Properties of polyurethane elastomers

Polyurethane elastomers are typical multi-block copolymers, where the molecular chain consists of flexible chain segments with a glass transition temperature below room temperature and rigid chain segments with a glass transition temperature above room temperature. The oligomer polyol constitutes the flexible chain segment, diisocyanate and small molecule chain extender constitutes the rigid chain segment. Flexible and rigid chain segment and rigid chain segment of the block structure determines the specificity of its performance, mainly in:

(1) wide range of hardness. Ordinary rubber hardness range is generally in Sauer a20-90, the hardness range of plastics is about Sauer a95-Sauer d100, polyurethane elastomers can reach as low as Sauer a10 or less, and as high as Sauer d85, and do not need filler assistance.

(2) Higher strength and elasticity. Polyurethane elastomers can still maintain high strength and elasticity in a wide range of hardness.

(3) Excellent abrasion resistance, 2-10 times that of natural rubber, known as “abrasion resistant rubber”.

(4)Excellent resistance to water, grease and chemicals.

(5) High impact resistance, high fatigue resistance and high vibration resistance, suitable for high-frequency flexing applications.

(6) Good low temperature resistance. Low temperature brittleness is about -30℃ or -70℃ or less.

(7) Excellent thermal insulation properties. Due to the low thermal conductivity, compared with rubber and plastic, the thermal insulation effect is better.

(8) Good biocompatibility and anticoagulant properties.