VFI®-145 95 A Polyurethane Casting Rubber

VFI®-145 95 A Polyurethane Casting Rubber

VFI-145 95 A Polyurethane Casting Rubber is a fast setting, 1:1, hard rubber with good durability and rebound properties. It is capable of being a hand pour material when making smaller parts or for use in an injection system. The material’s fast setting capabilities allow for a quick demold time that increases part production. It provides excellent physical properties, such as good chemical resistance and low-temperature flexibility for increased use through multiple cycles. VFI-145 has a workable viscosity, which allows for increased part sizes that maintain final physical properties. This tough rubber has been used in a variety of applications like mold and model making, prototyping, and industrial part making. 

VFI-145 95 A Polyurethane Casting Rubber from VFI is an injectable or pourable hard rubber for quickly making molds, models, industrial parts, and more.

Features & Benefits

  • Fast demold time for a quick turnaround on parts with good green strength
  • High amine content provides good chemical resistance and low-temperature flexibility
  • Ultra-easy 1A:1B mix ratio by volume allows for easy mixing and pouring
  • Workable material that allows parts to be poured or injected
  • Great material for mold, model, and industrial part making
  • Low viscosity helps limit the amount of trapped air and fills all necessary cavities

Instructions for Use:  

Mold Preparation 

Ensure all molding equipment and surfaces are clean and free of oils, dirt, or debris. The mold should be properly sealed and released to prevent unwanted adhesion when demolding. Using a release agent is required to help extend the life of the mold. Heating the mold between 70°F-150°F before use can accelerate the curing process, decreasing the demold time. Heating will also decrease the pot life. Compatible molds include urethane, metal, and platinum silicone when properly prepared.  

Casting Process  

The B side (Poly) must be slowly premixed to minimize air entrapment. Small volumes can be hand-mixed, but larger quantities should be mixed with a power mixer or injection equipment. Once measured into containers, pour the B side material into the A side (Iso) material, and mix until uniform. Scrape the bottom and sides of the container while mixing. Transfer to a new container to mix again until uniform. The material must be fully mixed and used before the duration of the pot life. The pot life will shorten if the temperature exceeds 72°F. Mix times may vary depending on volume and mixing method.  

If you are pouring or injecting over 5 pounds of material, a different material that has a longer working time should be used. When casting, pour the material in a single spot at the lowest point of the mold.  

Leave the material to cure for at least 15 minutes at room temperature before demolding. Full physical properties occur after 3 days at room temperature, but they can be achieved faster if the material is post-cured at 150°F for a minimum of 2 hours. Post-curing is recommended at thinner pours. 


*Always read the safety data sheet before working with chemicals   

Use chemicals only as directed and for their intended purpose. Do not dispose of chemicals down the drain. Most chemicals must be disposed of as hazardous waste. 

PPE to avoid unnecessary exposure:  

  • Eye protection – wear approved safety glasses and any additional eye protection as necessary 
  • Hand protection – wear chemically resistant protective gloves (nitrile, butyl, or neoprene) 
  • Skin and body protection – wear suitable protective clothing 
  • Respiratory protection – in case of insufficient ventilation, wear suitable respiratory equipment. Respirator selection must be based on known or anticipated exposure levels, the hazards of the product, and the safe working limits of the selected respirator 

Product Limitations  

The product contains isocyanate, which can irritate the skin and is toxic if inhaled. It is not UV color stable and has no long-term UV testing.  

  • Incompatible materials – A side: strong bases, acids, alcohols, amines, and water. B side: strong oxidizers 
  • Conditions to avoid – heat and incompatible materials 
  • Chemical stability – stable under normal storage conditions 
  • Reactivity & hazardous reactions – no dangerous reaction known under normal use  
  • Hazardous decomposition products – may include, and are not limited to, oxides of carbon as well as oxides of nitrogen and isocyanates for the A side  

Potential Health Hazards  

  • May cause stomach distress, nausea, or vomiting if swallowed.  
  • May cause respiratory tract irritation. A side may cause allergy and asthma symptoms or breathing difficulties if inhaled.  
  • Causes skin irritation or sensitization: redness, edema, drying, defatting, and cracking of the skin. 
  • Causes serious eye irritation: discomfort, pain, excess blinking and tear production, marked redness, and swelling of the conjunctiva.  

*If you are experiencing any of these symptoms, seek medical advice or attention. Call a poison control center or doctor if swallowed.   

Application Methods:

  • Inject Inject
  • Pour Pour

Available Packaging:

  • Tote
  • Drum
  • 5 Gallon
  • 1 Gallon