development and analysis of materials for rubber ... - utb

November 13th, 2019

Dr Jakub Kadlcak

Head of R&D Automotive

Compounds under Dynamic Loadings

Development and Analysis of Materials

for Rubber Seals in AutomotiveCompounds Under Dynamical Loading

Gumference, Centre of Polymer

Systems, Zlín

Jakub Kadlcak, Matthias Soddemann

Datwyler Sealing Solutions

Introduction

Material Development

Results Discussion &

Conclusions

Agenda

Datwyler Sealing Solutions

Swiss origin, established in 1915

Revenues of more than

CHF 1,400 million

Focused industrial player with two

divisions: Sealing Solutions &

Technical Components

Listed on the SIX Swiss Exchange

Stability and

strength of a large

industrial group

International presence with more than 7,000 employees

Healthcare Automotive

Pennsauken

USAAlken

Belgium

Pregnana,

Montegaldella,

ItalyViadanica,

Italy

Schattdorf

Schweiz

Kesurdi

India

Cleebronn

Germany

Karlsbad-Ittersbach

Germany Daegu

Korea

<General Industries

Wuxi, Ningguo

China

Silao

Mexico

Vandalia

USANovy Bydzov,

Czech Republic

Malyn

Ukraine

Ontario

USA

São Leopoldo

Brazil

Americas 15%

1,300 Employees

Europe 45%

3,000 Employees

Asia 40%

2,600 Employees

Waltershausen

Germany

Dallas

USA

Montgomery

USA

Gray

USA

Middletown

USA (2018)

Development and Analysis of Materials for Rubber Seals in Automotive | November 13th, 2019 | © Datwyler, www.datwyler.com4

Multi-market know-how

Applications:

Brake systems

Fuel and tank systems

CNG and LPG

Exhaust gas treatment

Powertrain, suspension

Thermoplasts and LSR

E-Mobility, electrification

Applications:

Prefilled syringe and cartridge

drug delivery systems

Medical devices

Elastomeric closures and

aluminium seals

Applications:

Consumer Goods

Civil Engineering

Oil & Gas

Power tools, valves & fittings

Machines for process industries

Water and waste water

Hydraulic and pneumatic

GENERAL INDUSTRIESAUTOMOTIVEHEALTHCARE


2.5 billion sealing parts for the automotive industry each year

Introduction

Introduction to the Problem

Challenge: A plant closure of a material supplier

A source of raw

materials, chemicals

The mixing of compounds and

production of parts

Assembly of parts

(Tier 1 / OEM)

1. A raw material supplier closes its plant – the product at ’’end of life’’

2. A raw material supplier moves production from one place to another

The aim of suppliers is usually to produce a product of the same quality

Not always possible – different environmental/production conditions, a new technology, etc.


Material Development

In the case described here, an elastomer supplier has moved a production line from one plant to

another.

The goal was to prepare a compound based on a new elastomer but showing the same processing

and performance behaviour as the original compound.

Step one:

1:1 exchange of the original elastomer with other two elastomers of ‘‘identical’’ grade

Problem Solving

Polymer Producer Plant

Original Original Closed

Elastomer 1 Original New

Elastomer 2 Alternative -


Material phr phr phr

Compound coding X 3606-01 X 3606-02 X 3606-03

Original elastomer 100.0 ---- ----

Elastomer 1 ---- 100.0 ----

Elastomer 2 ---- ---- 100.0

Carbon black

Paraffinic oil

Anti-ageing agents

Vulcanisation co-agents

Peroxide 3.6 3.6 3.6

Compound CompositionStep One: 1:1 Exchange of the Original Elastomer


Rheological PropertiesStep One

0

5

10

15

20

25

0 1 2 3 4 5 6

To

rqu

e / d

Nm

Time / min

X 3606-02

X 3606-01

X 3606-03

Characteristic X 3606-01 X 3606-02 X 3606-03

ML 1.4 1.4 1.2

MH 18.6 21.7 17.0

ts2 0.4 0.4 0.4

t30 0.5 0.5 0.6

t70 1.1 1.1 1.2


Physical PropertiesStep One

66

69

66

65

66

67

68

69

Microhardness / °IRHD

X 3606-01 X 3606-02 X 3606-03

15.5 15.5

16.4

15.0

15.5

16.0

16.5

Tensile Strength / N.mm-2

X 3606-01 X 3606-02 X 3606-03

369

283

376

0

100

200

300

400

Elongation at Brake / %

X 3606-01 X 3606-02 X 3606-03

2.8

3.7

2.9

0.0

1.0

2.0

3.0

4.0

Modulus 100 / N.mm-2

X 3606-01 X 3606-02 X 3606-03

8.7

5.2

8.3

0

2

4

6

8

10

Tear Strength / N.mm-1

X 3606-01 X 3606-02 X 3606-03

14.5

8.7

15.8

0

5

10

15

20

Compression Set 24 h, 130 °C / %

X 3606-01 X 3606-02 X 3606-03

Other characteristics X 3606-01 X 3606-02 X 3606-03

Glass transition (DSC) / °C -54.5 ~ -54.0 ~ -53.0 ↓

Density / g.cm-3 1.09 1.09 1.09


Compound CompositionStep Two: The Adjustment of the Vulcanisation System Level

Material phr phr

Compound coding X 3606-01 X 3606-06

Original elastomer 100.0 ----

Elastomer 1 ---- 100.0

Elastomer 2 ---- ----

Carbon black

Paraffinic oil

Anti-ageing agents

Vulcanisation activators and accelerators

Peroxide 3.6 ↓ ~ 20 %


0

5

10

15

20

25

0 1 2 3 4 5 6

To

rqu

e/ d

Nm

Time / min

X 3606-06

Characteristic X 3606-01 X 3606-06 X 3606-03

ML 1.4 1.4 1.2

MH 18.6 18.9 17.0

ts2 0.4 0.4 0.4

t30 0.5 0.6 0.6

t70 1.1 1.1 1.2

Rheological PropertiesStep Two

X 3606-01 X 3606-03


14.5 13.815.8

0

5

10

15

20


X 3606-01 X 3606-06 X 3606-03

8.7

6.1

8.3

0

2

4

6

8

10


X 3606-01 X 3606-06 X 3606-03

2.8 2.8 2.9

0.0

1.0

2.0

3.0

4.0


X 3606-01 X 3606-06 X 3606-03

369 359 376

0

100

200

300

400


X 3606-01 X 3606-06 X 3606-03

15.515.3

16.4

15.0

15.5

16.0

16.5


X 3606-01 X 3606-06 X 3606-03

66

67

66

65

66

67

68

69


X 3606-01 X 3606-06 X 3606-03

Physical PropertiesStep Two



Density / g.cm-3 1.09 1.09 1.09


Physical PropertiesStep One

66

69

66

65

66

67

68

69


X 3606-01 X 3606-02 X 3606-03

15.5 15.5

16.4

15.0

15.5

16.0

16.5


X 3606-01 X 3606-02 X 3606-03

369

283

376

0

100

200

300

400


X 3606-01 X 3606-02 X 3606-03

2.8

3.7

2.9

0.0

1.0

2.0

3.0

4.0


X 3606-01 X 3606-02 X 3606-03

8.7

5.2

8.3

0

2

4

6

8

10


X 3606-01 X 3606-02 X 3606-03

14.5

8.7

15.8

0

5

10

15

20


X 3606-01 X 3606-02 X 3606-03



Density / g.cm-3 1.09 1.09 1.09


14.5 13.815.8

0

5

10

15

20


X 3606-01 X 3606-06 X 3606-03

8.7

6.1

8.3

0

2

4

6

8

10


X 3606-01 X 3606-06 X 3606-03

2.8 2.8 2.9

0.0

1.0

2.0

3.0

4.0


X 3606-01 X 3606-06 X 3606-03

369 359 376

0

100

200

300

400


X 3606-01 X 3606-06 X 3606-03

15.515.3

16.4

15.0

15.5

16.0

16.5


X 3606-01 X 3606-06 X 3606-03

66

67

66

65

66

67

68

69


X 3606-01 X 3606-06 X 3606-03

Physical PropertiesStep Two



Density / g/cm-3 1.09 1.09 1.09


1

10

100

1 000

0.001 0.01 0.1 1 10 100

Sh

ea

r M

od

uli

G’,G

’’/

kP

a

Shear Rate / s-1

Series1 Series2 Series3 Series4 Series5 Series6

broad

MWD

low

MW

high

MW

Raw Elastomer InvestigationCross-Over Point

narrow

MWD

Original G’ Original G’’ Elastomer1 G’ Elastomer1 G’’ Elastomer2 G’ Elastomer2 G’’


100

1 000

10 000

100 000

1 000 000

0.001 0.01 0.1 1 10 100

Vis

cosity

ƞ’/

Pa

.s

Shear Rate / s-1

Series1 Series2 Series3

Raw Elastomer InvestigationShear Thinning

Original Elastomer 2Elastomer 1


1 – 10 s-1

compression

moulding

0

100

200

300

400

500

600

700

800

900

1000

0.01 0.1 1 10 100 1000

Sh

ea

r M

od

ulu

s G

’ / kP

a

Shear Strain / %

Strain Sweep on CompoundsPayne Effect (Loading & Unloading Cycle)

X 3606-01

X 3606-03

X 3606-06Rubber compound Softening / kPa Conditioning / kPa

X 3606-01 790.9 377.6

X 3606-06 816.3 383.5

X 3606-03 708.1 278.7


LAOS on CompoundsLarge Amplitude Oscillatory Strain

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

9.0

10.0

1

10

100

1000

0.01 0.1 1 10 100

Ta

nD

elta

/ -

Sh

ea

r M

od

ulu

s G

' / k

Pa

Shear Rate / s-1

X3606-01 G' X3606-03 G' X3606-06 G'X3606-01 tanD X3606-03 tanD X3606-06 tanD


Results Discussion & Conclusions

Three polymers have been analysed and the investigation has shown differences in

molecular structure

This leads to differences in vulcanisation characteristics, physical properties and

processing even suppliers declare the polymers to be the same

Adjustment of the compound recipe was necessary

Although optimised recipe, new polymer is showing major deterioration in tear strength

Limitations in performance of the new polymer compared to the original one

The endurance (behaviour under dynamical loadings) of such compound will be ultimately

affected

Results Discussion & Conclusions


Endurance TestBefore Testing

Original elastomer Elastomer 1

Under high vacuum


Endurance TestAfter Testing

Original elastomer Elastomer 1

Test OK High wear resulting in leakage

Test not OK

Higher wear


The real challenge starts in serial production of parts

Limitations in the performance of the base elastomer will

inevitably affect the performance of final parts

Material specification provided by customers must be

met

• Adjustment in the recipe (a different polymer grade, a

combination of polymers)

• Adjustments in mixing process

• Adjustments in processing conditions (temperature, time,…)

Improvement in tear strength will negatively affect the

compression set – balance

Results Discussion

A.Y. Coran. Vulcanisation. J.E. Mark, B. Erman, F.R. Eirich. Science

and Technology of Rubber. Elsevier Academic Press 2005; 7: p. 321–

366. ISBN: 0-12-464786-3.


AB

✔

✔

Tear StrengthISO 34-1, Method B, Unnicked vs. ISO 34-1, Method A (trousers)

Specimen No.

Tear Strength

Method B, Unnicked

/ N.mm-1

Tear Strength

Method A

/ N.mm-1

Limit ≥ 30 N.mm-1 Limit ≥ 6 N.mm-1

B1S1 29.6 5.3

B1S2 30.5 4.7

B1S3 36.3 4.7

B2S1 34.6 4.9

B2S2 33.6 4.6

B2S3 33.8 4.6


International Standard: DIN ISO 34-1

De Mattia TestOriginal vs New Compound

0

2

4

6

8

10

12

14

16

18

0 500 1000 1500 2000 2500

0

2

4

6

8

10

12

14

16

18

0 2000 4000 6000 8000 10000

Original compound

No. of cycles in average to reach L+10 mm

crack is 5700

New Compound

No. of cycles in average to reach L+10 mm

crack is 1600


Intrinsic Strength Analysis


Sc = T + F ,

where T is tearing energy release rate, F is cutting energy release

rate

The intrinsic strength respective endurance limit of

material T0 describes the minimal energy required for the

rupture of a polymer chain

Dependent primarily on details of the polymer network

(driven by crosslink-to-crosslink length of polymer chain)

and shows the weakest bond in the main polymer chain,

whereas the methodology based on cutting protocol firstly

evaluate the Intrinsic cutting energy:

T0 = b · Sc,

where T0 is the endurance limit proportional to Sc via the use of a

constant b which is a function of the blade sharpness

A. Machu, Fracture Behaviour of Rubber Used for Sealing Application at Fatigue Loading Conditions. Master Thesis.

Tomas Bata University. 2018.

Intrinsic Strength Analysis

0

200

400

600

800

1 000

1 200

1 400

1 600

1 800

2 000

0.01 0.025 0.05 0.1 0.2 0.3 0.5

Intr

insic

Cutt

ing

En

erg

y S

c/ J.m

-2

Strain / -

450931 450932

Material

Intrinsic Cutting

Energy Sc

/ J.m-2

Threshold

T0

/ J.m-2

Original 690.2 96.6

New

Compound695.1 97.3

Old compound New compound


A. Machu, Fracture Behaviour of Rubber Used for Sealing Application at Fatigue Loading Conditions. Master Thesis.

Tomas Bata University. 2018.

In next stage we would like to focus on finding correlations between existing, generally

accepted methods and alternative, new methods to evaluate tear resistance of materials

Fracture behaviour of EPDM compounds for sealing application at dynamic loading

conditions

Further Steps…


Matching the Development with the Application

Vulcanization Process

-

Final Product

Production of

Compound

Compound Development

Processing

-

Moulding

Any changes to the formulation can have a major impact

on the processing and performance of the final product!


TA Instruments for performing rheological testing.

Dr. Radek Stoček and Centre of Polymer Systems for elaborating on the analysis of

fracture behaviour of our compounds.

Acknowledgements

development and analysis of materials for rubber ... - utb

Documents