Arkema functional polyolefinsfor cable compounds

EVATANEEVATANE®®

LOTRYLLOTRYL®®

LOTADERLOTADER®®

OREVACOREVAC®®

October 2002

2

Evatane®- Lotryl®- Lotader®- Orevac®

HFFR: Halogen Free Flame RetardantWhy HFFR? p 3Atofina functional polyolefins for cables p 6Standard formulation p 9Resin selection p 11Coupling agents p 14Ageing p 17Crosslinking p 18Temperature requirements p 21

Power cableArkema resins in power cable p 22Internal semi conductor layer p 24Insulation layer p 25External semi conductor layer p 26Sheathing/jacketing p 27

The information contained herein is to the best of our knowledge accurate, but since the circumstances and conditions in which it may be used are beyond our control, we do not accept liability for any loss or damage, however arising, which results directly or indirectly from the use of such information, nor we offer any warranty of immunity against patent infringement.

3

Why halogen free compounds?

PVC is still the main resin used in the cable industry.However, three main drawbacks have forced the development of alternative halogen free materialsFire behavior of PVC :

Formation of black smokeRelease of chlorine derivatives

Environmental considerations :PVC under environment pressure

Limited temperature resistance (110°C)

With its range of functional polyolefins, Arkema stands as a partner of choice to cable manufacturers who expect innovative solutions to the most complex of problems.

4

HFFR:Alternative to PVC

Polyolefins (PE, EVA, EMA, EBA) are good candidates for the substitution of PVC in cables. Benefits are:

Good combustion properties• Low smoke emission• Anti-drip

Excellent dielectric propertiesGood physical properties - CrosslinkableRecyclability Good performance/price balance

But limited natural fire resistance: the addition of mineral flame retardants such as Al(OH)3, Mg(OH)2 and/or others is necessary to meet flame retardancy requirements.

As they accept high content of filler (due to their high polarity), EVATANE ®and LOTRYL ® are the materials of choice

5

Where HFFR

Medium -High Voltage cable>1KV to 600 KV

For medium voltage or high voltage, only the sheathing layer (7) is halogen free.

Low voltage < 1KV

HFFR can be used in insulation, bedding and sheathing of low voltage cables

1

2

3

45

6

7

6

Grades

VA Content (%)

Melt Index (g/10 min)

Melting point (°C)

Vicat point (°C)

Tensile Strength at break (Mpa)

Elongation at break (%)

Hardness Shore A

18-150 17 – 19 135 – 175 79 43 5 500 – 800 84

18-500 17 – 19 450 – 550 74 < 40 4 500 – 800 80

20-20 19 – 21 17 – 23 79 49 12,5 500 – 800 84

24-03 23 – 25 2,5 – 3,5 79 45 29 700 – 800 85

28-03 26 – 28 3 – 4,5 75 44 33 700 – 1000 83

28-05 27 – 29 5 – 8 73 43 33 700 – 1000 82

28-25 27 – 29 22 – 29 72 41 13 700 – 1000 76

28-40 27 – 29 35 – 45 72 40 11 700 – 1000 76

28-150 27 – 29 135 – 175 67 < 40 6 700 – 1000 70

28-420 27 – 29 370 – 470 67 < 40 2,5 700 – 1000 62

28-800 27 – 29 700 – 900 64 < 40 1,5 300 57

33-35 32 – 34 22 – 29 60 < 40 12 800 – 1000 66

33-45 32 – 34 38 - 48 60 < 40 10,5 800 – 1000 64

33-400 32 – 34 350 - 450 59 < 40 2,5 800 – 1000 45

40-55 38 - 41 48 - 62 50 < 40 5 1000 46

EVATANE: wide range of vinyl acetate content and melt index

Evatane®: EVA copolymers

7

Base Grades Ester content Melt index Melting Tensile strength Elongation at Flexural% (g/10 min) point (°C) at break (Mpa) break (%) modulus (Mpa) Shore A Shore D

7 BA 01 6 - 8 1 - 1,5% 107 17 700 85 - 42E 17 BA 04 16 - 19 3,5 - 4,5 91 13 700 45 - 32B 17 BA 07 16 - 19 6,5 - 8 89 12 700 40 - 30A 30 BA 02 28 - 32 1,5 - 2,5 78 6 850 9 75 -

35 BA 40 33 - 37 35 - 45 67 2 300 - 70 -9 MA 02 8,5 - 10,5 1,8 - 2,6 99 16 750 88.5 - 3815 MA 03 13,5 - 16 2,3 - 3,3 89 14 700 50 - 29

E 16 MA 003 14 - 17 0,25 - 0,35 96 22 650 60 - 35M 18 MA 02 17 - 20 2 - 3 87 15 700 50 - 25A 20 MA 08 19 - 22 7 - 9 80 10 800 20 83 -

24 MA 005 23 - 26 0,4 - 0,6 70 20 700 18 84 -28 MA 07 26 - 30 6 - 8 65 7 900 10 76 -29 MA 03 27 - 31 2 - 3,5 61 6 900 8 75 -

Hardness

LOTRYL are random ethylene / acrylic ester copolymers.--- (CH2 - CH2 -)x ---- (CH2 - CH - ) ---

Ethylene IO = C – O - CH3 or C4H9

Methyl Acrylate Butyl Acrylate

Lotryl® EMA & EBA copolymers

8

Lotader® and Orevac®

Maleated polyolefinsLOTADER

Ethylene-butyl acrylate-maleic anhydride terpolymers

- (CH2 - CH2 -)x - (CH2 - CH - ) y - (CH2 - CH2 -) - (CH - CH - )zI I I

C = O O = C C = OI \ /

O - R O Butyl Acrylate Maleic anhydride

LOTADER GRADES

N BUTYL ACRYLATE

(w%)

MALEIC ANHYDRIDE

(w%)

3210 6 3.1

4210 6 3.8

3410 17.7 3.1

OREVAC GRADES

MFI (g/10min)

Tm (°C)

PE 18302 1 124

EVA 18211 3.5 75

PP CA100 10 167

OREVACMaleic anhydride grafted polyolefins

-- (CH2 - CH2)n -- CH2 - CH-ICH - CH2

I IO = C C = O

\ /O

9

HFFR standard formulations

Polyolefins + Filler + Coupling agent

Filler acceptance Flame resistance Cohesion

EVATANE®

LOTRYL®

LOTADER®

OREVAC®

50EVATANE® or LOTRYL®

PHRProduct

0,7Stabilizer

170Mineral flame retardant fillerAl(OH)3 or Mg( OH)3.

20OREVAC or LOTADER

30PE ( LD, HD,LL,VLD)

HFFR formulations are based on blends of ethylene copolymers (EVA, EMA, EBA) and Polyethylene (LD,LL,HD) to optimize flameretardancy , mechanical properties and cost .

Standard formulation

10

0

5

10

15

20

25

30

35

40

0 40 60 70

LDPE

EVA, EBA, EMA(30%Comonomer)

ATH content (wt%)

HFFR compounds : LOI*

Soft PVC LOI

LOI*: Limited Oxygen Index = minimum amount of oxygen in atmosphere to maintain combustion

In order to meet fire resistance a high amount of filler is required. EVATANE® and LOTRYL®

(EMA, EBA, EVA) provide better fire resistance due to their high filler acceptance.

LOI (%)

11

0

20

40

60

80

100

120

140

160

10 15 20 25 30 35

Lotryl or EVA Comonomer content (w%)

%E

lon

g. a

t b

reak

Evatane®, Lotryl® selection

Higher comonomercontent increases elongation at break and filler acceptance.

Lower melt index gives higher stress at break.

The selection of an appropriate grade is based on the compromise between acrylate content and MFI.

0

2

4

6

8

10

12

14

16

18

0 0.5 1 1.5 2 2.5 3

LOTRYL or EVA MFI (g/ 10 min @ 190°C/2.16kg)

Stre

ss a

t bre

ak (M

pa)

12

Evatane®, Lotryl® selection

Stress and elongation at break (%)for standard formulation

020406080

100120140160180

EVATANE 2803Lotryl 15 MA 03Lotryl 16 MA 003Lotryl 24 MA 005Lotryl 29 MA 03Lotryl 30 BA 02

% E

lon

gat

ion

024681012141618

Str

ess

at B

reak

(Mp

a) Arkema’s product range has been developed to cover the specifications of the cable industry

Recommended resins:Evatane® 28-03, 28-05

Lotryl® 30 BA02, Lotryl® 24 MA005,Lotryl® 29MA03, Lotryl® 16MA003

13

Evatane® brings a good performance at a competitive cost.

Due to their better thermal stability, Lotryl® is more appropriate for :

Higher processing temperatures Higher extrusion speed Better heat resistanceBetter chemical resistance.

especially to oil.

Choice of Evatane® versus Lotryl®

Ageing @ 175°C

0

20

40

60

80

100

120

0days 7days 14days 21days 28days 35days

Ageing time

Elo

ngat

ion

at b

reak

%

EVA compound Lotryl compound

Lotryl based compounds have better ageing resistance than EVA based compounds.

14

Selection of the appropriate coupling agent is an important issuefor HFFR compounds:

↓The use of reactive polymers such as LOTADER®, OREVAC®

improves fillers dispersion and adhesion with base polymer.↓

The use of a coupling agents allows to increase the tensile strength at break while keeping a good elongation at break.

↓LOTADER® and OREVAC® allow to reach cables specifications. Example : Mechanical specifications for Euro Tunnel Cable are strength at break >10 Mpa and Elongation >125%.

Why coupling agent?

15

0

2

4

6

8

10

12

14

EVA 2

8 %gr

afte

d

LOTA

DER 32

10

LOTA

DER 42

10

OREVAC

183

02

OREVA

C 930

4

Ten

sile S

tren

gth

(M

Pa)

0

20

40

60

80

100

120

140

160

elo

ng

atio

n a

t bre

ak (%

)

Effect of coupling agent

Tests run on thestandard formulation presented on page 9

Recommendations:

LOTADER® 3210, 4210

OREVAC® 18302

The use of a coupling agents allows to increase the tensile strength at break while keeping a good elongation at break

16

Coupling agent Unit Tensile strength

(MPa)

Elongation at break (%)

Lotader 3210 Internalmixer 13 135

Orevac 18302 Internalmixer 12 110

Customer results with Orevac 18302

Buss ortwin

screw 14 195

*:

Choice of LOTADER® versus OREVAC®

LOTADER® 3210: General purpose, versatile coupling agent.

OREVAC® 18302: Better compounding efficiency on twin screw extruders and Buss co-kneaders.

17

Ageing HFFR compounds

1211417813.425Lotader3210

155100

12412.522010.811Lotader3210

135100Lotryl 29MA03

13014.717615.225Lotader3210

155100

15014.719014.111Lotader3210

135100Lotryl 24MA005

12015.220014.725Lotader3210

155100

14012.825611.811Lotader3210

135100EVA 280328% VAMI 3

Elongation%

Tensile MPa

Elongation %

TensileMpa

PartsGradePartsPartsGrade

Aging :7days /180°CMechanical Properties

Coupling agentATHPolymer

18

Crosslinking

Main reasons for crosslinking

Improved Temperature resistanceImproved drip resistance when burningImproved creep resistance ( deformation under load)

Improved chemical resistance( stress crack)

Improved impact resistanceIncrease abrasion resistance

Example: T3 cable for automotive

Severe chemical environment (oil, lubricants, battery acid)

19

Crosslinking technologies

Peroxide (DCP)

Radiation10-15 Mrad

Silanes

SioplasDry silane(Monosil)

Peroxide

Heat

- H2

e-e-

e-

SiOR

OROR Heat Si

OR

RO OR

X 2

WaterCatalyst

Si

SiO

RO

OR

OR

ORPeroxide

20

Crosslinking solutions

The compounds using Lotryl® as base polymer and Lotader® orOrevac® coupling agents have been successfully crosslinked by E beam technology, peroxides, silanes.

The selection of appropriate grades should be made according to the technologies used.

Examples:E beam and silane for T3 automotive cablePeroxide and silane for medium and high voltage cable.

21

Formulation: LOTRYL® 24MA005 + PE + LOTADER® 3210/OREVAC® 18302 + ATH/MDH

Material selection Temperature requirements

Material selection Material selection Temperature requirementsTemperature requirements

T1T1

T2T2

T3T3

T4T4

T5T5

T6T6

85°C

105°C

125°C

150°C

175°C

200°C

PVCPVCbrominated plasticizer

antimony

PPPPLOTRYLmodified

ETFEETFEPVDFPVDF

FEPFEP

PTFEPTFE

PFAPFApr

ice

perf

orm

ance

TPETPEHFFR

XX--HFFRHFFRLOTRYL®LOTRYL®EVATANE®EVATANE®LOTADER®LOTADER®

OREVAC®OREVAC®

HFFRHFFRLOTRYL®, EVATANE®LOTRYL®, EVATANE®LOTADER®, OREVAC®LOTADER®, OREVAC®

22

POWER CABLEMEDIUM AND HIGH VOLTAGE

23

1: Copper conductor2: Internal semi conductor:

Based on LOTRYL® 17BA073: Insulation XLDPE -XLLDPE

Using “CLEAN” LOTRYL®

17BA044: External semi conductor

Based on EVATANE® 3325 or 33455: Concentric conductor6 : Copper layer7 : HFFR sheathing :

Evatane®/Lotryl®

1

2

3

4

56

7

Arkema resins inMedium/High Voltage Cable

24

Medium/High Voltage Cable

2. Internal semi conductor layerTo eliminate electrical tracking and arcing discharges

Needs good thermal stability as conductor temperature can reach 90°CNeeds good adhesion to conductor and to insulation layerNeeds extremely homogenous dispersion of the carbon filler (40%)Needs to be easy to process, good smoothness (thin layer)Needs to be crosslinked by peroxyde and extruded at low temperature 130°C-140°C

Arkema recommendationsLOTRYL® 17BA07 or 17BA04 for their high polarity, good thermal stability and fluidity.LOTADER 3210 (20% to 30% in dilution in LOTRYL® ) in order to

optimize dispersion with treated carbon filler (coupling agent) and adhesion to conductor.

25

3. Insulation Layer:To prevent electrical breakdown

Needs to eliminate water-treeing which results in insulation failure of the cable.Needs to improve environmental stress cracking resistance.

Arkema recommendations

Main products used are crosslinked LLDPE,LDPE or EPDM Adding 15% LOTRYL® 17BA04 or 18MA02 will prevent water treeing and improve stress cracking resistance.

Medium/High Voltage Cable

26

4. External Semi conductor:To provide electrical protection

Needs good peelability between external semiconductor (4) and insulation layer (3)

Arkema recommendationsPeroxide crosslinked EVATANE 33-25 or 33-45 based compound with carbon black (40 weight%).

Medium/High Voltage Cable

27

7. Sheathing- jacketing:To provide mechanical and thermal protection

Needs good mechanical resistanceNeeds high chemical resistanceNeeds to be flame resistant

Arkema recommendationsMineral filled HFFR compound based on EVATANE® with high VA content 28-03, 28-05 LOTRYL® with high acrylate content ( 30 BA 02, 29MA03)LOTADER ® 3210, OREVAC ® 18302

Medium/High Voltage Cable