CH493563A - Phosphornitrile esters - for flameproofing plastics and treating textiles - Google Patents

Abstract

Spirocyclic phosphornitrile esters useful for flame-proofing plastics, as heat-stabilisers, anti-statics and textile crease-proofing agents are produced by reacting 1 mole phosphornitrile halide with 3 moles propane-1,3-diol R2R1C(CH2OH)2 (where R2 and R1 are 1-5C alkyl) and have formula:-.

Description

  

  
 



  Process for the preparation of phosphonitrile spirocyclic phosphonitrile esters of the formula
EMI1.1
 in which the benzene nuclei A can still be substituted have already been prepared from trimeric phosphonitrile chloride and ortho-dihydroxybenzenes (cf. USA Patent No. 3,294,872).



   In contrast, corresponding spirocyclic esters of the aliphatic series have only been described for a few substituted glycols, namely for 2,2-bis (nitratome thyl) -1,3-peranediol (MS Chang and AJ Matuszko, Chem. Ind. London], [1962 ], 410) and for 1,4-tetrafluorobutanediol or 1,5-hexafluoropentanediol (H. Schrotder et al., J. Amer. Chem. Soc. 84 [1962], 551).



   These phosphonitrile esters correspond to the formula
EMI1.2
   where K
EMI1.3
 or
EMI1.4
 and n is 2 or 3.



   No other examples are known. In particular, ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol and 1,6-hexanediol do not form spirocyclic esters with trimeric phosphorus trilchloride (A. J. Matuszko and M. 8. Chang, 1st erg.



  Chem. 31 [1966], 2004).



   It has now been found that spirocyclic esters of the formula
EMI2.1
 obtained, in which each of the symbols R2 and R3 signifies a low molecular weight unsubstituted alkyl radical, if 1 mol of a trimeric phosphonitrile halide is mixed with 3 mol of a propane-1,3-diol of the formula
EMI2.2
 implements.



   Trimeric phosphonitrile halide can e.g. B. by reacting ammonium halides with phosphorus pentahalides, preferably NH4Cl with P Cls, and fractional distillation of the resulting mixture.



   The radicals R2 and R3 can be identical or different from one another and contain 1 to 5 carbon atoms (methyl, ethyl, n-propyl, isopropyl, n-butyl). Preferably R2 and R3 are both methyl radicals.



   As propane-1,3-diols of the formula (w), z. B. the following into consideration: 2,2-diethylpropaneq 3 diol, 2-methyl-2-n-propyl-propane-1,3-diol, 2-ethyl-2-n-butylpropane-1,3-diol and especially 2 , 2-dimethylpropane-1,3-diol.



   It is advantageous to work in an organic solvent which is inert to the phosphonitrile halide and in the presence of an acid-binding agent in the temperature range from -50 ° C. to 200 ° C., preferably in the range from 0 to 1000 ° C., optionally under elevated or reduced pressure.



   Suitable organic solvents are e.g. B. ethers such as dioxane, 1,2-dimethoxy or diethoxyethane, 1-ethoxy-2- (2'äthoxyäthoxy) -ethane, tetrahydrofuran, aromatic hydrocarbons such as benzene, toluene, xylene, mesitylene, halogenated aliphatic or aromatic hydrocarbons such as chloroform, trichlorethylene , Chlorobenzene, ortho-dichlorobenzene, bromobenzene, ketones such as propanone-2, butanone-2, pentanone-3, 4-methyl-pentanone-2, 2, 6-dimethyl-heptanone-4, also acetonitrile, dimethylformamide and -acetamide, dimethyl sulfoxide , Tetramethylene sulfone, phosphoric acid wtris (dilmethylamide) etc.



   As acid-binding agents come such. B. considered: alkali metal hydroxides and carbonates such as potassium, sodium or lithium hydroxide or carbonate, alkaline earth metal hydroxide and carbonates such as calcium, magnesium or barium hydroxide or carbonate, ammonium hydroxide or carbonate, quaternary ammonium hydroxides such as benzyltrimethyl, tribenzylmethyl or tetra (lower alkyl) ammonium hydroxide, guanidines and biguanides such as hexa- or hepta (lower alkyl) biguanide, tetra (lower alkyl) guanidine, tri- (lower alkyl) amines such as Triethylamine, tributylamine or trimethylamine, pyridine, etc.



   If tertiary amines are used as acid-binding agents, these can also serve as solvents.



   About 3 moles of the 1,3-ziol propane of the formula W are normally used, a small amount of oil generally not doing any harm.



   Man. can often allow the reaction to proceed at a relatively low temperature and, if necessary, heat at the end in order to complete the reaction.



   When the reaction is complete, you can add the reaction product z. B. by diluting with a suitable agent, preferably with an alcohol such as methanol, ethanol, isopropanol, precipitate and suction and dry. You can also remove the solvent by distillation, preferably under reduced pressure and remove the solid residue with a suitable agent, for. B. methylene chloride, or chloroform extract.



   If a tertiary amine is used as a solvent and as an acid-binding agent, the reaction mixture can also be poured into acidified water and the ester that has separated off can be filtered off with suction, washed neutral and dried.



   The resulting phosphonitrile esters of the formula (III) are distinguished from the open-chain aliphatic esters of trimeric phosphonitrile chloride, e.g. B.



  against hexaethyl - (- propyl, butyl, methyl u.



  estern through a very strong increase in thermal stability. While the aliphatic open-chain esters mentioned are mostly liquids that decompose between 100 and 2000 C, the phosphonitrile esters are thermally stable, mostly crystalline substances that are soluble in some solvents such as methylene chloride and chloroform.



   The products obtained serve as flame retardants for plastics, e.g. B. synthetic resins, as antistatic agents, heat stabilizers and agents for the anti-crease finish of textiles.



   In the following example, parts are parts by weight and percentages are percentages by weight.



   The temperatures are given in degrees Celsius.



   example
A mixture of 11.6 parts of trimeric phosphonitrile chloride and 10.4 parts of 2,2-dimethylpropane 1,3-diol in 100 parts of pyridine is stirred at 25 for 48 hours. Then pyridine is distilled off under reduced pressure and the remaining solid residue is extracted with methylene chloride. The residue remaining after the methylene chloride has been evaporated is washed out with ethyl acetate and then recrystallized from a methylene chloride-ethyl acetate mixture.

 

   Analysis: Ber. (C15H30N3O6P3)
C: 40.8 H: 6.9 N: 9.5 P: 21.1 Found. C: 40.9 H: 6.8 N: 9.2 P: 21.4
The spirocyclic phosphonitrile ester obtained, the structure of which is secured by means of the IR spectrum and NMR spectrum, is in some solvents, e.g. B. chloroform and methylene chloride, soluble and does not melt at temperatures up to 300.

 

Claims (1)

PATENT CLAIM I. Process for the preparation of phosphoinitrile esters of the formula EMI3.1 characterized in that 1 mol of a trimeric phosphorus nitrile halide is mixed with 3 mol of a propane 1,3diol of the formula EMI3.2 implements. II. Use of the phosphonitrile esters produced by the process according to claim I for protecting plastics against heat and flames. SUBClaim Process according to patent claim I, characterized in that 1 mol of trimeric phosphonitrile chloride is reacted with 3 mol of 2,2-dimethylpropane-1,3-diol.