DE102010040632A1 - New oligophosphorus compounds, useful as flame retardant in foamed or defoamed polymers, preferably polystyrene foam particles of expandable polystyrene or extruded polystyrene foam panels, which are useful for insulation of buildings - Google Patents

Abstract

Oligophosphorus compounds (Q), are new. Oligophosphorus compounds (Q) of formula (P(R 1>)(R 2>)(=X)-P(R 3>)-P(R 4>)(R 5>)) (Ia), (P(R 1>)(R 2>)-P(R 3>)(=X)-P(R 4>)(R 5>)) (Ib) or (P(R 1>)(R 2>)(=X 1>)-P(R 3>)-P(R 4>)(R 5>)(=X 2>)) (Ic), are new. R 1>-R 5>1-16C-alkyl, 1-16C-alkenyl, 1-16C-alkoxy, 1-16C-alkenyloxy, 3-10C-cycloalkyl, 3-10C-cycloalkoxy, 6-10C-aryl , 6-10C-aryloxy, 6-10C-aryl-1-16C-alkyl, 6-10C-aryl-1-16C-alkoxy, NR 2>R 3>, COR 2>, COOR 2>or CONR 2>R 3>; and X 1>, X 2>O or S. An independent claim is included for the preparation of (Q).

Description

The invention relates to oligophosphorus compounds, processes for their preparation and their use as flame retardants.

Currently, as flame retardants in plastics mainly polyhalogenated hydrocarbons, optionally used in combination with a suitable synergist, such as expanded graphite. A typical representative of these classic flame retardants is hexabromocyclodecane (HBCD), which is used, for example, in polystyrene. Due to bioaccumulation and persistence of some polyhalogenated hydrocarbons, it is a major effort in the primary industry to substitute halogenated flame retardants.

Flame retardants should, if possible, in addition to a high flame retardancy in the plastic at low loading for processing also have sufficient temperature and hydrolysis stability. Furthermore, they should have no bioaccumulation and persistence.

Flame retardant polymer foam finishing is important for a variety of applications, such as expandable polystyrene (EPS) or expanded polystyrene (XPS) expanded polystyrene foam for building insulation. For polystyrene homopolymers and copolymers, mainly halogen-containing, in particular brominated, organic compounds have hitherto been used. However, a number of these brominated substances are under discussion due to their potential environmental and health hazards.

The US 4,111,899 describes cyclic or alicyclic Oligophosphorverbindungen with one or more PP bonds, which are used in amounts of about 1000 ppm for the stabilization of thermoplastics, especially polycarbonates, in heat and / or oxygen injection molding.

Halogen-free flame retardants must be used to achieve the same flame retardancy of halogen-containing flame retardants usually in significantly higher amounts. Therefore, halogenated flame retardants that are useful in thermoplastic polymers such as polystyrene often can not be used on polymer foams because they either interfere with the foaming process or affect the mechanical and thermal properties of the polymer foam. Moreover, in the production of expandable polystyrene by suspension polymerization, the high levels of flame retardant can reduce the stability of the suspension.

The effect of the flame retardants used in thermoplastic polymers in polymer foams is often unpredictable due to the different fire behavior and different fire tests.

The object of the invention was therefore to provide compounds which, on the one hand, are halogen-free and, even in small amounts, have good flameproofing properties in polymers, in particular in polymer foams.

gefunden, wobei die Reste R¹–R⁵ unabhängig von einander ausgewählt sind aus der Gruppe von C₁-C₁₆-alkyl, C₁-C₁₆-alkenyl, C₁-C₁₆-alkoxy, C₁-C₁₆-alkenyloxy, C₃-C₁₀-cycloalkyl, C₃-C₁₀-cycloalkoxy, C₆-C₁₀-aryl, C₆-C₁₀-aryloxy, C₆-C₁₀-aryl-C₁-C₁₆-alkyl, C₆-C₁₀-aryl-C₁-C₁₆-alkoxy, NR²R³, COR², COOR² und CONR²R³, und die Reste X¹ und X² unabhängig voneinander O oder S bedeuten.Accordingly, oligophosphorus compounds of the following structures Ia, IIb or IIc:

found, wherein the radicals R ¹ -R ^{5 are} independently selected from the group of C ₁ -C ₁₆ alkyl, C ₁ -C ₁₆ alkenyl, C ₁ -C ₁₆ alkoxy, C ₁ -C ₁₆ alkenyloxy , C ₃ -C ₁₀ cycloalkyl, C ₃ -C ₁₀ cycloalkoxy, C ₆ -C ₁₀ aryl, C ₆ -C ₁₀ aryloxy, C ₆ -C ₁₀ aryl C ₁ -C ₁₆ alkyl, C ₆ -C ₁₀ -aryl-C ₁ -C ₁₆ -alkoxy, NR ² R ³ , COR ² , COOR ² and CONR ² R ³ , and the radicals X ¹ and X ² independently of one another are O or S.

Preferred oligophosphorus compounds of the structure Ia, Ib and Ic are those in which the radicals R ¹ -R ^{4 are} identical and C ₁ -C ₁₆ alkenyloxy, and the radicals X ¹ , and X ^{2 are} independently of one another O or S.

Particularly preferred is 1,1,3,3-tetraallyloxy-2-phenyltriphosphine-1,3-dioxide, which can be used as a monomer in polymerization reactions due to the allylic double bonds and thus represents a reactive flame retardant.

Another object of the invention is a process for the preparation of 1,1,3,3-tetraallyloxy-2-phenyltriphosphine-1,3-dioxide, in which triallyl phosphite is reacted with dichlorophenylphosphine.

The reaction can be carried out in the presence of solvents. Preferred solvents are aromatic solvents selected from the group of toluene, xylene and mesitylene. The reaction is preferably carried out at temperatures in the range from 0 to 150 ° C., more preferably in the range from 20 to 120 ° C., very particularly preferably in the range from 20 to 30 ° C. The solvent is removed after completion of the reaction. The solvent can be removed by methods known to those skilled in the art. Preference is given to distilling. The product obtained is then dried. Preferably, the drying in a vacuum in the range of 300 to 3 mbar.

The oligophosphorus compound according to the invention can be used as a flame retardant in various plastics by the product according to the invention is bound by copolymerization to the polymeric backbone or mixed by compounding to the plastic.

The oligophosphorus compound is particularly suitable as a flame retardant in foamed and unfoamed polymers.

Examples:

Ansatz: 44,7 g 0,25 mol Dichlorphenylphosphin 101,1 g 0,5 mol Triallylphosphit 100 ml Acetonitril This compound was synthesized as follows:

Approach: 44.7 g 0.25 mol dichlorophenylphosphine 101.1 g 0.5 mol triallylphosphite 100 ml acetonitrile

Experimental procedure:

Dichlorphenylphosphine and acetonitrile in the flask while stirring. Within 52 min at 22-36 ° C, the triallyl phosphite was added dropwise. Heated to about 68 ° C and stirred for 1.5 h. 31P-NMR from the reaction solution shows almost complete conversion. The next day for a further 4 h at about 68 ° C (gentle reflux) stirred. Concentrated on a rotary evaporator. Then dried at 80 ° C and 0.1 mbar oil pump vacuum for 4 h. Crude yield: 92.54 g (86%), purity (NMR): 60%
³¹ P-NMR (toluene _d8 ), [ppm]: 28.9 (d, ¹ J _{P, P} = 5 Hz), -59.9 (t, ¹ J _{P, P} = 164 Hz).

Production of a flame-retardant foam film

10 g of polystyrene PS 158 K from BASF SE were mixed with 0.5, 0.75 and 0.1 g of 1,1,3,3-tetraallyloxy-2-phenyltriphosphine-1,3-dioxide in 35 g of methylene chloride and 1.66 g pentane dissolved. The solution was poured into an aluminum dish. After about 4 to 5 hours, the film was removed from the shell and foamed in the noise box for 1-2 minutes. The resulting foam sheet was tempered for 24 h in a drying oven at 70 ° C.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US 4111899 [0005]

Claims (6)

Oligophosphorverbindung one of the structures Ia, Ib or Ic

wherein the radicals R ¹ -R ^{5 are} independently selected from the group of C ₁ -C ₁₆ alkyl, C ₁ -C ₁₆ alkenyl, C ₁ -C ₁₆ alkoxy, C ₁ -C ₁₆ alkenyloxy, C C ₃ -C ₁₀ -cycloalkyl, C ₃ -C ₁₀ -cycloalkoxy, C ₆ -C ₁₀ -aryl, C ₆ -C ₁₀ -aryloxy, C ₆ -C ₁₀ -aryl-C ₁ -C ₁₆ -alkyl, C ₆ - C ₁₀ -aryl-C ₁ -C ₁₆ alkoxy, NR ² R ³ , COR ² , COOR ² and CONR ² R ³ , and the radicals X ¹ and X ² independently of one another are O or S. Oligophosphorverbindung the structure Ia or Ib, characterized in that the radicals R ¹ -R ^{4 are} identical and C ₁ -C ₁₆ alkenyloxy, and the radicals X ¹ , and X ^{2 are} independently O or S. 1,1,3,3-Tetraallyloxy-2-phenyltriphosphin-1,3-dioxide. Process for the preparation of 1,1,3,3-tetraallyloxy-2-phenyltriphosphine-1,3-dioxide, characterized in that triallyl phosphite is reacted with dichlorophenylphosphine. A method according to claim 4, characterized in that the reaction takes place at temperatures in the range of 0 to 150 ° C. Use of the oligophosphorus compound according to any one of claims 1 to 3 as a flame retardant in foamed and unfoamed polymers.