MATERIALS | WIRE AND CABLE
micromodules during installation. The company says the flame-retarded polyolefin
formulations are halogen-free and offer low smoke and fume generation rates. In addition, Avient says fumes released on burning are less corrosive than those associated with PA and PBT, which means surrounding structures not directly affected by any potential fire are less likely to suffer damage. With processing speeds of up to 1,000 m/min and a lower melting point than PBT, the new grades are claimed to provide opportunity for faster processing and can also contribute to reduced energy use during manufacturing. The company says the grades also offer potential to reduce wall thickness.
Flexible jacketing Other recent additions to the Avient range for fibre optic cables include Eccoh 5565 and Eccoh 5978 UV, both halogen-free flame retardant grades intended for jacketing applications. Eccoh 5565 is said to offer good flexibility and environmental stress cracking resistance (ESCR), withstanding up to 20,000 flex fatigue cycles. It is capable of performing over a temperature range from -40 to +80°C, making it suitable for use in dry optical fibre cable applications or where improved resistance to low temperatures is required, such as indoor and outdoor duct cables, power-to-antennas, or hybrid cables for 5G networks. Eccoh 5978 UV formulations offer flame retar- dancy up to EU Construction Products Regulation (CPR) class B2ca,s1,a1,d, together with good char forming, UV resistance and ESCR. The company says this makes them an appropriate choice for aerial drop cables, which are often under continu- ous stress from the clamps that hold them in place. Demand for halogen-free flame retardant (HFFR) cable is on the increase as changes in regulations increasingly preclude the use of halogenated systems, according to Adeka. It says intumescent HFFR types are often selected for cable applica- tions due to their combination of flame retardancy
Table1: Fire resistance data for TPU containing ADK STAB FP-2600U (polyether-type TPU with hardness of 85 Shore A)
Flame retardant (wt%) LOI (%)
UL-94V Elongation (%) Source: Adeka Corp 26 COMPOUNDING WORLD | May 2022
1.6mm 2.0mm
TPU 0
22
No rating No rating 711
TPU+FP-2600U 32 36
V-0 V-0 600
Below: Avient has launched new grades for optical fibre microtubes and jacketing
performance and smoke suppression. Adeka’s HFFR additive portfolio includes a P-N (phosphorus-nitrogen) intumescent range, as well as organophosphates and NO-alkyl based flame retardants. The company says the ADK STAB FP-2000 series of intumescent HFFRs for plastics have been proven in cable sheathing. ADK STAB FP-2500S is said to enable PE, PP/SEBS and PE/ EVA cable sheathing grades to pass UL-94V V-0 at a 20-30% loading. Depending on the specific formulation, the company says it can also enable compounds to pass the UL VW-1 North American vertical cable flame test standard. The latest addition to Adeka’s intumescent flame
retardant range is ADK STAB FP-2600U, which is targeted at thermoplastic polyurethane (TPU) polymers. With good mechanical strength, wear resistance and chemical resistance, TPUs are well suited to applications exposed to abrasion, such as robot cables. Tests carried out by the company on a TPU wire and cable compound indicate that ADK STAB FP-2600U provides a high level of flame retardancy without sacrificing mechanical properties such as flexibility, which is one of the prime reasons for selecting a TPU (Table 1). Furthermore, cone calorimeter (CCM) smoke density test results show the fire retardant reduced and suppressed smoke emission compared to alternative FR system (Figure 1).
Additive gains The wire and cable market is a key target for Evonik’s additive product lines. In particular, the company says its organo-modified siloxane (OMS) additive chemistry, which it markets under the Tegomer and Tegopren brand names, is able to allow increased loading of flame retardant addi- tives with minimal impact on mechanical perfor- mance while simultaneously lifting compound output rates. According to Evonik, Tegomer FR 100 siloxane
EVA, Tegomer V-Si 4042 reactive polysiloxane, and Tegopren 6879 filler surface treatment offer high temperature resistance and do not generate
www.compoundingworld.com
IMAGE: AVIENT
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
