MATERIALS | FLAME RETARDANTS
such as Euroclass E, Bfl or UL-94 V-O at 4mm thickness (based on a loading of 20%).
Mineral opportunities Boron-based multifunctional fire retardants can function as flame retardants, smoke suppressants, afterglow suppressants and anti-tracking/anti-arc- ing agents. Borates function as flame retardants predominately in the condensed phase, with their performance able to be enhanced with the use of various co-additives. Used alone they can function as flame retardants in char-forming polymers such as polyethersulphone and polyimide. According to Kelvin Shen, a consultant for US
Borax, hexagonal boron nitride (h-BN) will play an increasingly important role in thermal management and flame retardancy in electrical and electronic applications. Commonly referred to as “white graphite” due to a plate-like hexagonal structure similar to graphite, it has been found to be a good flame retardant for many polymer systems. H-BN is an electrically insulating and highly heat conductive additive having high anisotropic thermal conductivity properties that are desired for many applications. It is stable in inert or reducing
atmospheres to about 2,700°C and in oxidising atmospheres to 850°C. Graphite itself has potential for use as a flame
retardant — expandable graphite forms a volumi- nous, thermally stable barrier residue in a fire. German company Luh is continuing research with the Institute of Polymer Technology of University Erlangen-Nuremberg aimed at providing the best possible flame-retardant effect at the lowest possible input quantity using its GHL PX 95 HT 270 product. The work is aimed at use in polyamides in particular and the company says low heat release with very low smoke production at filling rates as low as 15wt% is possible. A synergistic flame retardant system based on expandable graphite, aluminium phosphinate and melamine polyphos- phate has also been developed. With the current instability in polymer prices and availability, Europiren says it has devoted resourc- es to supporting its wire and cable clients in overcoming problems by optimising formulations and developing alternatives based on available raw materials. “Although EVA is an important compo- nent in HFFR cable formulations, it appeared possible to minimise its amount or even exclude it
CLICK HERE TO REGISTER
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74
