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Description for Dow Silastic 591
Fast heat cure; low shrinkage; no cure by-products; low compression set.Brand Silastic Application Type Mold-Making 1 Part or 2 Part 2-Part Material Form Liquid Manufacturer Dow Chemistry Silicone rubber Cure Method Heat, Part A/Part B Cure Temperature (°C) 171, 200 Cure Time (min) Fast, 5.00, 0.13 to 0.23 Color Off White Key Specifications UL (Underwriters Laboratory), ULC (Underwriters Laboratories of Canada), NFPA (National Fire Protection Association): UL 94: UL 94 V-1 -
Technical Data for Dow Silastic 591
Overview
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Application Type
- Casting / Moldmaking - Mold-Making
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1 Part or 2 Part
- 2-Part
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Material Form
- Liquid
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Industry
- Textiles - Fabric coating
- Industrial - Business machine rollers, Sleeving
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Chemistry
- Silicone - Silicone rubber
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Application Method
- Dispenser - Meter mix equipment
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Cure Method
- Heat
- 2-Part Cure - Part A/Part B
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Color
- Off-White - Off White
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Key Specifications
- UL (Underwriters Laboratory), ULC (Underwriters Laboratories of Canada), NFPA (National Fire Protection Association) : UL 94 : V-1 - UL 94 V-1
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Brand
- Silastic
Specifications
Cure Specs
Cure Temperature (°C) 171, 200 Test Method Cure Time (min) Fast, 5.00, 0.13 to 0.23 Test Method Linear Shrinkage (%) Low Mix Ratio 1:1 (by volume) Bond Strength
Tear Strength (piw) 73 (ppi) Test Method Tensile Strength (psi) 485 Test Method Hardness
Shore A Hardness 51 Test Method Elongation (%) 4 Test Method Other Properties
Specific Gravity 1.540 Test Method Flash Point (°F) 212.0 % Solids (%) 100 Business Information
Shelf Life Details When stored at or below 32°C (90°F) in the original, unopened containers this product has a usable life of 18 months from the date of production. Shelf Life Type from the date of production. Shelf Life (mon) 18 -
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Best Practices for Dow Silastic 591
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Mixing
The A and B components are supplied strained and de-aired to be used as lot matched kits. Mix parts A and B in a 1:1 ratio. Meter mix equipment which pumps, meters and mixes the two components without the incorporation of air is strongly recommended for production.
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Deairing/Degassing
If air bubbles are entrapped during mixing the mixture must be thoroughly de-gassed under vacuum.
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Curing
SILASTIC 591 cures rapidly at elevated temperatures. A 2mm cross-section requires 8-14 seconds at 200°C (392°F). The cure time depends on the thickness and the cure temperature used. Cure can be inhibited by contact with certain materials such as amines, sulphur and tin complexes.
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Clean-Up
The uncured silicone can readily be removed by most hydrocarbon solvents. Polar solvents, such as ketones and alcohols, are not suitable.
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Comparable Materials for Dow Silastic 591
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Cure Temperature Test Methods
Cure Temperature | Cure Time Test Method |
---|---|
171°C | Press cured |
200°C |
Cure Time Test Methods
Cure Time | Test Method |
---|---|
Fast | |
5.00 min | Press cured |
0.13 to 0.23 min |
Work / Pot Time Test Methods
Work / Pot Time | Temperature |
---|
Tensile Strength Test Methods
Tensile Strength | Test Method |
---|---|
485 psi | ASTM D412 DIE C |
Tear Strength Test Methods
Tear Strength | Test Method |
---|---|
73 (ppi) | ASTM D624 DIE B |
Elongation Test Methods
Elongation | Test Method |
---|---|
4 % | ASTM D412 DIE C |
Shore A Hardness Test Methods
Shore A Hardness | Shore Hardness Test Method |
---|---|
51 | Hardness/Durometer Test Method |
Specific Gravity Test Methods
Specific Gravity | Test Method |
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1.540 | ASTM D792 |