FLAME RETARDANT COMPOSITION

Abstract

The invention provides aflame retardant composition comprising and ammonium polyphosphate a silane functionalised ethylene copolymer.

Claims

1. A flame retardant composition comprising: a) an ammonium polyphosphate; and b) a silane functionalised ethylene copolymer.

2. The flame retardant composition according to claim 1, wherein a weight ratio of the ammonium polyphosphate to the silane functionalised ethylene copolymer is in the range 9:1 to 1:9.

3. The flame retardant composition according to claim 1, wherein the silane functionalised ethylene copolymer is a polymer of ethylene (a) selected from: (a1) a copolymer of ethylene and a silane group(s) containing comonomer; (a2) a copolymer of ethylene with one or more polar comonomer(s) selected from (C1-C6)-alkyl acrylate or (C1-C6)-alkyl (C1-C6)-alkylacrylate comonomer(s), wherein copolymer (a2) bears silane group(s) containing units and wherein copolymer (a2) is different from the polymer of ethylene (a1); or (a3) a copolymer of ethylene with one or more (C3-C10)-alpha-olefin comonomers, which is different from the polymer of ethylene (a1) and the polymer of ethylene (a2) and to which silane group(s) containing units have been grafted.

4. The flame retardant composition according to claim 3, wherein the silane grafted ethylene copolymer is a copolymer of ethylene and at least one polar comonomer(s) selected from (C1-C6)-alkyl acrylates or (C1-C6)-alkyl (C1-C6)-alkylacrylates.

5. The flame retardant composition according to claim 1, wherein the silane functionalised ethylene copolymer is a copolymer of ethylene and a silane containing comonomer and optionally one or more further comonomers.

6. The flame retardant composition according to claim 5, wherein the silane functionalised ethylene copolymer is a terpolymer.

7. The flame retardant composition according to claim 1, wherein the silane functionalised ethylene copolymer comprises a silane group(s) containing unit or a silane group(s) containing comonomer of Formula (I):
R1SiR2qY3-q  (I) wherein R1 is an ethylenically unsaturated hydrocarbyl, hydrocarbyloxy or (meth)acryloxy hydrocarbyl group, each R2 is independently an aliphatic saturated hydrocarbyl group, Y is the same or different, and is a hydrolysable organic group and wherein q is 0, 1 or 2.

8. The flame retardant composition according to claim 1, wherein said silane functionlaised ethylene copolymer is a copolymer of ethylene with a methyl acrylate comonomer and a vinyl trimethoxysilane comonomer.

9. (canceled)

10. A polymer composition comprising at least one polymer and the flame retardant composition of claim 1.

11. A process for coating a substrate with the flame retardant composition of claim 1, said process comprising applying said composition to the surface of said substrate.

12. A substrate comprising a fabric substrate, coated with the flame retardant composition of claim 1.

13. The substrate as claimed in claim 12, wherein the fabric substrate is a woven or non-woven fabric.

14. An article comprising at least one component formed from the coated substrate as defined in claim 12.

15. The article as claimed in claim 14, wherein the article is selected from the group consisting of office furniture, vehicle interiors, seat cushions, back rest cushions, pillows, upholstered furniture, bed mattresses, wall coverings, shoes, sports bags, inlay of sky boots, sports equipment, carpets, rubber boats, PVC swimming pools, life vests, handbags, purses, table coverings, table mats, stationary, saddlebags, tool bags.

16. The substrate as claimed in claim 13, wherein the fabric substrate is a knitted fabric.

17. The article as claimed in claim 15, wherein the shoes comprise tongue, vamp, heel counter, quarter, or a combination thereof.

18. The article as claimed in claim 15, wherein the sports equipment comprises boxing gloves, boxing balls, or a combination thereof.

19. The article as claimed in claim 15, wherein the stationary comprises books, wood inlay, or any combination thereof.

Description

[0131] The invention will now be described with reference to the following non limiting figures and examples.

[0132] FIG. 1: Calendaring coating roller equipment

TEST METHODS

Density

[0133] Density of the materials is measured according to ISO 1183-1:2012, with isopropanol-water as gradient liquid. The cooling rate of the plaques when crystallising the samples was 15° C./min. Conditioning time was 16 hours.

Melt Flow Rate (MFR) or Melt Index (MI)

[0134] The melt flow rate (MFR) is determined according to ISO 1133 and is indicated in g/10 min. The MFR is an indication of the melt viscosity of the polymer. The MFR is determined at 190° C. for PE and at 230° C. for PP. The load under which the melt flow rate is determined is usually indicated as a subscript, for instance MFR.sub.2 is measured under 2.16 kg load, MFR.sub.5 is measured under 5 kg load or MFR.sub.21 is measured under 21.6 kg load.

Molecular Weights, Molecular Weight Distribution, Mn, Mw, MWD

[0135] The weight average molecular weight Mw and the molecular weight distribution (MWD=Mw/Mn wherein Mn is the number average molecular weight and Mw is the weight average molecular weight) is measured by a method based on ISO 16014-4:2003.

Comonomer Content

[0136] Comonomer Content (% wt and % mol) was determined by using .sup.13C-NMR. The .sup.13C-NMR spectra were recorded on Bruker 400 MHz spectrometer at 130° C. from samples dissolved in 1,2,4-trichlorobenzene/benzene-d.sub.6 (90/10 w/w). Conversion between % wt and % mol can be carried out by calculation.

Cigarette Test

[0137] An assessment of ignitability was carried out in accordance with the BS EN 1021-1:2006 smouldering cigarette test

Flame Retardancy

[0138] Flame retardant behaviour was assessed using an FTT Dual Cone calorimeter R1771 according to ISO 5660:2015.

EXPERIMENTAL

Materials

[0139] Propylene based plastomer (PP plast): a random propylene ethylene metallocene plastomer, density=0.862 g/cm.sup.3, MFR.sub.2 (230° C., 2.16 kg)=20 g/10 min

[0140] Ethylene based plastomer (1) (PE plast 1): an ethylene octene metallocene plastomer, density=0.870 g/cm.sup.3, MFR.sub.2 (190° C./2.16 kg)=6.6 g/10 min

[0141] Ethylene based plastomer (2) (PE plast 2): an ethylene octene metallocene plastomer, density=0.902 g/cm.sup.3, MFR.sub.2 (190° C./2.16 kg)=10 g/10 min

[0142] Ethylene based plastomer (3) (PE plast 3): an ethylene octene metallocene plastomer, density=0.902 g/cm.sup.3, MFR.sub.2 (190° C./2.16 kg)=3 g/10 min

[0143] High MFR PP plastomer (1): a random propylene ethylene metallocene plastomer, density=0.879 g/cm.sup.3, MFR.sub.2 (230° C., 2.16 kg)=7715 g/10 min

[0144] Polypropylene copolymer (PP copo): a propylene ethylene random heterophasic copolymer, density=890 g/cm.sup.3, MFR.sub.2 (230° C., 2.16 kg)=3.8 g/10 min

[0145] Flame retardant 1 (FR1): ammonium polyphosphate (commercially available ADKSTAB FP2500S)

[0146] Flame retardant 2 (FR2): copolymer of ethylene, methyl acrylate and vinyl trimethoxy silane (VTMS), density=0.946 g/cm.sup.3, MFR.sub.2 (190° C./2.16 kg)=3 g/10 min

[0147] Flame retardant 3 (FR3): ammonium polyphosphate (commercially available IC FR5110)

Preparation of Compostions:

[0148] Sixteen inventive compositions were prepared by gravitmetric feeding of various components to a twin screw extruder.

TABLE-US-00001 TABLE 1 Production Data for Inventive Compositions (amounts are given in parts by weight) High PE PE PE MFR Anti- PP Plast Plast Plast PP PP Proc. Emulsifier UV static Plast 1 2 3 plast copo FR1 FR2 FR3 Additive (GMS) additive additive Pigment IE1 30 43 — — 3 — 10 12 8 3 2 — 3 IE2 30 43 — — 3 — 10 12 6 3 2 3 3 IE3 30 43 — — 3 — 10 12 6 3 2 4 3 IE4 30 43 — — 3 — 10 12 6 3 2 6 3 IE5 30 43 — — 3 — 10 12 6 3 2 10 3 IE6 30 43 — 6 1 — 10 12 8 3 2 — 3 IE7 30 43 — — 1 — 10 6 8 3 2 3 3 IE8 30 43 — — 1 — 10 — 8 3 2 3 3 IE9 30 43 — — 1 — 10 12 8 3 2 3 3 IE10 30 43 — — 1 — 10 18 8 3 2 3 3 IE11 30 43 — — 1 — 15 24 8 3 2 3 3 IE12 30 43 — — 1 — 10 12 8 3 2 3 3 IE13 30 43 — — 1 — 10 12 — 3 2 — 3 IE14 31 41 — — 1 10.3 — 5.2 6.2 — — 2.1 — 3.1 IE15 28.9 38.9 — — 1 9.7 — 4.9 11.7 — — 2 — 2.9 IE16 26.9 35.9 — — 0.9 9 — 6.7 16.1 — — 1.8 — 2.7

Production of Coated Substrates & Cigarette Test Results:

[0149] Five additional inventive compositions (IE17 to IE21) were prepared in the same manner as for IE1 to IE16 and were coated onto fabric substrates using the following methods. Lab-scale calendaring coating equipment (FIG. 1) was employed, consisting of two heated rollers, onto which the raw material or compounded polymer was placed, in the form of pellets. The rollers mix the polymer until a homogeneous blend is achieved, then the front roller transfers the melted coating onto the backer fabric at a set thickness (total thickness of the backer and coating together), and a surface texture is applied with a water-cooled embossing roller before the fabric is re-wound onto a roll. Dry blends (the separate components—not compounded) do not mix sufficiently to make a homogeneous coating. Therefore, these blends were first compounded using a twin-screw extruder and, where possible, drawn through a water bath to a pelletiser to make compound pellets. These pellets were then applied to the heated rollers for coating. The more flexible blends were too soft to cut into pellets. For these coatings, the compound was extruded straight onto a metal spatula and then transferred to the rollers.

[0150] A polyurethane lacquer was further added and the materials subjected to the Cigarette test. The formulations used and the results of the tests are shown in Table 2. Table 3 shows flame retardancy data for selected compositions.

TABLE-US-00002 TABLE 2 Coated substrate formulations & Cigarette test results (figures represent parts by weight) PE High Flame Flame Plastomer PP MFR PP retardant retardant UV Cig. Substrate 1 Pigment Plastomer plastomer 1 2 additive Lacquer test IE17 PP jersey 43 3 30 3 12 10 2 PU Pass White IE18 PP jersey 43 3 30 3 12 10 2 PU Pass Orange IE19 PP-FR* 43 3 30 3 2 10 2 PU Pass Blue IE20 PP jersey 43 3 30 3 18 10 2 PU Pass Blue IE21 PP-FR* 43 3 30 3 18 10 2 PU Pass Blue *Polypropylene substrate comprising flame retardant

TABLE-US-00003 TABLE 3 Flame Retardancy results (test carried out on composition only, no fabric) IE18 IE20 burning time s 138 177.5 burning time #1 s 230 305 burning time SD s 130.1 180.3 comment Char formation heat release rate kW/m2 97.56 92.6 heat release rate #1 kW/m2 97.56 92.6 heat release rate SD kW/m2 0 0 ignition time s 138 177.5 Ignition time #1 s 46 50 Ignition time #2 s ignition time SD s 130.1 180.3 Oxygen content % 19 21