DE2407742B2 - METHOD OF FIRE-PROTECTING CELLULOSE-CONTAINING FIBER MATERIALS USING PHOSPHONO-PROPIONAMIDE DERIVATIVES - Google Patents

Description

R ₁ O

OR ₃

/ I!

R ₂ OO

PCH ₂ CH ₂ CNHCH ₂ OCH ₂ NHCCH ₂ Ch ₂ P

in which R ₁ to R _{4 are} identical or different alkyl, alkenyl or alkoxialkyl groups with not more than 10 carbon atoms, impregnated, then dried at a temperature in the range from room temperature to 200 ° C and finally at a temperature of 120 to 200'C over a period of 30 seconds to

■ | i \

O OR ₄

Is cured for 10 minutes.

2. The method according to claim 1, characterized in that a phosphorus compound of the general formula (I) is used in which R ₁ to R _{4 are} each Afkyi- or haloalkyl groups with not more than 4 carbon atoms.

The present invention relates to a method for making cellulosic fiber materials fire-proof using phosphono-propionamide derivatives.

LJm cellulosic fibrous materials are fireproof to make, the urea-phosphate method has conventionally been used / B. in Japanese Patent Publication 4950/1962. That way however, treated fabric has many disadvantages such as: B. low resistance to washing, rough Surface or finish and both extremely poor grip and severely reduced strength.

As a relatively new method, the method described in Japanese Patent Publication 691 726 is

R ₁ O

driving became known. So z. B. described in this patent that the N-methylolated Phosphorus compounds with a methylene ether bond formed by condensation in the presence of an organic Solvent such as B. toluene or benzene of 3 - dimethylphosphonopropionic acid - methylolamide followed by methylolation with a reagent capable of generating formaldehyde are suitable for making cellulosic fibrous materials fire-proof. In lines 17-19 of column 21 of the published Description of this patent, however, it is clearly shown that the intermediate compounds do not require methylolation experienced, these are the compounds represented by the following general formula (I)

OR ₃

PCH ₂ CH ₂ CNHCH ₂ OCh ₂ NHCCH ₂ CH ₂ P R ₂ O OO OO OR ₄

are reproduced, in which R ₁ to R _{4 represent the} same or different alkyl, alkenyl or alkoxyalkyl groups, do not have a permanent flame-retardant effect on cotton fibers.

On the other hand, the N-methylolated phosphorus compounds with a methylene ether bond smell, those in the method described in Japanese Patent Publication No. 691,726 cited above are used even after formaldehyde and also tend to form easily Formaldehyde in the course of the flame test equipment of cellulosic fibrous materials, whereby there arises a disadvantage that the work area or the environment is extremely deteriorated.

From the German Offenlegungsschrift 2127313 oo flame retardants are now known, those of 3- (dialkyl - phosphono) - propionic acid - N - methylolamides or 3 - (dialkyl - phosphono) - propionic acid camides. The phosphorus-containing product for fire protection of cellulosic! Fasermalerial ds becomes by self-condensation from the N-Me-Ihylolamid echo. However, the conversion products are a mixture of self-condensation products, the composition of which cannot be defined in more detail. Furthermore, the known phosphorus-containing condensation product is in the form of a Layer applied to the material to be treated and covers this with a resin film. Through this If the surface of the treated materials becomes rougher, the entire material loses its softness Handle, and the adhesive applied protective layer requires care when washing, because the resistant wedge of the treated cellulosic material is reduced compared to washing.

In contrast, it is the object of the present invention to provide a method for making fire-proof cellulosic materials using phosphono-propionamide derivatives which despite the flame-retardant effect, the cellulose-containing material is left soft and grippy and the washing resistance of the cellulosic material is not reduced. Furthermore should no annoying alchemy vapors occur during the process.

This object is achieved by a method of the type mentioned at the beginning, which is characterized by

is drawn that the cellulose-containing material in a treatment bath with a 5 to 80% solution of a Phosphorus compound of the general formula (I)

R ₁ O

OR ₃

PCH ₁ CK CNHCH ₁ OCH ₁ NHCCH ₂ Ch ₂ P ^

/ Il "Ί"^"Il: \

R ₂ O OO OO OR ₄

in which R ₁ to R _{4 are} identical or different alkyl. Alkenyl or alkoxyalkyl groups with not more than 10 carbon atoms are impregnated, then dried at a temperature in the range from room temperature to 200 ° C. and finally cured at a temperature of 120 to 200 ° C. for a period of 30 seconds to 10 minutes.

In a preferred embodiment of the process according to the invention, a phosphorus compound of the general formula (I) is used in which R ₁ to R _{4 are} each alkyl or haloalkyl groups which have no more than 4 carbon atoms. In particular, all of the radicals R ₁ to R _{4 can be} methyl groups, isopropyl groups or chloroethyl groups.

The phosphorus compound of the general formula (I) is produced by condensation of a phosphono-propionamide with paraformaldehyde in the presence of an acid catalyst.

The phosphorus compound used in the method of the present invention is different from the polymeric reaction product known from the German Offenlegungsschrift 21 27 313 in that that instead of a methylene bond it has a methylene ether bond and therefore also in hers Effect is different from the known compound. While the well-known phosphorus compound theirs When the cellulose-containing material is treated as a layer, the inventive reacts Connection by breaking the methylene ether bond with the OH groups of the cellulose, without forming a resin film on the surface of the material to be treated. That like that treated fibrous cellulosic material is therefore still extraordinary even after the treatment soft and easy to grip and has excellent resistance to washing.

Since the compound (I) used according to the invention is a uniform substance.

R ₁ O

ίο which also in the reaction with the OH groups of the Cellulose material does not split off formaldehyde, there is the further advantage that when working there is no nuisance caused by aldehyde development.

When cellulosic fibrous materials are treated by the method of the invention for Fire-proofing are subjected, the phosphorus compounds nn; a multi-ether bond however, can be used without N-methylol groups, as indicated by the general above Formula (I) are given, these materials are given fire resistance without affecting them lose their resistance to washing or their good grip.

Furthermore, it is by the method of the invention possible to safeguard the working environment in the treatment of cellulosic fibrous Materials to improve extremely. In addition, the included in the method according to the invention

jo put phosphorus compounds (I) easy to manufacture. The drawing shows an infrared absorption spectrum a compound (I) used according to the invention with a methylene ether linkage, but without Methylol groups, namely of the N.N "-Ox \ mcth \ - lenbis (dimethylphosphonopropion) amide.

The process for the preparation of the phosphorus compounds (I) necessary for the process of the invention is in no way limited to any particular procedure, and it may be a variety aer-like procedures can be used.

The following three methods are mainly preferred:

The first method comprises the condensation reaction with dehydration in the presence of a

Acid catalyst, such as. B. p-foluenesulfonic acid c. of the monomethylol derivative of a 3-dialkylphosphonopropionamide, as is also described in Japanese patent specification 6 46 127. according to the following equation (1 ):

-H ₂ O 2 PCH ₂ CH ₂ CNHCh ₂ OH

(D

R, O O

In this way, however, the phosphorus compounds (I) are difficult to obtain with a relatively high purity and a formaldehyde odor tends to remain in the product.

The second more preferred method involves the condensation of N.N'-oxymethylene bisacrylamide with a diester of phosphorous acid either in the presence of a solvent such as z. B. dioxane. or without solvent in the presence of melhylai. as indicated in the following equation (2) a Hasischen catalyst, such as. B. Give sodium is:

CH ₂ CHCNHCH ₂
O

R, O

R, O

POIl

In this preparation of the phosphorus compounds III, however, is the process for making N.N'-Oxidimcthylenbisiicryhiniid, which is used as a starting material is used, relatively complicated, and in addition, the impurities that are present in contains the N, N -oxidimethylene bisaaylamide, notable adverse effects on the catalyst for those given in equation (2) above Reaction off. thus eliminating the need for cleaning arises, as / .. B. by recrystallization. As a consequence of this, the thus obtained Phosphorus compounds (I) are relatively expensive.

The third most preferred method involves the condensation reaction of a phosphonopropionamide in the presence of an acid alkaline analyzer with formaldehyde, directly forming the phosphorus compound (I) is generated as in the following Equation (3) is given:

R ₁ O

2 V (H ₂ CH ₂ CNH ₂ + 2CH ₂ O ^ ^ (I) ₄ || u

/ Il Il

R ₇ OOO

It is widely known to the person skilled in the art that phonopropionamide in the condensation reaction the methylene bisamide compound is formed when 20 is converted into the methylene compound (II) with formaldehyde

an acid amide is condensed with formaldehyde under acidic conditions. So the phosum is also converted, as given by the following equation (4) :

R ₁ O

PCH ₂ CH ₂ CNH ₂ 4 CH ₂ O

/ Il Il

R ₂ OO

R ₁ O

OR ₁

PCH ₂ CH ₂ CNHCh ₂ HNCCH ₂ CH ₂ P

/ Il Il Il Il \

R ₂ O OO OO OR ₂

(II) + H ₂ O

The formation of the methylene compound in accordance with the reaction given in equation (4). however, only takes place when the pH of the reaction system is strongly acidic, ie not higher than 0.5. If the pH of the reaction system is in the range of 0.5 to 5, it does not occur and the phosphorus compound (I) is formed as shown in equation (3). Thus, if the condensation reaction of a phosphonopropionamide with formaldehyde is carried out under acidic conditions, it is possible to produce only the phosphorus compound (I) with methylene ether linkage without forming the methylene compound (II) by precisely adjusting the pH in the reaction system.

The optimum pH in the reaction system for producing the phosphorus compounds (I) will vary to some extent with the reaction temperature, although it is generally in the range of 0.5 to 5, and preferably in the range of 2 to 4. The use of a pH value outside this range is not possible, since if the pH value of the reaction system in the strongly acidic environment vnn njch! is higher than 0.5 , the methylene compounds (II) are formed, and since when the pH of the reaction system is not lower than 5, a higher temperature and a longer reaction time are required, thereby causing side reactions such as. B. the Cannizzaro reaction of formaldehyde, the hydrolytic reaction of the amide group and the hydrolytic reaction v "> n phosphoric acid ester.

As the acidic substances for adjusting the pH value in the reaction system to 0.5 to 5, there can be used inorganic ones Acids such as B. hydrochloric acid, sulfuric acid and phosphoric acid, organic acids such as

z. B. p-Toluenesulfonic acid and strongly acidic ion exchange resin c be used.

The reaction temperature should be selected in accordance with the pH of the reaction system, although it is generally in the range of 30 to 140 ° C and higher, preferably in the range of 50 to 90 ° C.

Any desired compound can be used as the source of formaldehyde in this process, who is able to. Formaldehyde under acidic conditions submissions, z. B. polyoxymethylene dialkyl ether, Trioxane, tetraoxane, paraformaldehyde or an aqueous formaldehyde solution. Particularly suitable sources of formaldehyde are paraformaldehyde with an aldehyde concentration of not more than 80% by weight, and aqueous formaldehyde solutions, since they make the reaction according to equation (3) particularly easy is to be carried out.

The reaction given in equation (3) is an equilibrium reaction. It is therefore to achieve complete conversion of the starting materials into the phosphorus compounds (I) is required, both the water produced as a by-product and the water contained in the formaldehyde source

the reaction sintering to purify / to remove of water from the reaction it is sufficient. the water under normal pressure alvudeslilliereii. Around Suppress side reactions / u or prevent the evaporation of the 1 oimaldchvdquclle isi however, it is advantageous to keep the water under reduced Pressure off / distill or azeotropically remove it. As solvents for use in azeolropic distillation, such solvents are conventionally used used, which separate after cooling from the liquid phase, z. B. benzene. Toluene. Cyelohexane;> the carbon tetrachloride.

The methylene ether linkage in the various methods obtained by the various methods enumerated above Phosphorus compounds (I) can be easily quantified, e.g. B. by infrared absorption spectroscopy or by chemical analysis, in which the formaldehyde content after decomposition in a dilute aqueous acid solution is determined quantitatively.

In the phosphorus compounds (1) used in the process according to the invention, R ₁ to R _{4 are} identical or different alkyls. Alkenyl or alkoxyalkyl groups, each group not exceeding 10 carbon atoms. preferably no more than 4 carbon atoms. Of these groups, the alkyl and haloalkyl groups are preferred, and R ₁ to R ₄ are each preferably methyl. Isopropyl or chloroethyl groups.

To accelerate the staltfindenden in which erlindungsgemäßen VCrHiI-on reaction of the cellulosic materials Wed ¹ to Phosphoi \ erbinilmiL'cn (Il comb milks catalysts -n how sr "hciktimmlichcrwei.se for Hard of Aminoaldclndha'ven be used for. B. Ammonium chloride, rihophosphoric acid, magnesium chloride, / mkiiitra! ■ · / mkborofluoride.

I> u Kim-, lUi.uitin iler phosphorus compound (1) in '.- ■ ii! ".' Iichandluni used in the crfinuiingsp-rnn procedure." - ba <l can with the desired degree of FlamnienbeMändii-'kcit. to be awarded, vanieren. However, you today in the range of 5 to ^ H (It-W ⁰ O, and preferably in the range of 20 Hiv. 50 wt ¹ V

In order to impregnate a cellulosic paint with the treatment solution described above, a variety of known methods can be used, such as ζ. Β Pressing between rollers. Spray or centrifuge. The type of drying is arbitrary, and in practice drying at any temperature between room temperature and 200 (is sufficient Perform C satisfactorily for periods of 30 seconds to 10 minutes.

In the process according to the invention, aminoaldehyde resins can also be used together with the phosphorus compounds (I) can be used. As such aminoaldehyde resins, the reaction products come from one Variety of low molecular weight amino compounds commonly used as starting materials for the Manufacture of aminoaldehyde resins can be used in question, e.g. B. the reaction products of urea. Melamine, thiourea, ethylene urea, guanidine or urone, with formaldehyde as well the alkoxylated derivatives of these reaction products

When such aminoaldehyde resins are used together with the phosphorus compounds (I) working environments are extremely deteriorated due to the generation of formaldehyde. Whom the phosphorus compounds (1) according to the method of the invention are used alone, germination occurs Generation of formaldehyde, and therefore the working environment is not deteriorated in any way tert. In view of this, too, the sole use of the phosphorus compounds (I) is much advantageous more liable.

Specific embodiments of the invention will now be explained in more detail by means of examples.

Example I.

A solution of! 84 g (1 mol) of N.N'-oxime-methylene bis-acrylamide and 242 g (2.2 mol) of dimethylphosphine in 300 cm ^{1 of} dioxane is heated to 40 ° C. and a methanolic sodium methylate solution (8 g of sodium K) og methanol) added as a catalyst in portions with stirring. After adding sth; ² , the volume of the sodium methylal solution, an exothermic reaction takes place and the reaction temperature rises. Thereafter, the catalyst is added in portions in such a way that the reaction temperature is kept at 80 ° C. After the addition of the catalyst has ended, stirring is continued at the same temperature for about 1 hour to complete the reactor. The reaction mixture is distilled under reduced pressure to remove dioxane and excess dimethyl phosphite, whereupon 407 g of N.N'-oximethylene bis (dimethylphosphono propionlamide (general formula (I): R, to R, = CHj]) as a clear viscous Liquid holder.

No free formaldehyde is found in this product, but it does contain bound formaldehyde hyd. namely 0.08% in the form of methylol groups and 14.71% in the form of methylene ether groups. From this it can be seen that the product is 99.1% pure.

The infrared spectrum for this product is shown in FIG.

A cotton body is then treated in an aqueous treatment bath containing 30% N, N'-oxymethylene bis (dimethylphos phonopropion) amide and 0.4% ammonium chloride, prepared according to the above procedure, dried at 90 ° C. and cured at 150 ° C. for 4 minutes . In the flame resistance test carried out after the washer, the treated fabric shows incombustibility.

L ^! To compare the method of the present invention with the method known from German Offenlegungsschrift 212731: the following test is carried out.

3- (Dimethvlphosphono) -propionic acid-N-methylol · amide is given in accordance with that in the German Offenlegungsschrift 2127 313 Manufacturing process II produced.

In a stirred flask of 500 volume parts which with water separator and thermometer is provided, 264 parts of an 80% aqueous solution of 3- (dimethylphosphono) propionic acid-N-methylolamide. 1 part p-toluene sulfonic acid

Brought monohydrate and 200 parts of benzene to the boil with rapid stirring. 59.8 parts of water are deposited azeotropically within about 3 1/2 hours. The benzene is then brought to completion by toluene and self-condensation at the boiling point of toluene in 48 hours. It will thus contain a total of 69 parts of water, which after deduction of the water contained in the starting product gives 16.2 parts of water, which is formed during the condensation. The toluene is then largely removed, and filtered the Reaklionsprodukt in 80 parts of methanol and then the methanol and residual amount of toluene distilled off in vacuo at about 50 C. 165 parts of an opaque syrupy product are obtained which still contains 1.8 parts of total formamide. Of this, 0.95 parts are available as free formaldehyde and 0.02 parts as formaldehyde in methylene ether form

A cotton body is then placed in a treatment bath treated, which is a 30% aqueous solution of the polycondensation product obtained above contains. Dani is subjected to the test for flame resistance. In the test a considerable amount of formaldehyde vapor is generated and it is to be estimated from these test results that it leads to a problem of environmental pollution when using this method is applied on an industrial scale.

It follows, therefore, that the method of DT-OS 21 27 313 has the serious disadvantage of generating is affected by formaldehyde, which is not observed in the process according to the invention. Differences in the flame retardant effect can be between the polycondensate specified above and the N.N-oxymethylene bis (phosphonopropion) amides used according to the invention not be observed.

R ₁ O

10

B e i s ρ i e I 2

Samples of a cotton body are modified with that given in the table below N, N'-oxymethylene bis (phosphonopropion) amides treated. The composition of the appropriate Treatment baths and the results of the flame resistance test before and after washing are also given in the table.

The treatment method is as follows: The fabric is taken after the impregnation (80 wt .-% uptake), dried for 4 minutes at 9O ¹ C and 4 minutes at 150 ⁰ C cured.

The cured and dried material is treated with an aqueous 0.2% by weight at 40 ° C. for 10 minutes Sodium alkylbenzenesulfonate solution soaped and then rinsed with water for 5 minutes. This method is repeated five times.

The finally dried fabric is used as a 'solid after washing.

The flame resistance test is carried out according to the Japanese standard industrial measurement method. Japanese Industrial Standards (JIS) -L-1091 A-I. carried out. This test procedure is the 45 ° micro-torch procedure. The test fabric is stretched over a 25 χ 15 cm frame and placed in a combustion test chamber arranged at an angle of 45 '. The micro-burner is ignited, the Fabric heated for 1 minute and the flame time as the length of time from the end of heating to the The point at which the test substance stops flaming is determined. The micro-burner is in one beforehand Has been adjusted so that the length of the flame is 4.5 cm and the tip of the same with the test fabric is in contact. The test fabric is then separated from the frame and the charred Length and charred area determined.

OR ₁

PCH, CHXNHCH ₂ OCH ₂ NHCCH ₂ CH, P

/ ii "ΊΙ Il * | l \

R ₂ O OO OO OR ₂

Treatlumishad Kiev .- "·«

active
MiUd

XO "r, igc

wiiwr

Mcthoxy-

methylol-

mclumin-

solution

LC ^- !

Before washing ver Hamm- To washing Klamm MgCl ₂ • ft H, O \ cr- kohlter / ClI ver ver Time colille area charred kohlter I.iingc (cm ² ) (lake) I.iingc area (lake) learn) 22nd 0 ; -i) (cm ² ) 0 2 7.0 20th 0 7.8 38 0 - 6.8 22nd 0 7.0 22nd 0 6.6 23 0 6.8 20th 0 - 6.6 22nd 0 6.6 25th 0 6.8 21 0 6.7 27 0 6.7 22nd 0 6.9 24 0 - 6.8 22nd 0 6.8 23 0 6.8 23 0 6.8 26th 0 - 6.9 20th 0 7.4 32 0 2 7.0 23 0 7.7 36 0 2 6.6 22nd 0 6.9 29 0 2 6.6 23 0 6.8 31 0 - 6.7 22nd 0 7.0 28 0 - 6.8 7.3 33

CH ₃ ),

C ₂ H ₅ ),
ClCH ₂ CH _{2 I 2}
Cl ₂ C ₃ H ₅ I ₂
B _r CH ₂ CH ₂ ) ₂

C ₈ H ₁₇ J ₂

: h ₃ , c ₂ h ₅

30th
25th
20th
15th

25th
25th
25th
30th
25th
30th
25th
25th
30th
25th

0.5
0.5

8th
8th
8th
8th
0
8th
8th

0.5
0.5

C 1 S ρ I C

I 3

41 μ Paraformaldehyde with a concentration of aldehyde of 80 (jcw .-% willow in 1X1 μ (1.0 mol) Suspended dimethylphosphonopropionamide. That Reaction mixture is adjusted to a pH of 3.0 using p-toluenesulfonic acid and heated to KO "C with stirring. In 2 hours the suspension becomes a clear solution. The solution stirring is continued for 3 hours to complete the reaction. Finally the Reaklion Misehung distilled under reduced pressure to remove water and excess formaldehyde. In this way, 202 g of N, N'-oxidiinethylene bis (dimethylphosphonopropion) amide are obtained with a purity of 97.4%.

A treatment bath for lambproof treatment is then made from an aqueous 35% by weight

Solution of the product obtained according to the above procedure prepared, to which 3% phosphoric acid was added and the treatment is carried out as in Example 2, whereupon there is no odor after Formaldehyde is perceived.

The treated fabric is then lanj for 5 minutes. with an aqueous solution that reveals 0.3% sodium carbonate and 0.3% sodium alkyl benzenesulfonate, soaped. Finally, the substrate is allowed to stand at 60 ° C for 15 minutes using an aqueous solution O.V '/ uiger sodium alkyl benzenesulfonate solution soaped and rinsed for 3 minutes at 50 ° C. and finally after repeating this process five times Dried for 3 minutes at KK) C.

The results of flame resistance for this test fabric are as follows: charred area 20 cm ² : charred length 6.0 cm and flame time 0 seconds.

For this I sheet / .eiehniinnen

Claims (1)

Patent claims: 1. Method of making cellulosic fiber materials fire-proof using of phosphono - propionamide derivatives, characterized by the fact that the cellulose - containing Fiber material in a treatment bath with a 5 to 80% solution of a phosphorus compound of the general formula (I)