Poly 15-3 Liquid Plastic


Poly 15-3 Liquid Plastic is a two-part, liquid polyurethane resin that cures (RTV) to a tan, Shore D80 plastic that has the feel of dense stone. This is a mineral-filled system with a simple 1A:1B mix ratio by weight. The filler makes Poly 15-3 a very economical, low-cost resin and also reduces exotherm so shrinkage is minimal; Poly 15-3 and Poly 15-3X (the faster-setting version of Poly 15-3) exhibit the least shrinkage on cure compared to other Polytek® polyurethane plastics. Poly 15-3 is a pourable plastic, but it can be easily thickened with PolyFiber II Thickener for brush-on application.

WARNING: This product can expose you to chemicals including Diisononyl phthalate, Cumene, Napthalene, Ethyl benzene, Benzene and Toluene, which are known to the State of California to cause cancer and/or reproductive harm. For more information, go to www.P65Warnings.ca.gov


Current Stock:
Looking for larger sizes (e.g., drum kits)?
Please contact Customer Service at 800-858-5990 or sales@polytek.com

Technical Specifications

Mix Ratio by Weight:
Shore Hardness:
Pot Life:
15 min.
Demold Time:
12-16 hr.
Cured Color:
Mixed Viscosity:
2,000 cP
Specific Volume:
18 in³/lb
Specific Gravity:
Linear Shrinkage:
0.0006 in/in
2.6 %
Tensile Strength:
3,509 psi
Elastic Modulus:
202,276 psi
Flexural Modulus:
479,648 psi
Flexural Strength, 5% Strain:
5,232 psi
Max Exotherm:
Shake or Stir Part A & Part B before use. Demold time varies with thickness of casting. The thinner the casting, the longer the demold time. Shrinkage in polyurethane resins is caused by gelling while hot then cooling.
The color of polyurethane Part Bs may change in color from batch to batch or may darken with age, but product performance is not affected.

More Information

Material Calculator

Technical Bulletin

Safety Data Sheet - Part A

Safety Data Sheet - Part B

Kit Components
Poly 15-3 Components
5-lb kit includes: 2.5 lb of Poly 15-3 Part A (~1 quart)
2.5 lb of Poly 15-3 Part B (~1 quart)
20-lb kit includes: 10 lb of Poly 15-3 Part A (~1 gallon)
10 lb of Poly 15-3 Part B (~1 gallon)
100-lb kit includes: 50 lb of Poly 15-3 Part A (~5 gallons)
50 lb of Poly 15-3 Part B (~5 gallons)

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