July 1999 TECHNICAL DATA SHEET

Cancels and replaces SIL 96 228 3

Description Silicone master-batch compound, vulcanising on heating after

addition of a vulcanizing agent (chosen according to the

transformation process).

Special properties · Excellent green strength

· Slight refreshening after prolonged storage

· No post curing

· Low shrinkage

· Low compression set

· Good heat stability, up to 225°C

· Good oil resistance (slight swelling)

· Wide possibilities of blending with the "Mix & Fix" masterbatch range

Characteristics Type (according to AFNOR T 40002)............. ......................... MVQ

Specific gravity at 25°C, approx................... .............................. 1.36

Natural colour....................................................... ........... .........beige

Properties after

working

After addition of 1.25% of 2,4-dichlorobenzoyl peroxide (50%) and

vulcanisation for 8 min. at 115°C (1).

After addition of 0.6% of 2.5-dimethyl bis -(tertiobutyl peroxy) 2.5-

hexane (75%) and vulcanisation for 10 min. at 170°C (2)

1. Mechanical properties

1.1 With no post curing

Shore A hardness, approx. ........................................

Tensile strength, MPa, approx. .................................

Elongation at break, % approx. .................................

Secant modulus at 100% elongation , MPa, approx...

Tear strength, kN/m, approx .....................................

Compression set (22 h / 177°C / 25%), % approx. ...

Rebound resilience, % approx. .................................

Linear shrinkage, % approx. ......................................

(1)

77

7.4

210

4.7

19

40

54

1.9

(2)

78

7.5

215

4.8

19

15

49

3.6

1.2 After post curing for 4 hours at 200°C

Shore A hardness, approx. ........................................

Tensile strength, MPa, approx. .................................

Elongation at break, % approx. .................................

Secant modulus at 100% elongation , MPa, approx...

Tear strength, kN/m, approx .....................................

Compression set (22 h / 177°C / 25%), % approx. ...

Rebound resilience, % approx. .................................

Linear shrinkage, % approx. ......................................

79

7.3

165

5.2

16

31

52

2.6

81

7.6

170

5.3

17

10

48

4.3

Properties after

working

(cont’d)

2 . Heat stability

2.1 Properties after 7 days at 177°C

Shore A hardness, approx..........................................

Tensile strength, MPa, approx....................................

Elongation at break, %, approx...................................

Tear strength, kN/m, approx........................................

(1)

79

7.2

185

16

(2)

80

7

175

19

2.2 Properties after 3 days at 200°C

Shore A hardness, approx..........................................

Tensile strength, MPa, approx....................................

Elongation at break, %, approx...................................

Tear strength, kN/m, approx........................................

78

6.4

155

16

79

6.9

170

17

2.3 Properties after 7 days at 200°C

Shore A hardness, approx..........................................

Tensile strength, MPa, approx....................................

Elongation at break, %, approx...................................

Tear strength, kN/m, approx........................................

79

6.7

185

14

80

6.2

140

18

2.4 Properties after 10 days at 200°C

Shore A hardness, approx..........................................

Tensile strength, MPa, approx....................................

Elongation at break, %, approx...................................

Tear strength, kN/m, approx........................................

77

6.4

155

15

81

6.3

170

17

2.5 Properties after 3 days at 225°C

Shore A hardness, approx..........................................

Tensile strength, MPa, approx....................................

Elongation at break, %, approx...................................

Tear strength, kN/m, approx........................................

77

6

160

14

79

5.5

140

16

3. Hot oil resistance

After the addition of 0.6% 2.5 bis-dimethyl (tertiobutylperoxy) -

2.5hexane (75%) and vulcanization at 170°C

Properties after immersion for 70 hours at 150°C (3)

Properties after immersion for 7 days at 150°C (4)

3.1 In ASTM 1 oil

Shore A hardness, approx. ........................................

Tensile strength,MPa, approx. ..................................

Elongation at break, % approx. .................................

Volume, approx ........................................................

(3)

79

7.7

180

3

(4)

78

7.1

190

3

3.2 In IRM 902 oil

Shore A hardness, approx. ........................................

Tensile strength,MPa, approx. ..................................

Elongation at break, % approx. .................................

Volume, approx ........................................................

74

7.6

185

8

74

7.3

205

9

Properties after

working

(cont’d)

3.3 In IRM 903 oil

Shore A hardness, approx. ........................................

Tensile strength, MPa, approx. .................................

Elongation at break, % approx. .................................

Volume, approx ........................................................

60

6.8

205

33

57

6.1

180

34

3.4 In 15W40 Motor oil

Shore A hardness, approx. ........................................

Tensile strength, MPa, approx. .................................

Elongation at break, % approx. .................................

Volume, approx ........................................................

70

6.5

210

14

67

6.3

215

14

Applications RHODORSIL MF 280 U is recommended for moulding, injection

and extrusion of articles with good mechanical properties (notably

in low compression sets). The use in blending with MF 240 U for

products exposed to oils (with or without an insert) and for roller mill

coatings.

Packaging RHODORSIL MF 280 U is delivered in 25 kg reinforced cardboard

boxes or in 500kg containers.

Storage and

shelf life

RHODORSIL MF 280 U may be stored in its original unopened

packaging at a temperature below 40°C for up to 18 months from

the date of manufacture marked clearly on the packaging.

Past this date, Rhodia Silicones no longer guarantees that the

product meets the sales specifications.

Safety Consult the Safety Data Sheet for RHODORSIL MF 280 U.

Warning to users The information contained in this document is given in good faith

based on our current knowledge. It is only an indication and is in no

way binding, particularly as regards infringement of or prejudice to

third party rights through the use of our products.

RHODIA SILICONES GUARANTEES THAT ITS PRODUCTS

COMPLY WITH ITS SALES SPECIFICATIONS.

This information must on no account be used as a substitute for

necessary prior tests which alone can ensure that a product is

suitable for a given use.

Users are responsible for ensuring compliance with local legislation

and for obtaining the necessary certifications and authorisations.

Users are requested to check that they are in possession of the

latest version of this document and RHODIA SILICONES is at their

disposal to supply any additional information.