EuroWire July 2022

Technical Article

Estane® ZHF 90AT2 NAT 055

Estane® ZHF 58202 NAT 02

Estane® ZHF 90AT8H NAT 02

Estane® ZHF 85AT8 MATT 01

Estane® ZHF 95AP7 NAT 01

Physical properties

Test method Unit

Hardness

ISO 868

Shore A

91

89

87

85

95

Specific gravity

ISO 2781

g/cm 3

1.24

1.23

1.21

1.14

1.39

Tensile strength at break

VDE282

MPa

22

28

27

50

20

Elongation at break

%

460

630

524

550

320

Tear strength nicked

ISO34-1B

kN/m

72

-

53

55

94

Abrasion resistance

ISO 4649

mm 3

49

65

36

40

110

Vertical burn

UL 94

-

V2 (1.9mm)

V2 (2mm)

V0 (0.8mm)

V2 (2mm)

V0 (2mm)

LOI

ASTM D-2863

%

24

25

25

24

30

Yellow card No Table 2 : Mechanical properties of Estane ZHF90AT2 NAT 055, Estane ZHF 58202 NAT 02, Estane ZHF 90AT8H NAT 02, Estane ZHF 85AT8 MATT 01 and Estane ZHF 95AP7 NAT 01 Yes No Yes No

Key features: 1 – High mechanicals 2 – Passing cable flame test (CFT) on small diameter cables 3 – High heat resistance: UL 105°C rating 4 – Hydrolytic stability 5 – Easy processing 6 – Global regulatory compliance 7 – UL94 V0 rating, high LOI 8 – VDE 282 capable The tests performed on the above-mentioned features are highlighted in the following points. 3.1 Mechanical properties (see Table 3) Mechanical properties were measured on extruded 1mm strip. 3.2 Cable extrusion +mechanical testing + cable flame test (CFT) To verify the actual flame-retardant, mechanical and extrudability properties, Estane ZHF 90AM9 NAT 01 was extruded under the following conditions: • Extruder set-up: extruder ø75 – PUR screw – torpedo ø3.8mm – die ø5.3mm • Temperature profile (fromhopper to die): 160-175-190-195-190 190-190°C • Cable ø5.3mm (0.9mm average jacket thickness) – screw speed 24 rpm, line speed 48m/min. Easy extrudability observed Test results, mechanical and CFT, according to UL1581 sec.1061 after 24 hours from the extrusion: • Tensile strength: 27.08 N/mm 2 (VDE: 250mm/min) • Elongation: 499.18 per cent (VDE: 250mm/min) • Cable flame test (UL1581 s.1061) passed in all three different samples 3.3 Cone calorimetry testing The cone calorimeter test is at present the most advanced method of assessing a material’s reaction to fire. The method follows the procedure as given in ISO 5660-1:1993(E). Additionally, measurements of smoke production and production of toxic gases can be performed during the test. The test gives a possibility to evaluate: • Ignitability • Combustibility • Smoke production • Production of toxic gases 3.3.1 Test principle and method The surface of the test specimen is exposed to a constant level of heat irradiance, within the range 0-100kW/m 2 , from a conical

Physical properties

Test method Unit

Value

Hardness

ISO 868

Shore A

90

Specific gravity

ISO 2781

g/cm 3

1.28

Tensile strength at break

ISO 527

MPa

32

Elongation at break

%

458

Tear strength nicked

ISO34-1B

kN/m 70

Abrasion resistance

ISO 4649

mm 3

82

Vertical burn

UL 94

-

V0 (2mm)

LOI

ASTM D-2863

%

27

Yellow card

No

Table 3 : Mechanical properties of Estane ZHF90AM9 NAT 01

heater. Volatile gases from the heated specimen are ignited by an electrical spark igniter. Combustion gases are collected by an exhaust hood for further analysis. This gas analysis makes it possible to calculate the heat release rate and to assess the production of toxic gases from the specimen. Smoke production is assessed by measuring attenuation of a laser beam in the exhaust duct. The attenuation is related to volume flow, resulting in a measure of smoke density called smoke extinction area (m 2 /s). The specimen is mounted on a load cell, which records the mass loss rate of the specimen during combustion. A thorough analysis requires testing at several irradiance levels. Typical levels are 25, 30, 35, 50 and 75kW/m 2 . The cone calorimeter test is very well suited to quantify a material’s reaction to fire. The test results can give information on how to improve the tested product. Compression moulded samples with a surface area of 100x100mm and a thickness of 3mm are placed horizontally, with 25mm between the plate and the cone heater. No grid is placed over the sample and a heat flux of 35kW/m 2 is applied. The results are detailed below.

The following materials were tested: • Estane ZHF 90AT2 NAT 055 • Estane ZHF 58202 NAT 02

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July 2022