula III, IV or V in which Rl and R2 are hydrogen and ~3 is methyl or, especially, hydrogen.
More especially preferred starting materials are compounds of formula III, IV or V in which rn is 2, n is from 3 to 6, p is from 5 to 40, q is 0, A is a dinuclear radical of a bis-phenol and Rl, R2 and R3 are hydrogen.
Either the starting material can be epoxidised with a solution of a dioxirane in a ketone, or the dioxirane is prepared in situ in the reaction mixture with the starting material.
The preparation of dioxirane solutions is known ~ se and is described, for example, by W. Adam et ah in J. Org. Chem., ~2, 2800-3 (19~7) and by R. Mello in J. Org. Chem., 53, 3890-1 (1988). ~or this purpose a peroxomonosulfate, for example potassium peroxo-monosulfate, is added to a solution of a lcetone, especially an aliphatic ketone, such as ace~one, hexafluoroacetone, methyl ethyl ketone or cyclohexanone, which has been ad-justed with a buffer to a pH value of approximately from 6 to l0, especially from 6 to 8.
The resulting dioxirane can, if desired, be concentrated. The solution can be used as such directly for the epoxidation, or can be stored for some time with cooling. The peroxo-monosulfates used may be, for example, the alkali metal salts of peroxomonosulfuric acid (Caro's acid), such as the sodium or potassium salts. F or example it is possible to use for this purpose the product Oxone(~ produced by Du Pont. This is a mixture of potassium peroxomonosulfate with potassium sulfate and potassium hydrogen sulfate.
The epoxidation of aromatic allyl ethers with dioxirane solutions can be carried out, for example, as follows:
The starting material is introduced into a vessel as such or in a solvent that is inert under the reaction conditions, and the dioxirane solution in the respective ketone is added.
Generally, approximately from one to twenty mols of dioxirane is used per mol of double bond to be epoxidised. The addition of the dioxirane solution and the subsequent reac-tion can be carried out with cooling or with heating of the reaction mixture to reflux.
Depending on the reactivity of the reactants and the temperatures employed, the epoxida-tion normally takes from 0.5 to 24 hours.
'7~
The epoxidation of the arornatic allyl ether, in which the dioxirane is produced in situ in the reaction mixture with the starting material, may be carried out, for example, as follows:
The starting material is introduced as such, or in a solvent that is inert under the reaction conditions, into a vessel together with a phase transfer catalyst and in conjunction with a ketone, especially an aliphatic ketone, such as acetone, hexafluoroacetone, methyl ethyl ketone or cyclohexanone, and water, so that a two-phase system results. The aqueous phase contains a buffer for establishing the pH value in a range of approximately from 6 to 10, especially from 6 to 8. Subsequently a peroxomonosulfate, for example Oxone~', is added. The amount of peroxomonosulfate is generally approximately from one to ten mols per mol of double bond to be epoxidised. The peroxomonosulfate can be added in solid form or dissolved in buffered water (pH value approximately from 6 to 10, depend-ing on the pH value in the two-phase system). It is advisable to monitor the pH value of the reaction rnixture during the addition and keep it constant, if necessary by the addition of a base, such as sodium hydroxide solution or potassium hyclroxide solution. Depend-ing on the reactivity of the reactants and the temperatures employed, the epoxidation normally takes from 0.5 to 24 hours.
In this variant it is possible to use any phase transfer catalyst that is known ~ se. There are especially used crown ethers, such as 18-crown-6, or quaternary ammonium or phos-phonium salts, such as tetrabutylammollium hyclrogell sulfate or tetrabutylphosphonium hydrogen sulfate.
~ny buffer customary per se may be used as buffer solution. It is preferable to use pilOS-phate buffers with which a pH value of approximately 7 is established.
Solvents for the starting material that are inert under the reaction conditions are, for example, ~romatic hydrocarbons, which may optionally be halogenated, such as benzene, toluene, xylenes, cumene, chlorobenzene or dichlorobenzene, or halogenated aliphatic hydrocarbons, such as trichloroethane, tetrachloroethane, dichloromethane or chloro-fonn, or esters, such as, for example, ethyl acetate.
The process of the invention can be carried out in air or under a protective gas, for example nitrogen or argon.
Reaction temperatures of from 0 to 30C are preferred.
Especially preferred epoxidation reagents are bis-trifluoromethyldioxirane or, especially, dimethyldioxirane.
In an especially preferred form of the process of the invention the aromatic allyl ether is purified before the epoxidation step, for example by chromatography ~r, especially, by distillation; higher-molecular-weight starting materials can be purified by thin-layer or flash distillation. This process variant generally results in especially high yields and epoxy values.
In another especially preferred form of the process of the invention, the epoxidation is carried out in the manner described above in a two-phase system containing an aromatic allyl ether, dissolved in an inert solvent, and an aqueous ketone phase, and the dioxirane is produced in situ in the reaction mixture, the peroxomonosulfate being added in solid forrn and the pH value being held constant by the addition of an aqueous solution of a base, especially sodium hydroxide solution.
In this form of the process the pH value is preferably from 6.5 to 7.5, the aromatic allyl ether is placed in a vessel in an inert solvent together with a crown ether or a quaternary ammonium salt as phase transfer catalyst, and the ketone used is acetone.
The resins obtainable in accordance with the invention can be cured in a manner custom-ary ~ se by adding a curing agent, for example a primary or secondary polyamine, an anhydride of a polycarboxylic acid or o a catalytically-acting curing agent, such as a tertiary amine, and if appropriate heating the cornposition. The cured products are distinguished especially by a low halogen content.
The invention relates also to a process for the manufacture of cured producLs which com-prises curing the epoxy resins obtainable in accordance with the process of the invention by the addition of a curing agent known ~ se and, if appropriate, heating.
The curable mixtures can, if desired, contain further additives customary ~ se, such as reactive diluents, plasticisers, extenders, fillers and reinforcing agents, for example coaltar, bitumen, textile fibres, glass fibres, carbon fibres, mineral silicates, mica, quartz powder, aluminium oxide hydrate, bentonite, wollastonite, kaolin, silicic acid aerogel or 2~ 97~7 metal powders7 such as aluminium powder or iron powder, and also pigments and dye-stuffs, such as carbon black, oxide dyes and titanium dioxide, and also flame-proofing agents, thixotropic agents, flOw agents (some of which can also be used as mould release agents), such as silicones, waxes and stearates, or adhesion promoters, antioxidants and light stabilisers.
The mixtures of the invention can be used very generally for the manufacture of cured products and can be employed in a formulation adapted to the respective specific field of application, in unfilled or filled state as a component of paint compositions, coating com-positions, lacquers, moulding compositions, dipping resins, whirl sintering powders, in-jection moulding folmulations, tool resins, powder lacquers, casting resins, impregnating resins, laminating resins, adhesives or matrix resins.
The resins obtainable in accordance with the invention are suitable, for example, for use in the fields of surface protection, laminating processes, in construction and especially in electrotechnology and electronics. Compounds with an average of one epoxy group can be used as reactive diluents.
Examples ~: Prepar~tioll of bisph~nol A-di~lycidyl ~ther 50 g (0.08 mol) of solid Oxone(~ are added over a period of three and a half hours at room temperature, with vigorous stirring, to 15.4 g (0.05 mol~ of distilled bisphenol A-diallyl ether (prepared according to DE-A-26 27 045) and 0.66 g of 18-crown-6 in a two-phase system of 50 ml of acetone, 50 ml of dichloromethane and 100 ml of phosphate buffer pH
7.0, the pH being held constant with 15 % NaOH solution. After a further 15 minutes, the phases are separated, 10 ml of acetone, 5 ml of dichloromethane, 100 ml of phosphate.
buffer pH 7.0 and 0.66 g of 1 8-crown-6 are added to the organic phase and, over a period of three and a half hours, a further 50 g (0.08 mol) of solid Oxone(~) is added. After 15 minutes the phases are separated again and the above- described operations are repeated, 30 g (0.05 mol) of Oxone(g) being used. The reaction mixture is then extracted twice with 100 ml of toluene each time, and the combined organic phases are concentrated to 200 ml using a rotary evaporator. The toluene phase is washed three times with 50 ml of lN
NaOH solution each time and five times with 50 ml of water each time, dried overMgSO4, filtered and concentrated by evaporation. 13.6 g (80 %) of a golden yellow liquid having the following properties are obtained:
l~poxy number: 5.11 val/kg (87 %); l125:3730 mPa.s total chlorine content: 425 ppm; hydrolysable chlorine content: 128 ppm.
Example 2: Preparation of bisphenol A-di~yci(lyl ether 87 ml of a 0.1M solution of dimethyldioxirane in acetone [prepared according to W. Adam et al., J. Org. Chem., 52, 2800-3 (1987)] are added at room temperature, under a nitrogen atmosphere, to 0.31 g (1 mmol) of distilled bisphenol A-diallyl ether and stirred for six hours. The solvent and the excess dimethyldioxirane are then distilled off using a rotary evaporator. 0.33 ~ (97 %) of a faintly yellow, clear liquid with an epoxy number of 4.8 val/kg (82 %) is obtained.
Example 3: Preparation of bisphenol A-di-(2,3-epoxybutyl) ether 23 g (0.04 mol) of Oxone(~ dissolved in 100 ml of phosphate buffer pH 7.0 are added dropwise at room temperature, over a period of one and a quarter hours, to 3.36 g (0.01 mol) of distilled bisphenol A-dicrotyl ether (prepared analogously to the diallyl ether according to DE-A-26 27 045) and 0.6 g of 18-crown-6 in a two-phase system of 50 ml of acetone,50 ml of dichloromethane and 50 ml of phosphate buffer pH 7.0, the pH being held constant with 15 % NaOH solution. Subsequently the reaction mixture is stirred for a further one and a half hours and then extracted twice with 100 ml of dichloromethane each time. The combined organic phases are washed t~ice with 50 ml of water eachtime, rendered free of peroxide over sodium sulfite, dried over MgSO4, filtered and con-centrated by evaporation. 3.5 g (95 %) of a clear, light- brown liquid having an epoxy number of 5.05 val/kg (93 %) are obtained.
Example 4: Preparation of bisphenol A~di-(2,3-epoxybutyl) ether 33 ml of a 0.15M solution of dimethyldioxirane in acetone are added at room temperature, under a nitrogen atmosphere, to 0.17 g (0.5 mmol) of distilled bisphenol ~-dicrotyl ether and stirred ~or one and three qu~rter hours. The solvent and the excess dimethyldiox*ane are then distilled off in a rotary evaporator. 0.17 g (92 %) of a faintly yeliow, clear liquid having an epoxy number of 4.9 val/kg (91 %) is obtained.
Example 5: P~epar~tion of poly-4-(2,3-epoxyblltoxy)-styrene a) Preparation of poly-4-(2,3-butenoxy)-styrene.
107.7 g of K2CO3 are added over a period of 10 minutes at room temperature, with stir-ring, to a solution of 60.1 g of Resin(~) M (poly-p-vinylphenol; Maruzen Oil) and 128.3 g of crotyl chloride in 300 ml of l:)MSO and the reaction mixture is then stirred for four and a half hours at 60C. The reaction mixture is then cooled, 300 ml of water are added and extraction is carried out three times with 100 ml of ethyl acetate each time. The combined organic phases are washed three times with 100 ml of water each time, dried overMgSO4, filtered and concentrated by evaporation. 82.8 g (95 %) of a brown resin are ob-tained. l112~ = 1560 mPa.s.
b~ Preparation of poly-4-(2,3-epoxybutoxy)-styrene.
90 g (0.15 mol) of Oxone~ are added over a period of three and a quarter hours at room temperature, with vigorous stirring, to 8.7 g of the polycrotyl ether of Example Sa) and 0.6 g of 18-crown-6 in a two-phase system of 50 ml of acetone, 50 ml of dichloromethane and 10û ml of phosphate buffer pH 7.0, the pH value being held constant with 15 %
NaOH solution. The suspension is then stirred for a further hour and subsequently filtered. The filtrate is extracted three times with 100 ml of methyl ethyl ketone each time, the combined organic phases are washed twice with 100 ml of saturated NaClsolution each time, tested for peroxides with KI-starch paper, dried over MgSO4, filtered and concentrated by evaporation. 9.0 g (95 %) of a brown resin are obtained.
60 = 780 mPa.s; epoxy number = 4.97 val/kg (95 %).
Example 6: Prepar~tion of bisphcnol F-di~lycidyl ether 100.1 g (0.5 mol) of bisphenol F and 133.9 g (1~75 mol) of allyl chloride are introduced into 250 ml of DMSO, and 207.3 g (1.5 mol) of K2CO3 are added in portions over aperiod of one hour. The mixture is then heated to 60C and stirred for four hours at that ~emperature. The reaction mixture is subsequently cooled, poured onto 750 ml of water and ext~acted three times with dichloromelhane. The combined organic phases are washed three times with water, toluene is added and the whole is concen~rated by eva-poration. 132 g of bisphenol F-diallyl ether are obtained in the forrn of a brown liquid. A
portion of this is distilled at 185C/1.3 Pa in a thin-layer evaporator. 14 g (0.05 mol) of the distilled product are dissolved in a two-phase system of 50 ml of acetone,50 ml of di-chloromethane and 100 ml of phosphate buffer pH = 7.0, and 0.66 g (2.5 rnmol) of18-crown-6 are added. Over a period of three and a half hours 60 g (95 mmol) of Oxone~) are then added in portions at room temperature, the pH vallle being held constant with 15 % NaOH. The phases are then separated, 30 ml of acetone, 5 ml of dichloro-methane, 100 ml of phosphate buffer pH value 7.0 and 0.66 g (2.5 mmol) of 18-crown-6 are added to the organic phase, and, over a period of three and a half hours, a further 60 g - lo -(95 mmol) of Oxone(~) is added, with the pH value being held constant. The reaction mix-ture is then diluted with water and extracted three times with dichloromethane. The combined organic phases are washed once with lN NaOH and four times with water, dried over MgSO4, filtered and concentrated by evaporation. 12.6 g of bisphenol F-diglycidyl ether are obtained in the forrn of a clear brown liquid having an epoxy content of 4.42 val/kg (75 %).
Exarnple 7: Preparation of a glycidyl ether of a cresol/formal(lehyde novolak 100 g (û.7 mol) of a cresol/formaldehyde novolak (Mn = 624; Mw = 906) and 11.8 g(0.035 mol) of tetrabutylammonium hydrogen sulfate are dissolved in 160.7 g (2.1 mol) of allyl chloride at 30C, and then 1~0 g (3.5 mol) of NaOH are added in portions over a period of one hour. The mixture is then heated to reflux and stirred for two hours at that temperature. The reaction mixture is cooled, water is added, and extraction is carried out three times with methyl ethyl ketone. The combined organic phases are washed three times with 10 % N~14CI solution and twice with water, dried over MgSO4, filtered and concentrated by evaporation. 126 g of the polyallyl ether of the cresol/formaldehyde novolak are obtained in the forrn of a dark-violet highly viscous resin. 50 g of this crude product are dissolved in as small a quantity as possible of ethyl acetate and filtered with hexane/ethyl acetate = 1:1 through a 20 cm long silica gel column (diameter 10 cm). 45 g of a light-yellow highly viscous resin are obtained. 19.1 g (û.1 mol) of the purifiedpro-duct are dissolved in a two-phase system of 50 ml of acetonc, 50 ml of dichloromethane and 100 ml of phosphate buffer pH = 7.0, and 0.66 g (2.5 mmol) of 18-crown-6 is added.
60 g (95 mmol) of Oxone~ are then added in portions at room temperature over a period of three and a half hours, the pH value being held constant with 15 % NaOH. The phases are then separated, 20 ml of acetone, 10 ml of dichloromethane, 5û ml of phosphate buffer pH value 7.0 and 0.66 g (2.5 mmol) of 18-crown-6 are added to the organic phase, and a ~urther 60 g (95 mmol) of Oxone(~ is added in portions over a period of three and a half hours with the pH value being held constant. The reaction mixture is then diluted with water and extracted three times with ethyl acetate. The combined organic phases are washed once with lN NaOH and three times with water, toluene is added and the whole is concentrated by evaporation. 12 g of the polyglycidyl ether of the cresol/formaldehyde novolak are obtained in the form of a brown solid with an epoxy content of 3.94 val/kg (82 %)
Claims (16)
1. A process for the preparation of epoxy compounds from aromatic allyl ethers having at least one radical of formula II
(II) bonded directly to the aromatic nucleus, in which each of R1, R2 and R3, independently of the others, is hydrogen or Cl-C6alkyl, which comprises epoxidising the starting material, as such or dissolved in an inert solvent, with a dioxirane, approximately from 1 to 20 mols of dioxirane being used per allyl group.
(II) bonded directly to the aromatic nucleus, in which each of R1, R2 and R3, independently of the others, is hydrogen or Cl-C6alkyl, which comprises epoxidising the starting material, as such or dissolved in an inert solvent, with a dioxirane, approximately from 1 to 20 mols of dioxirane being used per allyl group.
2. A process according to claim 1, wherein the aromatic allyl ether is a compound of formula III or a compound that consists essentially of recurring structural units of formula IV or V
(III), (IV), (V), in which m is 1, 2, 3 or 4, n is an integer of from 2 to 12, p is an integer of from 2 to 100, q is 0, 1, 2 or 3, R1, R2 and R3 are as defined in claim 1, R4 is Cl-C6alkyl or halogen, R5 and R6 are each independently hydrogen or Cl-C6alkyl and A is a m-valent aromatic radical of a phenol after removal of the hydroxy groups.
(III), (IV), (V), in which m is 1, 2, 3 or 4, n is an integer of from 2 to 12, p is an integer of from 2 to 100, q is 0, 1, 2 or 3, R1, R2 and R3 are as defined in claim 1, R4 is Cl-C6alkyl or halogen, R5 and R6 are each independently hydrogen or Cl-C6alkyl and A is a m-valent aromatic radical of a phenol after removal of the hydroxy groups.
3. A process according to claim 2, wherein R1 and R2 are hydrogen and R3 is methyl or hydrogen.
4. A process according to claim 2, wherein R1 and R2 and R3 are hydrogen.
5. A process according to claim 2, wherein the aromatic allyl ether is a compound of formula III, IV or V in which m is 2, n is from 3 to 6, p is from 5 to 40, q is O, A is a di-nuclear radical of a bisphenol and R1, R2 and R3 are hydrogen.
6. A process according to claim 1, wherein the aromatic allyl ether is introduced into a vessel as such or dissolved in a solvent that is inert under the reaction conditions, and a dioxirane solution in a ketone is added, approximately from one to twenty mols of di-oxirane being used per mol of double bond to be epoxidised.
7. A process according to claim 1, wherein the aromatic allyl ether is introduced as such, or dissolved in a solvent that is inert under the reaction conditions, in a vessel together with a phase transfer catalyst and in conjunction with a ketone and water, so that a two-phase system results, the aqueous phase containing a buffer for establishing a pH value in the range of approximately from 6 to 10, and subsequently a peroxomonosulfate is added, the amount of peroxomonosulfate being approximately from one to ten mols per mol of double bond to be epoxidised.
8. A process according to claim 7, wherein the phase transfer catalyst used is a crown ether or a quaternary ammonium or phosphonium salt, and the buffer used is a phosphate buffer with which a pH value of approximately 7 is established.
9. A process according to claim 7, wherein the aromatic allyl ether dissolved in an inert solvent is introduced into a vessel together with a crown ether or a quaternary ammonium salt as phase transfer catalyst, and an aqueous acetone phase adjusted to a pH value of from 6.5 to 7.5 is used, the peroxomonosulfate being added in solid form and the pH
value being held constant by the addition of an aqueous solution of a base.
value being held constant by the addition of an aqueous solution of a base.
10. A process according to claim 9, wherein the aqueous solution of a base is sodium hydroxide solution.
11. A process according to claim 1, wherein the reaction temperatures are from 0 to 30°C.
12. A process according to claim 1, wherein the epoxidation reagent used is bis-trifluoromethyldioxirane.
13. A process according to claim 1, wherein the epoxidation reagent used is dimethyl-dioxirane.
14. A process according to claim 1, wherein the aromatic allyl ether is purified by chromatography or by distillation before the epoxidation step.
15. A method of manufacturing cured products, which comprises curing the epoxy resins obtainable in accordance with the process of claim 1 by the addition of a curing agent known per se.
16. A method according to claim 15, wherein the curing is performed by heating.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CH426088 | 1988-11-17 | ||
| CH4260/88-8 | 1988-11-17 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2002977A1 true CA2002977A1 (en) | 1990-05-17 |
Family
ID=4272814
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002002977A Abandoned CA2002977A1 (en) | 1988-11-17 | 1989-11-15 | Process for the preparation of epoxy compounds |
Country Status (5)
| Country | Link |
|---|---|
| EP (1) | EP0370946A3 (en) |
| JP (1) | JPH02180877A (en) |
| KR (1) | KR900007898A (en) |
| BR (1) | BR8905816A (en) |
| CA (1) | CA2002977A1 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5578740A (en) * | 1994-12-23 | 1996-11-26 | The Dow Chemical Company | Process for preparation of epoxy compounds essentially free of organic halides |
| US7671114B2 (en) | 2004-01-26 | 2010-03-02 | Henkel Corporation | Adhesive of substituted oxirane or oxetane compound with silver-based, lead-free solder |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TW201200504A (en) * | 2010-03-18 | 2012-01-01 | Dow Global Technologies Llc | Process for preparing divinylarene dioxides |
| JP6524872B2 (en) * | 2015-09-17 | 2019-07-03 | 東洋インキＳｃホールディングス株式会社 | Internal epoxy compound having benzene ring and thermosetting composition |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS59227872A (en) * | 1983-06-08 | 1984-12-21 | Sumitomo Chem Co Ltd | Preparation of epoxy compound |
-
1989
- 1989-11-08 EP EP89810847A patent/EP0370946A3/en not_active Withdrawn
- 1989-11-09 KR KR1019890016200A patent/KR900007898A/en not_active Application Discontinuation
- 1989-11-15 CA CA002002977A patent/CA2002977A1/en not_active Abandoned
- 1989-11-16 JP JP1298743A patent/JPH02180877A/en active Pending
- 1989-11-17 BR BR898905816A patent/BR8905816A/en unknown
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5578740A (en) * | 1994-12-23 | 1996-11-26 | The Dow Chemical Company | Process for preparation of epoxy compounds essentially free of organic halides |
| US7671114B2 (en) | 2004-01-26 | 2010-03-02 | Henkel Corporation | Adhesive of substituted oxirane or oxetane compound with silver-based, lead-free solder |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH02180877A (en) | 1990-07-13 |
| BR8905816A (en) | 1990-06-12 |
| EP0370946A2 (en) | 1990-05-30 |
| KR900007898A (en) | 1990-06-02 |
| EP0370946A3 (en) | 1990-08-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4789711A (en) | Multifunctional epoxide resins | |
| US4284574A (en) | Diglycidyl ethers of di-secondary alcohols, their preparation, and curable compositions containing them | |
| CA1213610A (en) | Process for the preparation of n-substituted n- cyancarboxylic acid amides and their use in curable epoxide resin mixtures | |
| US3787451A (en) | Epoxides of alkoxy-substituted tri(hydroxyphenyl)alkanes | |
| US4677170A (en) | Polyepoxides and the use thereof | |
| KR101616898B1 (en) | Epoxy resin composition | |
| US4474929A (en) | Polyglycidyl ethers of branched novolacs | |
| EP0526401B1 (en) | Process for the preparation of glycidyl ethers of di-secondary alcohols with high monomer content | |
| CA2002977A1 (en) | Process for the preparation of epoxy compounds | |
| KR910004902B1 (en) | Phenol ethers containing epoxide groups | |
| US4661644A (en) | Brominated epoxyaromatic compounds | |
| JPH0832696B2 (en) | 2,6-Disubstituted 4-epoxypropylphenylglycidyl ether and method for producing the same | |
| EP0453275A1 (en) | Process for producing epoxy compound | |
| KR960007027B1 (en) | Pneumatic tire | |
| EP0379940B1 (en) | Glycidyl derivatives of 2,6-dibromo-3,5-dialkyl-4-hydroxybenzyl ethers | |
| US3455949A (en) | Hexahydrophthalimide polyepoxide compounds | |
| JPS59231078A (en) | Cyclic fatty diglycidyl ether, manufacture and curable mixture containing same | |
| KR100305217B1 (en) | Sulfonylaminimide and cationic polymerization composit containing them | |
| JP2003286276A (en) | New alicyclic epoxy compound | |
| KR20000029811A (en) | Polyglycidyl ethers of secondary alcohols | |
| JPS6372721A (en) | Epoxy resin composition | |
| JPS6263537A (en) | Brominated hydroxy aromatic compound | |
| JPH01207318A (en) | Novel epoxy resin and production thereof | |
| NZ229571A (en) | Epoxy terminated ring-brominated diaryl alkane derivatives useful as precursors for epoxy resins |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Dead |