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Silpak RU-491

Silpak RU-491 are two-component, high performance, 100% solids Urethane Elastomers developed for their toughness and ease of processing. Applications include automotive and concrete tooling, rapid prototyping, Special FX, and any application where high resiliency, durability, and a firm rubber are required.

Polymer Name: Polyurethane Thermoset Elastomer (unspecified)

End Uses: Prototyping, Tooling

Features: Durable, Easy Formulation, Easy To Modify, High Resilience

Technical Data Sheet
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Knowde Enhanced TDS

Identification & Functionality

Chemical Family
Technologies

Features & Benefits

Unique Characteristics
  • Extreme Durability
  • Easy to Process
  • Long Work Time

Applications & Uses

Plastics & Elastomers End Uses

Properties

Physical Form
Typical Properties
ValueUnitsTest Method / Conditions
Color MixedTranslucent Amber
De-mold Time (Reactivity)1.5- 2 hrs
Full Cure (Reactivity)44418hrs
Elongation 325%
Coverage26in3/lb
Gel Time (Reactivity)10min
Mix Ratio, by weight100 A/ 20 B
Mixed Viscosity1600cps
Hardness45Shore D
Hardness95Shore A
Hardness95Shore A
Specific Gravity1.08
Tear Resistance 375ppiASTM D-624
Tensile Strength 1425psiASTM D-638

Safety & Health

Handling and Safety

Use proper equipment—gloves, glasses and apron when using materials. Avoid direct contact with skin and eyes. If skin contact occurs, clean area with waterless hand cleaner or isopropyl alcohol. For eye contact, flush eye with water for 15 minutes and call physician. Use materials under adequate ventilation.

Packaging & Availability

Pacakaging
  • Quart Kit
  • Gal Kit
  • 5 Gal Kit

Storage & Handling

Storage/ Shelf Life

A and B components must be stored in their original, unopened containers at temperatures between 65F and 85F. Shelf life of materials when kept in unopened sealed containers, at the recommended storage conditions, is 6 months. Containers should not be opened until ready for use. Once containers are opened, material should be used in a short time period. Pre-test any aged material before using. Molds or parts should be cleaned with a soap solution and completely dried prior to storing them in a dry, cool environment. Avoid stacking or exposing them to environmental elements—UV and moisture.