DD219779A1 - METHOD FOR THE EPOXIDATION OF CYCLOPENTADIENHOLDING MIXED POLYMERISES - Google Patents

Abstract

The production of an epoxide-functionalized reactive polymer succeeded by reaction of an oxidation-stable cyclopentadiene-containing copolymer "in situ" with a mixture of an organic carboxylic acid and H2O2 in the presence of a solvent or solvent mixture. The resulting products can be used in the known typical applications (adhesive and coating sector, resin synthesis, etc.).

Description

Title of the invention,

Process for the epoxidation of cyclopentadiene-containing copolymers. ·

Field of application of the invention

The invention relates to an economical and rational process for the epoxidation of cyclopentadiene-containing mixed polymers. The epoxidized hydrocarbon resin is further modifiable and can be used in modified or unmodified form in the known typical applications such as in the adhesive or coating sector and for resin synthesis »

3 * 8

Characteristic of the known technical solutions

Methods for the epoxidation of unsaturated polymers according to the "in situ" peracid method are already known. Thus, polybutadiene, polyisoprene and copolymers of butadiene with styrene or acrylonitrile by means of mixtures of acetic acid and hydrogen peroxide [CE. WHEELOCK. : Ind. Engn. Chem. 5CJ ₁ 299 (1958)] are converted into the corresponding epoxides, if at the same time strong acids such as HgSO ₄₁ ^H 3PC> 4 or the insoluble sulfonated copolymers of styrene with little divinylbenzene (US Patent 2,946,756, US Patent 2,959. 531) are present.

The products are mainly suitable for protective coatings (US-PS 2,893,885) or are used as a lubricant additive (DE-OS 2,554,093).

A disadvantage of these methods is that with polybutadiene and polyisoprene starting materials are used, which could also be processed into valuable rubber products (DE-OS 3,006,001).

Also known are processes for the epoxidation of polymethylcyclopentadiene or of polycyclopentadiene (British Pat. No. 787,293, US Pat. No. 3,130,207). The products have the disadvantage that incomplete saturation of the double bonds in the polymer crosslinks and discoloration occur. In DD-WP 248.516), an oxidation-stable cyclopentadiene-containing copolymer according to DD-WP 240.762 is used for the first time, wherein it is found that an optimal oxirane oxygen content can be achieved with further improved storage stability of the resins.

Disadvantages of the method are in the field of costs and in the field of safety requirements for the use of peracetic acid.

Object of the invention

The aim of the invention is the development of an economical and rational process for the epoxidation of an oxidation-stable cyclopentadiene-containing copolymer based on indigenous raw materials.

Presentation of the essence of the invention

The invention has for its object to develop a process for the preparation of an epoxidfunktionalisierteh, oxidation stable cyclopentadiene-containing copolymer, which is to lay on a low-cost variant with low safety outlay value. The object is achieved according to the invention by converting an oxidation-stable 6 cyclopentadiene-containing copolymer "in situ" with a mixture of an organic carboxylic acid and hydrogen peroxide in the presence of a solvent or solvent mixture into an epoxide-functionalized reactive copolymer. For the epoxidation, oxidation-stable unsaturated copolymers are used Cyclopentadiene, preferably from 10 to 65 mol%, and composed of eC-methylstyrenes According to the invention, the copolymers used in addition to cyclopentadiene and oC-methylstyrene also other cationically polymerizable monomers such as styrene, Vinyltoluen, Inderi, isobutene or mixtures thereof and molecular weight regulators such as isobutene oligomers containing preferably 8 to 16 carbon atoms, The copolymers can be epoxidized depending on the procedure with or without prior isolation from the polymerization n.

As the oxidizing agent mixture, an organic carboxylic acid and aqueous hydrogen peroxide is used, optionally in the presence of an acidic catalyst is used »

For the epoxidation 0.10 to 2.50 moles, but preferably 0.75 to 1.50 moles of H ₂ O _{2 are used} per cyclopentadiene double bond. The concentration of the oxidizing agent is preferably between 30 and 40% by mass.

, , , · ^ Are aliphatic carboxylic acids, preferably acetic acid and .Ameisensäure used, preferably a carboxylic acid amount of 0.5 to ₁ I O mole per Cyclopentadiendoppelbindurg is selected. In particular, when using longer-chain less acidic carboxylic acids for epoxidation, the use of an acidic catalyst is necessary. Owing to their easy separability and selectivity with respect to peracid formation, acidic ion exchangers, in particular polystyrene sulfonic acids cross-linked with 4 or 8% divinylbenzene (WOFATIT FK 4 and FK 8), are used for this purpose.

The mass ratio between the ion exchange resin and the copolymer used is between 0.25 and 3.0, but preferably between 0.5 and 1.0. The epoxidation is carried out in a solvent. Suitable are aromatic and cycloaliphatic solvents, but also chlorinated hydrocarbons having 1 to 2 carbon atoms such as chloroform, It can also be used solvent mixtures.

Depending on the solubility, the concentration of the solution of the copolymer to be epoxidized can be between 60 and 60

1

600 g * l and is preferably from 100 to 150 g · 1 The epoxidation temperatures are according to the invention between 290 K and 340 K, but preferably in the range of 300 K to 320 K.

The procedure according to the invention is to dissolve the cyclopentadiene-containing copolymer in a solvent or mixture and to introduce it together with the respective carboxylic acid and optionally with the appropriate amount of an acidic ion exchange resin.

For this purpose, an aqueous hydrogen peroxide solution is added so that the reaction temperature does not increase by more than 5 K. After complete addition, the reaction mixture is ^r

· ..-. ^ν . , '- 5 -. ; , ''. , ''. ''';

stirred intensively for 1 to 8 h.

It can also be 39 that the copolymer to be epoxide-terminated is used without prior isolation from the polymerization mixture after complete removal of the initiator residues directly in solution for the reaction described.

In the presence of an acidic ion exchange resin, this is separated by filtration after completion of the reaction and washed with the organic solvent used in each case 0 '.

The organic phase of the reaction mixture is separated, successively with saturated aqueous NaCl solution, saturated aqueous NaCl solution containing KOH and washed neutral with water, dried and concentrated to remove the solvent in vacuo, '' The isolation of the epoxidized cyclopentadienhaltigen Copolymers can also be obtained by precipitating the organic phase of the reaction mixture in a non-solvent such as methanol. The copolymers obtained in this way contain, depending on the epoxidation conditions, 0.1 to 3.5% by mass of oxirane oxygen at double bond conversions of 10 to 85 % "There are in all cases obtain white reaction products that contractually with other hydrocarbon resins borrowed are and are extremely resistant to oxidation to air and pure oxygen, due to the reactive nature of the oxirane ring, it is possible that Polydienepoxide in many ways unforgiving lent · next to modify what they can be opened to a wide range of applications.

The examples given are intended to illustrate the process according to the invention;

Exemplary embodiments:

Example 1 to 8:

In a temperature-controlled 100 ml glass flask with stirrer, dropping funnel, internal thermometer and shielding gas connection

4.00 g of a synthesized by cationic polymerization cyclopentadiene cG-methylstyrene copolymers dissolved in 40ml benzene and presented together with 1.02g of a commercial 36% formic acid.

The copolymer had the following characteristic data: cyclopentadiene content: 45 mol%

average molecular weight: 3000 g »mol

Isomerization degree of cyclopentadiene units: 23 %

Elemental Composition: 89.76 M% C

9.59 % by mass H

¹ 0.65% by mass Cl

By means of dropping funnel, the respective amount of 32.4% strength aqueous hydrogen peroxide solution is slowly added, so that the temperature does not rise by more than 5 K. After completion of the addition of the contents of the flask is brought to the required temperature of 323 K and stirred vigorously at this temperature for 2 h. Thereafter, distilled water is added in the same volume, the benzene phase separated and washed successively with saturated aqueous NaCl solution, saturated aqueous NaCl solution with 5 M% KOH and several times with distilled water until the aqueous phase is neutral. The organic phase is treated with Na ₂ SO. dried, filtered and concentrated at 303 K in a water-jet vacuum.

Oie amounts of HpOp solution and the characteristics of the epoxidized in these examples copolymers are summarized in Table 1.

Example 9 and 10;

The epoxidation is carried out as described in Examples 1 to 8, but different amounts of 86% formic acid are used. The results obtained are shown in Table 2.

Example 11 and 12: '

The epoxidation is carried out as described in Examples 1 to 8,. Only the solvent is not benzene, but

- 7 - '' ·

Chloroform or xylene used. The epoxidized products have the characteristic data compiled in Table 3.

Example 13 to 27:

The epoxidation is carried out as described in Examples 1 to 8, but the temperature or the reaction time is varied. The results obtained are shown in the

belle 4 shown. - /

'' (- ' ^: ·.,

Example 25 to 27:

The reaction is carried out as described in Examples 1 to 8, except that instead of formic acid acetic acid is used and used as a solvent in addition to benzene, chloroform and xylene. The following oxirane oxygen values are obtained for these solvents:

Benzene: 0.41% by mass of chloroform: 0.52% by mass of xylene,: 0.40% by mass

Example 28 to 30:

For epoxidation of a cyclopentadiene oi / methylstyrene copolymers (cf. · Examples 1 to 8) were dissolved in benzene and _t l together with 15 g of conc 4.00 g. Acetic acid and the respective amount of a sulfonated ion exchange resin (VVOFATIT FK 4 or FK 8) submitted. To this, 2.00 g of a 32.4% solution of aqueous HgOg solution are slowly added while stirring. After the reaction temperature of 323 K has been set, the mixture is stirred vigorously for 2 h. The ion exchanger is recovered by filtration and washed twice with benzene. The organic phase of the reaction mixture is separated off and combined with the washing solutions. The further work-up is carried out as described in Examples 1 to 8. The epoxidation results are summarized in Table 5 for various ion exchanger types and amounts . provides. - - .. ··

Table 1: Amounts of HpOg and characteristics of the epoxidized in Examples 1 to 8 polymers

example H ₂ O ₂ Cg] Dodzahl double bond Oxirane oxygen Sales [% 3 substance [Ma-% 3 1 0.40 126 7 '15 0.20 2 0.80 77 48 0.91 3 1.20 74 50 1.66. 4 1.50 55 63 2.22 5 2.00 44 70 2.34 6 3.00 40 73 2.77 7 4.00 38 74 2.86 8th 5.00 35 78 3.13

Table 2: Use rates of formic acid and characteristic values of the polymers epoxidized in Examples 9 and 10

Example ants-ood number double-bond qxirane-acidic acid sales

Cg] ΐ% 3 [Ma-% 3

9 10

2.04 4.08

43 45

1.91 1.80

Table 3: Solvent Variation in the Epoxidation of a Cyclopentadiene-Ot-Metyl Styrene Copolymer

Example solvent 3-iodo double bond »

number of sales C% 3

Oxirane oxygen CMa%]

11 chloroform 28

12 xylene 66

81

54

3.02 2.05

Table Ax Results of the temperature and reaction time variation in the epoxidation of cyclopentadiene-methylstyrene copolymers ^a '

example tempera Time 3od- double bond Oxirän-sour tur CK] ChG number sales [%] substance [Ma-% 3 13 295, '. 0.5 127 14 0.40 14 295 1.0 107 28 0.55 15 295 2.0 93 37 0.93 16 295 3.0 71 52 1.21 17 295 4.0 59 60 1.75 18 295 5.0 52 66 2.29 19 295 6.0 45 70 2.96 20 295 , 7.0 38 74 3.26 21 323 1.0 44 70 2.31 22 323 2.0 26 82 2.90 23 323 3.0 18 88 2.91 24 323 4.0 17 89 2.82

a) H ₂ O ₂ amount: 4.00g

Table 5: Types and amounts of acidic ion exchanger (WOFATIT) in the epoxidation with HgOVEssigsäure

example ion exchanger amount Oxirane oxygen CMa-% 3 ' 28 FK 4 0 0.41 29 FK 4 1.0 1.90 30 FK 4 2.0 2.50 31 FK 8 2.0 2.65 32 FK 8 4.0 2.60 33 FK 4 8.0 2.42

Claims (5)

- 10 claim for invention: 1. A process for the epoxidation of oxidation-stable cyclopentadiene-containing copolymers characterized in that the copolymers "in situ * with a mixture of an organic carboxylic acid and HaO ₂ / in the presence of a solvent or» mixture are converted into an epoxy-functionalized reactive copolymer · 2. The method according to item 1, characterized in that are used as organic carboxylic acids, preferably formic acid and acetic acid. 3. The method according to item 1, characterized in that formic acid in an amount of preferably 0.50 to 1.0, MoI per double bond and a concentration of preferably more than 85 Ma ~% is used. 4. The method according to item 1, characterized in that are used for the epoxidation with acetic acid / hydrogen peroxide acidic ion exchangers as catalysts. 5. The method according to item 1, characterized in that the hydrogen peroxide in an amount of 0.10 to 2.50 mol, preferably 0.75 to 1.50 mol per cyclopentadiene double bond and a concentration of preferably 30 to 40% by mass is used. '