DE2854087A1 - SHEATHABLE LATEX BLEND - Google Patents

Description

2854037

P \. ie ιί? r - ;. · / -I te

MPD 227 Dr Be/sa

Albright & Wilson Limited, Oldbury, Varley, West Midlands

(Great Britain tannies)

Foamable latex mixture

90 9827/0722

description

The invention relates to the production of foams from rubber latex. These latices are aqueous dispersions of natural or synthetic rubbers and the foams are z. B. applied to the back of carpets to improve their appearance and to give the carpet weight and a more elaborate treatment »The latex dispersion is formulated with a chemical foaming agent (among other ingredients) to make a foam baaa ₉ which a large amount contained air evenly distributed through the latex »

So di © Selecting Yerschäumungsmittels ,, which is added to the latex is critical because this means _s must be able an optimally © Verschäumungskraft

to lend to a large LuftTOlumen enclose and create a foam that is stable and is not before curing to

A group of compounds, di © have been used as Yerschäumungsffiittel for Kautschullatiees _B are SuIfosuccinamate the general Formal

p O

CO " Ii *

-S-

09827/0722

In which R is an aliphatic group having 8 to 22 carbon atoms, one of the groups X or Y is a hydrogen atom and the other is a sulfate group SO ,, "* and M ^{+ is} a cation of an alkali metal, alkaline earth metal or ammonium.

The SuIfοsuccinamate are expedient by reaction of an amine RNH «with maleic anhydride and then with a sulfite, these reactions in the essentially proceed according to the following equations

-Τ ο η ο ρ? τ 7 rs 7 '*> --- ι

CONHR

RNH ₂ +

COOH

.CONH ₂ R

Il

so>

COOH

RNHCOC H COO +

H SO-

1 f

RNHCO — C C-

SO ₃ "H

> 00

9827/0722

The hydrophobic group R can be any aliphatic group having an average of 8 to 22 carbon atoms. The amines RNHp that have been used as starting material are synthetic or natural Sources derived. The vast majority of the surfactant sulfosuccinamates available to date contain groups R containing 10 to 18 carbon atoms contain, such as lauryl, myristyl, cetyl, stearyl, oleyl or cocoyl groups, the carbon atoms in the Group R are arranged in a straight chain.

These compounds perform useful as foaming agents for latices. They are sufficient good foaming agents to use in so-called non-gelling foaming systems, d. H. those in which the stability of the foamed latex is sufficiently good that the foam does not collapses before drying and curing can take place. In contrast to this are the so-called gel systems those in which the latex foam is relatively unstable and requires the addition of a gelling agent, to improve stability. However, these sulfosuccinamates used in non-gel systems suffer with the disadvantage that they are quite insoluble in aqueous media. As is the case with others surfactants is the case,. is desirable to reduce transport costs in the form of a concentrated solution to distribute which physical changes compared to itself with

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909827/0722

ι, a, ._

is stable over long periods of storage. The alkyl sulfosuccinamates, which are derived from natural amines, can only be prepared as solutions which contain 35 "to 40% by weight solids and even at these concentrations suffer from the tendency to excrete active substances as sediments or even when standing for long periods of time Careful selection of the length and distribution of the alkyl chain in the starting amine can make this problem less difficult, since generally shorter chains or alkenylamines result in sulfosuccinamates which have markedly improved solubility, but this improvement cannot be entirely Overcoming solubility difficulties, in particular the sedimentation during prolonged storage.The sulfosuccinamates, which are derived from starting materials which are synthetically produced amines, the amines containing alkyl groups with a branched carbon chain, show better solubility properties. In DE-AS 26 57 581 si nd sulfosuccinamates are described in which 50 % of the alkyl chains. have two methyl groups as branches.

It now became a special group of sulphosuccinates found which show improved solubility properties and are very useful as foaming agents for latices are. This group includes compounds of the general formula

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309827/0722

R 0R "h 0R" 1 '-NH C C CGO "

I ₁ U OR ₁ J -NH (j

ⁿ X

in which η is an integer with a value of 0 to 5, one of the groups X or Ύ represents a hydrogen atom, while the other is a sulfate group ^ R _{1 is} an alkylene group with 2 or 3 carbon atoms and R is an alkyl or alkaryl group with Represents 7 to 18 carbon atoms.

These sulfosuccinamates can be used as foaming agents in the production of latex foams from rubber latexes, which are preferably natural rubber latexes or latexes of non-carboxylated styrene-butadiene copolymers or mixtures of these two groups of substances. Rubber latices are usually traded as aqueous dispersions containing 50 to 65 or 70 wt -% contain solids.. These dispersions are formulated in a latex mixture which, in addition to the usual additives, contains the foaming agent.

Latex mixtures containing 1 to 10, preferably 3 to 8 parts by weight of sulfosuccinamate per 100 parts by weight of latex solids as defined above form an embodiment of the invention (the parts by weight data relate to sioh always on solid substance).

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909827/0722

Aa

The latex mixture is foamed with air, so that a foam is produced which has the desired density. This is expedient by continuous controlled introduction of the latex mixture and air into one continuously working mechanical foaming machine achieved.

The foam produced in this way is applied to the substrate, dried and cured.

In the usual production methods for carpets with latex coating on the underside, the foam is on applied to the underside of a continuous carpet tape, with the foam thickness regulated by a doctor blade will. The carpet is passed under a series of infrared heaters to allow itself to be passed through

a skin forms on the foam surface and then passed through a long oven to to harden and dry the foam at the same time. Substrates coated on the back with foam, which through Treatment with a foamable latex mixture according to the invention, and drying and curing of the foam form an embodiment of the invention.

The latex mixture usually also contains other ingredients such as a curing agent for the latex e.g. B. Sulfur and / or a sulfur-releasing compound,

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■ 909827/0721

such as zinc thiodicarbamate or zinc mercaptobenzothiazole, zinc oxides, and a filler ζ. Β »Calcium carbonate and an antioxidant. Optionally, a dispersant, e.g. B. a polyphosphate, and a thickener, z. B. a polyacrylate or methyl cellulose Need to be added to the latex mixture. The sulfosuccinate as a foaming agent can partially, z. B. up to 40 wt .-%, by a foaming agent, in particular an alkyl sulfate, an alkyl ether sulfate or amine oxide can be replaced.

The amounts of these ingredients that are used depend on the exact type of latex and the ones desired Properties of the particular foam.

The sulfosuccinamates preferred for the use according to the invention are those in whose formula η is one Has a value of 0-3, most preferably 0-1. Compounds that represent a mixture of individual compounds, in which η has different values, but the average value of η in the stated range falls also form part of the invention.

The group R ₁ can be an ethylene group -CHp-CHp, propylene group -CH ₂ -CH ₂ -CH ^ or isopropylene group -CH ₂ -CH-.

CH,

Most preferred sulfosuccinamates for use in accordance with the invention are those in which R _{1 is} a formula

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909827/0722

Is ethylene group, d. H. those compounds which are addressed as alkyl (polyethoxy) sulfosuccinamates can.

The alkyl chain R preferably contains 8 to 18, e.g. B. 8 to 14 and most preferably 11 to 14 carbon atoms. The carbon atoms can be straight-chain or in In the form of branched chains or they can be arranged as a mixture of individual compounds with branched There are chains and straight chains.

The sulfosuccinamates can be prepared in the acid form or in the form of a salt of this acid. Appropriate they are usually made in the form of their sodium salts.

Those compounds in which R is a branched alkyl group is, are new connections. Accordingly, in a further embodiment, the invention includes novel compounds the general formula

H H

NH C C COO

X Y

in which η is an even number with a value from 0 to 5, R _{1 is} an alkyl group which has two or three carbon atoms, one of the groups X or Y is a hydrogen atom and the other is a sulfate group S0, ~ and

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7/0722 ORIGINAL INSPECTED

54087

R is an alkyl or alkaryl group of 7 to 18 carbon atoms in which the aliphatic carbon chain is branched at at least one point.

This SuIf οsuccinamate and the other SuIfοsuccinamate can be derived from primary alkyl alkoxy amines using the usual techniques of synthetic organic chemistry, in particular the method of preparation mentioned above.

The amines, which are used as starting material in the production of the alkyl-alkoxy-sulf οsuccinamate, can in turn be derived from alcohols of the formula ROH, natural or synthetic Products can be. These can be as desired: amines., E.g. U.S. Patents 2,371,892 and 2,372,624 Reaction with acrylonitrile and subsequent hydrogenation can be converted according to the following equations:

ROH + CH ₂ =. CH-CN

₂
ROCH ₂ CH ₂ CN - ^ RO

Alternatively, the alcohol can be condensed with an alkylene oxide and the compound obtained can be ammonolyzed

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909827/0722

according to the following equations (for ethylene oxide):

ROH + χ (CH ₂ CH ₂ O) => R (OCI ^ CH ^ OH

NH ₃

₃ R (OCH ₂ CH ₂ ) OH ^ R (OCH ₂ CH ₂ >

These alkyl alkoxyamines can then be reacted with maleic anhydride using conventional methods, e.g. B. by adding a practically equimolar amount of the amine to molten maleic anhydride at temperatures of 60 Ms 110 ^° C., which are maintained for 1/2 to 1 1/2 hours. The maleamide formed as an intermediate product can be added to an aqueous solution of the sulfite of an alkali metal, alkaline earth metal or of ammonium sulfite or of sulfurous acid and the reaction mixture can be kept at a temperature of 40 to 100 ^° C. for 1 to 5 hours. Even after a prolonged reaction time, the prepared solution of sulphosuccinamate, regardless of whether it is in acid form or in the form of the salt, will be contaminated by unreacted amine. The product is therefore preferably produced in the form of the alkali metal salt, in particular the sodium salt.

These solutions of the sodium salts of the sulfosuccinamates, the can be used according to the invention can be formulated in mixtures containing up to 45% by weight of solid material

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keep. Preferably they are made and sold in the form of solutions that contain 35Ms 45 wt% solids contain.

The invention is illustrated in more detail by the following examples. Examples 1 to 4 illustrate the Preparation of sulfosuccinamates useful in the present invention.

example 1

There were 265 g (1 mole) of a synthetic primary amine of the formula ROCHpCH adopted added ₂ NHp with stirring to 98 g (1 mol) of maleic anhydride at temperatures between 80 and 90 ⁰ C. The amine used was a commercially available substance in which R is a mixture of alkyl groups with 11 to 15 carbon atoms, about half of which are straight-chain and the other half are branched. The maleamide was stirred at this temperature for an additional 30 minutes. The molten maleamide obtained as a product

^ö was slowly added to a stirred solution of 130 gf water

(1.03 mol) of anhydrous sodium sulfite in 700 g / at one

Temperature of 50 to 75 ° C added. The solution obtained was kept at a temperature of 70 to 75 ^° C. with stirring for a further 3 hours. The clear solution obtained contained 40 % solid material of a disodium alkyl

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Sulfosuccinamate with a viscosity of 44.9 cSt at 20 ^° C. remained a clear solution even after storage for 60 months at ^{0 ° C.} In contrast, under the same storage conditions, a solution of disodium alkylsulfosuccinam ± 35% solids made from a synthetic primary amine RNHp., Where R is an aliphatic group having 13 to 15 carbon atoms - and about 50 % of the groups contained branches , a small amount of insoluble matter.

At concentrations above 45% solids content of this alkyl alkoxy sulfοsuccinamat formed a gel at 20 ⁰ C.

Example 2

There were 136 g (0.5 mole) of a synthetic primary amine of the general formula RO CHpCHpCHpNHp with stirring to 539 g (0.5 mol) of maleic anhydride at a temperature of 60 to 70 ⁰ C. The maleamide obtained as the reaction product was stirred at this temperature for a further hour.

The alkyl-alkoxy-amine used as the starting material was a commercially available product which, as group R, is a mixture of alkyl groups with 12 and 14 carbon atoms.

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7/0722

54087

held. The carbon atoms in group R were straight chain.

The molten maleamide reaction product was added slowly with stirring to a solution of 69.3 g of sodium sulfite and 3.2 g of sodium hydroxide in 644 g water at a temperature of 65 to 70 ⁰ C. The reactant solution was held at this temperature for about 30 minutes.

The resulting clear solution, which contained 35 % disodium alkylalkoxysulfoeuccinamate, remained clear when stored at 20 ° C., but tended to ^{excrete a very small amount of insoluble substance when stored at 0} ° C.

The viscosity of this 35% solution at 2O ⁰ C was 60.0 cSt.

In contrast, a 35% solution of disodium aifryl sulfosuccinamate made from a synthetic primary amine RHNp, where R was an aliphatic group of 15 to 17 carbon atoms and about 50 % of those groups contained branched chains, precipitated a significant one Amount of insoluble substance when stored at O ⁰ C for the same period of time.

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909827/0 72 2

ORIGINAL

Example 3

136 g (0.5 mol) of a synthetic primary amine of the formula ROCH ₂ CH ₂ CH ₂ NH _{2 were added} with stirring to 53.9 g ₍ 5 mol) of maleic anhydride at a temperature of 60 to 70 ^° C. The Maleamide reaction product ■ was stirred at this temperature for a further hour.

The alkyl-alkoxy-amine used for the preparation was a commercially available distilled product, where R is a mixture of 12 and 14 carbon atoms in the alkyl chain was. The carbon atoms in group R were arranged in a straight chain.

The molten maleamide reaction product was added slowly with stirring to a solution of 693 g sodium sulfite and 32 g of sodium hydroxide in 644 g water at a temperature of 65 to 70 ⁰ C. The reactant solution was held at this temperature for about 30 minutes.

The resulting clear solution contained 35% solids of disodium alkyl-alkoxy-sulfosuccinamate, as in the product of Example 2, and remained clear on storage at 20 ⁰ C, but tended to leaving a small amount of insoluble substance during storage at 0 ⁰ C .

The viscosity of this 35% solution at 20 ° C was 15.9 cSt.

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2 7/0722

Example 4

According to Example 2 using the same molar ratios and reaction conditions, a solution of sodium alkyl alkoxy sulfοsuccinamate with 40 % solids was prepared from a commercially available alkyl alkoxyamine ROCHpCHNEL with an alkyl group R composed of highly branched alkyl chains with 7 to 9 carbon atoms.

The viscosity of these 40 #igen solution at 20 ⁰ C was 116 cSt. This solution remained clear on standing at 0 and 20 ⁰ C. Solutions of AlkylTalkoxy-sulfosuccinamate remained clear liquids at 20 ⁰ C at concentrations up to 45.9%. Above this concentration, these solutions tended to gel.

Example 5

Using the molar ratios and reaction conditions of Example 2, a clear 35 % solids solution of a sodium alkyl alkoxy sulfosuccinamate from an alkyl alkoxy amine was commercially available with _{ROCH 2} CH ₂ CH ₂ NH ₂

Alkyl groups R from highly branched alkyl chains with 9 to 13 carbon atoms are produced.

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909827/0722

The viscosity of this clear solution was 25 cSt at 20 ^° C.

When long standing at 0 ° and 20 ⁰ C this solution remained clear.

Example 6

The effectiveness of various sulfosuccinamates has been made by making a number of latex mixtures according to the following formulation:

Parts by weight .per 100 parts by weight of latex solids * Intex 131 100 Hardener dispersion 8th Foaming agent 5 filler (Calmonte AD) 150 Calgon PT 1

* Intex 131 = synthetic non-carbonxylated styrene-butadiene copolymer latex International Synthetic Rubber Company Limited.

The weight is based on dry matter.

Each latex mixture was foamed by whipping in air with a household blender for 10 minutes and the Density was recorded. Two samples of the wet foam were spread on metal plates to the same thickness. One sample (A) was immediately placed in an oven for 30 minutes

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9 0 9 8 2 7/0 722

Hardened at 130 to 140 ° C. The second sample (B) was made Allowed to stand for 10 minutes and then cured in a similar manner. The second sample therefore showed the storage stability of the wet foam. The cured foams A and B were visually checked for evenness of bubble structure on the surface, uniformity of the bubble structure in the specimen and the cracking of the surface checked. Grades ranging from 1 to 5 were given for each grade, with the higher grades being better Behavior represented. The results are in the following Table compiled.

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909827/0722

Example no.

Amine starting material for the sulfosuccinamate

-Vh-

Evaluation of sample A.

Evaluation of sample B overall

Surface surface mass surface structure bubble cracks

Surface surface mass surface structure
bubble cracks

SO

CJTi

Minimal

Foam density

(g / cm ⁵ )

CD
CO5

is)
to

Hoe 2504/2 5 3 4 5 3 4 24 0.22

Kemamine AP860 5 4 5 5 2 4 25 0.20

Kemamine AP860D 5 4 5 5 2 5 26 0.21

Hoe F1040D 5 5 2 4 3 2 21 0.21

Kemamine AP99O 5 3 3 5 2 2 20 0.22

Synprolam 35 5 5 5 3 4 4 26 0.19

B tallowamine 5 4 5 5 3 3,; 2Y? 0.21

(natural origin)

Tallowamine 5 5 5 45 5 29 0.23

(natural origin)

D Primene 81E- 3 5 0 2 3 013 0.29

strongly branched aliphatic group R with 12-14 G atoms

A comparison of the values given for B and C shows that foams made according to this technique May be subject to experimental errors. The evaluation for D shows a bad behavior that is technically

is no longer acceptable.

Claims (16)

Claims 1. Foamable latex mixture consisting of an aqueous one ..- ■ dispersion of a natural or synthetic rubber latex and possibly. a foaming agent in addition to hardeners, dispersants, antioxidants, fillers and others usual ingredients, characterized in that it is a sulfosuccinamate of the general foaming agent formula H H \ I ROR. (OfL) NH C C COO " 1 1 η j, X Y contains, in which R is an alkyl or alkaryl group with 7 to 18 carbon atoms, R ^ an alkylene group with 2 to 3 carbon atoms, η an integer with a value from 0 to 5 and one of the groups X or Y, respectively Means hydrogen atom while the other means one Sulfate group i st. 2. Latex mixture according to claim 1, characterized in that the latex is a natural rubber latex, made of a latex a non-carboxylated styrene-butadiene copolymer or a mixture of these latices. 3. latex mixture according to claim 1 or 2, characterized in that the latex used in an amount of 50-70% by weight, based on solids, is present. 909827/0722 - 3 - ORIGINAL INSPECTED -X- 4. latex mixture to the preceding claims, characterized in that it contains 1 to 10 parts solids _f per 100 parts of rubber solids in the latex containing the SuIfosuccinamats. 5. Latex mixture according to claim 4, characterized in that it contains 3 to 8 parts of sulfosuccinamate per 100 parts by weight of rubber solids in the latex. 6. latex mixture according to the preceding claims, characterized in that the sulfosuccinamate is a Is a compound in whose formula η has the value 0 to 3. 7. latex mixture according to the preceding claims, characterized in that in the formula R ^ is an ethylene group is. 8. latex mixture according to the preceding claims, characterized in that in the formula R is an alkyl group is of 8 to 18 carbon atoms. 9. latex mixture according to the preceding claims, characterized in that it also contains a curing agent. 10. Use of a latex mixture according to claims 1 to 909827/0722 ORlGlNAt INSPECTED for the production of foamed, dried and hardened latex coated substrates. 11. Sulphosuccinamate of the general formula (OR ₁ ) _n NHCO CQ COO " t 1 χ γ in which R, R ₁ , n, X and Y have the meaning given in claim 1. 12. sulfosuccinamate according to claim 11, characterized in that in the formula R is a branched-chain alkyl group having 8 to 14 carbon atoms. 13. sulfosuccinamate according to claim 12, characterized in, that in the formula R is a branched chain alkyl group having 11 to 14 carbon atoms. 14. sulfosuccinamate according to claims 11 to 13, characterized in that η in the formula has a value of Has 0 to 3. 15. sulfosuccinamate according to claim 15, characterized in that that η has a value of 0 and 1 in the formula. 16. sulfosuccinamate according to claims 11 to 15, characterized in that in the formula R _{1 is} an ethylene group. 909827/0722