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EP-3580271-B1 - FLAME RETARDANT-STABILIZER COMBINATION FOR THERMOPLASTIC POLYMERS

EP3580271B1EP 3580271 B1EP3580271 B1EP 3580271B1EP-3580271-B1

Inventors

  • BAUER, HARALD
  • HÖROLD, Sebastian
  • SICKEN, MARTIN

Dates

Publication Date
20260506
Application Date
20170906

Claims (18)

  1. Use of a component C selected from the group of a metal oxide, a basic or amphoteric oxide, a metal hydroxide, a silicate, a zeolithe, a silicic acid, a glas-, glas-ceramic- or ceramic-powder, magnesium carbonate, magnesium-calcium-carbonate (Dolomite); zinc stannate, zinc hydroxyl stannate, zinc phosphate, zinc sulfide, zinc borate or aluminium phosphate to prepare a flame retardant-stabilizer combination for thermoplastic polymers, comprising, as component A, from 25 to 99.9% by weight of a phosphinic acid salt of the formula (I) wherein R 1 , R 2 are the same or different and are each C 1 -C 18 -alkyl, linear or branched, C 6 -C 18 -aryl, C 7 -C 18 -arylalkyl or C 7 -C 18 -alkylaryl, or R 1 and R 2 form one or more rings with each other, M is Mg, Ca, Al, Sb, Sn, Ge, Ti, Zn, Fe, Zr, Ce, Bi, Sr, Mn, Li, Na, K and/or a protonated nitrogen base; m is from 1 to 4; as component B, from 0 to 75 % by weight of a synergist or of a phosphorus/nitrogen flame retardant and, from 0.1 to 50 % by weight of said component C, the sum of the components always being 100 % by weight, wherein the angle of repose of said flame retardant-stabilizer combination is between 5° and 45° as measured by continuously pouring a powder sample through a dropping down to a round plate with a radius of r, accumulating the powder into a cone-shaped pile growing up until the height of the pile did not increase, measuring the height of the pile, h and calculating the angle of repose, α, was according to formula tg α = h/r, and wherein the angle of repose of the flame retardant-stabilizer combination comprising component C) has a decreased numeric value compared to the angle of repose of a flame retardant-stabilizer combination comprising the same components A and B but without component C).
  2. Use as claimed in claim 1, wherein the angle of repose of said flame retardant-stabilizer combination is between 20° and 40°.
  3. Use as claimed in claim 1 or 2, wherein R 1 , R 2 are the same or different and are each methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, n-pentyl, 2-pentyl, 3-pentyl, 2-methylbutyl, 3-methylbutyl (iso-mentyl), 3-methylbut-2-yl, 2-methylbut-2-yl, 2,2-dimethylpropyl (neopentyl), hexyl, heptyl, octyl, nonyl, decyl, cyclopentyl, cyclopentylethyl, cyclohexyl, cyclohexylethyl, phenyl, phenylethyl, methylphenyl und/oder methylphenylethyl
  4. Use as claimed in one or more of claims 1 to 3, wherein M is a calcium, aluminum, zinc, titanium or iron ion.
  5. Use as claimed in one or more of claims 1 to 4, wherein component B comprises one or more of groups a) - e) a) condensation products of melamine, b) reaction products of melamine with polyphosphoric acid and/or reaction products of condensation products of melamine with polyphosphoric acid or mixtures thereof, c) phosphates of the formulae (NH 4 ) y H 3-y PO 4 or (NH 4 PO 3 ) z , where y is from 1 to 3 and z is from 1 to 10 000, d) N-synergists of the formulae (III) to (VIII) or mixtures thereof. where R 5 to R 7 are each hydrogen, C 1 -C 8 -alkyl, C 5 -C 16 -cycloalkyl or -alkylcycloalkyl, possibly substituted by a hydroxyl or a C 1 -C 4 -hydroxyalkyl function, C 2 -C 8 -alkenyl, C 1 -C 8 -alkoxy, -acyl, -acyloxy, C 6 -C 12 -aryl or -arylalkyl, -OR 8 and -N(R 8 )R 9 , N-alicyclic or N-aromatic, R 8 is hydrogen, C 1 -C 8 -alkyl, C 5 -C 16 -cycloalkyl or -alkylcycloalkyl, possibly substituted by a hydroxyl or a C 1 -C 4 -hydroxyalkyl function, C 2 -C 8 -alkenyl, C 1 -C 8 -alkoxy, -acyl, -acyloxy or C 6 -C 12 -aryl or -arylalkyl, R 9 to R 13 are each the same groups as R 8 and also -O-R 8 , m and n are each independently of 1, 2, 3 or 4, X is an acid which can form adducts with triazine compounds (III); or oligomeric esters of tris(hydroxyethyl) isocyanurate with aromatic polycarboxylic acids, e) aluminium phosphites.
  6. Use as claimed in claim 5, wherein the condensation products a) of melamine are melem, melam, melon and/or more highly condensed compounds thereof; the reaction products of melamine b) are dimelamine pyrophosphate, melamine polyphosphate, melem polyphosphate, melam polyphosphate, melon polyphosphate and/or mixed polysalts of this type; the phosphates c) are ammonium hydrogenphosphate, ammonium dihydrogenphosphate and/or ammonium polyphosphate; the N-synergists d) are benzoguanamine, tris(hydroxyethyl) isocyanurate, allantoin, glycouril, melamine, melamine cyanurate, dicyandiamide and/or guanidine; the aluminium phosphites e) are of the formula (IX), (II) and/or (X) Al 2 (HPO 3 ) 3 x (H 2 O) q (IX) where q is 0 to 4 Al 2,00 M z (HPO 3 ) y (OH) v x (H 2 O) w (II) where M are Alkali metal ions z 0,01 to 1,5 y 2,63 to 3,5 v 0 to 2 and w 0 to 4, Al 2,00 (HPO 3 ) u (H 2 PO 3 ) t x (H 2 O) s (X) where u is 2 to 2,99 t 2 to 0,01 and s 0 to 4 and/or mixtures of aluminium phosphite of formula (IX) with aluminium salt of limited solubility and nitrogen free ions, mixtures of aluminium phosphite of formula (X) with aluminium salts, aluminium phosphite [Al(H2PO 3 ) 3 ], secondary aluminium phosphite [Al 2 (HPO 3 ) 3 ], basic aluminium phosphite [Al(OH)(H 2 PO 3 ) 2 *2aq], aluminium phosphite tetrahydrate [Al 2 (HPO 3 ) 3 *4aq], aluminium phosphonate, Al 7 (HPO 3 ) 9 (OH) 6 (1,6-hexandiamine) 1,5 *12H 2 O, Al 2 (HPO 3 ) 3 *xAl 2 O 3 *nH 2 O with x = 2,27 - 1, Al 4 H 6 P 16 O 18 and/or mixtures of 0 - 99,9 wt.-% Al 2 (HPO 3 ) 3 *nH 2 O with 0,1 - 100 Gew.-% sodium aluminium phosphite.
  7. Use as claimed in one or more of claims 5 to 6, wherein the aluminium phosphite is a mixture of 50 - 99 wt.-% Al 2 (HPO 3 ) 3 x (H 2 O) q where q is 0 to 4 with 1 - 50 wt.-% sodium aluminium phosphite.
  8. Use as claimed in one or more of claims 5 to 6, wherein the aluminium phosphite is a mixture of 50 - 99 wt.-% Al 2 (HPO 3 ) 3 x (H 2 O) q where q is 0 to 4 with 1 - 50 wt.-% Al 2,00 M z (HPO 3 ) y (OH) v x (H 2 O) w (II) where M is sodium, z is 0,005 to 0,15, y is 2,8 to 3,1, v is 0 to 0,4 and w is 0 to 4.
  9. Use as claimed in one or more claims 1 to 6, wherein component B is melamine polyphosphate.
  10. Use as claimed in one or more of claims 1 to 9, wherein component C is selected from magnesium oxide, zinc oxide, manganese oxide, tin oxide, magnesium hydroxide, hydrotalcite, hydrocalumite, dihydrotalcite, calcium hydroxide, zinc hydroxide, tin oxide hydrate, manganese hydroxide, magnesium carbonate magnesium-calcium-carbonate (Dolomite); zinc stannate, zinc hydroxyl stannate, zinc phosphate, zinc sulfide, aluminium oxide, aluminium hydroxide, Boehmite, aluminium sulfate hydroxide, aluminium phosphate, calcium oxide, basic zinc silicate or zinc borate.
  11. Use as claimed in claim 1, wherein component C is selected from calcium oxide, manganese oxide, tin oxide, tin oxide hydrate, manganese hydroxide, basic zinc silicate, zinc borate, zinc stannate, magnesium hydroxide, zinc oxide, dihydrotalcite or Boehmite
  12. Use as claimed in claim 1, wherein component C is selected from magnesium oxide, zinc oxide, manganese oxide, tin oxide, dihydrotalcite, hydrocalumite, magnesium hydroxide, calcium hydroxide, zinc hydroxide, tin oxide hydrate, manganese hydroxide, zinc borate, basic zinc silicate, zinc stannate or mixtures of these substances, the sum of the components always being 100 % by weight.
  13. Use as claimed in one or more of claims 1 to 12, wherein from 50 to 99 % by weight of component A, from 0 to 50 % by weight of component B and from 1 to 20 % by weight of component C are present.
  14. Use as claimed in one or more of claims 1 to 13, wherein from 50 to 78 % by weight of component A, from 20 to 50 % by weight of component B and from 2 to 20 % by weight of component C are present.
  15. Use as claimed in one or more of claims 1 to 14, wherein from 60 to 98 % by weight of component A and from 2 to 40 % by weight of component C are present.
  16. A flame retardant-stabilizer combination as claimed in one or more of claims 1 to 15, characterised in that the residual moisture content of said flame retardant-stabilizer combination is between 0.01 wt.-% and 10 wt.-%, and preferably between 0.1 wt.-% and 1 wt.-%.
  17. A flame retardant-stabilizer combination as claimed in one or more of claims 1 to 16, characterised in that the bulk density of said flame retardant-stabilizer combination is between 100 g/L and 1000 g/L.
  18. A flame retardant-stabilizer combination as claimed in one or more of claims 1 to 17, characterised in that the tap density of said flame retardant-stabilizer combination is between 200 g/L and 1200 g/L.

Description

The present invention relates to a flame retardant-stabilizer combination for thermoplastic polymers with good flowability and to flame retardant polymeric molding compositions which comprise such flame retardant-stabilizer combinations. The present invention belongs to the technical field of flame retardants, and more particularly flame retardant-stabilizer combination having a good fluidity. For thermoplastic polymers in particular, salts of phosphinic acids (phosphinates) have been found to be effective flame-retardant additives (DE-A-2 252 258 and DE-A-2 447 727). Moreover, synergistic combinations have been found of phosphinates with certain nitrogen compounds and are more effective as flame retardants in a whole series of polymers than the phosphinates alone (PCT/EP97/01664 and also DE-A-197 34 437 and DE-A-197 37 727). DE-A-196 14 424 describes phosphinates in combination with synergists in polyesters and polyamides. DE-A-199 33 901 describes phosphinates in combination with melamine polyphosphate as a flame retardant for polyesters and polyamides. WO-A-2004022640 describes flame retardant combinations for thermoplastics, said flame retardant combinations, in addition to flame retardancy, exerting a stabilizing action on the plastic. The shortcomings of the above described methods are that if flowability of dialkylphosphinic salt is poor, uneven distribution of the flame retardant polymeric molding compositions may occur which can have negative consequences on the flame retardant properties of the flame retardant polymeric molding compositions. CN-A-104059101A describes the advantageous effect of adding process aids to the production of dialkylphosphinic acid salts on the flowability, namely the angle of repose. The shortcoming of this method is that the addition of process aids to the production can have wide spread negative consequences on other product properties, adds a lot of more complexity to the production process and can even contribute security hazards. US 2006/089435 A1 discloses a flameproof agent-stabilizer-combination for thermoplastic polymers comprising phosphinic acid salt or diphosphinic acid salt as component A, optionally a nitrogen-containing synergist or a P/N-flame-retardant as component B and selected oxides, hydroxides or other compounds as component C. US 2006/084734 A1 discloses dialkylphospinic acid salts, their use and their manufacture. From US 2008/161490 A1 halogen-free flame retardants are known which can be used for manufacturing polyamide molding compositions with increased glow-wire resistance. US 2014/066551 A1 discloses glass-filled polyamide compositions and articles made therefrom. From US 2004/227130 A1 flame-retardant and stabilizer combinations for thermoplastic polymers are known. These documents do not disclose the use of a component, such as an oxide or hydroxide for making flame-retardants having an angle of repose with a decreased numeric value compared to the angle of repose of a flame retardant-stabilizer combination comprising no such component. Surprisingly, it was found that addition of a small amount of additives can have advantageous effects on the flowability of the flame retardant without the need to change the whole production process. Furthermore the possibility to use the additive in different amounts offers great flexibility in choosing the desired flowability. It is therefore an object of the present invention to provide flame retardant combinations for thermoplastics, said flame retardant combinations, in addition to flame retardancy, exerting high flowability. This object is achieved by the addition of basic or amphoteric metal oxides, metal hydroxides, carbonates, silicates, borates, stannates, mixed oxide hydroxides, oxide hydroxide carbonates, hydroxide silicates or hydroxide borates or mixtures of these substances, coupled with the use of phosphinates or their mixtures with synergists as flame retardants. The obtained flame retardant-stabilizer combination of the present invention is prepared by adding a component C and has a high flowability, and the angle of repose is up to 5° - 45°, so that it can fundamentally solve the problems of poor flowability and uneven distribution of flame retardants in resins. The invention therefore provides the use of a component C) defined below to prepare a flame retardant-stabilizer combination for thermoplastic polymers, said flame retardant-stabilizer combination comprising, as component A, from 25 to 99.9 % by weight of a phosphinic acid salt of the formula (I) wherein R1, R2are the same or different and are each C1-C18-alkyl, linear or branched, C6-C18-aryl, C7-C18-arylalkyl or C7-C18-alkylaryl, or R1 and R2 form one or more rings with each other,Mis Mg, Ca, Al, Sb, Sn, Ge, Ti, Zn, Fe, Zr, Ce, Bi, Sr, Mn, Li, Na, K and/or a protonated nitrogen base;mis from 1 to 4; as component B, from 0 to 75 % by weight of a synergist or of a phosphorus/nitrogen flame retardant and,from 0.1 to 50 % by weight