New Developments in Mineral Flame Retardants

Transcription

1 1 New Developments in Mineral Flame Retardants Dr. Annika Luks Nabaltec AG Contact in China: Mr. Andy Yang Soule International (Shanghai) Co., Ltd. Room 1702, Fudan Science Park Building, No.11, Guo Tai Road, Shanghai , China Tel: address:

2 2 Overview Introduction - metal hydrates as flame retardants - working mechanism - advantages of metal hydrates as flame retardants Aluminium hydroxide (ATH) other mineral flame retardants Summary Metal hydrates as flame retardants Aluminium hydroxide (Al(OH) 3 or ATH) synthetic (Bayer-Process) Magnesium hydroxide (Mg(OH) 2 or MDH) synthetic; natural (Brucite) Aluminium monohydrate (AlO(OH) or AOH) synthetic (hydrothermal synthesis)

3 3 Working mechanism, thermal decomposition 200 C 2Al(OH) 3 Al 2 O 3 + 3H 2 O APYRAL kj/kg Mg(OH) 2 APYMAG 300 C kj/kg MgO + H 2 O 340 C 2AlOOH Al 2 O 3 + H 2 O kj/kg APYRAL AOH Working mechanism - energy consumption - formation of an oxide layer - cooling of the polymer surface - dilution of burnable gases kj/kg 3H 2 O 2Al(OH) 3 + Al 2 O 3

4 4 Working mechanism, DSC-diagrams Working mechanism, smoke suppression Fire at the TV tower in Moscow, August 2000

5 5 Advantages of mineral based flame retardants Halogen free Environmentally friendly No formation of possibly dangerous decomposition products Remarkable reduction of the smoke density Reduction of consequential damages Flexibility in the composition of the compound overview Introduction Aluminium hydroxide (ATH) - application areas for ATH - ATH for (HFFR) cable compounds - Compound properties - submicron sized APYRAL 200 SM for superior performance Other mineral flame retardants Summary

6 6 Mineral flame retardants for thermosets processes: SMC, BMC Hand-Lay-Up RTM Pultrusion products: housings switches casting cable sheathings panels viscosity significant process parameter depends on particle size reverse proportional to the particle size general recommendation: use of coarse and ground grades Viscosity depending on the filling level UP Resin Palapreg P17; Brookfield RVT, 23 C relative viscosity (-) Apyral 40CD Apyral 15 Apyral 24 Apyral 16 Apyral 33 Apyral 22 Apyral 30X Apyral 20X Filling level (phr)

7 7 Applications for fine precipitated ATH fine precipitated ATH melt compounding + extrusion Different standards are valid for different applications and in different regions. Standard cable: IEC foam: DIN 4102; B2 DIN 4102; B1 DIN 4102; B2 DIN 5510; S4 UL94 V0 DIN 4102; B1 NF ;M1 SBI, B ; S1 Minimum Filling level wt.-% wt.-% +otherfr wt.-% wt.-% wt.% 80 wt.-% One PVC cable PVC compound phrath / MDH in the jacketing compound phr ATH / MDH in the insulation compound. - hardly any mineral flame retardants in the bedding compound

8 8 Properties of a PVC cable compound PVC compound components phr (wt.-%) PVC 100 (48.7) ATH/MDH 50 (24.3) Softener 50 (24.3) Stabiliser 5 (2.43) PE-Wax 0.5 (0.24) Elongation at break 220 (%) Tensile strength 13.4 (MPa) MVR (cm³/10 min) C, 21.6 kg LOI (%) 30 Elongation at break is above 150% Tensile strength is above 10 MPa Good Processability Good flame retardancy (UL94 V0 classification) Properties of a PVC cable compound 1500 Maximum smoke density of soft PVC Optical density Ds Sb2O3 APYRAL 40 CD significant reduction of the maximum smoke density via replacement of antimony trioxide by ATH

9 9 One HFFR cable Bedding compound ca. 20% polymer: - EPDM - EVA (high VA content) - mpe (PE-co-octen) ca. 80 % filler: - chalk - ATH (ground) - MDH (brucite) Insulation compound ca. 40 % polymer: -XLPE - LDPE / MDPE / EVA / mpe ca. 60 % mineral flame retardant: - ATH (fine precipitated) - MDH (fine precipitated) important: low-electrolyte content! Jacketing compound 35-40% polymer: - LDPE / MDPE / EVA / mpe - EPDM / EVA 60-65% mineral flame retardant - ATH (fine precipitated) - MDH (fine precipitated) Properties of an HFFR cable compound PE/EVA compound components wt.-% (phr) LLDPE 9.66 EVA ATH (155.2) Vinyl silane 0.80 (2.07) Processing aid 0.30 (0.78) Stabiliser 0.20 (0.52) Peroxide 0.04 (0.10) Good Elongation at Break Acceptable Tensile Strength ( > 10 MPa ) Good Processability Break 248 (%) Tensile Strength 10.9 (MPa) MVR (cm³/10 min) C, 21.6 kg LOI (%) 36.6 Good Flame Retardancy (UL94 V0 classification)

10 10 Submicron sized ATH To further improve the fire resistance of an HFFR cable compound you have several possibilities, e.g. 1: increase the content of ATH 2: increase the surface area of the ATH 3: combine standard ATH types with submicron sized synergists Flame Retardancy of EVA Compounds, filled with ATH 40, different filling levels 1: increase the content of ATH ATH 40 (APYRAL 40CD) in EVA19 (19% VA) as model HFFR 34.6%-39.6% EVA19 0.4% AS ATH 40 60wt.-% ATH 40 63wt.-% ATH 40 65wt.-% LOI in %O UL94-V (3.2mm) n.c. n.c V1 E@B in % MVR in cm 3 /10min at 190 C/21.6kg Increase in filling level leads to higher LOI and UL 94 V rating but lower E@B and MVR You are limited in increasing the FR of your compound this way!

11 11 Eigenschaften Flame Retardancy einer of HFFR-Kabel-Mischung EVA Compounds 61.3 wt.-% ATH (%) : increase the surface area of the ATH BET (m²/g) TS (MPa) LOI (%O 2 ) BET (m²/g) MVR (cm³ / 10 min) Increase in BET leads to higher TS but lower E@B Increase in BET leads to higher LOI but lower MVR (lower output) Submicron sized ATH 3: combine standard ATH types with synergists 29% EVA28 5.6% EVA60 0.4% AS TS (MPa) E@B (%) MVR (cm³/10 min) 190 C/21,6 kg LOI (%O 2 ) UL94- V at 1.6mm UL94-V at 1.6mm afterburn 65% APYRAL 40CD 6, ,7 40 V % APYRAL 40CD 9, ,6 44 V % APYRAL 120E Fire resistance still too low! V0 is necessary!

12 12 Wirkprinzip, Preparation of thermische Submicron Zerfallsreaktionen fillers Micron D50 = 1300 nm BET = 3.5 m 2 /g Precipitation Submicron ATH D50 = 400 nm Platelet thickness 30 nm BET = 20 m 2 /g Precipitation Wirkprinzip, Compoundingthermische Zerfallsreaktionen Filler blend comparable to APYRAL 60CD Maximum Temperature Torque Filler T [ C] M [Nm] APYRAL 40CD APYRAL 60CD APYRAL 120E APYRAL 40CD APYRAL 200 SM

13 13 Compound Properties 29% EVA28 5.6% EVA60 0.4% AS TS (MPa) (%) LOI (%O 2 ) UL94-V at 1.6mm UL94-V at 1.6mm afterburn 65% APYRAL 40CD 6, V % APYRAL 40CD 9, V % APYRAL 120E 50% APYRAL 40CD +15% APYRAL 200 SM 9, V-0 18 Combinations with ATH of higher BET offer good fire retardancy values and MVR additionally offer a good balance of mechanical data overview Introduction Aluminium hydroxide (ATH) Other mineral flame retardants - Magnesium hydroxide (MDH) - Aluminium oxide hydroxide / Boehmite (AOH) Summary

14 14 Magnesium hydroxide MDH precipitated and natural MDH types make around 10 % of the market share of ATH precipitated MDH-Types are used in PP, PA, special compounds use in PE/EVA (higher extrusion speed) is no longer necessary (high MVR compounds can be produced with ATH!) MDH use in thermosets neither necessary nor easy MDH has an influence on the hardening of the resin Magnesium hydroxide MDH Synthetic types cable application (coated grades in PP) other E&E applications (PA, PP) Natural types HFFR cables (filling compounds; with restrictions jacketing compounds) PVC compounds (USA) Bitumen roofings (USA, Scandinavia) EPDM, TPO roofings (USA)

15 15 Boehmite AOH APYRAL AOH 60 fine particles (800 nm) low abrasion (Mohs = 3) low electrolyte content high temperature stability (up to 340 C) compatible with epoxy resins high-t g -Laminates can be produced easy to screw recommended for Pb free soldering gooddispersioninresins until now no Stand-Alone solution Boehmite, a versatile synergist Boehmite offers extraordinary good processability and mechanical data in compounds. The fire resistance is often not good enough when it is used as the only flame retardant. But the combination with another flame retardant often results in synergistic effects.

16 16 Boehmite, a versatile synergist APYRAL AOH, a synthetic MDH and APYMAG AOH, an optimised blend of MDH and AOH, in EVA (filling level 61.3 wt.-%), mechanical data, melt volume rate and LOI in comparison. filler BET [m²/g] E@B [%] TS [MPa] MVR [cm 3 /10 min] 190 C, 21.6 kg LOI [%O 2 ] APYRAL AOH ,7 28 MDH ,7 42 APYMAG AOH ,0 38 Boehmite, a versatile synergist UL 94V-rating of 8-layered PCB-laminates, based on a DGEBA resin. Flame retardant is a metal phosphinate and APYRAL AOH 30. (DOW DER TM 663UE, DEH TM 81, E-Glass Hexcel 7628) Laminate thickness / mm APYRAL AOH 30 / wt.-% Metal phosphinate / wt.-% 1, V1 1, V1 2, V0 2, V0 UL 94Vrating

17 17 Boehmite, a versatile synergist If the content of boehmite in a filler mix (with ATH or MDH) is at an optimum, the LOI of compounds containing 61.3 wt-% of the mineral flame retardant is even higher than with the better flame retardant ATH or MDH alone a synergy. EVA with 65 wt.-% APYRAL 40CD EVA with 56 wt.-% APYRAL 40CD and 9 wt.-% APYRAL AOH 180E Boehmite, submicron sized synergist ACTILOX 400 SM Submicron AOH D50 = 300 nm BET = 40 m 2 /g

18 18 Boehmite, submicron sized synergist LOI and UL 94-V at 3.2 mm for EVA (19% VA content) filled with APYRAL 40CD and ACTILOX 400 SM at different ratios (60 / 0 = 60 wt.-% APYRAL 40CD) ACTILOX 400 SM at same loading LOI is boosted by 4-5 %O 2 UL94-V0 (3.2 mm) classification at only 58 wt.-% total load overview Introduction Aluminium hydroxide (ATH) Other mineral flame retardants Summary

19 19 Summary ATH clearly dominates the market for mineral flame retardants MDH and Boehmite have good future prospects developments in HFFR cable compounds are cost and innovation driven reduction of process costs (compounding, extrusion) specialities become more and more important, new standards for transportation (EN 45545) and building industry (CPD) new developments in oil and gas production or energy production in off shore wind parks require sea water resistant high flexible HFFR cables new developments in engineering plastics lead to higher demand in new FR solutions because of the high process temperatures and the necessary chemical resistance of the material Wirkprinzip, Summary thermische Zerfallsreaktionen Submicron metal hydrates made of ATH and AOH Are an option to boost fire performance of compounds based on standard metal hydrates Give very good balanced tensile-elongation properties Offer very good compounding properties, especially when combined with CD-Technology Allow a total filler load reduction,......but...a minimum BET surface/fineness is required and the ratio of standard ATH/submicron is important

20 20 Summary ATH clearly dominates the market for mineral flame retardants MDH and Boehmite have good future prospects development in thermoset driven by A) new standards (building, transport) higher filling levels viscosity optimised ATH grades B) replacement of halogenated FR in E&E because of RoHS & WEEE boehmite is an option for high process temperatures in PCB production (lead free soldering) boehmite is an option for halogen free FR synergies in engineering plastics Thanks to the organisers, all colleagues from Nabaltec. Thank You!