Polypropylene (Impact, heat and flex)
Polypropylene has a tensile strength of 4,500-6,000 psi, an elongation of 1-600% and an izod impact of 2.2-no break at all. For the best simulator of these properties, Hapco would recommend using Hapflex 666 or Hapflex 671. Both products come in slow and fast gel times and are available in a flame retardant version.
ABS (Impact resistance)
ABS has a tensile strength of 5,500-7,500 psi, an elongation of 5-25% with a flexural strength of 11,000 – 13,000 psi. Hapco’s Tuffalloy Series is a great candidate for simulation of ABS. You might also consider Ultralloy 109 or Hapflex 671, both of which have exceptional mechanical properties.
High-Temperature “Rubber” (heat resistance)
Hapflex 666 has a heat deflection temperature of 110°C and a service temperature of 135°C and Hapflex 671 has an HDT of 130°C and service temperature as high as 150°C (300°F). These would be our best recommendations for a semi-flexible product with high heat resistance.
Nylon 6-6 (Bearing and roller-type parts/gears)
Nylon comes in a variety of types, with each different type having a variety of grades. On average, it has a tensile strength of 7,500-11,000 psi, and an elongation of 30-100% with an izod impact of .6-2.2. Ultralloy 200 Series or Hapflex 671 would compare favorably to Nylon. By adding 20-25% milled glass to the products, you can make them very strong.
Polycarbonate (High impact with some flexibility)
Polycarbonate has a tensile strength of 9,000-10,500 psi with an elongation of 110-120% and a flexural strength of 12,500-13,500 psi. For simulating this product we would recommend using Hapco’s Ultralloy 200 Series, Ultralloy 900 Series or the Tuffalloy Series. Ultralloy 912 has exception impact strength, high HDT and is rate UL 94V0 @ .125” thick.
Polystyrene (Like polycarbonate but cheaper in production)
Polystyrene has a tensile strength of 5,200-7,500 psi, an elongation of 1.2-2.5% and flexural strength of 10,000 to 14,000 psi. For simulating this material we would recommend using Hapco’s Ultralloy 108 or 109.
Santoprene (rubber parts)
Santoprene is a thermoplastic rubber that comes in hardnesses ranging from 35 Shore A to 50 Shore D. IT exhibits good resistance to fatigue and has high tear strength. It also has good chemical resistance to many acids and aqueous solutions and performs well in thermo-cycling applications. For simulating these characteristics we would recommend the entire Hapflex Series which ranges from a 25 Shore A to 70 D in hardness.
Rigid True White
(For general purpose use, i.e., bezels and housings) – Hapco’s 108 and 109 are great general purpose materials. They are available in both “chemicl white” and pure white versions. Their low viscosity, convenient mix ratio (1:) and ease of use makes them very reliable for general casting applications.