DE1065172B - Process for the production of foam bodies based on organopolysiloxane resin - Google Patents

Description

GERMAN

PATENT OFFICE

kl. 39 b 22/10

INTERNAT. KL. C 08 g

D26620IVb / 39b

REGISTRATION DATE: OCTOBER 11, 1957

NOTICE THE REGISTRATION AND ISSUE OF THE EDITORIAL:

SEPTEMBER 10, 1959

The subject of the main patent is a process for production that can be carried out at room temperature of foam bodies based on organopolysiloxane resin by hardening certain organosiloxane resins with the help of quaternary ammonium hydroxides, alkoxides, quaternary ammonium salts of certain aliphatic carboxylic acids or of alkali metal alkoxides.

It has now been found that, instead of the curing catalysts mentioned, also up to 30 percent by weight, calculated on the amount of polysiloxane, quaternary ammonium salts of silanols, alkali silanolates, Alkali siloxanolates, alkali metal hydroxides and / or carboxylic acid salts of tin and lead as curing catalysts can be used, while all other components and proportions of the according to the mixture used in the main patent remain unchanged.

The curing catalysts effective according to the invention have the common feature that they are rapid Generate hydrogen evolution at room temperature. They can be added as such or they can be included situ can be generated. The catalysts are preferably calculated in amounts of 1 to 10 percent by weight applied to the siloxane weight. The appropriate amount of catalyst generally depends on the SiH concentration from. At higher SiH concentrations less catalyst is required.

All quaternary ammonium salts of silanols of the formulas R ₃ SiONR ₄ ', siloxanols process, can be used as catalyst

for the production of foam bodies based on organopolysiloxane resin

Addendum to patent 1,017,366

R ₄ 'N - O— VSiCVsNR ₄ '
RSi (ONR ₄ ') _M O ₃ _ _n ,

wherein R represents an optionally halogenated monovalent hydrocarbon radical or halophenoxymethyl radical and η has a value from 1 to 3 inclusive; any alkali metal salt of silanols and siloxanols, any alkali metal hydroxide and any carboxylic acid salt of tin or lead.

Examples of organic radicals which are substituted on the Si atom of the above-mentioned catalysts are monovalent hydrocarbon radicals such as alkyl radicals, e.g. B. methyl, ethyl and octadecyl radicals, Alkenyl radicals, e.g. B. vinyl, allyl and hexenyl radicals, cycloaliphatic radicals, e.g. B. Cyclopentyl, cyclohexyl and cyclohexenyl, aryl, e.g. B. phenyl, toluyl, xenyl and naphthyl radicals, alkaryl radicals, e.g. B. benzyl radicals. The R residues can also be any halo applicant:

Dow Corning Corporation, Midland, Mich. (V. St. A.)

Representative: L. F. Drissl, lawyer, Munich 23, Clemensstr. 26th

Claimed priority: V. St. v. America October 15, 1956

Donald E. Weyer, Midland, Mich. (V. St. A.), has been named as the inventor

be emitted monovalent radicals, such as chloromethyl, trifluorovinyl, Chlorotrifluorocyclobutyl-, α, α, α-trifluorotoluyl-, Chlorophenyl, bromoxenyl, pentafluoroethyl and pentafluoropropenyl radicals. Finally, the R residues can too Halophenoxymethyl radicals, such as pentachlorophenoxymethyl, dibromophenoxymethyl and trichlorophenoxymethyl radicals.

In the quaternary ammonium radicals, R 'can be any aliphatic hydrocarbon radical such as the methyl, ethyl, butyl and octadecyl radical, any alkenyl radical such as the vinyl, allyl and hexenyl radical, any cycloaliphatic hydrocarbon radical such as the cyclohexyl, Cyclopentyl and cyclohexenyl radical, any aromatic hydrocarbon radical, such as the phenyl, xenyl and toluyl radical, any aralkyl hydrocarbon radical, such as the benzyl or / I-phenylethyl radical, and any hydrocarbon radical containing oxy groups, such as the oxyethyl, oxypropyl, oxy , Oxyphenyl or oxyhexenyl radical.

Any substances are suitable as alkali metal hydroxides and alkali metal salts of silanols and siloxanols of this type can be used according to the invention. Examples are: lithium, rubidium and cesium

909 627/430

hydroxyd, the sodium salts of monoethylsiloxanols, ζ. Β.

C ₂ H ₆ SiONa,

C ₈ H ₆ Si (ONa) ₂

C ₂ H ₅ Si (ONa) ₃ ,

of phenylvinylsiloxanols, e.g. B.

NaO (C ₈ H ₆ SiO) ^ Na,

CH

I!

CH ₂

wherein χ is at least 1., and of toluyldivinylsiloxanol, z. B.

(CH = CH ₂ ),

CH _; , C _e H ₄ SiONa,

the potassium salts of monocyclohexenylsilanol, octadecylallylsilanol and tri- (2-ethylhexyl) -silanol, the lithium salts of 1,1,1-trifluoropropylsilanol, naphthylbutylsilanol and dicyclopentylbenzylsilanol, the rubidium salts of vinylsilanoi, phenylmethylsilanol and Phenylvinylmethylsilanol and the cesium salts of Dibromophenoxymethylsilanol, Diphenylsilanol and Bromoxynylcyclohexylhexenylsilanol.

Any carboxylic acid salts of tin and lead or their organometallic derivatives are also effective according to the invention, z. B. lead diacetate, lead acetate, dibenzoate, diisobutyrate and melissate, tin citrate, dicaprate and almondate, carbometlioxyphenyl tin trisuberate, Isobutyl tin triccroat, cyclohexenyl lead triacotinate, Xenyl lead trisalicylate, dimethyl tin butyrate, divinyl tin - biscyclopentylacetat, diisoamyltin - biscyclobenzoate, Diphcnyl lead diformiate, dicyclopentyl lead monochloroacctate, Dibenzyl lead di-2-pentenoate, diallyl lead di-2-hexenoate, Triethyl tin bitartrate, tricyclohexyl tin vinyl acetate, Tritolyl tin terephthalate, tri-n-propyl lead acetate, tristearyl lead succinate, tnnaphthyl - lead - methyl benzoate, triphenylethyl-leadicyclohexenyl acetate, and half ester salts of carboxylic acids, e.g. B. Triphcnyl-lead-ethyl malonate.

As a third component containing hydroxyl groups, in addition to those already mentioned in the main patent Compounds also include an alkali metal hydroxide, such as. B. sodium oxide, can be used.

If necessary, various other constituents can be added to the foamable compositions, such as fillers, flame retardants, stabilizers, plasticizers such as silicone oils. Suitable fillers are powdered metals such as aluminum, tin and zinc, as well as powdered silicon, silica, mica, clay and metal oxides such as iron oxide. Antimony oxide, calcium carbonate, polychloricrtc are suitable as flame retardants Hydrocarbons such as highly chlorinated biphenylc and highly chlorinated paraffin oils as well as organic ones Sulfamates.

Additional catalysts can also be used to improve the hardening of the resin. these can any conventional catalysts commonly used in siloxane resins, such as other than that metal salts of carboxylic acids or amines used according to the invention.

It is often expedient to use the organopolysiloxane together with a solvent, and especially when the polysiloxane is solid per se. Suitable solvents are e.g. B. hydrocarbons, such as benzene, toluene, xylene, petroleum hydrocarbons and chlorine-containing solvents such as methylene and ethylene chloride.

The foams obtained are distinguished by a uniform pore structure and uniform density.

ίο pore size and density can be changed with the help of the amount of Hydrogen organopolysiloxane can be changed in relation to the amount of catalyst. Generally will the denser foams with lesser amounts and the lighter foams with larger amounts of silicon-bonded Obtained hydrogen-containing polysiloxanes. The density of the foam increases at a rapid rate Hydrogen evolution low. This can also be achieved by changing the amount of catalyst and / or Hydroxyl compound increased in the system. In general, the density varies according to the invention obtained foams between 0.048 and 0.48, although more or less dense products are also produced can be.

The foams according to the invention are suitable, for example, for thermal insulation for pumps, motors, Pipe systems, firewalls and other devices and as reinforcement material of light weight for structural parts.

The experiments according to the following example were carried out exclusively at room temperature.

example

The mass used for the production of foam bodies contains a mixture of 80 g of about 3 percent by weight silicon-bonded hydroxyl group-containing copolymer of 25 mol percent monomethylsiloxane, 20 mole percent dimethylsiloxane, 35 mole percent monophenylsiloxane and 20 mole percent diphenylsiloxane, 20 g of methylene chloride solvent and a mixture of 4 g of mixed cyclic methylhydrogen polysiloxanes and 4 grams of a trimethylsiloxy endblocked phenylmethylsiloxane oil. This Mixture, a catalyst is added in each case in the amount specified in the table below, whereby the foam body described in each case is formed after standing at room temperature.

Tabel

catalyst

(CH ₃ J ₃ SiONa, dissolved in 4 g of toluene
Lead-2-ethylhexoate, in 4 g of toluene

solved

(C ₄ H _e ) ₈ Sn (OCOCH ₃ ) ₂

(C ₄ H ₉ ), Sn (O COC ₁₁ H ₂₃ ),

Tin octoate

Tin oleate

NaO [(CH ₃ J ₂ SiO] ₃ Na (powder) ..
KO [(CH ₃ J ₂ SiO] ₂ K (powder) ...

KOH (powder)

NaOH (powder)

CH ₃ SiO (ONa) ₃ , (powder)

4 4 4 4 4 2 2 2 2 2

Density of

Foam-

body in

g / ocm

0.24030

0.19224 0.41972 0.36045 0.38928 0.33802 0.09804 0.08081 0.28836 0.22428 0.22908

When using carbomethoxyphenyl lead

octoate, dibutyltin dibenzoate, lead suberate, the benzyltrimethylammonium salt of dimethylsiloxanol, the / 5-hydroxyethylammonium salt of monophenylsiloxanol, the cesium salt of methylphenylsiloxanol or of

Claims (1)

5 6 the lithium salt of monoethylsiloxanol individually or in 1017 366, characterized in that as Combination instead of the curing catalyst listed in the table up to 30 percent by weight, Catalysts are also made foam bodies. calculated on the organopolysiloxane weight quaternary ammonium salts of silanols or Iatent claim: ₅ siloxanols, alkali metal salts of silanols or Process for the production of foam bodies siloxanols, alkali metal hydroxides and / or car- on an organopolysiloxane resin basis according to the patent used bonsäuresäuresalzen of tin and lead. © 909 627/430 9. 59