DE2444991A1 - FOAMABLE PLASTIC MIXTURE AND PROCESS FOR THE MANUFACTURE OF FOAMED ARTICLES FROM PLASTICS - Google Patents

Description

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Foamable plastic mixture and method of manufacture of foamed articles made of plastics.

The present invention relates to mixtures of a plastic, a blowing agent and organotin oxides or alcoholates from which objects are foamed in a manner known per se can be produced.

Foamed articles made of plastics have recently gained more and more importance. The objects are in general by known processes, for example the injection molding process, produced by adding a suitable plastic to the plastic Adding blowing agent and choosing the processing temperature so that it is above the decomposition temperature of the Propellant lies.

In the case of many organic compounds, however, their decomposition temperature is too far above the processing temperature, so that they cannot be used alone as propellants. However, they can often be used together with as a kicker designated activators are used, which accelerate the decomposition of the propellant and / or the decomposition temperature

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609814/1134

Managing Director: Dr. Hans Herzog, Chairman Dr. Holger Andreas ■ Business graduate with Günter Schneider

Commercial register:

_ .140

Deutsche Bank AG., Bensheim 12/3000 Dresdner Bank AG., Darmstadt 1 734507

lower the temperature.

Common activators include metal-containing compounds, especially lead, zinc and cadmium compounds.

Lead and cadmium compounds are highly toxic and also give rise to discoloration of hydrogen sulfide. Cadmium and especially zinc compounds also cause catalytic. Decompositions as of polyvinyl chloride (zinc or cadmium ¹¹ burning ").

In DT-OS 2 133 372, an activator system is made up of one Organotin thioglycolic acid ester and a barium soap described. However, barium compounds are also poisonous. the DT-AS 1 258 082 claims a mixture of dibutyltin stearate, zinc oxide and urea as the activator system, the the actual kicker substance is probably zinc oxide.

It has now been found that the long known organotin oxides and alcoholates are excellent activators for organic chemical blowing agents and therefore very good are well suited for the production of foamed plastic articles in the presence of these blowing agents.

The present invention relates to mixtures of a plastic and, if appropriate, further conventional additives, thereby characterized in that in addition to an organic, chemical blowing agent an organotin oxide or alcoholate of the general Formula I or mixtures thereof or hydration or polymerization products

^R n ^SnX 4-n ^(I)

where η denotes the numbers 1 or 2, R denotes identical or different aryl, aralkyl and / or aliphatic radicals and X denotes one equivalent of oxygen or the group 'OR ¹ , in which R ^1, independently of R, has the same meaning as R , optionally together with a solvent for these compounds.

The formula I reproduces these compounds in the simplest monomeric form.

609814/1134

The organotin oxides of the formula I are also dimeric, oligomeric or polymeric organotin oxygen compounds or understood their mixtures. The compounds or mixtures can also contain hydroxyl groups bonded to tin, see above that the term organotin oxides includes organostannonic acids, organotin hydroxides and also about the polystannanediols the DT-PS 838 212 includes.

The organotin alcoholates of the formula I can also be polymers, for example the polystannane diol ethers, as described in of DT-PS 838 212 are described.

In formula I, R preferably represents identical radicals. R also denotes an aliphatic hydrocarbon radical, preferably an alkyl radical with 1 to 12, in particular 1 to 8 carbon atoms, an alkenyl radical with 2 to 12, in particular 2 to 3 carbon atoms and a cycloalkyl radical, especially cyclohexyl. Of the aryl and / or aralkyl radicals is especially phenyl and / or benzyl are preferred. The methyl, butyl, octyl, benzyl and phenyl radicals are particularly preferred.

Examples of alkyl radicals are: methyl, ethyl, n-propyl, i-propyl, η-butyl, i-butyl, pentyl, 2-methylbutyl, 3-methylbutyl, Hexyl, 2-ethylbutyl, heptyl, octyl, 2-ethylhexyl, Nonyl, 2-propylhexyl, decyl, lauryl.

Examples of alkenyl radicals are: vinyl, allyl, 1,2-butenyl, 2,3-butenyl, 1,2-pentenyl, 2-methyl-pentenyl-1,2, hexenyl, 1,2-octenyl, 1,2-dodecenyl. Vinyl is particularly preferred and allyl.

Examples of cycloalkyl radicals are: cyclopentyl, cyclohexyl and derivatives substituted with aliphatic radicals, such as, for example Methylcyclopentyl, dimethylcyclopentyl, methylcyclohexyl, ethylcyclohexyl. Cyclohexyl is particularly preferred.

Examples of aryl radicals are: phenyl, naphthyl and alkyl-substituted such as toluyl, xylyl, ethylphenyl, butylphenyl, octylphenyl, nonylphenyl, dodecylphenyl. Particularly phenyl is preferred.

Examples of aralkyl radicals are: benzyl, phenylethyl, Phenylpropyl, methylbenzyl, butylbenzyl.

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R ¹ has the same meaning as R, but independently thereof, but can contain up to 18 carbon atoms as an alkyl radical.

Preferred alkyl radicals are the methyl, lauryl and stearyl radicals.

The benzyl radical is preferred as the aralkyl radical.

Of the alkylphenyl radicals are the octylphenyl and nonylphenyl radicals preferred.

Thermoplastics in particular are used as plastics in question such as polyesters, polylactones, polyamides, polyethers, polycarbonates and particularly preferably polyolefins. Under the polyolefins polyethylene, polypropylene, polybutene-1, polypentene , Polystyrene, polyacrylates, polyacrylonitrile, polyvinyl chloride, polyvinylidene chloride and copolymers of two or more monomers, e.g. ABS polymers. Polymers made of or based on polyvinyl chloride are particularly preferred, particularly preferably polyvinyl chloride.

Emulsion, suspension and bulk polyvinyl chloride are suitable. Of the copolymers particularly suitable are those which in addition to vinyl chloride from monomers such as vinylidene chloride, transdichloroethane, ethylene, propylene, butylene, maleic acid, Fumaric acid, acrylic acid, itaconic acid, acrylonitrile, butadiene, styrene can be produced.

Suitable organic chemical blowing agents are, for example, in "Kunststoffe, Vol. 62, pages 687 ff.", In "Kunststoffrundschau, 1973, pages 448 ff.", In "Society of Plastics Engineering, 30th Annual Technical Conference (May 15-18th , 1972), part one, pages 486-489 "and in DT-AS 1 295 836. In general, compounds such as peroxides, derivatives däer oxalic acid and nitrogen-containing compounds. In the mixtures according to the invention, blowing agents from the groups urea and related compounds, azo compounds, hydrazine derivatives, semicarbazides, azides, N-nitroso compounds and triazoles are particularly preferred. Into the-

6098H / 1134

Particular preference is given to azodicarbonamide, which is the most important of all propellants because of its wide range of applications has attained.

The organotin oxides can in a well-known manner by hydrolysis the corresponding organotin halides are obtained.

Organotin alcoholates can also be made in a known manner the halides with sodium alcoholate or from the oxides with alcohol. The manufacture of polymeric Alcoholates are described in DT-PS 9> | 5 9 39.

The mixtures according to the invention are prepared by known methods in known mixing devices, e.g. in a tumble mixer or a fluid mixer. You can use the propellant together with the organotin activators add, or mix the activator with a plastic that already contains the propellant or vice versa. To as much as possible To achieve uniform mixtures, it is advantageous to mix the individual components in powder form. However, it is It is also possible to use plastic granules, whereby for better adhesion of the propellant and / or organotin activator a binder can also be used. It is also possible to incorporate the mixture according to the invention of the organotin compounds in a plasticized plastic, e.g. by re-granulating. When applied Of course, higher temperatures must not exceed the decomposition temperature of the blowing agent / activator system will.

For better distribution in the mixture, it is also particularly advantageous in other cases to use solutions of the organotin compounds to be used in suitable solvents for mixing with plastic. A suitable solvent should be used in principle do not contain any reactive groups capable of reacting with the organotin compounds, except are ester groups. Higher-boiling solvents, in particular those with a boiling point of at least 150.degree. C., are preferred.

Particularly preferred solvents are inorganic and organic Esters of oxygen acids, as some of these representatives are mentioned, for example, in DT-PS 9 35 792. When solving the

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Organotin compounds in inorganic or organic esters can interact with the esters, e.g. according to the the aforementioned patent specification and according to DT-AS 1 669 841. The mixtures described there are assumed to be is to present the organotin oxides in equilibrium with the esters. It has been found that the activator effect of the organotin compounds is extremely good compared to a propellant even if they are dissolved in esters. By Dissolving mixtures obtained in inorganic or organic esters of oxo acids are used in the present Invention referred to as solutions.

The organotin compounds in the esters are dissolved by heating the mixture partners to around 140 to 180. In general, up to about 1.2 moles of organotin oxide can be dissolved per mole of ester group. 1 mole of organotin oxide is preferred per mole of ester group. The organotin alcoholates are usually soluble in larger amounts, so that more concentrated ones are also soluble Solutions can be made.

Representatives of inorganic acids on which the esters may be based are described in DT-PS 9 35 792. Preferred are: silicic acid, boric acid and especially phosphoric acids, such as phosphorous acid, phosphoric acid and phosphonic acid.

The organic acids are monofunctional and polyfunctional aliphatic and aromatic carboxylic acids that also contain other functional groups such as -OH, -SH, -COOH and / or -COSH may contain. Examples are:

Aliphatic and aromatic mono- and dicarboxylic acids such as acetic acid, propionic acid, valeric acid, caproic acid, stearic acid, Oleic acid, glycolic acid, lactic acid, thioglycolic acid, thiolactic acid, acrylic acid, vinyl acetic acid, benzoic acid, Phenylacetic acid, oxalic acid, malonic acid, succinic acid, sebacic acid, adipic acid, maleic acid, fumaric acid, phthalic acid, Cyclohexanecarboxylic acid, cyclohexane-1,4-dicarboxylic acid.

The oxygen acids can be mixed with aliphatic and / or aromatic Be esterified alcohols, with polyfunctional alcohols such as glycols, glycerol, trimethylolpropane or Pentaerythritol come into question.

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609814/1134

If reactive groups are still present in the ester, which with the organotin compounds react, these esters can also be used as solvents if the reactive groups be reacted to beforehand. For example, monoesters of dicarboxylic acids can be saturated by salt formation by these esters are converted into the sodium, potassium, magnesium, calcium or aluminum salts in a known manner.

In a particularly advantageous embodiment, reactive Groups such as -OH, -SH, and -COOH are first reacted with an organotin oxide and then an organotin oxide or alcoholate can be dissolved, which can also be done in one process step can be achieved with appropriate amounts of organotin compounds. This is particularly advantageous when using mercaptocarboxylic acid esters and / or maleic acid half esters, their organotin compounds are known effective thermal stabilizers for chlorine-containing thermoplastics, especially for PVC are. Through the measure mentioned, the activator effect can be combined with the stabilizing effect will.

In a further particular embodiment, the organotin compounds dissolved in ester-based plasticizers. Suitable plasticizers are, for example, in "Chemistry, Physics and Technology der Softener ", VEB-Verlag Technik, Berlin, 1960, described. If there is an excess of plasticiser, this can be used at the same time the organotin compounds are mixed with the plastic. Particularly preferred are esters of phosphoric acids, in particular phosphorous acid and phosphoric acid, phthalic acid esters, fatty acid esters, dicarboxylic acid esters and sulfonic acid esters.

Before, during or after the addition of the organotin compounds, further conventional additives can be added to the plastic. These are, for example, fillers, reinforcing fillers such as glass fibers, lubricants, mold release agents, plasticizers, Fillers, modifiers such as impact additives, dyes, pigments, light stabilizers and / or antioxidants.

The amount of organotin compounds in the mixtures according to the invention depends on economic and application technology Points of view. In general, 0.1 to 3

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Percent by weight, based on the plastic, in particular 0.3 to 2 percent by weight added.

The mixtures according to the invention can be prepared by known processes, such as application processes, pressing processes, Injection molding or extrusion are processed into foamed objects made of plastics. Procedures for this are described, for example in "Kunststoffe", 19 74, 1, pages 2-7 and "Kunststoffrundschau", 1973, 10, pages 443-448.

Another object of the present invention is therefore a process for the production of foamed articles from Plastics according to known methods from a mixture containing a plastic, an organic, chemical Propellant, an activator and optionally other customary additives, characterized in that the mixture

a) a compound of the general formula I or mixtures thereof or hydration or Polymerization products, optionally together with a solvent for these compounds

^R n ^SnX 4-n ^(I)

contains as an activator for the propellant, in which n, R and X have the meanings given above have and

b) the mixture is processed above the decomposition temperature of the activator / propellant system will.

The effect of organotin oxides and alcoholates of the formula I as activators for organic chemical blowing agents is surprising, since this effect was found on compounds that have been known for a long time. Finding the activating Property is to be regarded as particularly surprising in view of the fact that other known organotin compounds do not have this effect. The effect is also surprisingly high and these activators are even known activators think. Another particular advantage is that the

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Organotin compounds do not lose this effect in solvents either, which means that they have an activating effect in one wide framework can be coordinated according to application-technical aspects.

The following examples explain the invention in more detail. The parts given herein are parts by weight.

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example 1

2AAA991

100 g of alkaline pre-stabilized E-PVC (K-Wart 70) are mixed with 50 g Dioctyl phthalate, 3 g epoxidized soybean oil, 3 g titanium dioxide and 2 g azodicarbonamide stirred to a paste and coated with 1 g of the activators mentioned in Table 1 in a thickness of 1 mm on a pane of glass and in the temperature range from 165 to 200 with intervals of 5 for 5 minutes each time. The density of the thermally loaded samples is determined. It is a measure of the activating effect. In Table 1, the density is dependent on given by test temperature and activator. The compounds labeled A and B are organotin compounds According to the state of the art.

Table 1 Temp .:
165 ° 170 ° 175 ° 180 ° 185 ° 190 ° 195 ° 200 °

Aj 1.20 1.16 1.10 1.07 0.93 0.83 0.63 0.52

BM 1.17 1.10 1.05 0.97 0.83 0.73 0.49 0.42

Cj 1.09 1.05 0.91 0.71 0.48 0.43 0.32 0.30

Dj '1.13 1.02 0.93 0.74 0.59 0.53 0.42 0.34

E; 1.10 1.01 0.96 0.76 0.61 0.42 0.35 0.33

F; 1.06 0.93 0.78 0.58 0.48 0.40 0.33 0.31

G 11.04 0.94 0.70 0.61 0.55 0.45 0.39 0.35

H j 1.05 0.97 0.81 0.67 0.63 0.48 O> 45 0.40

Ii 1.05 0.97 0.80 0.69 0.56 0.45 0.40 0.34

A = i-octyl dibutyltin bis-thioglycolate B = butyl dibutyltin bis-maleic acid ester

C = solution of 2 mol of dibutyltin oxide and 1 mol of dibutyltin bisß-mercaptopropionic acid i-octyl ester

D = solution of 1.69 mol of dibutyltin oxide, 1.31 mol of dioctyltin oxide and 2 mol of ß-mercaptopropionic acid i-octyl ester

E = solution of 1 mol of dibutyltin oxide and 1 mol of dibutyltin bismaleic acid i-butyl ester

F = solution of 1 mol of dibutyltin oxide and 1 mol of dioctyl phthalate

G = solution of 1 mol of dibutyltin oxide and 1 mol of epox. Butyl oleate

H = solution of 1 mole of dibutyltin oxide and 1 mole of didecylphenyl phosphite

I = solution of 1 mol of dibutyltin oxide and 1 mol of tricresyl phosphate

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Example 2

2U4991

Pastes of the composition shown in Table 2 were placed on a glass support applied with a doctor blade in a thickness of 5 mm and foamed in a gelling oven at 180 °. The foam height was dependent measured from the gel time. The results are shown in Fig. 1.

Basic recipe :

E-PVC, K-value 70-74 40 parts

S-PVC, K-value 64 25 parts

E-PVC, K value 70 35 parts

Butyl benzyl phthalate 26 Tl.

Dioctyl phthalate (DOP) 32 Tl.

Azodicarbonamide 4 Tl.

(50% in DOP)

Chalk 5 tsp.

In addition to the recipe

1) solution of 2 moles of dibutyltin oxide 1 part. And 1 mole of dibutyltin-bis-ßmercaptopropionic acid-2-ethyl-

hexyl ester.

2) epox. Soybean oil 3 parts. Comparative example

liquid Ba / Zn stabilizer, 1 part is more conventional at the same time Kicker. Contains about 8% barium and 3% zinc.

3) Dibutylz: ijm-bis-thioglycolic acid ^ 2- 1 part. " ethylhexyl ester

4) dibutyltin dilaurate 1 part "

5) without stabilizer '"

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Example 3 Gas Elimination Test

10 parts of dioctyl phthalate and 2 parts of azodicarbonamide are mixed with the activator (the amounts are given in Table 2) and kept ^{constant at 190 ° C. in a flask.} The flask is connected to a gas burette and the amount of gas evolved is read off at certain times. With this experimental set-up, the effect of the activators can be easily measured.

In Table 2, the amount of gas in ml is based on 1 g of azodicarbonamide specified.

Numbers 21-27 are comparative tests.

Table 2

Min. 1 26th
26th 2 26th
33 3 26th
33 4th 52
91 5 ^l 6 7th 26th
33 8th 189
189 9 ■ 10 11 169
228 12th 13th 0.5
1 33
33 39
52 39
39 156
221 26 26
33 26 59
150 26th
26th 189
189 26 26
33 33 26th
39 195 241 228
195 241 228 26th
26th 33
29 1.5
2 39
¹ 45 143
228 65
111 241
247 46 33
98 46 33
52 189 39 72 130
65 117 156 195241 228
195 ^! 241 228 33
39 45
52 2.5
3 59
^: 234 260
260 130
234 247
247 156 78
202 111 202 85
2151143 98 234
195 234 195 241 228 65
117 58
78 3.5
4th J 312
I 312 260
260 234
234 254
254 2O8 ^! 143
208; 189 215
215 130
221 117
221 4.5
5 '312 260 241 267 208; 208
208, 208 215
215 221
221 221
221 10 208 208 215 221 221

Min.

14 15 16 17! 18 | 19 20

21 ' 22nd 23 24 25th 26th 27 26, 26th 26th 26th 26th 26th 26th 26 y 26th 26th 26th 33 26th 33 29: 26th 29 33 46 39 52 29: 29 29 33 65 46 189

26th
26th

39
65

124
286

293
293

293
293

26th
33

39

26th
33

78 1130

143; 176
195 ι 247.

241! 247 '
241,247;

241 ί 247;

241 ^! 247 '

26 33

39! 52!

26 I 26; 33 j 26:

39 65 ι

111, 124 143 | 143

169 j 169

221 241

254! 241

33 46;

59 78

91 124

241

306 248: 247

254 241; 241 254 241 241

26 26

39 78

104 117

143 286

286 286

2 86

29; 33
33: 33

33
36

33. 42, 46
33 j 52; 59

33 I 72'i11
33 156 189

39
46

52
65

78
98

70 72 j 189

78 215! 189

78 i215I 195

78215 195

85 '215

195

! 52 182 189 195

85 215 195 195 221: 2p1

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To table

No parts

0.4 1

0.4 1 1 1

Dimethylζ innoxid Dibutyltinnoxid Dibutyltinnoxid Bis-methoxy-dibutyltin bis-lauryloxy-dibutyltin Bis-stearyloxy-dibutyltin bis-benzyloxy-dibutyltin Bis-octylphenyloxydibutyltin bis-nonylphenyloxydibutyltin Monobutyl tin oxide (butyl stannonic acid) Dineopentyl tin oxide, dioctyl tin oxide Monooctyltin Oxide (Octylstannonic Acid)

1.2

Solution of 1 mole of dibutyltin oxide and

1 mole of dibutyltin bis-maleic acid methyl ester

Solution of 2 moles of dibutyltin oxide and

1 mole of isooctyl dibutyltin bis-ß-mereaptopropionate

Solution of 4 moles of dibutyltin oxide, 1 mole of dioctyl phthalate and

1 mole of isooctyl dibutyltin bis-ß-mercaptopropionate

Solution of 1 mole of dibutyltin oxide and 1 mole of dioctyl phthalate

Solution of 1 mole of dibutyltin oxide and 1 mole of epox. Butyl oleate

Solution of 1 mol of dibutyltin oxide and 1 mol of phenyl didecyl phosphite

Solution of 1 mole of dibutyltin oxide and 1 mole of tricresyl phosphate

without activator isooctyl dimethyltin bis-thioglycolate Isooctyl dibutyltin bis-thioglycolate Dibutyltin-bis-lauryl mercaptide tributyltin oxide (oxy-bis-tributyltin, see

DT-AS 1 295 836, column 6, below)

Barium zinc activator, 8% Ba and 3% Zn lead activator, 27% Pb

6 09814/1134

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Claims (1)

Expectations 1. Mixtures of one plastic and possibly others usual additives, characterized in that in addition to an organic, chemical blowing agent an organotin oxide or alcoholate of the general formula I or mixtures thereof or hydration or polymerization products ^R n ^SnX 4-n ^(I) where η denotes the numbers 1 or 2, R denotes identical or different aryl, aralkyl and / or aliphatic radicals and X denotes one equivalent of oxygen or the group OR ¹ , in which R ^1, independently of R, has the same meaning as R, is optionally included together with a solvent for these compounds. 2. Mixtures according to claim 1, characterized in that a thermoplastic material is contained. 3. Mixtures according to claim 2, characterized in that a polyolefin is included. 4. Mixture according to claim 3, characterized in that a polyolefin made of or based on polyvinyl chloride is included. 5. Mixture according to claim 1, characterized in that it contains azodicarbonamide as blowing agent. 6. Mixture according to claim 1, characterized in that R in formula I represents the same radicals. -15- 609814/1134 7. Mixture according to claim 1, characterized in that R ¹ in the group X represents the same radicals. 8. Mixture according to claim 1, characterized in that R in formula I is an alkyl or alkenyl radical with 1-12 Carbon atoms. 9. Mixture according to claim 1, characterized in that R in formula I stands for the vinyl or allyl radical. 10. Mixture according to claim 1, characterized in that R in formula I stands for the phenyl or benzyl radical. 11. Mixture according to claim 1, characterized in that R in formula I represents the cyclohexyl radical. 12. Mixture according to claim 1, characterized in that R in formula I represents the methyl, butyl or octyl radical. 13. Mixture according to claim 1, characterized in that the compound of formula I contains dibutyltin oxide. 14. Mixture according to claim 1, characterized in that ■ is contained as a compound of the formula I dioctyltin oxide. 15. Mixture according to claim 1, characterized in that as a compound of formula I dimethyltin oxide is included. 16. Mixture according to claim 1, characterized in that as a compound of the formula I monobutyltin oxide and / or butylstannonic acid is included. 60 9 8 U / 1134 ~ ¹⁶ " 17. Mixture according to claim 1, characterized in that the compound of formula I contain bis-methoxydibutyltin is. 18. Mixture according to claim 1, characterized in that as Compound of the formula I contain bis-lauryloxydibutyltin is. 19. Mixture according to claim 1, characterized in that the compound of formula I contain bis-stearyloxydibutyltin is. 20. Mixture according to claim 1, characterized in that the compound of formula I contain bis-benzyloxydibutyltin is. 21. Mixture according to claim 1, characterized in that the compound of formula I contains bis-octylphenyloxydibutyltin is. 22. Mixture according to claim 1, characterized in that the compound of formula I contain bis-nonylphenyloxydibutyltin is. 23. Mixture according to claim 1, characterized in that inorganic or organic esters of oxygen acids are contained as solvents which have no other reactive groups with respect to the compounds of the formula I own. 24. Mixture according to claim 23, characterized in that it contains ester-based plasticizers. 25. Mixture according to claim 24, characterized in that it contains esters of phosphoric acids. 26. Mixture according to claim 24, characterized in that phthalic acid or adipic acid esters are included. 609814/1134 27. Mixture according to claim 24, characterized in that it contains esters of fatty acids. 28. Mixture according to claim 1, characterized in that Esters of mercaptocarboxylic acids or maleic acid half esters are included, their reactive groups with an organotin oxide are implemented. i Process for the production of foamed articles K ^ y from plastics according to known processes from a mixture containing a plastic, an organic, chemical blowing agent and an activator and optionally further conventional additives, characterized in that the mixture .a) a compound of the general formula I or its Mixtures or hydration or polymerization products, _ _n (I) optionally together with a solvent for these compounds as an activator for the propellant contains, wherein n, R and X have the meaning given in claim 1 and b) the mixture is processed above the decomposition temperature of the activator / propellant system. 30. Foamed articles made of plastics, manufactured according to Claim 29. 609 8 14/1134 Blank page