Silpak, Inc

random1.jpg

Silicone Platinum RTV

Low Viscosity (R-2138 and R-2157)

Attention, open in a new window. PDFPrintE-mail

These Two-Part, Platinum RTV (Addition Cure) silicone rubbers designed for mold making, embedding, electrical applications, and thermal expanding tools. The controlled coefficient of thermal expansion makes these RTV ‘s ideal for casting pressure pads and for use as an advanced composite tooling rubber.  They are Low Viscosity and require an accurate mix ratio.


Physical Properties (TYPICAL VALUES): 24 hrs. @ 77F (25C)


R-2138 A/B

R-2157 A/B

Color:

Pinkish

Light Green

Mixed Viscosity@ R.T.:

30,000 CPS

30,000 CPS

Specific Gravity:

1.25

1.25

Mix Ratio A/B:

10/1

10/1

Durometer A Shore:

42

50

Tensile Strength (PSI):

750

650

Elongation %:

350

300

Tear Strength (PSI):

125

102


 


 



 


 


Shelf Life

6 months

6 months


Mixing Instructions: **(Scale Measurement Required)
The base and curing agent are mixed just before using. Mix 10 parts base to 1 part curing agent by weight. Automatic mixing equipment or manual mixing may be used to combine base and curing agent. Immediately after mixing, place the material in a vacuum chamber to remove entrapped air. As vacuum is drawn, the material will expand as much as four times its original volume. Remove from vacuum chamber and pour very gently, so as not to incorporate air into the material.

Inhibition:
Certain materials will cause inhibition or neutralizing of the curing agent: sulfur and organo-metallic salt containing compounds found in organic rubbers, and many condensation cure RTV, chloride solvents, and amines-epoxy. Inhibition may easily be determined by brushing a small quantity of these materials over a localized area of the part to be reproduced. If the material remains gummy or uncured after the curing time, then the part’s surface is acting as an inhibitor. **See Addition Cure Technical Data Sheet for inhibiting

TEMPERATURE

POT LIFE

CURE TIME

100 F

30 MIN

2 HOURS

150 F

10 MIN

30 MIN

300 F

----

5 MIN

 

 

 

 

The information and data contained herein are based on information we believe reliable. Each user of the material should thoroughly test any application and independently conclude satisfactory performance before commercializing. Suggestions of uses should not be taken as inducements to infringe on any particular patent.