3,639,532 tented Feb. 1, 1972

Aal formula ROCHNHCO-, wherein R is alkyl. Therefore, ESTERS AND/OR AMiffs3,639,532 oF ACIDs oF PHos. this invention contemplates compounds having the for PHORUS CONTAINING A GROUP HAVING THE mula (ROCH2NHCO)R’, wherein R is alkyl, R' is ob FORMULA ROCHNHCO tained by removing all or part of the Zerewitinoff active Gunter Oertel, Cologne-Flittard, Hans Holtschmidt, hydrogen from a sulfur free ester or amide of an acid Leverkusen-Steinbuechel, and Wolfgang Carl, Dorma of phosphorus and n is a positive integer, preferably 1-6 gen, Germany, assignors to Farbenfabriken Bayer Ak which corresponds to the number of active hydrogens re tiengesellschaft, Leverkusen, Germany moved from said sulfur free ester or amide of an acid No Drawing. Filed Apr. 23, 1968, Ser. No. 723,584 of phosphorus. In the foregoing formula R is preferably Claims priority, application Germany, Apr. 25, 1967, 10 F 52,234 lower alkyl having 1-6 carbon atoms such as methyl, Int. C. C07f 9/24, C07d 105/02; C08f 45/85 ethyl, propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert U.S. C. 260-923 4 Claims butyl, n-amyl, isoamyl, n-hexyl, 2-hexyl, 3-hexyl and the like. R' preferably represents the radical obtained by re moving one hydrogen atom which is reactive with an ABSTRACT OF THE DISCLOSURE 5 -NCO group (i.e., active as determined by the Zerewi tinoff method) from a sulfur free ester or amide of an Sulfur free esters and/or amides of acids of phosphorus acid of phosphorus having a molecular weight below 600. which contain at least one group having the formula When the molecular weight is above 600 the products ROCH2NHCO-, wherein R is alkyl, useful as additives are somewhat difficult to use as fire-resistant additives. for resins to impart flame-resistance. 20 The alkoxymethyl amide group, ROCH-NH-CO may be linked to the phosphorus acid moiety by a di This invention relates to phosphorus esters and/or rect bond to the phosphorus atom or through a linkage amides and more particularly to derivatives which have as illustrated in the equations below. improved ability to impart flame-resistance to resins and The compounds of the invention can be prepared, for the like. example, by the reaction between a Zerewitinoff active Phosphorus compounds are known to have flame-re hydrogen atom on an ester and/or amide of a sulfur free sistant properties. Many of them can therefore be used acid of phosphorus and an alkoxymethyl isocyanate ac to impart flame-resistance to resins including synthetic cording to the following equation resins and fibers. Thus, it has been known heretofore to use trichloroethyl or dibutyl phosphate as flame-resistant 30 R-H-I-OCN-CH-O-R-> additives for plastics, but these additives diffuse out and '-CO-NH-CH-O-R thus their effect is lost. In addition, some compounds where R and R' have the meanings set forth above. This which may have other utility, as the compounds of Ger leads to the phosphorylated N-alkoxymethylamide of the man Pat. 1,138,977 decompose in a flame or under high type characterized above, in which R" denotes the radi heat to produce noxious fumes and poisonous gases. cal of an ester or amide of an acid of phosphorus and R Others, even if they produce no undesirable by-products, denotes an alkyl radical regardless of which of the dif are themselves poisonous and cannot be used for textiles, ferent types of Zerewitinoff active hydrogen atoms de coatings, foamed plastics and the like for home use. Even scribed below is involved in the reaction. Examples of if all of these disadvantages are overcome, one must de 40 functional groups in esters or amides of acids of phos termine what effect the additive to impart flame-resistance phorus, and their conversion according to the invention will have on the other physical properties of the mate into N-alkoxymethylamide derivatives, are illustrated rial to be made flame-resistant. Many heretofore known schematically in the following equations. phosphorus additives only improve the flame-resistance of a substance at the expense of some other physical prop 45 erty such as color, tensile strength or the like. This is par ticularly true for textiles where one must pay attention -H -- OCN-CH-O-R - –co-NH-CH-O-R to hand, drape, absorbency, dyeing and dye-fastness, strength, durability, washfastness and cost. The hereto -NH2 - OCN-CH-O-R - H-NH-CO-NFH-CH-O-R fore known phosphorus compounds have suffered from 50 HCO-NH -- OCN-CH-O-R - one or more of the foregoing disadvantages. - CO-NH-CO-NH-CH-O-R It is therefore an object of this invention to provide new compositions of matter which do not have the forego -NH-NH -- OCN-CHNO-R - ing disadvantages and can, therefore, be used in the pro -NH-NH-CO-NH-CH-O-R duction of improved fire-resistant materials. Another ob 55 ject of this invention is to provide an improved process H-CO-NH-NH2 - OCN-CH-O-R --> of preparing addition products of esters and/or amides -CO-NH-NH-CO-NH-CH-O-R of acids of phosphorus which are free from sulfur. An O CO-CH other object of this invention is to provide improved fire -ob-bit, - OCN-CH-O-R --> resistant fibers, foils, textiles and the like. Still a further 60 object of this invention is to provide new compositions CO-CH of matter which will impart fire-resistance to plastic prod ucts without affecting their other properties. Still another -ooo-CH-CO-NH-CH-O-R object of this invention is to provide an improved way H-OH -- OCN-CH-O-R - HO-CO-NH-CH-O-R of rendering materials flame proof and/or flame-resistant. Another object of this invention is to provide a fire-resist HCOOH + OCN-CH-O-R -CO HCO-NH-CH-O-R ant polyurethane, polycarbonate, polystyrene and the like. The foregoing objects and other which will become ap H-NH-OH -- OCN-CH-O-R -) parent from the following description are accomplished -NH-O-CO-NH-CH-O-R in accordance with the invention, generally speaking, by providing sulfur free esters and/or amides of acids of 70 phosphorus which contain at least one group having the p-H -- OCN-CH-O-R - p-co-NH-CH-O-R

38.35 s 3,639,532 3 The functional groups in the above scheme can be C3 --- W N N / linked to the phosphorus atom of the ester or amide of - P-NH2, N-- - EP-NH-CH phosphorus through carbon, oxygen, nitrogen or direct w 2 / ly. One example of a direct link between the Zerewitinoff C H3 2 active hydrogen atom and the phosphorus atom is found 5. O O in the reaction, formulated in the last of the above equa tions, between a PH acid compound, e.g., a phosphorus acid diester, -diamide or -ester amide, and an alkoxymeth ylisocyanate. Esters and amides of acids of phosphorus which may O Yao be used as starting in the process according to the inven O O tion may contain one or more Zerewitinoff active hydro d HCH3OHE. : ICH2OH./ gen atoms which may be of the same type or different; for example, OH groups may be present together with NH groups, or PH groups may be present in the same molecule. C6H5 O CEI C2H5 O Furthermore, not all the Zerewitinoff active hydrogen / V atoms present in an ester or amide of an acid of phoS P--NH. P-CH OFI phorus need be reacted with alkoxymethylisocyanates. CHO CH3 C2H5O They may, in fact, react selectively and partially, espe 20 CH 9 / cially if they have different reactivities. P-CH-NH-... Cls The sulfur free esters or amides of acids of phosphorus Cl5O C.H. that may be used as starting materials for the reaction according to the invention are mainly esters and amides CHO / of phosphinous, phosphinic, phosphonous, phosphonic, F--CH2-CH2. OI phosphorous and phosporic acids. Any of these phosphorus / compounds may be used for the reaction with alkoxy CHO methylisocyanates, provided they have Zerewitinoff active / o hydrogen atoms in the molecule, e.g., in the form of the (NH-CH-CH-CH2-), P-N (-CH3)2 substituents mentioned by way of example in the above 30 scheme. It is essential, however, that the compounds be y free of sulfur because sulfur not only makes the com C.H.--O-(CHCH-0)-H, C.H.--0 CH3 pounds toxic and unsuitable for many uses, for example, H where they are used to flameproof substances that come W in contact with food, but also where the substance may be 35 y subjected to a fire. The sulfur-containing compounds react CEI -- (--OCEI-CH-CH2--CI-NH2) O with oxygen in a fire to produce noxious gases that are / | almost as harmful as the fire itself NH-CO-CH-P (-O C.IIs), Table I lists examples of sulfur-free esters of phos O O O CH phorous acids, wherein it will be noted that the compounds 40 I / / / (CH3O-)2P-CHCH-COOH, FFO-C-P have a total of 4 to 18 carbon atoms as benzene rings, 4 N.Y. straight or branched chain hydrocarbon groups of from CH3 CH3 OH 1 to 6 carbon atoms, and such hydrocarbon groups (1) O O CHs interrupted with a nitrogen or oxygen atom, or (2) sub M stituted with a hydroxy, amino, chloro or bromo group. 45 (CH3-)2N-CH-P The from 1 to 3 Zerewitinoff hydrogens that can be re OH placed are indicated by (V). / TABLE O O O Y / C.H.0-p-O-(CH)-o-p-o C2H5, H-P-O-(CII2) s-OH), H y / ? / o (Br-( >-o-, -, Cicilich,--O-CHCH-O-CHCH-O--ochschicE. v / O O | / H / ((FIs () -), P -- () , (to sp-o-c-ligh-cl. -Oil, OH / y Q / Nl CIC -o-p O PIO C : C 12)-3-OH)3, O O (.' I y (ir. (Ely ('H'-O-), P -- () -- CII ( II () I., O () i clo-ciscIl-..N. P. (). (E - CE - 3 - C1, 31), P( - Nil--C Ely CH-N) 3,

/ W (((ICEL) - ) iP-N12, Niig ( () - N - (- - O Colis); 3,639,532 5 6 TABLE I-Continued 22 is 2 O O O C Cl--(o-CHCHCHCH-of:/ Cichoh-0--0-(CH2-0--0-CHCH.Cl / O NH-CH2CH-P (-O C2H5) V (C.H.0-)-b-CH-N(CH-CH-0). Q H 9 O (C.H.0-, -d-: (-0 C2H5)2 (C.H.0-), B-CH-N (-CHCHCH-NH). 10 H3 O O=P(OCH) V / 2 Ho--CHCHCH ... O H. (C.H.0-lb-N(-CHCHCH-NH). O=P(OCH3)2 Any suitable alkoxymethylisocyanate may be used. 15 The alkoxymethyl isocyanates may be prepared as de scribed in German patent specification 1,205,087. The preferred alkoxymethylisocyanates are those which con O O C2H5 O / I/ | NIH, - . (CH2)3 -P coll-H-ecocil), ONa OHV O O ! / / CH=CH-CH-P(OCHCHCl),OHy Ho-CH-P(OCHCI)--OH), O O CH5-N=C-NH-CH5,w NH-CO-P(OCH3)2,W (H, CH-OH,-| (OCH) o-h (OCH) OH, OH V /

O O

NH / CH3 O CH3 O NH-C-P(OCH3)2,É-d-: HO/ -CH2CH2-N-CH-P(OCH5) H3 O CH3 O O CH3 V V / C.H.--NH-CH-CH-OH, (HO-CHCHO-)P-CHCH-P (-O CHCH-OH), OH. O O O v V / / / HO-P-O-CHCH-OH, H-P (-OCH2CH-OH), H-P (-O CHCHCl). H/ / 9-H. / 9-H. / 0-CH CH-0.9 V / g CH, --- K , H-P , H-P /N e-It, H-e-N O-CH N-CH, O- CH CH-O CFI3/ CH3 For convenience, Table II summarizes the radicals ob tain 1 to 6 carbon atoms in the alkoxy group, such as tained by removing Zerewitinoff hydrogens from the phos methoxy, ethoxy, propoxy, n-butoxy, 2-butoxy, isopro phorous acid compounds used in the examples. 60 poxy or n-hexyloxymethylisocyanate. Methoxymethyl TABLE II isocyanate is most preferably used. 2 is In view of the great number of possible starting g materials and their physical and chemical properties, the - P (-O CTI), -P(OCTI), (CH3O ...) P pH (). -- reaction conditions under which the reaction according to the invention is carried out may vary within certain CCl3 65 limits. The reaction is preferably carried out at tempera O O O tures from about -50 to about 180 C., most preferably -P| (-O-CH2CH2Cl), -P(-O1. CHCH-CH2)2, -P(OCH)! at about 10 to about 100° C., in bulk, solution, suspen CH3O O O CH sion or emulsion. N l Any compounds that are inert to isocyanates may be P-(CH), Nit -, (CH3O-) --O- 70 used as solvents or diluents. These include, for example, NO CH3 (chlorinated) hydrocarbons, ethers, esters, ketones, di alkylcarboxylic acid amides, sulphones, sulphoxides or nitriles. If, however, the Zerewitinoff active groups con (CHO)2P-CHO or (CH,0-)-p-pit-0) tained in the phosphorus compound which is to be reacted CH 75 with the alkoxymethyl isocyanate contains basic primary 3,639,532 7 8 or secondary amino or hydrazino groups, then the reaction dibutylphosphate can easily diffuse out of the synthetic may also be carried out in solvents or diluents which resin owing to their high vapor pressure, this not possible contain hydroxyl groups, for example, alcohols or water, in the case of the "functional' flame-protective agents since in this case the isocyanate reacts selectively with obtainable by the process according to the invention. This the more highly reactive amino groups. 5 effect is of special interest in its application to textiles One may either place the isocyanate in solution or in where the large surface area of the fibers greatly promotes bulk in the reaction vessel and add the phosphorus com the evaporation of volatile flame-protective agents. In ad pound thereto, either in bulk or in solution or emulsion dition, flame-protective finishes applied to fibers or tex or suspension, or add the isocyanate to the phosphorous tiles in the form of simple esters or amides of acids of compound. Depending on the type of end product re 10 phosphorus are generally not resistant to washing. Owing quired, the alkoxymethyl isocyanate may be added either to the possibility of reacting on or in the fiber with them in stoichiometric quantity or in excess or in less than selves or with other reactive groups through the N-alkoxy the stoichiometric quantity relative to the quantity of methyl groups to produce higher molecular weight prod Zerewitinoff active hydrogen atoms in the phosphorus ucts, the substances obtained by the process according to compound. Excess isocyanate can easily be removed after the invention are distinguished by exceptionally high re the reaction by heating the reaction products or their sistance to washing if suitably applied. solutions, preferably under reduced pressure. For the reasons given above, the new products described The reaction according to the invention in many cases hereinabove all have flame-protective properties when proceeds satisfactorily even in the absence of catalysts. applied to fibers and foils, for example, of polyacryloni In some cases, however, it is advisable to add the known 20 trile, polyamide, polyesters, cotton and wool. One special catalysts for isocyanate reactions, such as tertiary amines, advantage they have is that they are effective even at low alkali metals or alcoholates, organo tin compounds and concentrations. They reach their maximum effectiveness metal salts preferably in quantities of 0.001 to 1.0% to at applications of only 3 to 15% on the fiber, preferably the reaction mixture. 4 to 6% (based on the weight of fiber) or when added in The esters and amides of acids of phosphorus obtain amounts of 10 to 15% to polymers, able by the process according to the invention are char Another advantage of the products which can be pre acterized, as already explained initially in this text, by pared according to the invention is that they do not affect the presence of one or more groups of the general any of the properties of the articles treated or of the formula polymers provided with additives other than the com R-O-CH-NH-CO bustibility. in the molecule, wherein R denotes an alkyl radical. This The invention is further illustrated by the following N-alkoxymethylamide group, when bonded to a sulfur examples in which parts are by weight unless otherwise free phosphorus ester or amide, distinguishes the products specified. of the process from all known phosphorus compounds EXAMPLE 1. and imparts special, commercially valuable properties to them. As is well known, almost all organic phosphorus com pounds have a flame resistant character or are non-com About 3095 g, of methoxymethyl isocyanate are added bustible. Many of them are, therefore, also used as flame 40 at about 30 to about 40° C. to a solution of about 74 g. protective additives for easily inflammable synthetic resins of sodium diethylphosphite in about 4910 g. of diethyl and fibers. However, the phosphorus compounds function phosphite. An exothermic reaction takes place. The tem by forming a char by-product when burned and this prod perature of the mixture is maintained between about 30 uct or by-products of its formation must not itself be and about 50° C. by external cooling with water and the toxic. reaction mixture is then stirred for about one hour at N-alkoxy groups, especially N-methoxymethyl groups, about 50 C, and is degasified for about 30 minutes under are known to be capable of reacting with themselves or reduced pressure (water jet pump) at about 60° C. to with OH or NH groups when heated, especially in the remove traces of unreacted starting materials. presence of acids, alcohol being split off and the reaction The yield is about 8.0 kg. of a colorless liquid of re resulting in an increase in molecular weight, and finally fractive index n0: 1.4504. in cross-linking or, when high molceular weight com 50 The infra-red spectrum of this substance shows char pounds which themselves contain the last mentioned acteristic bands for CO at 1670 cm.-1, for POC at 1030 groups are present, the reaction results in condensation cm.1 and for CHOCH at 1070 cm.-1. of the compound containing the N-methoxymethyl radi If polyacrylonitrile fiber flock or fiber yarn is treated cals with the high molecular weight product. 55 at room temperature with aqueous solutions of the above The esters and amides of sulfur free acids of phosphorus mentioned compound (concentrated 240 g/l.) centri obtainable by the process according to the invention thus fuged to reduce the moisture content to about 25% and represent valuable flame protective agents for use in the dried at about 120° C., they show a considerable reduc production of all sorts of different resins. They are suit tion in combustibility, able, inter alia, for providing flame protective finishes to 60 shaped articles such as foam plastics, films, lacquers and EXAMPLE 2. fibers made of different types of materials such as poly O urethane, polycarbonate, polystyrene, polyethylene poly vinyl acetate, cellulose, etc. The polyurethanes may be Cis-O-CH-NII--CO-I (.-. OCII) prepared by the process discloses in U.S. Reissue Pat, A Spatula tip of sodium methylate is added to an emul 24,514 and polyarylcarbonates are preferred and may be Sion of about 275 g. of dimethylphosphite in about 300 prepared by the process of U.S. Pat. 3,028,365. The new ml. of ligroin, and about 218 g. of methoxymethyl iso products are distinctly superior in their fame protective cyanate are then slowly added dropwise at about 40 to effect to the esters and amides of acids of phosphorus 60° C. to the reaction mixture. The temperature of the previously used for this purpose. Their special advantage 70 reaction mixture is maintained within the given range by is that they can be firmly linked to the substrate, for ex cooling with ice water, and the reaction is taken to com ample, to the synthetic resin, through their N-alkoxy meth pletion by heating the mixture at about 80 to 90° C. for yl groups by heat treatment and/or the actions of acids about 2 hours. The reaction product separates as oily (shown in the working examples below). Whereas the phase from the ligroin solution. It is separated and dried usual flane protective agents such as trichloroethyl- or 5 under reduced pressure at about 50° C. 3,639,532 10 About 493 g. of a colorless liquid of refractive index EXAMPLE 8 n20=1.4535 are obtained. EXAMPLE 3 (CHO-)P-CH-N(-CH-CH-O-CO-NH-CH-O-CH3)2 g 5 About 174g. of methoxymethyl isocyanate are added (CH,0--P-GH-o-c O-NH-CH-O-CH dropwise, with stirring, to about 255 g. of O,O-diethylester CCl3 of N,N-di-(2-hydroxyethyl)-aminomethylphosphonic acid About 24.15 g. of ox-hydroxy-6,6,3-trichloroethylphos at about 40 to about 50° C. When the very strongly exo phonic acid, O,O-dimethylester are dissolved in about thermic reaction has died down, the mixture is stirred 50 mi. of methylene chloride. About 0.5 ml. of triethyl 0 for about 4 hours at room temperature and is then de amine is added to the solution and thereafter about 9 g. gassed at reduced presure. About 429 g, of a yellow oil of methoxymethyl isocyanate are added dropwise at about of refractive index n0=1.4700 are obtained. 30 to about 40° C. with external cooling. When the exo By adding about 12% of the above compound to poly thermic reaction that sets in has died down, the resulting 5 mer solutions, e.g. of polyacrylonitrile in dimethylform clear solution is heated to boiling for about one hour amide which are then worked up into foils or filaments, and then concentrated by evaporation under reduced pres the combustibility of these products can be greatly re sure. About 33 g, of a yellow oil remains behind which duced. crystallizes when left to stand for some time. Solvent was EXAMPLE 9 removed by pressing the crystals on clay and they were 20 CHO) dried at about 40 to about 50° C. under reduced pressure. P-(CEI) 3-NFI-CO-NH-CH-O-CE: About 17 g. of colorless crystals of melting point about NaO - 91 C. are obtained. About 48.5 g. of methoxymethyl isocyanate are slowly EXAMPLE 4 added, with cooling, to a solution of about 98 g. of the O 25 sodium salt of 3-aminopropylphosphonic acid methyl CH-O-CH-NH-C o- (-O CH3CH=CH) ester in about 100 ml. of ethanol, at about 0 to 10 C. The reaction mixture is then concentrated by evapora From about 310.5 g. of {3,3-dichloroethylphosphite and tion in a rotary evaporator under reduced pressure at about 135 g. of methoxymethyl isocyanate, about 430 g. about 50° C. About 146 g. of the above compound remain of the above compound are obtained by the method used 30 in Example 1 in the form of a colorless liquid having a in the residue in the form of a colorless, viscous oil. refractive index of n20-1.4855. EXAMPLE 10 EXAMPLE 5 (C2H5O-)2P-CH-N(-CH2CHCH-NH-CO-NH-CH-O CH) 35 About 127 g. of the O,O-diethyl ester of N,N-di-(3- CH-O-CH-NH-CO-P (-O CH3CH=CH2) aminopropyl)-aminomethylphosphonic acid are reacted About 582 g. of the compound of the above formula are obtained in the form of a reddish liquid of refractive in ethanolic solution with about 78.5 g. of methoxymethyl index n0=1.4722 by reacting about 380 g. of diallyl isocyanate by the procedure described in Example 9. phosphite and about 205 g. of methoxymethyl isocyanate 40 About 205 g. of the above compound are obtained as by the method described in Example 1. reaction product in the form of a brown, viscous oil. EXAMPLE 11. EXAMPLE 6

CH3-O-Cha-NH-CO-P (-O C4H) 45 About 141 g of the above compound are obtained in About 113.g. of phosphoric acid, O,C-diethyiester N. the form of a colorless liquid (n20=1.4510) from about di-(3-aminopropyl)-amide are reacted with about 74 g. 97 g. of dibutyl phosphite and about 43.5 g. of methoxy of methoxymethyl isocyanate in ethanol in a manner methyl isocyanate by the method described in Example 3. analogous to that used in Example 9. About 184 g. of Analysis.--Molecular weight: 281. Calculated (per 50 a reddish, viscous oil are obtained. cent): C, 47.0; H, 8.55; P, 11.0. Found (percent): C, EXAMPLE 12 47.1;H, 8.63; P, 10.8. O CH EXAMPLE 7 (CHO). F-C-O-co-NH-CH-O-ch, 55 O O ÖH, - . . About 75 g of O,O-dimethylester of 2-hydroxypropyl CICHCH-O-P-O-(CH-0--0-ch.ch.c. 2-phosphonic acid are dissolved in about 200 ml. of aceto go go nitrile. After the addition of about 0.1 g. of tin-(II)- NH-CH-O-CH NH-CH-O-CH3 dioctoate, about 38.8 g. of methoxymethyl isocyanate 60 are added dropwise to the solution at room temperature, To about 185.5 g. of the phosphoric ester of the fol and the reaction mixture is then heated to about 70° C. lowing formula for about one hour and concentrated by evaporation un O O der reduced pressure. About 100 g. of the above com pound remain behind in the residue in the form of color Cl-CH2--CF- 0--0 -(CII)6- O - -o-c F-CH.Cl 65 less crystals which melt at about 58 to 60° C. after H H reprecipitation in a mixture of benzene and ligroin, a spatula tip of sodium diethylphosphite is first added EXAMPLE 13 followed by about 87 g. of methoxymethyl isocyanate O added dropwise at about 50° C. with external cooling 70 and vigorous stirring. The mixture is then stirred for about (CH3O)2P-CH-O-CO-NH-CH-O-CH one hour at about 60 to about 70° C. and is finally de About 140 g. of the O,O-dimethylester of hydroxy gassed under reduced pressure. methylphosphonic acid are reacted with about 87 g. of About 272 g, of a colorless oil of refractive index methoxymethyl isocyanate by the procedure described in nD=1.4819 are obtained. 75 Example 12, and about 500 g. of the above compound 3,639,532 2 are obtained as reaction product in the form of a yellow 2. As a flame-retarding agent adapted to incorporation oil. into a plastic composition, a sulfur-free phosphorylated Starting from the O,O-dibutyl ester of hydroxymethyl N-alkoxy-methylamide of the formula phosphonic acid and methoxymethyl isocyanate, the cor responding N-methoxymethylurethane is obtained as a 5 (ROCHNHCO)R’ colorless liquid of refractive index n0=1.4521. wherein: EXAMPLE 14 n is an integer from 1 to 3; O R is an alkyl of 1 to 6 carbon atoms; and R’ is a radical obtained by removing the Zerewitinoff hy (clo-sh-CH- O. CO --Ni-Ci-. O. CI O drogen from one of di-ethoxyphosphonic acid ester of cii, hexamethylene glycol, di-hexamethylene glycol ester of phosphonic acid, di-p-bromophenyl ester of phosphinic About 368 g. of methoxymethyl isocyanate are added acid, di-chloroethylphosphinic acid ester of diethylene at room temperature to about 652 g. of O,O-dimethylester glycol, di-ethyl phosphate, mono-1-glyceryl phosphate, of 1 - hydroxyethyl-1-phosphonic acid in the presence of 5 mono-aminoethyl phosphate, tri-(di- or tri-ethylene about 1 g, of tin-(II)-dioctoate. When the slightly ex glycol) phosphate, di-bromoethyl-mono - 2-hydroxy othermic reaction has died down, the reaction mixture propyl phosphate, mono-(di-hydroxyethyl-amido)-di is stirred for about one hour at about 70° C. and is then (2,3-dibromopropyl) phosphate, tri-amino-ethylamino degasified at this temperature under reduced pressure. phosphoramide, mono - (di - aminopropyl-amido)-di About 991 g. of a yellow liquid of refractive index 20 ethyl phosphate, phenylphosphonic acid diamide, di n0=1.4543 are obtained. chloroethoxy phosphoramide, N-diphenoxyphosphoryl EXAMPLE 1.5 urea, di-phenyl-amino-phosphine, di-(dimethylamino-p- The following example illustrates the use of compounds phenyl) - methylamino-phosphine, diethyl-phosphinic of the invention to impart flame resistance to cellular poly acid hydroxyethyl mono-ester, dimethyl-phosphonic urethane plastics: acid amide of hydrazine, 1,2 - ethane-bis-(phenylphos About 85 parts of a mixture of about 65 parts of the phinic acid-mono-hydroxy ethyl-ester), ethylphosphinic propylene oxide adduct of 1,1,3-para-hydroxyphenyl pro acid di-hexamethylene glycol ester, 2 - aminopropyl pane having a hydroxyl number of about 223 and about phenylphosphinic acid ethyl ester, hydroxymethyl-eth 35 parts of the propylene oxide adduct of glycerine hav 30 ylphosphinic acid ethyl ester, or - methylaminobenzyl ing a hydroxyl number of about 652 mixed with about methylphosphinic acid ethyl ester, hydroxyethyl-butyl 15 parts of the propylene oxide adduct of diethylene tri phosphinic acid propyl ester,di-(aminopropyl) phos amine having a molecular weight of about 400 and a phinic acid dimethylamide, ethylphosphinic acid (di hydroxyl number of about 700 and 30 parts of the com or tri - ethyleneglycol) monoester, phenylphosphinic pound according to Example 14 are combined on a ma acid monomethyl ester, phenyl phosphorus acid di chine mixer as disclosed in Reissue Pat. 24,514 with about aminobutyl ester, amidocarboxylmethylphosphonic acid 109 parts of the organic polyisocyanate obtained by the diethyl ester, carboxyethylphosphonic acid dimethyl phosgenation of the condensation product of aniline and ester, 2 - hydroxypropylphosphonic acid monomethyl formaldehyde which has an amine equivalent of about ester, dimethylaminomethylphosphonic acid monoethyl 140 and which contains about 31 percent free -NCO 40 ester, trichloromethylphosphonic acid di-hydroxybutyl with about 40 parts of trichlorofluoromethane, about 1.1 ester, aminoethylphosphonic acid diethyl ester, 1 - hy parts of 1-methyl-4-dimethyl amino ethyl piperazine and droxy - 1,1-di(diethoxyphosphonyl)-ethane, 1, 1 -di about 1 part of a silicone oil having the formula (dimethoxyphosphonyl) - butylene glycol - 14, trichlo romethylphosphonic acid diamide, monosodium-mono CH ethyl aminopropylphosphonate, 1-hydroxy-2-trichloro 45 ethylphosphonic acid dimethyl ester, 1 - hydroxyallyl cut- (", \e nEanO)30 o phosphonic acid di-dichloroethyl ester, hydroxymethyl L \ H3 J6 3 phosphonic acid di-(di- or tri-ethylene glycol) ester, wherein (CH2O) is a mixed polyoxyethylene and oxy ethylamino-ethylamino-methylphosphonic acid diethyl propylene block copolymer containing about 17 oxyethyl 50 ester, carbamylphosphonic acid dimethyl ester, 2,3 di ene units and about 13 oxypropylene units. The foam hydroxypropylphosphonic acid diethyl ester, di- (amino rises in about 100 seconds and is tack-free in about 3 propyl)-aminomethylphosphonic acid diethyl ester, 3 minutes. This foam is self-extinguishing when subjected aminophenyl-phosphonic acid diethyl ester, p-hydroxy to a flame. phenylphosphonic acid dimethyl ester, tri-(4 amino What is claimed is: 5 5 phenyl) phosphate, 2-aminoisopropyl-phosphonic acid 1. As a flame-retarding agent adapted to incorporation dimethyl ester, N-hydroxyethyl-N-methyl-aminometh into a plastic composition, a sulfur-free phosphorylated yl-phosphonic acid diethyl ester, phenylphosphonic acid N-alkoxy-methylamide of the formula hydroxyethyl - amide, 1,2 - ethane-bis-phosphonic acid tetra - (2 - hydroxypropyl)-ester, mono-hydroxyethyl (ROCHNHCO)R’ 60 phosphite, di-hydroxyethyl phosphite, di-chloroethyl wherein: phosphite, cyclic ethyleneglycol phosphite, phosphorous R is an alkyl of 1 to 6 carbon atoms; acid cyclic ester amide of 2-methylaminoethanol, di R" is a radical obtained by removing a Zerewitinoff hy phosphorous acid ester of pentaerythritol, phosphorous drogen from a sulfur-free compound selected from the acid di-(dimethylamide), diethyl phosphite, dimethyl group consisting of amides and esters of an acid of phosphite, 1 - hydroxy - 2 - trichloroethylphosphonic phosphorus, said compound having a molecular weight acid dimethyl ester, di-chloroethyl phosphite, di-allyl below 600 and from a total of 4 to 18 carbon atoms as phosphite, di-butyl phosphite, aminopropylphosphonic benzene rings, straight or branched hydrocarbon groups acid mono-sodium salt mono-methyl ester, 2 - hydroxy (1) interrupted with a nitrogen or oxygen atom, and isopropylphosphonic acid dimethyl ester, hydroxymeth (2) substituted with a hydroxy, unsubstituted amino, 70 yl-phosphonic acid dimethyl ester, 1-hydroxyethylphos lower alkylamino, hydroxy lower alkylamino, amino phite diester of hexamethylene glycol, di-(hydroxyeth alkylamino, lower alkylimino, chloro or bromo group; yl)aminomethylphosphonic acid diethyl ester, di and (aminopropyl)aminomethylphosphonic acid diethyl es n is an integer from 1 to 3 and corresponds to the num ter, and phosphoric acid diethyl ester (diaminopro ber of said Zerewitinoff hydrogens so removed. 5 pyl)-amide. 3,639,532 13 14 3. The agent of claim 2, wherein R is methyl. 4. As a flame-retarding agent adapted to incorporation methylphosphonic acid diethyl ester, di-(aminopropyl) into a plastic composition, a sulfur-free phosphorylated N aminomethylphosphonic acid diethyl ester, and phos alkoxy-methylamide of the formula: phoric acid diethyl ester (di-aminopropyl)-amide. References Cited wherein: (CH-OCH-NHCO) R' UNITED STATES PATENTS n is 1 or 2, and 2,909,558 10/1959 Reetz ------260-943 R’ is a radical obtained by removing the Zerewitinoff hy 3,048,613 8/1962 Ladd et al. ------260-943 drogen from one of diethyl phosphite, dimethyl phos 10 3,069,312 12/1962 Kohn ------260-938 X 1 - hydroxy - 2 - trichloroethyl-phosphonic acid dimeth yl ester, di-chloroethyl phosphite, di-allyl phosphite, di CHARLES B. PARKER, Primary Examiner butyl phosphite, aminopropylphosphonic acid mono-So ANTON H. SUTTO, Assistant Examiner dium salt mono-methyl ester, 2-hydroxyisopropylphos phonic acid dimethyl ester, hydroxymethylphosphonic 5 U.S. C1, X.R. acid dimethyl ester, 1 - hydroxyethylphosphite diester 8-115.5, 116 P; 106-15 FP; 260-2.5 AJ, 551 P, 45.7 of hexamethylene glycol, di - (hydroxyethyl)amino P,928,929,932, 936,937,938,943

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