SAIL FABRICS EXPLAINED
Nylon, Dacron, Kevlar, Mylar, Carbon……….what???
Nylon – Spinnaker Material
Nylon is used in spinnakers because of its light weight, high tensile strength, superior abrasion resistance and flexibility. However, it has a low modulus allowing too much stretch to be suitable for upwind sails. Nylon is more susceptible to UV and chemical degradation than polyesters and its physical properties can change due to moisture absorption.
Polyester (PET) – Dacron & Mylar
Polyethylene terephthalate, the most common type of polyester, is the most common fiber used in sailcloth; it is also commonly referred to by the brand name Dacron. PET has excellent resiliency, high abrasion resistance, high UV resistance, high flex strength and low cost. Low absorbency allows the fiber to dry quickly. PET has been replaced by stronger fibers for most serious racing applications, but remains the most popular sail cloth due to lower price and high durability. Dacron is the brand name of Dupont’s Type 52 high modulus fiber made specifically for sailcloth. Allied Signal has produced a fiber called 1W70 polyester that has a 27% higher tenacity than Dacron. Other trade names include Terylene, Tetoron,
Trevira and Diolen.
PEN fiber (Pentex)
PEN (Polyethylene naphthalate), commonly known by Honeywell's trade name "Pentex", is another kind of polyester fiber, which stretches only 40% as much as standard PET fibers, but about twice as much as Kevlar 29. Because it only shrinks about a third as much as a good
PET, PEN can not be woven as tightly; thus, woven PEN must be impregnated with resin making sails prone to damage from improper use and handling. PEN is better suited for making laminated sailcloth, where the fibers are laid straight for strength and are bonded to sheets of film for stability (e.g., PET film often called by one of its trade names Mylar),