DD256709A1 - METHOD FOR PRODUCING EPOXY-FUNCTIONALIZED POLYDIENES - Google Patents

Abstract

The invention relates to a process for the preparation of epoxide-functionalized polydienes. For the preparation of epoxide-functionalized polydienes, diene-containing copolymers were converted into reactive epoxide-functionalized hydrocarbon resins by reaction with organic peracids produced in situ from H2O2 and aliphatic carboxylic anhydrides in the presence of a solvent or mixture. The epoxidized products can be used in the known typical applications (adhesive and coating sector, resin synthesis, etc.).

Description

Field of application of the invention

The invention relates to a process for the preparation of epoxide-functionalized polydienes.

The resins according to the invention can be used in the adhesive and coating sector, for the production of hard resins, etc.

be used.

Characteristic of the known technical solutions

It is known to convert ethylenically unsaturated compounds by reaction with percarboxylic acids into the corresponding epoxides. As peracids were originally perbenzoic acid, monoperphthalic acid, peracetic acid and the like. used, with which simple olefins but also unsaturated polymers were epoxidized (DE-AS 1038283, DE-AS 1040794, E-PS 888133, DE-AS 1111399, DE-OS 2542709, US-PS 3130207).

Disadvantages of the methods are in the area of costs and in the field of safety requirements when dealing with organic peracids.

The synthesis of the percarboxylic acid to be carried out beforehand and thus the direct handling of it is omitted if it is generated "in situ" in the H ₂ O ₂ reaction mixture and a carboxylic acid in the presence of acidic catalysts (eg, sulfonated ion exchange resins) 1,3-butadiene and 1,3-isoprene, but also butadiene / styrene and butadiene / acrylonitrile copolymers are converted into the corresponding epoxide-functionalized products (CEWheelock: Ind. Engn. Chem. 50, 299 [1958], US-PS 2,946,756; The functionalized hydrocarbon resins are mainly used for protective coatings or as lubricant additives (US-PS 2893885, DE-OS 2554093).

A disadvantage of the use of butadiene and isoprene polymers is that the monomers could also be used for the production of valuable rubber products.

Polydienes containing cyclopentadiene have also been converted into epoxide-functionalized products using preformed but also "in situ" peracid generated from H ₂ O ₂ / carboxylic acids (DD-WP 206155).

The disadvantage here is that the diene used for the synthesis of the polymers must be obtained only in an energy-consuming upstream process step from dicyclopentadiene.

A process for the epoxidation of polymers containing dicyclopentadiene is also described. However, only with preformed organic peracids high Epoxidierungsgräde be achieved, while with "in situ" produced from H ₂ O ₂ and carboxylic acids peracids only small double bond conversions Oxiransauerstoffanteilen in polymers can be achieved below 1.0%.

Object of the invention

The aim of the invention is the development of an economical and rational process for the epoxidation of dienhaltigen ~ copolymers on the basis of low-priced partly not optimally used raw materials.

Explanation of the essence of the invention

The invention has for its object to develop a process for the preparation of epoxide-functional dienhaltigen copolymers, which should be placed on a low-cost variant with low safety outlay value.

The object is achieved in that diene-containing copolymers containing dicyclopentadiene as preferred diene and other cationically polymerizable monomers, by reaction with "in situ" from H2O2 and aliphatic carboxylic anhydrides produced organic peracids in the presence of a solvent or mixture in reactive epoxide-functional hydrocarbon resins be transferred.

For the epoxidation, unsaturated copolymers are used which preferably contain dicyclopentadiene but also cyclopentadiene as the diene component. Dicyclopentadiene is used in both coal and petroleum processing and is still not optimally utilized. It can be used after the separation from technical concentrates, as well as the available in a thermal monomerization process cyclopentadiene, for the synthesis of unsaturated copolymers. Since cyclopentadiene only has to be obtained from dicyclopentadiene in an energy-consuming additional process step to be carried out, the use of dicyclopentadiene-containing interpolymers for epoxidation is preferred, especially since thermal fractions can be used without prior separation and purification of the diene for their synthesis.

According to the invention, in particular those copolymers are used for epoxidation, in addition to the diene styrene, a-methylstyrene, vinyltoluene, indene, isobutene, diisobutene and other cationically polymerizable monomers or mixtures thereof.

Depending on the process procedure, the copolymers can be epoxidized with or without prior isolation from the polymerization mixture.

The "in situ" epoxidation of cyclopentadiene-containing copolymers with H ₂ O ₂ and carboxylic acid, in particular formic acid, leads to products having a relatively high oxirane oxygen content, while the results obtained in the epoxidation of dicyclopentadiene-containing polymers by this procedure are unsatisfactory.

The process according to the invention is therefore such that an aliphatic carboxylic acid anhydride is used instead of the carboxylic acid for the epoxidation. This reacts selectively with H ₂ O ₂ (but not H ₂ O) "in situ" to the corresponding percarboxylic acid, wherein the active oxygen of H ₂ O ₂ can be used completely.

According to the invention, H ₂ O _{2 is used} in an amount of 0.50 to 2.50 mol, but preferably 1.00 to 1.50 mol, per polydiene double bond and in a concentration of preferably 30 to 40%.

As the aliphatic carboxylic acid anhydride, acetic anhydride is preferably used in an amount of preferably 1.00 moles per mole of H ₂ O ₂ .

According to the invention, a buffer is added to the epoxidation mixture, in particular CH ₃ COONa.3H ₂ O being used in an amount of 10%, based on the amount of H ₂ O ₂ solution.

The epoxidation is carried out in a solvent. Particularly suitable are chlorinated hydrocarbons having 1 to 2 carbon atoms such as CHCl ₃ , but also aromatic and cycloaliphatic solvents in which the mixed polymers dissolve. It is also possible to use solvent mixtures. The concentration of the solution is between 60 and 600 g · Γ ¹ , but preferably at 100-150 g · Γ ¹ .

The procedure according to the invention is to dissolve the polydiene in a solvent or mixture and to introduce the solution together with the aliphatic carboxylic acid anhydride. At a preferred temperature of 40 to 50 ° C, aqueous H ₂ O ₂ is added to this mixture with vigorous stirring, together with the buffer dissolved therein.

After completion of the addition is stirred for 3 to 4 hours and added in the same volume of water. The organic phase is separated, washed successively with saturated aqueous NaCl solution, saturated aqueous NaCl solution with 5% KOH and with H ₂ O neutral, dried with Na ₂ SO ₄ and concentrated at 40 ⁰ C in vacuo. The isolation of the reaction product can also be done by precipitation in a non-solvent such as CH ₃ OH.

The obtained white epoxy-functionalized copolymers are compatible with other hydrocarbon resins and are characterized by a high reactivity and at the same time good storage stability. They can be subsequently modified in the known manner and can be used in a variety of applications.

The following examples are intended to explain the process of the invention in more detail.

example 1

At a temperature of 40 ° C., 40.0 g of a dicyclopentadiene / styrene copolymer containing 50 mol% of diene are dissolved in 400 ml of CHCl ₃ in a temperature-controllable stirred flask with stirrer, dropping funnel and internal thermometer and charged together with 26.0 g of acetic anhydride. 3.0 g of CH ₃ COONa 3 H ₂ O dissolved in 30.5 g of 30% strength H ₂ O ₂ (1.50 mol per double bond) are metered into the mixture with stirring. After completion of the addition is stirred for 3 h at 4O ⁰ C and 400 ml of water added. The organic phase is separated off, washed successively with saturated aqueous NaCl solution, saturated aqueous NaCl solution with 5% KOH and with H ₂ O until neutral and dried with Na ₂ SO ₄ . After separation of the drying agent, the solvent is removed on a rotary evaporator at 40 ° C in vacuo. The drying of the residue takes place in an oil pump vacuum at the same temperature. The epoxidized product contains 2.25% oxirane oxygen at a double bond conversion of 43.1%.

Example 2

The epoxidation is carried out as described in Example 1, except that a Dicyclopentadien / styrene copolymer with 80Mol .-% dicyclopentadiene is used and as Epoxidierungsgemisch 62.0 g of acetic anhydride, 68.4 g of 30% H ₂ O ₂ and 6.8 g CH ₃ COONa · 3H ₂ O can be used. The double bond conversion is 52.4%, the oxirane content 3.74%.

Examples 3 to 6

The epoxidation is carried out as described in Example 1 with a 1 ii-dicyclopentadiene / styrene copolymer, except that the amount of the oxidizing agent mixture used is varied. Table 1 shows the results obtained.

Table 1: "in situ" -Epoxidierung of Polyfdicyclopentadien-co-styrene) with different amounts of H2O2, acetic anhydride and CH ₃ COONa 3H ₂ O;.

example acetan H ₂ O ₂ H ₂ O ₂ CH ₃ COONa -3H ₂ O double oxirane hydride (G) (Moles per (G) bind.- angry- (?) .. Ooppelbind.) sales material 3 8.7 10.2 · 0.50 1.0 12.0 0.69 4 17.3 20.3 1.00 2.0 36.3 1.47 5 34.6 40.6 2.00 4.1 54.7 2.05 6 43.3 50.8 2.50 5.1 56.3 2.39

Examples 7 to 10

The epoxidation is carried out as described in Example 1, except that the solvents used are benzene, toluene, xylene and 1,2-dichloroethane. The results are summarized in Table 2.

Table 2: Solvent variation in the epoxidation of 1: 1 dicyclopentadiene / styrene copolymers with H2O2 / acetic anhydride

example solvent double bond oxirane sales (%) oxygen(%) 7 benzene 36.3 1.95 8th toluene 34.0 1.88 9 xylene 34.2 1.77 10 1,2-dichloroethane 49.6 1.97

Examples 11 to 19

For epoxidation 40.0 g of a 1: 1 copolymers are used, which consists of cyclopentadiene and α-methylstyrene. The double bond conversions and oxirane shares are influenced by the solvent as well as by the amount of epoxidizing agent used. Table 3 shows the results obtained.

Table 3: "in situ" epoxidation of poly (cyclopentadiene-co-a-methylstyrene) with H ₂ O ₂ / acetic anhydride under various reaction conditions

example solvent acetan H ₂ O ₂ H ₂ O ₂ CH ₃ COONa • 3 H ₂ O double bond Oxiransauer- hydride (G) (Moles per (G) sales (%) material(%) (G) Doppelbind.) 11 benzene 33.0 36.6 1.50 3.7 80.3 4.12 12 toluene 33.0 36.6 1.50 3.7 74.9 3.85 13 xylene 33.0 36.6 1.50 3.7 71.7 3.33 14 1,2-dichloroethane 33.0 36.6 1.50 3.7 82.0 2.78 15 chloroform 33.0 36.6 1.50 3.7 84.1 3.55 16 chloroform 11.0 12.2 0.50 1.2 47.8 2.10 17 chloroform 22.0 24.2 1.00 2.4 79.3 3.15 18 chloroform 44.0 48.4 2.00 4.8 87.7 3.86 19 chloroform 55.0 60.6 2.50 6.1 93.0 3.50

Claims (5)

1. A process for the preparation of epoxy-functionalized polydienes, characterized in that diene-containing copolymers containing as diene component preferably dicyclopentadiene and other cationically polymerizable monomers, by reaction with "in situ" from H ₂ O ₂ and aliphatic carboxylic anhydrides produced organic peracids in the presence of a Solvent or mixtures are converted into reactive epoxy-functionalized hydrocarbon resins. 2. The method according to item 1, characterized in that as the aliphatic carboxylic anhydride preferably acetic anhydride in an amount of preferably 1.00 moles per mole of H ₂ O ₂ is used. 3. The method according to item 1, characterized in that H ₂ O ₂ in an amount of 0.50 to 2.50 mol, but preferably 1.00 to 1.50 mol per double bond and in a concentration of preferably 30 to 40% is used. 4. The method according to item!, Characterized in that the copolymers are epoxidized with or without prior isolation from the polymerization mixture after separation of the Coinitiatorreste. 5. The method according to item 1, characterized in that are used as solvent chlorinated hydrocarbons having 1 to 2 carbon atoms, but also aromatic and cycloaliphatic solvents or mixtures thereof.