DE1260793B - Process for the polymerization of olefinic unsaturated organic compounds - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

DESIGN SCREEN

Int. CL:

C08f

German class: 39 c-25/01

Number: 1260793

File number: W 38990IV d / 39 c

Filing date: April 15, 1965

Open date: February 8, 1968

It is known that olefinically unsaturated compounds with the help of various catalysts or initiators can be polymerized. As such, z. B. aromatic and aliphatic Diacyl peroxides, various peresters of aliphatic and aromatic carboxylic acids, alkyl and aralkyl hydroperoxides, Dialkyl and diaralkyl peroxides, ketone peroxides and some azo compounds have been used for a long time. From the group of diacyl peroxides are for example benzoyl peroxide, acetyl, propionyl, decanoyl and lauroyl peroxide manufactured and used on an industrial scale. However, these diacyl peroxides have several disadvantages on; For safety reasons, the benzoyl peroxide must only contain 25% water or 50% plasticizer be put on the market in paste form. Apart from the fact that in many cases with the Catalyst interfering amounts of plasticizer can get into the final polymer, means the precise dosing and homogeneous mixing of solid or pasty peroxide catalysts often great difficulties in the compounds to be polymerized. The use of benzoyl peroxide the curing of unsaturated polyester resin compositions also leads to products that show a tendency to yellow in daylight. Acetyl and propionyl peroxide can because of them Hazardous can only be used and offer in highly diluted form for technical purposes in most 3c cases no advantages over benzoyl peroxide. Decanoyl and lauroyl peroxide are relatively harmless connections, but they are fixed and in certain, with some technical polymerization processes used solvents sparingly soluble.

Also p-monomethoxybenzoyl peroxide known from US Pat. No. 2,858,326 as a polymerization catalyst is highly sensitive to shock and heat and, for safety reasons, can only be used in phlegmatized form are used, so that its technical use has essentially the same disadvantages adhere like benzoyl peroxide.

The inventive method for the polymerization of olefinically unsaturated organic compounds by means of a polymerization catalyst consisting of a diacyl peroxide is thereby characterized in that the diacyl peroxide is a compound of the general formula

// ° Ί

AO- (CH ₂ ) "- C (

M) -L-

Process for the polymerization of olefinic
unsaturated organic compounds

Applicant:

Wallace & Tiernan G. m. B. H., 8871 Wasserburg

Named as inventor:

Dr. Elemer Faltusz, 8883 Gundelfingen

where A is an alkyl radical or an alkoxyalkyl or phenoxyalkyl radical with preferably 3 to 10 carbon atoms or a phenyl radical, which in turn can be substituted by an alkyl or alkoxy group, and η = 2 or 3, optionally in combination with an accelerator and the polymerization is carried out at temperatures of from about 25 to about 15O ⁰ C. The representatives of this new group of diacyl peroxides have several advantages over the known diacyl peroxides listed above. Regardless of whether the alkyl radical A has a normal, branched or cyclic structure, these dialkoxyalkyl peroxides are liquid under normal conditions and with up to 10 carbon atoms, which ensures good metering and homogeneous distribution in the compounds to be polymerized. In contrast to benzoyl peroxide, these new diacyl peroxides do not cause yellowing if they are used to cure polyester resin compounds. Another advantage over the known diacyl peroxides, which are only sparingly soluble in certain solvents, is the excellent solubility of the diacyl peroxides used for the process according to the invention. In addition, they are generally completely insensitive to impact, which makes the use of phlegmatizers unnecessary. The substituent A in the general formula given above can consist of any primary or secondary alkyl, alkoxyalkyl, phenyl, phenoxyalkyl or alkoxyphenyl radical with preferably 3 to 10 carbon atoms. Suitable substituents are therefore, for example, n-propyl, η-butyl, n-pentyl, isoamyl, n-hexyl, n-octyl, 2-ethylhexyl, 3,5,5-trimethylhexyl, n-decyl -, isodecyl and n-butoxyethyl, phenyl, methoxyphenyl, phenoxyethyl radicals.

For the production of those to be used according to the invention Diacyl peroxides can be used in virtually any

809 507 / 6S2

the known diacyl peroxides commonly used method can be applied. It is expedient to use an undiluted acyl halide of the formula _n i or an acyl halide of the formula n i dissolved in a suitable solvent

AO- (CH ₂ ) ,, -C ^

where A and η have the abovementioned meaning and X, for example chlorine or bromine, a halogen atom, with an inorganic peroxide, for example, an alkali or Erdalkaliperoxyd, in aqueous solution, with stirring, at temperatures of about -15 to +25 ⁰ C in order. Suitable solvents for the above acyl halides, which are obtained from the corresponding easily accessible carboxylic acids with the usual chlorinating agents, such as. B. PCI3 or SOCI2, are, inter alia, aliphatic, cycloaliphatic or aromatic hydrocarbons, diethyl ether or various phthalic acid esters, such as dimethyl or dibutyl phthalate. After the usual cleaning washes, the reaction product is dried and, if desired, the solvent is distilled off under reduced pressure. The drying and the removal of the solvent can also be carried out in one step if the solvent used forms an azeotropic mixture with water. The yields are about 60 to about 90% of theory, depending on the experimental conditions chosen and the type of diacyl peroxide produced.

The half-life of peroxides is often used as a measure of the catalyst effectiveness, where this is defined as the time required at the given temperature, so that half of the originally present peroxide decomposes. It is well known that most of them show organic peroxides in dilute solution in inert solvents a monomolecular decomposition reaction, the half-life being constant and essentially only dependent on the temperature is. There is a known method for determining the half-life of organic peroxides in that a 0.2 molar benzene solution of the peroxide in question at constant temperature warmed up. -

Table 1 shows the half-lives of some of the diacyl peroxides which can be used according to the invention listed in comparison to known diacyl peroxides.

Table 1

Diacyl peroxide Half-life
at 70 C
in hours Decomposition
constant
Hour- ¹ Di-3-decyloxypropionyl-
peroxide
Di-4-phenoxybutyryl
peroxide 6.66
3.65 0.1041
0.190

Half-life Decomposition Diacyl peroxide at 70 ° C constant in hours Hour ' ¹ Acetyl peroxide 8.05 0.086 Propionyl peroxide 4.47 0.155 Decanoyl peroxide 3.40 0.204 Lauroyl Peroxide ..: 3.45 0,201 Benzoyl peroxide 13.0 0.0534 t-butyl peroxyoctoate .... 15.1 0.0458 Di-3-hexoxypropionyl- peroxide 6.82 0.1015

55

60 From Table 1 it can be seen that the new diacyl peroxides described are used as medium-temperature catalysts can be used, but they are with the help of accelerators such as dimethylp-toluidine, even at room temperature z. B. applicable for the cold curing of unsaturated polyesters.

example 1

100 parts by weight of acrylonitrile were hexoxypropionylperoxyd Di-3 with 1 part by weight, _ dissolved in solvent naphtha, mixed and heated under an inert atmosphere at 70 ⁰ C. A white, powdery polymer was obtained after 10 minutes.

Example 2

50 parts by weight of vinyl acetate were mixed with 0.7 parts by weight of 70% di-3-hexoxypropionylperoxydlösung mixed and heated under an inert atmosphere at 6O ⁰ C. ' After 17.3 hours the vinyl acetate solidified to a hard mass; In contrast, the blank sample heated in the parallel experiment remained liquid.

Example 3

50 parts by weight styrene was mixed with 0.7 parts by weight of 70% di-3-hexoxypropionylperoxydlösung mixed and heated under an inert atmosphere for 24 hours 6O ⁰ C. The styrene polymerized to a hard mass; In contrast, the blank sample heated in the parallel experiment remained liquid.

Example 4

100 g of methyl methacrylate-3-hexoxypropionylperoxyd Di mixed with 1 g and 10 g of this mixture in a test tube under an inert atmosphere melted and then heated to 8O ⁰ C. After 1.5 hours, a colorless, crystal-clear molding was obtained.

Example 5

100 g of methyl methacrylate were mixed with 1.0, 0.5 and 0.25 g of di-3-hexoxypropionyl peroxide and 10 g of each mixture were melted in a test tube under an inert atmosphere and then heated ^{to 50 ° C.} Colorless, crystal-clear moldings were obtained after 5, 7 and 8 hours, corresponding to the amount of catalyst indicated above.

Example 6

100 g of methyl methacrylate were mixed with 0.25 g of di-3-butoxypropionyl peroxide or with 0.25 g of a catalyst mixture consisting of 50 percent by weight of di-3-butoxypropionyl peroxide and 50 percent by weight of di-3-hexoxypropionyl peroxide, and 10 g of each of the above methyl Diacylperoxyd mixtures melted in a test tube under an inert atmosphere and then heated to 50 ⁰ C. After 5.5 hours

With di-3-butoxypropionyl peroxide as a catalyst, a colorless, crystal-clear molding was obtained; for the second sample with the mixed catalyst, the polymerization time was 6.5 hours.

Example 7

In this example, the hot curing of a commercially available polyester resin composition according to the process according to the invention is compared with the hot curing that has been customary since then, which uses benzoyl peroxide, t-butyl peroxyoctoate and t-butyl perbenzoate as the catalyst. The tests were carried out according to the generally known SPI method at 82, 100 and 115 ^° C .; the concentration of the peroxides used was 1%, based on the resin composition. The results are shown in Table 2.

Tabel

catalyst

Benzoyl peroxide

t-butyl peroxyoctoate t-butyl perbenzoate

Di-3-hexoxypropionyl peroxide

Di-4-phenoxybutyryl peroxide

Bath temperature, ⁰ C
Gel time (in minutes)

Hardening time
(in minutes) ....

Peak temperature,
⁰ C

colour

82 100 115
3.9 2.2 1.3

5.9 3.4 2.2

82 100 4.3 2.4 0.5

5.9 -3.5 1.5

218 233 235
colorless

211 223 yellowish

The Barcol hardnesses were 40 to 50 units in all tests.

Example 8

This example shows the effect of the invention Diacyl peroxides to be used in the cold curing of unsaturated polyester resin compositions. The procedure was as in Example 7, but using temperatures of 23 to 25 ° C of 0.1 percent by weight of dimethyl-p-toluidine as an accelerator, based on the resin composition. the Results are summarized in Table 3.

Table 3

catalyst Di-3-hexoxypropionyl- peroxide Gel time (in minutes) 37.5 Curing time (in minutes) 47.0 Peak temperature, ⁰ C 137.8 Barcol hardness 45

40

45

5 °

Example 9

The diacyl peroxides to be used according to the invention can be used for curing polyester resin compositions can also be used as mixed catalysts. The results are summarized in Table 4, with the heat curing of a commercially available polyester resin composition according to Example 7 Di-3-butoxypropionyl peroxide alone and with a catalyst mixture consisting of 50 percent by weight Di-3-butoxypropionyl peroxide and 50 percent by weight of di-3-hexoxypropionyl peroxide became. The catalyst concentration was in each case 1 percent by weight, based on the amount of resin.

100 115
10.8 4.6

13.4 5.8

225 240
yellowish

82 100 115
4.2 1.9 0.7

5.6 3.0 1.6

213 222 219
colorless

Table 4

82 100
3.9 2.5

5.7 3.6

208 215
colorless

Bath temperature, ⁰ C
Gel time (in minutes).
Curing time (in minutes)
Peak temperature, ⁰ C
Barcol hardness

catalyst
Di-3-butoxy

propionyl peroxide

Z, ö

3.8
162

Mixed catalyst

82
3.9
4.9
152
45

Claims (2)

Patent claims: 1. Process for the polymerization of olefinically unsaturated organic compounds by means of a polymerization catalyst consisting of a diacyl peroxide, characterized in that the diacyl peroxide a compound of the general formula where A is an alkyl radical or an alkoxyalkyl or phenoxyalkyl radical with preferably 3 to 10 carbon atoms or a phenyl radical, which in turn can be substituted by an alkyl or alkoxy group, and η = 2 or 3, optionally in combination with an accelerator and the polymerization is carried out at temperatures of from about 25 to about 150 ⁰ C. 2. The method according to claim 1, characterized in that the polymerization catalyst used dissolved in inert solvents. Considered publications:
U.S. Patent No. 2,858,326. 809 507/652 1.68 © Bundesdruckerei Berlin