Room Temperature Castable Polyurethanes
Sealthane's Room Temperature Castable Polyurethane systems provide the end user with the ability to rapidly manufacture parts exhibiting excellent toughness, abrasion resistance, and chemical
resistance. The room temperature system features two low viscosity liquid components that are mixed together prior to casting. Mixes may be either hand mixed or dispensed by machine and then poured into an
open mold to cast the finished part. In addition to open casting, Sealathane's room temperature systems can be reaction injection molded or spin cast to create a final part.
Sealathane may also be used to bond plastic and metal parts, providing for an exceptionally tough bond joint between materials
Sealathane is filler friendly and our technical team can supply the liquid resin with a pre-mixed amount of filler to improve properties, change the weight of the
finished part, and decrease the cost of the material. Sealathane has been manufactured with a number of fillers such as calcium carbonate,
talc, low density glass spheres, and silica. All materials used are optimized to improve performance while not affecting the processing characteristics of the system.
Sealathane is available in various colors such as white, black, gray, green, red, and blue and colors can be custom matched
to a user's specifications.
Sealathane is supplied in 1 gallon and 5 gallon kits, containing both the resin and curative..
Typical Properties
| Property | ASTM Test Method | RT50 | RT90 | RT93 | RTD70 | RTD75 |
|---|---|---|---|---|---|---|
| Hardness | 2240 | 50A | 90A | 93A | 70D | 75D |
| Ultimate Strength, psi | D412 | 900 | 3,900 | 3,500 | 5,000 | 3,000 |
| Ultimate Elongation, % | D412 | 820 | 725 | 450 | 120 | 10 |
| Tear Strength, Die C, pli | D624 | 105 | 480 | 460 | 300 | 110 |
Hand Mixing Processing Guidelines
Step 1: Weigh the Resin
Using a scale pre-weigh the amount of resin in a mixing container. Please note that the Sealathane polyurethane is supplied as a liquid and will remain liquid
under normal storing conditions. However it is possible that Sealathane will crystallize if eposed to temperatures below 65oF. If this occurs heat the
polymer to 140oF to thaw the resin. Allow the resin to cool to room temperature before use.
Step 2: Mix the curative
Add the desired amount of curative to the mixing conainer and mix with a spatula. Mix thoroughly, scraping the sides of the container,
to ensure a uniform and homogenous mix.
Step 3: Degas the Mix(Optional)
Time permitting, place the mixed system inside a vacuum oven for deairing. Pot life information supplied by UDC is based on small 50g batches and will change based on the size of the mixture.
The end user should run their own tests to determine if their application will allow for the use of vacuum.
It is recommended that the container placed in the vacuum be two to three times larger than the volume of the mix.
Pull vaccum until air is removed from the system.
Step 4 Apply Polyurethane Mold Release
Apply a proper amount of mold release onto the molding surface. Sealathane will stick to most metals and requires mold release to remove a
finished part. Failure to use mold release will cause sticking to the mold.
Stoner E236 Urethane Mold Release has shown good results. The end-user should test any mold release on a small scrap piece before molding.
Step 5 Pour into Mold
The mixture can be poured or injected into a mold for curing.
Step 6 Cure and Demold the Part
Sealathane will rapidly cure at room temperature and will develop enough green strenth to quickly remove from the mold. Please refer to the
supplied data sheets for recommended demolding times.
Step 7 Post Cure
In order to obtain optimum properties Sealathane should either be post cured at 200oF for 4 hours or allowed to sit at room temperature for 3 days
before actual field usage.