Dyneema

A trade name for ultra-high-molecular-weight polyethylene fibre used in high-strength, low-stretch marine ropes and fabrics.

The fibre has a high strength-to-weight ratio, floats, absorbs little water and resists many chemicals and ultraviolet exposure. Marine uses include halyards, control lines, lashings, soft shackles, standing rigging and protective textiles.

Performance depends on the product grade, construction, cover, splices, bend radius and temperature. UHMWPE can creep under sustained load, lose strength through poor terminations or tight bends, and be vulnerable to heat and abrasion despite its high fibre strength.