DE1248929B - Process for the production of foams - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. Cl .:

C08g

German class: 39 b - 22/04

Number: 1 248 929

File number: F 42908IV c / 39 b

Filing date: May 16, 1964

Opened on August 31, 1967

A process for the production of foams from compounds with active hydrogen atoms, inert propellants, optionally with the addition of pore-regulating substances, found, which is characterized in that one derivatives of polyesters, polyethers, polyols or Polyamines or their mixtures of the general formula

R -

XC = O
YCH

10

R = polyester, polyether, polyol, polyamine residue, '5 X = O, NH, NR '

Y = H, OH,
Alkyl radical
with 1 to 20
Carbon atoms

with the proviso that Y and Z represent the hydrogen atom bonded to the vicinal carbon atom enable α-aminoalkylation,

Z = organic, electron-withdrawing residue,
η 2: 2, depending on the number of acylatable groups in R;

in the presence of low-boiling solvents as blowing agents with polyamines and an aldehyde or with low molecular weight condensation products of amine and aldehyde for implementation.

In the rest of the text, the compounds defined here with activated hydrogen will be of simplicity referred to as "CH-acidic compounds".

Process for the production of foams

Applicant:

Farbwerke Hoechst Aktiengesellschaft

formerly Master Lucius & Brüning, Frankfurt / M.

Named as inventor:

Dipl.-Chem. Dr. Alfred Kühlkamp, Hofheim;

Dipl.-Chem. Dr. Rudolf Nowack,

Frankfurt / M.-Schwanheim

The claimed process stands out from known processes for the production of foams from polyesters and the like in that stable amines are used instead of the very reactive isocyanates begins.

In the claimed method possibly arises from z. B. the formaldehyde and the Amine initially a methylolamine or, in the presence of alcohol, a methyloletheramine; with the CH-acidic Compounds are then set by the N-methylolamine or N-methyloletheramine to higher molecular weight condensates.

This reaction takes place according to the following scheme:

O = CX- R- X-C = O

Y-CH

z.

YCH
Z

+ 2CH0 + HN NH

R-X-C = O

I I

YC CH-N -

II ζ O = CX

I I

-N-CH C-Y

R -

X, Y and Z have the meaning given above: - X - R - X- = polyester, polyether, polyol or polyamine radical, the molecular weight preferably being between 40 and 4000.

In addition to this aminoalkylation, other reactions may also take place, e.g. B. between the carbonyl group of the CH-acidic compound and an amino group of the polyamine, between Aldehyde and 2 CH-acidic groups to the corresponding methyl-bis-compound or between aldehyde and two amino groups to the corresponding N, N-methylene-bis-compound. All of these reactions, which may also occur, contribute to the polymer linkage and crosslinking.

709 639/591

An example of a polymeric CH-acidic compound is the reaction product of an adipic acid-glycol polyester with terminal OH groups and diketene called. The compound corresponds to the formula

O = CO - R - OC = 0

I I

CH ₂ CH ₂

CH-acidic compounds are here, for. B. those that contain radicals in which one or more H atoms are activated at C by electron-withdrawing groups, such as. B. at

C = O

CH ₃

CH ₃

Here, R denotes a polyester residue composed of adipic acid and ethylene glycol with a molecular weight of around 400 to 4000.

In the present reaction, at least the simply stoichiometric amount of aldehyde is used used. When using z. B. primary amines and / or CH-acidic compounds with two active hydrogen atoms, the reaction can also continue and require a multiple of aldehyde.

The properties of the process products can therefore be varied to a large extent. With increasing Conversion of the aldehydes also increases the degree of crosslinking of the process product.

As polyester compounds come into question, the z. B. from polybasic acids, such as. B. adipic acid or phthalic acid, with polyhydric alcohols, e.g. B. ethylene glycol, butylene glycol, glycerin, hexanetriol or trimethylolpropane, can be prepared by known processes with a low acid number. as Polyethers come into consideration, for example, from ethylene oxide, propylene oxide or Tetrahydrofuran polymerized by itself or accessible as block copolymers by known processes are.

The polyols here are compounds such as ethylene glycol, propylene glycol, butanediol, glycerine, hexanetriol or higher molecular weight hydrocarbons bearing several OH groups.

Aliphatic, compounds containing aromatic or heterocyclic primary or secondary amino groups be used. For example, ethylenediamine, propylenediamine, butylenediamine, Piperazine, phenylenediamine or benzidine.

Primary or secondary amine components are suitable as the amine component for the above reaction with the aldehydes Di- or polyamines, ζ. B. ethylenediamine, 1,3-propylenediamine, 1,2-propylenediamine, 1,4-butylenediamine, 1,3-butylenediamine, ethylene glycol bis-y-aminopropyl ether, Piperazine, also piperazines substituted in the 2-, 3-, 5- and 6-positions, 1,6-hexamethylenediamine or diethylenetriamine. Instead of the free amines, their salts, such as acetates, can also be used.

Low-boiling solvents that are used in the invention Reaction serving as a blowing agent, are preferably liquefied halogen-substituted Alkanes, such as monofluorotrichloromethane, dibromodifluoromethane, l, l, 2-trichloro-l, 2,2-trifluoroethane, dichlorofluoromethane, Dichloro-tetrafluoroethane, trifluorobromoethane or mixtures of these substances. Leave it but also hydrocarbons, such as pentane or hexane, and ethers, such as diethyl ether, are used.

cn - CH ₂ - c:

O ₂ N

>, o

md -

CH ₂ - c;

NO ₂

<O

CH ₃ -C -CH-c:

, 0

R-CH

/ Ο -

It />

C CH ₂ C.

^x o -

; 0

O Cf

Il l ^x

C-CH ₂ -CH

, 0 -

*O

or

oO

HO - C - CH ₂ - CH

MD - -OH

Compounds which contain the acetoacetic acid residue are preferably suitable

CH ₃ -C-CH ₂ -C ^

^ O

wear. Among other things, they have the advantage of easy accessibility through implementation of

bonds that carry acylatable groups, ζ. Β. OH, NH, with diketene.

The above compounds can be obtained in a known manner.

To achieve uniform foams with a certain pore density, it is advantageous to use low Add amounts of a surfactant. There are z. B. polysiloxanes, block copolymers of polysiloxanes with polyethylene oxides, alkoxylated phenols, alkoxylated alcohols, alkoxylated Fatty acids, fatty alcohol sulfates, alkyl or aryl sulfonates and block condensation products Polyethylene oxide and polypropylene oxide.

In order to obtain a favorable ratio of foam formation to foam solidification, it is advantageous to if you do not have the CH-acidic compound with the propellant, the aldehyde and the amine in this Sequence or by reversing the sequence of the last two components mixed separately, but if you mix the mixture of acidic CH component and propellant with the separately prepared Combines condensate from amine component and aldehyde.

You can z. B. proceed so that one first reacts the aldehyde with a polyamine and then the low molecular weight condensation product thus obtained with the above-mentioned CH-acids Residual polyesters, polyethers, polyols or polyamines in the sense of an α-aminoalkylation can react in the presence of a low-boiling solvent. For the said aminoalkylation A suitable aldehyde is preferably formaldehyde, but other aldehydes are also possible, especially in Can be used in conjunction with formaldehyde. So you can z. B. acetaldehyde or crotonaldehyde together use with formaldehyde or alone.

example 1

A mixture of 80 parts by weight of adipic acid glycol polyester with the acid number <2 and a molecular weight of about 2000, 10 parts by weight of adipic acid glycol triol polyester with an OH number of 60 and an acid number <2 and the molecular weight of about 2000, 40 parts by weight of 1,4-butanediol, with the free OH groups of the compounds mentioned have been reacted with diketene to form the corresponding acetoacetic ester groups, is used with 40 parts by weight of monofluorotrichloromethane combined.

In this mixture is added 0.8 parts by weight of block copolymers of polysiloxane having polyethylene oxide for pore control, and 33 parts by weight of at - condensate produced 10 ⁰ C from 60 parts by weight of formaldehyde and 86 parts by weight of piperazine in 140 parts by weight of methanol using a high-speed added.

After a few minutes, an elastic foam with a density of 0.08 to 0.2 is obtained a few hours it will get its final strength.

Example 2

A condensation product is obtained from 180 parts by weight of formaldehyde and 258 parts by weight of piperazine in 380 parts by weight of methanol at temperatures below −10 ^{° C.} 29.5 parts by weight of this are mixed well with 20 parts by weight of butanediol bis-acetic acid ester and 15 parts by weight of monofluorotrichloromethane and placed in a foaming mold. The initially liquid mixture becomes viscous after 20 seconds and then foams up strongly. A very hard foam is obtained, the density of which in the dry state is 0.06.

Example 3

A mixture of 30 parts by weight of a slightly branched polyester made from adipic acid and ethylene glycol and pentaerythritol with an average molecular weight of 800, 20 parts by weight of butanediol- (l, 4) and 4 parts by weight of a polypropylene glycol having a molecular weight of 400, their respective free Hydroxyl groups are reacted with diketene, with 15 parts by weight of monofluorotrichloromethane and 0.2 parts by weight of a block condensation product made from polyethylene oxide and polypropylene oxide evenly mixed to regulate pores. 31.5 parts by weight of that in the example are carried into this mixture 2 described condensate of piperazine and formaldehyde.

The reaction mixture foams well within a short time and solidifies until the foam is completely formed. Temperatures of up to 45 ^° C. were measured inside the batch. The foam has a very good strength after a few hours, its density is 0.07.

Example 4

30 parts by weight of a slightly branched polyester according to Example 3 with a molecular weight of 800, 20 parts by weight Butanediol (1,4) and 4 parts by weight of a polypropylene glycol with a molecular weight of 400, their respective free hydroxyl groups are reacted with ketene, with stirring successively with 0.56 parts by weight a water-soluble polysiloxane to regulate the pores, furthermore 15 parts by weight of monofluorotrichloromethane and 6.9 parts by weight of formaldehyde in 6.9 parts by weight of methanol. Stir into the thick, clear and homogeneous mixture you quickly add 7.93 parts by weight of diethylenetriamine.

The reaction mixture foams up quickly and

after drying gives a solid foam with a density of 60 g / l.

Example 5

14.2 parts by weight of finely ground 1,6-hexamethylenediamine - bis - acetic acid amide are made with 17.5 parts by weight of a reaction product a branched polyester with an OH number of 560 and an approximate molecular weight of 400 with diketene and 6.5 parts by weight of piperazine stirred to a homogeneous slurry in which 0.8 parts by weight of one Polyalkylsiloxane as surface-active substance and 20 parts by weight of monofluorodichloromethane as propellant stirs in.

In this slightly yellow colored homogeneous mixture

12 parts by weight of 50% methanolic formaldehyde solution are stirred in on a high-speed stirrer. To Foaming begins a few seconds and ends after about 3 minutes.

A hard foam is obtained which, in the dry state, has a density of 70 g / l.

Claims (1)

Claim: Process for the production of foams from compounds with active hydrogen atoms, inert propellants, optionally with the addition of pore-regulating substances, thereby characterized in that one derivatives of polyesters, polyethers, polyols or polyamines or their mixtures of the general formula X = O, NH, NR 'Y = H, OH, Alkyl radical
with 1 to 20
Carbon atoms R - XC =
YCH IO R = polyester, polyether, polyol, polyamine radical, with the proviso that Y and Z enable the hydrogen atom bonded to the vicinal carbon atom for a-aminoalkylation, Z = organic, electron-withdrawing residue,
η S ^ 2, depending on the number of acylable groups in R; in the presence of low-boiling solvents as blowing agents with polyamines and a Aldehyde or with low molecular weight condensation products of amine and aldehyde for Implementation brings.