NO135598B - - Google Patents

Description

Cellular polyurethane plastic.

The invention relates to cellular polyurethane plastic and more particularly to a

correct method for simultaneously catalyzing the reaction that leads to its formation and stabilizing the formation of the resulting cellular lattice.

The production of cellular polyurethane plastic from organic substances which predominantly contain primary hydroxyl groups, such as hydroxyl polyesters, is well known. The primary hydroxyl groups rea-

randomly generates rapidly with organic polyisocyanates, so that the polymerization reaction will take place at the same time as the gas production reaction between an organic

nic polyisocyanate and water to give a cellular lattice. It is necessary to modi-

fissile many organic compounds containing hydroxyl groups to incorporate primary hydroxyl groups into them. This is particularly the case with polyhydric polyalkylene ethers which are produced by condensation of alkylene oxides such as e.g. propylene oxide. The secondary hydroxyl group is not as reactive with an organic polyisocyanate as a primary hydroxyl group. Furthermore, the compounds with secondary hydroxyl groups generally have a la-

be viscosity, which makes it more difficult to mix them with organic

low polyisocyanates. Consequently, it is difficult to adjust the degree of reaction between an organic polyisocyanate and an organic compound containing secondary hydroxyl groups with the degree of the gas-producing system, leading to a cell

met product, so that the two are matched

against each other to form a cellular lattice. It is also known that certain strong catalysts such as endomethylene piperazine and heavy metal salts will catalyze reactions

nen between a secondary hydroxyl group and an organic polyisocyanate. The use of these catalysts alone suffers from the disadvantage that the resulting product cannot acquire satisfactory physical properties.

per. In some cases, voting is postponed

gene of the reaction to the extent that the reaction product undergoes an initial rise to form a cellular pro-

duct and then collapse.

It is the object of the invention when producing foams on an isocyanate basis from polyhydroxyl and/or polycarboxyl compounds, polyisocyanates and possibly water in the presence of tin compounds to use silicone compounds, which contain 4-valent tin, and in which each tin atom over Sn-C bonds is connection

that with 1-3 organic radicals.

From German patent no. 964 988, tin-form compounds are known as additives in the production of isocyanate-based foams. However, these tin compounds are not catalysts,

but about pore regulators and not about tin compounds, in which the tin atom is directly bonded to a carbon atom. With the present tin compounds, not only is the foaming process catalyzed and

mes on each other, but the foam formed

substance is simultaneously stabilized. The tin compounds also show a tendency towards hydrolysis during the production of the foam,

so that the risk of acid corrosion does not exist. Also considered on their own, these compounds show no tendency to split when stored and used in foam processes. As they are also odorless and harmless, they facilitate handling from a pre-processing technical point of view.

Polyhydroxy compounds which entirely or for the most part contain secondary hydroxyl groups are preferably suitable for carrying out the method according to the invention. Examples include pure polymers of alkylene oxides such as propylene oxides, butylene oxides, styrene oxide, epichlorohydrin or also the addition products of these oxides with di- or polyhydric alcohols and phenols such as with ethylene glycol, polyethylene glycols, alkanediols and alkanetriols, alkenediols, alkynediols, pentaerythritol . , di-ethylenetriamines, aniline, piperazine with amino alcohols with at least two active hydrogen atoms such as methanolamine, N-alkyl-ethanolamine, diethanolamine, N-alkyldieta-nolamih, triethanolamine with polyesters having at least two OH groups such as castor oil, or also on other compounds with more active hydrogen atoms, such as on sugar. During the polycondensation of the oxides, ethylene oxide can also be partially co-condensed or subsequently condensed. Although the resulting polyhydroxy compounds at lower ethylene oxide content do not differ significantly from the above-mentioned polyhydroxy compounds with regard to their reactivity towards polyisocyanates. Polyhydroxy compounds with. secondary hydroxyl groups can also be produced by esterification of one or more of the above-mentioned polyalcohols which partially contain secondary hydroxyl groups with deficit amounts of the aqueous polycarboxylic acids such as succinic acid, adipic acid, sebacic acid, di- and trimerized fatty acids, phthalic acids, maleic acids, or fumaric acids, as by co-using amino alcohols, tertiary nitrogen atoms or carbonamide groups can be incorporated into the polyester at the same time. Alongside the preferably suitable polyhydroxy compounds with secondary hydroxyl groups, such polyhydroxy compounds can of course also be used if the hydroxyl groups are of a primary nature. Such polyhydroxy compounds can, e.g. are obtained by esterification of the primary polyalcohols listed above or also amino alcohols with the polycarboxylic acids already listed. Furthermore, this group also includes the most diverse types of polyesters, such as e.g. are derived from ethylene glycol, tetrahydrofuran or also thiodiglycol or also the most diverse polyacetals.

The linear or branched polyhydroxy compounds used for the production of the foam must, if they are derived from polyesters, have an acid number of less than 15. All types must have an OH equivalent. of preferably 100-3000, whereby OH-equivalent is to be understood as the amount of polyhydroxy compound in grams that contains 1 mol of hydroxyl groups. The listed polyhydroxy compounds can be mixed in the desired way during the formation of the foam, in addition, e.g. the already mentioned low molecular weight polyhydroxy compounds are added, however, the OH equivalents must also be between 100 and 3000 for the mixture.

As polyisocyanates, desirable aliphatic, araliphatic or aromatic polyisocyanates can be used in the method according to the invention, such as tetramethylene diisocyanate, hexamethylene diisocyanate, phenylene diisocyanate, the toluyl diisocyanates, 4,4'-diphenylmethane diisocyanate or the like, or also the addition products of these polyisocyanates on deficit amounts of low-molecular alcohols such as glycerin, trimethylolpropane, the hexanediols and hexanetriols or also on low-molecular polyesters such as castor oil. Furthermore, the reaction products of the above-mentioned multivalent isocyanates with acetals, as well as the e.g. isocyanate polymers mentioned in the German patents no. 1,002,789 and 1,027,394, since of course desirable mixtures can also be used in this case. The method can also find a further application in the foaming of the above-mentioned polyhydroxy compounds and excess polyisocyanate obtained "pre-adducts" caused by the addition of water.

Any suitable silicone compound containing tetravalent tin having direct Sn-C bonds may be used in accordance with the method of the invention. In order to form the stabilization effect, the silicone compounds containing tetravalent tin, which have direct Sn-C bonds, should contain at least one siloxane chain in the molecule. In other words, the catalyst stabilizers according to the invention must be organotin compounds containing a siloxane chain. Silane bonds or free siloxane atoms may also be present. Furthermore, the silicone compounds according to the invention can have attached any suitable organic radical such as, for example those mentioned more specifically below. The tin atoms are usually incorporated into the molecule by means of Sn-O-Si bonds, and they may also be substituted with any suitable organic radical. The organic radicals for substitution on the silicon atom or the tin atom can e.g. be aliphatic, aromatic or heterocyclic radicals.

The organic radicals can be substituted with any substituent which does not affect the catalytic activity of the silicone compound containing tin, such as, for example halogen, such as chlorine, bromine, iodine, fluorine and the like; n.itro; alkoxy such as e.g. methoxy, ethoxy, propoxy, butoxy, amoxy and the like; carboalkoxy such as e.g. carbomethoxy, carboethoxy and the like; dialkylamino such as e.g. dimethylamino, diethylamino, dipropylamino, methylethylamino and the like; mercapto; carbonyl; thiocarbonyl; hydroxy; phosphate; phosphoryl and the like.

When aliphatic radicals are the organic radicals, they can e.g. be alkyl, alkenyl, aralkyl and/or aralkenyl.

Any suitable alkyl radical can be the organic radical, such as e.g. methyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, n-amyl and various isomers of these such as e.g. 1-methylbutyl, 2-methylbutyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl, 2,2-dimethylpropyl, 1-ethylpropyl and the like and the corresponding unbranched and branched isomers of hexyl, heptyl, octyl, nonyl, decyl, undecyl , dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nondecyl, eicosyl and the like.

Any suitable alkenyl radical can be the organic radical such as e.g. ethenyl, 1-propenyl, 2-propenyl, iso-propenyl, 1-butenyl, 2-butenyl, 3-butenyl and the corresponding branched isomers thereof, such as e.g. 1-isobutenyl, 2-isobutenyl, 1-sec.-butenyl, 2-sec.-butenyl, including 1-methylene-2-propenyl, 1-pentenyl, 2-pentenyl, 3-pentenyl, 4-pentenyl and the corresponding branched chain isomers thereof; 1-hexenyl, 2-hexyl, 3-hexenyl, 4-hexenyl,. 5-hexenyl and the corresponding isomers with branched chains thereof, such as e.g. 3,3-dimethyl-1-butenyl, 2,3-dimethyl-1-butenyl, 2,3-dimethyl-2-butenyl, 2,2-dimethyl-3-butenyl, l-methyl-l-ethyl- 2-propenyl and the various isomers of heptenyl, octenyl, nonenyl, decenyl, undecenyl, dodecenyl, tridecenyl, tetradecenyl, pentadecenyl, hexadecenyl, heptadecenyl, octadecenyl, nondecenyl, eicosenyl and the like.

Any suitable aralkyl radical can be the organic radical, such as e.g. benzyl, a-phenyl-ethyl, (3-phenylethyl, «-phenyl-propyl, p-phenylpropyl, gamma-phenylpropyl, a-phenyl-isopropyl, p-phenylisopropyl, a-phenylbutyl, (3-phenylbutyl, gamma-phenylbutyl, delta-phenylbutyl, «-phenyl-isobutyl, (3-phenyl-isobutyl, gamma-phenyl-isobutyl, a-phenyl-sec.-butyl, p--phenyl-sec.-butyl, gam-ima-phenyl-sec. butyl, p-phenyl-t-butyl, cT-naphthyl-methyl, p'-naphthyl-methyl and the corresponding a'-and (3'-naphthyl derivatives of n-amyl and the various positional isomers of these, e.g. 1 -methyl-butyl, 2-methyl-butyl, 3-methyl-butyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl, 2,2-dimethyl-propyl, 1-ethylpropyl and said derivatives of the corresponding isomers of hexyl, heptyl, octyl and the like, including eisocyl and the corresponding alkyl derivatives of phenanthrene, fluoroene, acenaphthene, chrysene, pyrene, triphenylene, naphthacene and the like.

Any suitable aralkenyl radical can be the organic radical such as e.g. a-phenyl-ethenyl, p-phenyl-ethenyl, a-phenyl-l-propenyl, p-phenyl-l-propenyl, gamma-phenyl-l-propenyl, a-phenyl-2-propenyl, p-phenyl-2- propenyl, gamma-phenyl-2-propenyl, p-phenyl-isopropenyl and phenyl derivatives of the isomers of butenyl, pentenyl, hexenyl, heptenyl up to and including eicosenyl and other aromatic derivatives of alkenyl, i.e. alkenyl radicals derived from naphthalene, phenanthrene, fluorene, acenaphthene, chrysene, pyrene, triphenylene, naphthacene and the like.

Any suitable cycloalkyl radical can be the organic radical, such as e.g. cyclopropyl, cyclobutyl, cycloamyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, cycloundecyl, cyclodecyl, cyclotridecyl, cyclotetradecyl, cyclopentadecyl, cyclohexadecyl, cycloheptadecyl, cyclooctadecyl, cyclonondecyl, cycloloeicosyl, n-cyclopropylethyl, p-cyclopro-propyl-ethyl, a-cyclobutylpropyl, p-cyclobutyl-propyl, gamma-cyclobutyl-propyl, a-cycloamyl-isopropyl, p-cycloamylisopropyl and the like.

Any suitable cycloalkenyl radical can be the organic radical, such as e.g. α-Cyclohexylethenyl, β-Cyclohexylethenyl, o-Cycloheptyl-1-propenyl. p-cycloheptyl-1-propenyl, gamma-cycloheptyl-1-propenyl, α-cyclooctyl-2-prope-liyl, gamma-cyclooctyl-2-propenyl, p-cyclo-nonylisopropenyl, α-methylene-p-cyclodode-cyl- ethyl and the like.

Any suitable aryl radical can be the organic radical such as e.g. phenyl, α-naphthyl, (3-naphthyl, α-anthryl, (3-anthryl, gamma-anthryl including the various monovalent. radicals of indene, isoindene, acenenaphthene, fluorene, phenanthrene, naphthacene, chrysene, pyrene, triphenylene and the like.

Any suitable alkaryl radical may be the organic radical, such as e.g. o-tolyl, m-tolyl, p-tolyl, 2,3-xylyl, 2,4-xylyl, 2,5-xylyl, 2,5-xylyl, 2,6-xylyl, 3,4-xylyl, 3, 5-xylyl, o-cumenyl, m-cumenyl, p-cumenyl, mesityl, o-ethylphenyl, m-ethylphenyl, p-ethylphenyl, 2-methyl-a-naphthyl, 3-methyl-a-naphthyl, 4-methyl- a-naphthyl, 5-methyl-a-naphthyl, 6-methyl-a-naphthyl, • 7-methyl-a-naphthyl-8-methyl- -a-naphthyl, 1-ethyl-p-naphthyl, 3-ethyl- (3-naphthyl, 4-ethyl-|3-naphthyl, 5-ethyl-p-naphthyl, 6-ethyl-p-naphthyl, 7-ethyl-p-naphthyl, 8-ethyl-p-naphthyl, 2,3- di-propyl-α-naphthyl, 5,8-diisopropyl-p-naphthyl and the like.

Any suitable heterocyclic radical can be the organic radical, such as e.g. furfuryl, pyryl, and the like.

Higher-valent radicals are those derived from bivalent and higher-valent polyhydroxy compounds, such as ethylene glycol, diethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycols, polytetrahydrofuran and mixed polyesters thereof, glycerol, trimethylolpropane, trimethylolethane, pentaeryltritol, hexitol and the carboxylation products thereof polyalcohols.

The tin-containing silicone compounds used according to the invention can be regarded as comprising essential building blocks of the following types:

in which m and n mean 1, 2 or 3, since to a certain extent m and n can also be 0, R and R' are monovalent organic radicals as indicated above, R" are higher valent organic radicals, derived from the polyhydric alcohols indicated above , the hydrogen and half of the oxygen having been removed in each of the hydroxyl groups. The tin-containing silicone compounds therefore include those having periodic groups

where a and c are whole numbers and b is whole numbers including 0.

The tin-containing silicone compound can be prepared in accordance with known methods. They can e.g. is produced by transesterification of the silanol compound containing a -Si-OH group with a

IN

Alkoxy-tin compound with the formula RnSn(OR')4ll, in which R is an organic radical as defined above, and n is an integer from 1 to 3, ROH being split off in the reaction. In addition, the stabilizer catalyst according to the invention can be prepared by reacting a silanol salt such as the sodium salt of trimethylsilanol with a tin halide of the formula RnSnX4 n, in which R is an organic radical as defined above, n is an integer from 1 to 3 and X is halogen such as chlorine, bromine, iodine, as the metal halide is split off. Furthermore, the catalysts can be prepared by bringing an alkoxysilane such as trimethylmethoxysilane or an alkoxysiloxane such as polydimethylmethoxysiloxane containing -Si-OR groups, in which R has

the indicated meaning as above, for reaction with tin halide of the formula RMSnX4 n, in which R, n and X have the above meaning, or for reaction with tin acylate of the formula R„Sn(OCOR)4„, in which R is an organic radical as indicated above, as an alkyl halide, such as e.g. ethyl chloride, benzyl chloride, chlorobenzene and the like or an alkyl ester such as e.g. acetoacetic acid esters or other esters with the formula ROCOR, in which R is an organic radical as stated above, are split off in the reaction. The latter reactions can preferably be carried out in the presence of a catalyst such as e.g. acetyl chloride. The tin-containing silicone compounds according to the invention can also be prepared by bringing a halosilane or a halosiloxane such as e.g. trichloromethyl silane, polydichloromethyl silane and the like for reaction with an alkyl tin acylate, such as e.g. dibutyltin diacetate, the corresponding acyl halide being split off. The tin-containing part of the molecule can be bound to the siloxane part through -Sn-C-O bonds in a simple way by the transesterification of alkoxytin compounds of the following formula, e.g.

RMSn(OR)4 „, in which R and n are as indicated above with a silane or siloxane containing free hydroxyl groups and a carbon atom and which in turn is bound to a silicon atom either directly or through ether oxygen bridges or by reaction of the corresponding alcoholate with tin halide under anhydrous conditions.

The silanes and siloxanes to be used in the production of the tin-containing silicone compounds can be derived from monomers with the general formula R^iX^, in which n is 0, 1, 2 or 3, R is an organic radical as specified above and x represents a hydroisable group, such as a halogen atom, such as chlorine, bromine, iodine and the like, an amino group or an alkoxy group such as methoxy, ethoxy, propoxy, butoxy, amoxy and the like. If desired, hydrocarbon radicals and/or hydrocarbon radicals connected by ether oxygen atoms can be incorporated into the silicone part of the molecule by condensation of the previously mentioned silane compounds in the presence of a polyhydric alcohol or alkylene oxide. The silicone compounds which have terminal hydroxyl groups in the molecule can be obtained by using an excess of the polyhydric alcohol or the alkylene oxide. Suitable polyhydric alcohols are e.g. ethylene glycol, propylene glycol, butylene glycol, glycerin, trimethylolpropane, polyethylene glycols, polypropylene glycols and the like. The alkylene oxides that can be used are e.g. ethylene oxide, propylene oxide, butylene oxide, epichlorohydrin, styrene oxide and the like, as well as reaction products thereof with polyhydric alcohols such as e.g. glycerin, trimethylolpropane, 1,3,6-hexanetriol, castor oil, sugar and the like. The silicone compounds can also be modified to contain monofunctional alkoxy radicals of higher molecular weight by reaction with e.g. a higher alcohol such as stearyl alcohol, or with addition products of the previously mentioned alkylene oxides with monofunctional alcohols or phenols such as methanol, ethanol, propanol, butanol, benzyl alcohol, phenol and the like, these radicals being split off when the tin components are simultaneously introduced into the molecule. Of course, it is also possible to introduce the monofunctional alkoxy or oxyacid dikals into the molecule after the incorporation of the tin compound. Furthermore, the silicone compounds containing tin may contain the stannoxane grouping Sn-O-Sn, in which each tin atom is connected to 1 or 2 organic radicals as indicated above, by means of a direct carbon to tin bond. It is not necessary to use stoichiometric amounts of the tin part and the silicone part and smaller amounts of each in the molecule are covered by the invention. Furthermore, the tin-containing silicone compounds can also contain functional groups, such as e.g. hydroxyl groups, halogen groups such as chlorine, bromine and iodine, alkoxy groups such as e.g. methoxy, ethoxy, propoxy, butoxy and similar ester groups such as acyl groups and the like in the terminal position. Depending on the nature of the starting material, unbranched or branched silicone-containing compounds of relatively high or low molecular weight can be produced, and which can either be water-soluble or hydrophobic. Furthermore, the tin-containing silicone compounds can be mixed in any desired manner.

The tin-containing silicone compounds used according to the invention can be solid, amorphous, crystalline pastes or even liquid products, and can be incorporated into the reaction components in various ways. Thus, the liquid compounds are usually compatible with the hydroxyl polyesters and/or polyethers and can be added directly to these, while the water-soluble compounds can be introduced into the aqueous part of the reaction participants. Solid compounds can be dissolved in solvents such as acetone, aromatic hydrocarbons such as e.g. benzene, toluene, xylol and the like, chlorinated hydrocarbons such as ether and the like, esters such as dibutyl ether and the like, and any other suitable solvent. Furthermore, the reaction can be carried out in the presence of the solid compound by adding it in the form of a paste, e.g. to the organic compound, which contains at least two active hydrogen-containing groups.

The amount of catalyst will vary depending on the nature and composition of the reaction mixture. The amount of active tin in the silicone compound can also vary according to the compounds used. However, catalytic amounts are sufficient. Generally, preferred amounts are in the range of about 0.01 weight percent. to about 5% by weight, based on the total weight of the reaction mixture.

The cellular polyurethane plastic is produced by the simultaneous and good mixing of the components which include the organic compound containing

at least two active hydrogen-containing groups, organic polyisocyanate, water or others

propellants, as well as other additives, if desired. The mixing is preferably carried out in a mechanical mixer as indicated, e.g. in the U.S. Reissue Patent No. 24 514. I

in addition to the components already mentioned, it is possible to use other stabilizers, catalysts, dyes, fillers and the like. Suitable catalysts are e.g. N-Ethylmorpholine, N-Methylmorpholine, Triethylendiamine. dimethylbenzylamine, endoethylenepiperazine in small amounts, 1-alkoxy-3-dialkylaminopropanes such as 1-ethoxy-3-dimethylaminopropane and the like, permethylated N-ethylaminopiperazine1 and the like, as well as tin-containing compounds, such as e.g. dibutyl tin di-2-ethylhexoate, dibutyl tin dilaurate, stannous octate and others.

One can also use in connection with the catalyst stabilizers according to the invention, emulsifiers such as sulfonated castor oil and addition products of ethylene oxide with hydrophobic compounds containing one or more active hydrogen-containing groups, dyes, fillers, fire retardants, plasticizers and other stabilizers including silicone alkylene oxide copolymers, such as are described in German Patent No. 1,040,251 and silicone compounds containing basic nitrogen atoms and paraffin oils.

The cellular polyurethane plastic according to the invention is useful in many applications including both thermal and sound insulation, buffers and other padded articles, toys and the like.

In the following, the invention will be described with the help of examples.

Example 1.

100 parts by weight linear polypropylene glycol (OH number about 56), 39 parts by weight toluylene diisocyanate containing 2,4- and 2,6-isomers in a ratio of 80:20, about 1.5 parts by weight of a water-soluble siloxane-alkylene oxide polymer, 0 .7 parts by weight of a stannous siloxane prepared by transesterification of about 37.8 parts by weight of tetraethoxy-1,3-diphenyldisiloxane and about 140.4 parts by weight of dibutyltin-di-20

acetate (refractive index n D = 1.5142),

0.8 parts by weight of permethylated N-aminoethylpiperazine and 3.0 parts by weight of water are mechanically mixed in the apparatus, described in U.S. Pat. Reissue patent 24 514, whereby a foam material is formed which reaches its full height within about 2 min. and hardens after approximately 20 to 30 min. to form a product that has good strength and elasticity.

Example 2.

89 parts by weight of tetramethyl-1,3-diethoxy-disiloxane and 60 parts by weight of anhydrous polyethylene glycol (molecular weight approximately 300),

transesterified at 150° C/12 mm Hg and then at 130° C/12 mm Hg after addition of 70.2 parts (w/w) of ddbutyl tin diacetate and about 1 mole of acetyl chloride to give 156 parts by weight of a viscous stannous siloxane- polyethylene glycol copolymer which has

20

a refractive index n ^ = 1.4657.

100 parts by weight of a branched polypropylene glycol (OH number about 56) which is prepared by adding propylene oxide to a mixture of popane-1,2-diol and hexanetriol in a molar ratio of 1:1, 37 parts by weight of toluylene diisocyanate which

was used in example 1, 1.0 parts by weight of a water-soluble siloxane alkylene oxide polymer, 0.5 parts by weight of the previously described stannosiloxane-polyethylene glycol copolymer, 0.2 parts by weight of endoethylene piperazine and 2.8 parts by weight of water are mixed mechanically. A rapidly rising and settling foam material which has excellent mechanical properties is thereby obtained.

Example 3.

44.4 parts by weight of 1,3-diethoxytetramethyldisiloxane and 120 parts by weight of anhydrous polyethylene glycol having an average molecular weight of 300 are initially transesterified at 150° C./12 mm Hg until all ethanol is split off. 59 parts by weight of dibutyl dimethoxytin are then added and

the mixture is distilled at 150° C/12 mm Hg until all the methanol is removed. 184 parts by weight of a viscous oil having a refractive index n ^ are obtained as residue

1.4774.

100 parts by weight of a branched polypropylene glycol (OH number approximately 55) which is produced by adding propylene oxide to trimethylolpropane, 40 parts by weight of

the toluene diisocyanate used in the

example 1, 1.2 parts by weight of water-soluble siloxane-alkylene oxide copolymer, 0.4 parts by weight of the catalyst prepared as described above, 1.0 parts by weight of l-ethoxy-3-dimethylaminepropane and 3.1 parts by weight of water are mixed together. This results in a fast-rising and hardening foam that has good strength and elasticity.

Example 4.

100 parts by weight of a polyether (-OH number approximately 50) which has been prepared by the copolymerization of tetrahydrofuran, ethylene oxide, propylene oxide and epichlorohydrin, 42 parts by weight of an 80:20 mixture of 2,4- and 2,6-toluenediisocyanate, 1, 0 weight part of

a stannous siloxane having a refractive index of 20

index n D = 1.4426, and which has been prepared by transesterification at 130° C/12 mm Hg of 370 parts by weight of 1,17-diethoxymethyl-nonasiloxane and 351 parts of dibutyl tin diacetate with the addition of 2 ml of acetyl chloride (yield approx. 640 parts by weight), 1.2 parts by weight of a basic silicone oil of the formula

wherein n is an integer from 8 to 10, approximately 0.2 parts by weight of endoethylene piperazine and 3.3 parts by weight of water are mechanically mixed. A foam material is then obtained which has good mechanical and elastic properties and which rises and hardens quickly.

Example 5.

59 parts by weight of dibutyltin diacetate are added dropwise to 10 parts by weight of methyltriethoxysilane and 143.5 parts by weight of 1,19-diethoxymethyldecasiloxane while stirring and at 130° C. The acetic ester that is formed (29 parts by weight) is distilled off. 40.8 parts by weight of the yellowish oil thus obtained (refractive index n D = 1.4280)

is then transesterified with 50 parts by weight of an anhydrous polyethylene glycol propylene glycol monoalkyl ether (molecular weight about 1400) in 250 ml of anhydrous toluene and in the presence of 0.5 parts by weight of trifluoroacetic acid. as ethanol is split off. A high-viscosity oily stannosiloxane is obtained after distillation of all the volatile components at approximately 150° C/12 mm Hg.

About 100 parts by weight of the branched polypropylene glycol used in Example 3, 38 parts by weight of toluylene diisocyanate used in Example 1, 2.0 parts by weight of the oily stannosiloxane catalyst prepared as described above, 0.3 parts by weight of water-soluble siloxane-alkylene oxide copolymer , 0.7 parts by weight of 1-ethoxy-3-dimethylaminepropane and 2.6 parts by weight of water are mixed mechanically as described in example 1. A foam is obtained which rises and hardens quickly.

Example 6.

100 parts by weight of the polypropylene glycol used in Example 3, 38 parts by weight of the toluylene diisocyanate used in Example 1, about 2.6 parts by weight of water, 0.5 parts by weight of 1-methoxy-3-dimethylamino-propane, 1.5 parts by weight of a water-soluble lig siloxane-alkylene oxide copolymer and 1.0

parts by weight of a stannosiloxane prepared by transesterification of 44.5 parts by weight of 1.3 diethoxytetramethyldisiloxane and 70.2 parts by weight of dibutyl tin diacetate in the presence of 0.5 ml of acetyl chloride, and at a maximum temperature of approx. 130° C at 13 mm Hg under the exclusion of moisture, is mixed mechanically and produces a rapidly rising and hardening foam which has good physical properties.

Example 7.

35.1 parts by weight of dibutyl tin diacetate are first esterified at approx. 130° C/12 mm Hg with 102 parts by weight of a/o-diethoxy-polydimethylsiloxane having an average molecular weight of 475 with the addition of 0.5 ml of acetyl chloride. 105 parts by weight of a stannous siloxane which has a refractive index of 20 are obtained

index n D = 1.4292. 36 parts by weight of the stannous siloxane prepared in this way is transesterified at a maximum temperature of 17°C at 12 mm Hg with 51 parts of a polyether having an -OH number of 66, which has been prepared by adding 583 parts by weight of ethylene oxide and 650 parts by weight of propylene oxide to 1 mol of diethylene glycol monobutyl ether in the presence of alkali catalysts. 60 parts by weight of an alkylene oxide-stannosiloxane copolymer are obtained which have

20

a refractive index n D = 1.4612.

100 parts by weight of the polypropylene glycol used in Example 3, 38 parts (by weight) of the toluylene diisocyanate used in Example 1, 1.6 parts by weight of water, 0.5 parts by weight of 1-ethoxy-3-dimethylaminopropane, 2.0 parts by weight of dibutyltin dilaurate, 0, 5 parts by weight of the catalyst prepared as described above and 0.2 parts by weight of a 50% aqueous solution of a ricinolic acid sodium sulphonate mixed mechanically. A rather coarse-pored foam is obtained which has good strength properties.

Example 8.

100 parts by weight of the polypropylene glycol used in Example 3, 38 parts by weight of the toluylene diisocyanate used in Example 1, 2.6 parts by weight of water, 1.2 parts by weight of 1-ethoxy-3-dimethylaminopropane and 2.0 parts by weight of stannosiloxane having a refractive index of 20

index n D = 1.4055, and which is prepared by transesterification of 46.3 parts by weight of dioctyltin diacetate with 95 parts by weight of cx, -diethoxypolydimethylsiloxane (average molecular weight 475) in the presence of 0.5

ml of acetyl chloride at 170° C/12 mm Hg and hardens on standing for a relatively long time, mixes and forms a foam which rises and hardens quickly, but which has substantially closed pores.

Similar foams can be obtained by using approximately equimolar amounts of dibenzyl tin diacetate instead of dioctyl tin diacetate.

Example 9.

170 parts by weight of 1,19-diethoxymethyl-decasiloxane are added dropwise at 160° C and with stirring to 35 parts by weight of dibutyl tin diacetate and then approximately 24 ml of acetic acid methyl ester is distilled off which is formed in a molar ratio of 2:1. A clear yellowish liquid stannosiloxane is produced which has a refractive index n D 20

= 1.4161 and 4.7 percent OC2H, (calculated 4.9 percent).

36.2 parts by weight of this stannosiloxane is then reacted under reflux with stirring with 50 parts by weight of a polyalkylene glycol ether having a molecular weight of 1400. The reaction is carried out in 250 ml of toluene and in the presence of 1.0 parts by weight of trichloroacetic acid. The polyether-stannosiloxane obtained in this way is freed from volatile fractions and solvents by distillation at a maximum temperature of 150° C. at 12 mm Hg. The polyetherstannosiloxane is obtained in the form of a yellowish-brown viscous liquid and is used as catalyst and stabilizer in this example. The polyalkylene glycol ether used in this example was prepared by adding ethylene oxide and propylene oxide in a molar ratio of approx. 4:3 to n-butanol.

100 parts by weight polypropylene glycol used in example 2, 35 parts by weight toluylene diisocyanate used in example 1, 2.6 parts by weight water. 0.6 parts by weight of endoethylene piperazine and 1.5 parts by weight of the catalyst prepared as described above are mechanically mixed and give a highly elastic foam material having a volume density of 35 kg/m:'.

Example 10.

306 parts by weight of acetic anhydride are added with stirring to a mixture of 178 parts by weight of methyltriethoxysilane and 518 parts by weight of 1,13-diethoxymethylheptasiloxane. The mixture is kept at a temperature of approx. 130° C and the acetic acid ethyl ester which is formed in a molar ratio of approx. 1:3:3 is distilled off. A methylethoxypoly-

siloxane which has an OC2H5 content of approx. 7.2 percent corresponding to a molecular weight of :a. 1874. 37.3 parts by weight of 1,19-diethoxymethyl-decasiloxane are added to 80 parts by weight of methylethoxypolysiloxane and then 15 parts by weight of dibutyl tin diacetate are added dropwise at 170° C. After distilling off 9 m]. acetic acid ethyl ester, a yellow, thin liquid stannosiloxane is returned, which has a refractive index n D 1.4124. About.

4.3 per cent OC-Hr, (calculated approximately 4.6 per cent). 50 parts by weight of this reaction product is reacted in a manner analogous to that indicated in Example 9, with 68 parts by weight of the ethylene oxide-propylene oxide mixed polyether used in Example 1, to give a highly viscous condensation product which is used as a catalyst and stabilizer in this example.

100 parts by weight of the polypropylene glycol used in Example 2, 35 parts by weight of toluene diisocyanate used in Example 1, 2.6 parts by weight of water, 0.2 parts by weight of endoethylene piperazine, 0.2 parts by weight of dibutyltin dilaurate and 1.5 parts by weight of the catalyst prepared as indicated above is mechanically mixed in the apparatus described in U.S. reissue patent 24 514. A rapidly rising and hardening foam is obtained which has good mechanical properties.

Example 11.

35.1 parts by weight of dibutyl tin diacetate are added dropwise to a mixture of 62.4 parts by weight of the starting polysiloxane step according to example 10 and 84.8 parts by weight of 1,19-diethoxymethyldecasiloxane. The mixture is kept at a temperature of approximately 170° C during the addition of dibutyl tin diacetate and a quantity of acetic acid ethyl ester corresponding to an imolar ratio of 1:3:3 is distilled off. In addition to a somewhat gel-like substance, a thin liquid stannosiloxane containing 2.7% OC2H5 (calculated approximately 2.7%) is obtained.

48.5 parts by weight of this stannosiloxane is reacted in a manner analogous to that indicated in example 9 with 41 parts by weight of polyethylene glycol propylene glycol ether used in example 9 to give a high-viscosity condensation product which is used as catalyst and stabilizer in this example.

100 parts by weight polypropylene glycol used in example 2, 35 parts by weight toluylene diisocyanate used in example 1, 2.6 parts by weight water, 0.2 parts by weight endoethylene piperazine, 0.2 parts by weight dibutyltin dilaurate and

1.5 parts by weight of the catalyst produced as stated above gives a foam material which has similar properties to the foam material which was produced as described in example 10.

Example 12.

11.4 parts by weight of pentaethoxy-1,3,5-tri-phenyltrisiloxane are reacted with 70 parts by weight of 1,19-diethoxymethyl-decasiloxane and 28 parts by weight of dibutyltin diacetate at approx. 170-180° C, the acetic acid ethyl ester being distilled off to give a viscous stannous siloxane containing about 4.4 per cent OC2H5 (calculated about 4.7 per cent). 8.6 g of this reaction product is reacted in a manner analogous to that described in Example 9, with 16 parts by weight of the polyethylene glycol-propylene glycol ether described in Example 9 and in the presence of 1% trifluoroacetic acid to give a paste-like stannosiloxane alkylene oxide copolymer used as a catalyst and stabilizer in this example.

100 parts by weight of polypropylene glycols used in example 3, 35 parts by weight of the toluylene diisocyanate used in example 1, 2.6 parts by weight of water, 0.2 parts by weight of endoethylene piperazine, 0.2 parts by weight of dibutyl tin dilaurate and 1.5 parts by weight of the above-described stannous siloxane are mixed mechanically for to give a foam which rises in 1.5 min., has good elastic properties and which hardens completely after 20 min.

Example 13.

34.6 parts by weight of tetraethoxy-1,3-diphenyl-disiloxane and 50 parts by weight of 1,19-diethoxy-methyl-decasiloxane are reacted at 170-180° C with 20 parts by weight of dibutyltin diacetate, the acetic acid ethyl ester being distilled off. A further 50 parts by weight of 1,19-diethoxydimethyldecasiloxane and 5.8 parts by weight of acetic anhydride are then added. After complete removal of the acetic acid ester that is formed, a residue remains which consists of a clear yellow liquid having a refractive index n ^ =

1.4158. 42 parts by weight of this stannosiloxane is then reacted, as described in example 9, with 93.3 parts by weight of polyethylene glycol propylene glycol ether described in example 9, using sodium ethylate as catalyst, to form a yellow oil which is used as catalyst and stabilizer in this example .

100 parts by weight of the polypropylene glycol used in example 2, 35 parts by weight of toluylene diisocyanate used in example 1,

2.6 parts by weight of water, 0.2 parts by weight of dibutyl tin dilaurate and 1.5 parts by weight of the stannous siloxane prepared as described above, give a very elastic foam during foaming.

Example 14.

100 parts by weight of polyetherisocyanate obtained by reacting 100 parts by weight of linear polypropylene glycol (-OH number approximately 56) with 32 parts by weight of the toluylene diisocyanate used in example 1, 1.6 parts by weight of permethylated N-amino-ethyl-piperazine, 2, 0 parts by weight of water and 1.0 parts by weight of the stannous siloxane, which is prepared as described in example 13, gives a rapidly rising and hardening foam upon foaming.

Example 15.

100 parts (weight) of a polyester (-OH number about 60.2; acid number 1.3; viscosity about 17900 cP/25° C), which was obtained by esterification of adipic acid, trimethylol-propane and diethylene glycol, 35.5 parts by weight Toluylene diisocyanate containing 2,4- and 2,6-isomers in the ratio 65:35, 1.0 parts by weight of water, 1.0 parts by weight of dimethylbenzylamine, 1.0 parts by weight of a 50% aqueous solution of castor oil sulfate, 2.0 parts by weight of a 50 percent solution of a water-soluble benzyl hydroxydiphenyl polyethylene glycol ether and 1.0 part by weight of the stannous siloxane prepared as described in Example 10 are mechanically mixed in the apparatus described in U.S. Pat. reissue patent 24,514.

A foam is obtained which rises for about 1 minute, hardens after 10-15 minutes. and which has good elasticity and strength.

Claims (6)

1. Process for the production of isocyanate-based foams from polyhydroxy and/or carboxyl compounds, polyisocyanates and possibly water in the presence of tin compounds containing 4-valent tin, and in which each tin atom is bound via tin-carbon bonds to 1-3 organic radicals , characterized in that said tin compound is a silicon tin compound. 2. Method according to claim 1, characterized in that the silicone compound contains stannosiloxane groupings the molecule. 3. Method according to claims 1-2, characterized in that the silicone compounds contain the siloxane groupings -Si-O-Si- in the molecule. 4. Method according to claims 1-3, characterized in that the silicone compound contains the stannoxane groupings -Sn-0-Sn- in the molecule. 5. Method according to claims 1--4, characterized in that tertiary amines are used at the same time as additional catalyst sators, together with the silicone compound containing tetravalent tin. 6. Method according to claims 1-5, characterized in that water-soluble silicone oils or basic silicone oils are used as additional stabilizers.