Dow Silastic E RTV Silicone Rubber

CONTACT REP

Description for Dow Silastic E RTV Silicone Rubber

Good tear resistance, low durometer, long working time, high elongation.

Brand	Silastic
Application Type	Mold-Making
1 Part or 2 Part	2-Part
Material Form	Liquid
Manufacturer	Dow
Chemistry	Silicone rubber
Cure Method	Base/Curing Agent, Heat
Cure Temperature (°C)	25
Cure Time (min)	1,440
Viscosity (cPs)	55000 (mPa-s), Pourable
Color	White
Key Specifications	FDA (U.S. Food & Drug Administration) and/or CFIA (Canadian Food Inspection Agency): FDA 21 CFR 177.2600

Best Practices for Dow Silastic E RTV Silicone Rubber

Register for FREE to view more details

Why register?

View Technical Details
View Test Methods
View Key Specifications
View Similar Materials
Save your Project Searches

See what Gluespec offers

Sign up now Already registered? Sign in!

Email: *

Password: *

Confirm Password: *

Do you prefer to see data in °F or °C?

First Name: *

Last Name: *

Phone: *

Company Name: *

Address: *

Postal Code: *

Country: *

Job Function: *

Industry: *

Describe: *

I agree to the terms of use *

*: Required

Technical Data for Dow Silastic E RTV Silicone Rubber

*See Terms of Use Below

Overview

Application Type
- Casting / Moldmaking - Mold-Making
1 Part or 2 Part
- 2-Part
Material Form
- Liquid
Chemistry
- Silicone - Silicone rubber
Cure Method
- Heat
- 2-Part Cure - Base/Curing Agent
Color
- White
Key Specifications
- FDA (U.S. Food & Drug Administration) and/or CFIA (Canadian Food Inspection Agency) : 177.2600 - FDA 21 CFR 177.2600
Brand
- Silastic

Specifications

Cure Specs

Cure Temperature (°C)	25	Test Method
Cure Time (min)	1,440	Test Method
Viscosity (cPs)	55000 (mPa-s), Pourable	Test Method
Linear Shrinkage (%)	0.10	Test Method
Work / Pot Time (min)	Long, 120	Test Method
Mix Ratio	10:1 (by volume), 10:1 (by weight)

Bond Strength

General Bond Strength (psi)	High
Tear Strength (piw)	110 (ppi), Tear Resistance	Test Method
Tensile Strength (psi)	800	Test Method

Hardness

Shore A Hardness	37, 35	Test Method
Elongation (%)	350, High	Test Method
Flexibility	Flexible

Other Properties

Specific Gravity	1.140	Test Method
Flash Point (°F)	212.0

Business Information

Shelf Life Details	Silastic E RTV Silicone Rubber and its curing agent should be stored in closed containers at or below room temperature. The materials have a shelf life of 12 months from date of manufacture. Refer to product packaging for “Use By” date.
Shelf Life Type	from date of manufacture
Shelf Life (mon)	12

Best Practices for Dow Silastic E RTV Silicone Rubber

*See Terms of Use Below
1. Surface Preparation
  
  Patterns to be molded should be thoroughly cleaned to remove grease, oil and other surface contaminants. Certain contaminants sometimes used in moldmaking operations can prevent Silastic E RTV Silicone Rubber from curing. Care should also be taken to ensure that corners, crevices and draws are free of dirt or particles of foreign matter. A light “blow over” with compressed air is advised when the pattern has convoluted draws or undercuts. Then place the original model or pattern in a light frame of cardboard, foil, wood or other material. Allow approximately 1/4-inch clearance on all sides and over the top of the pattern. Attach the pattern securely to the bottom of the frame so that it does not float. A pattern release agent should then be wiped or sprayed on the pattern. A light coat of release agent on the sides and underside of the top of the frame will facilitate release.
2. Mixing
  
  Silastic E RTV Silicone Rubber base and its curing agent are produced in matched lots
  
  the two parts should be used in the kit form, as supplied. For the best curing results, use metal cans, clean glassware or unwaxed paper containers for mixing the base and curing agent. Silastic E RTV Silicone Rubber curing agent should be mixed into the base material just before use (with either manual or mechanical stirring) in the amount of one part curing agent to ten parts base by weight. Note: Varying the ratio of the Silastic E RTV Curing Agent will not hasten or slow the rate of cure. However, it will result in lowering the physical properties of the cured rubber.
3. Deairing/Degassing
  
  Inclusion of air during mixing may cause voids in the finished mold. Entrapped air may be removed by applying a vacuum of 28 to 29 inches of mercury. Under such a vacuum, the material will expand four to five times its original volume. As the froth collapses, the mixture will recede to its original volume. The vacuum should be held one or two minutes longer before releasing. Pressure casting may be substituted with equal success.
  
  With the curing agent added, 0.45 kg (1 lb) of Silastic E RTV Silicone Rubber will produce 409.7 cubic centimeters (25 cubic inches) of rubber.
4. Curing
  
  The cure of Silastic E RTV Silicone Rubber occurs by a reaction between the base polymer and the curing agent. This polymerization requires 24 hours after the addition of the curing agent at room temperature. This material will not revert or depolymerize, even under conditions of elevated temperature and confinement. Vulcanization can be accelerated by heating the catalyzed material. However, this will increase the shrinkage. The rate at which thick sections will set up depends on the size and shape of the piece.
Comparable Materials for Dow Silastic E RTV Silicone Rubber

*See Terms of Use Below

Spec Engine^® Results
- Silopren LSR 2630(Momentive)
  Momentive Silopren LSR 2630 is a 2-Part 2-Part Cure Silicone rubber Liquid used to Injection Molding
- Koeraform A 42(CHT)
  A pourable two-part, casting compound, addition cure silicone elastomer system, cure at ambient temperatures within 24 hours, exhibits excellent physical and electrical properties.
- Silopren LSR 2020(Momentive)
  Momentive Silopren LSR 2020 is a 2-Part 2-Part Cure Silicone rubber Liquid used to Injection Molding
- Compare All
Closest Results from this Manufacturer
- Silastic T-4 RTV Silicone Rubber w/ T-4 Curing Agent(Dow)
  High tear strength, suited for prototype design.
- Xiameter RTV-4230-E Silicone Rubber Kit(Dow)
   Easy release  High elongation  Minimum shrinkage  Long working time  Heat-accelerable cure  High strength  Tear resistance  Acceptable for food contact
- Silastic S RTV Silicone Rubber(Dow)
  • Fast RTV cure, very fast cure with even, low heat • Very low viscosity for easy mixing and deairing • Fast, RTV cure • High inhibition resistance
- Compare All