Urethane RTV Rubber
RU-491 (95A Shore)
RU-491 A/B Two-Component, High Performance, 100% solids Urethane Elastomer (95A) developed for toughness and ease of processing. This system offers a Fast Cure Time of 8-10 Hours. Applications include automotive and concrete tooling, rapid prototyping, Special FX, and any application where high resiliency, durability, and a firm rubber are required.
Features:
* Extreme Durability
* Easy to Process
* Fast Cure Time- 8 to 10 Hours
Typical Physical Properties:
Viscosity (cps): 1600
Mix Ratio, by weight: 100A/20B
Color Mixed: Translucent AMBER
(For Cured Material)
Shore A Hardness: 95A (45D)
Tensile Strength (psi): 1425
Elongation %: 325
Tear Resistance (psi): 375
Specific Gravity: 1.08
Reactivity Data:
Gel Time: 10 minute
De-Mold Time: 1.5- 2 hours
Full Cure: 8-10 hours
**The addition of CS-83 Catalyst is used to create a quicker de-mold time where needed. Add 1% for 1-2 hour demold time.
Preperation of Master:
Urethane elastomers will adhere to most surfaces. A proper mold release must be used on all surfaces-- MR-150 or ER-2300 is recommended. Wood, plaster, stone, pottery, masonry, or any porous surface must be sealed with lacquer or clear shellac prior to applying release. PartAll Film #10 or shellac is suitable for sulfur & water based clays. Allow 24 hours to dry before preparing master with mold release. Plaster masters can release air when pouring larger molds due to some heat generated. Venting the base of your master by (drilling several ¼” holes) will release the air downward to avoid air release into mold cavity. Urethane RTV cures to a flexible rubber in above cure times. These products are safe to use as directed, check MSDS for safety information.
Mixing and Curing:
Before adding A to B, part B should be stirred or shaken for 1 minute to assure that any separated material is remixed. Select a clean, dry container for mixing. Avoid using wood or paper products, which could cause cure problems. Weigh the proper ratio A to B and mix well. Two containers may be used to assure that all materials are thoroughly mixed.
Pour mixture over master slowly allowing material to fill void and push air out of cavity. A vacuum chamber can be used to remove excess air bubbles before pouring. After mixture is poured a light mist of ER-2300 can be sprayed on top surface to break tension bubbles. Urethane RTV will cure to solid rubber at above cure time.
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.