DuroFlex 85 is a tough, durable, polyurethane elastomer of 85 Shore A, used for mould making or prototype parts requiring high tear strength and excellent abrasion resistance, fast-curing rubber, which has been developed specifically for prototyping and model making applications. And is very low in viscosity making it easy to mix and pour without trapping bubbles.

It is excellent for casting decorative objects, production parts, tools, models, patterns, duplicate masters and more. With the addition of Poly Colour Dyes, PT Flex products can be used to cast parts of any colour.

Mould Preparation
Ensure that the mould is clean and dry and if the mould is made from metal, wood or resin, use a wax based release agent such as a Macwax. Wooden moulds should be sealed well before casting.

Mixing Instructions
Shake the Part A container thoroughly in order to homogenise the resin. Ensure that both components are at least 20°C before mixing. Part A should be mixed with Part B according to the indicated mixing ratio. Both components should be thoroughly mixed, care should be taken to avoid air entrapment and make certain that material at bottom and sides of container is thoroughly stirred into the centre. After thorough mixing, the material should be poured into the mould. To avoid air entrapment, pour the material slowly, and into one place in the mould. In order to obtain a bubble free cast, the material should be degassed after mixing and pouring. Mixing, pouring and degassing must be completed within the stated pot life.

Curing and post curing
The precise demould time will vary with the casting thickness, as thin sections will cure slower than thicker sections. If cured at room temperature, the casting can generally be demoulded after 1 hour. If quicker demould times are required, the product can be cured at elevated temperatures (up to 80°C). Curing at high.

The details above are approximate due to the end user working environments and working temperatures.
Parts that cure with minimal temperature rise exhibit minimal shrinkage.

Mix Ratio by Weight - 100 A : 100 B
Mixed Viscosity (cP) - 600 - 900
Pot Life (200g,  25°C) - 4.30 - 5.30  Minutes
Cured Colour - Amber
Demould Time (25°C) - 1 Hour
Full Cure Time (25°C) - 7 Days
Shore A Hardness - 83 - 87
Density - 1.02 - 1.07